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The Genesis of Language
Studies in Anthropological Linguistics
3
Editors Florian Coulmas Jacob L. Mey
Mouton de Gruyter Berlin · New York · Amsterdam
The Genesis of Language A Different Judgement of Evidence
edited by
Marge E. Landsberg
Mouton de Gruyter Berlin · New York · Amsterdam
1988
Mouton de Gruyter (formerly Mouton, The Hague) is a Division of Walter de Gruyter & Co., Berlin
Library of Congress Cataloging-in-Publication Data The Genesis of Language. (Studies in anthropological linguistics ; 3) Selected papers from the Symposium on the Origins of Language held during Phase II of the Xlth International Congress of Anthropological and Ethnological Sciences, August 2 0 - 2 3 , 1983, Vancouver, B.C., Can. Includes index 1. Language and languages—Origin —Congresses. 2. Anthropological linguistics — Congresses. 3. Biolinguistics—Congresses. I. Landsberg, Marge E., 1925 — II. Symposium on the Origins of Language (1983 : Vancouver, B.C.) III. Series. P116.G46 1988 401 88-1226 ISBN 0-89925-370-9 (alk. paper)
Deutsche Bibliothek Cataloging-in-Publication Data The genesis of language : a different judgement of the evidence / ed. by Marge E. Landsberg. — Berlin; New York; Amsterdam : Mouton de Gruyter, 1988 (Studies in anthropological linguistics ; 3) ISBN 3-11-011087-3 NE: Landsberg, Marge Ε. [Hrsg.]; GT
Printed on acid free paper. © Copyright 1988 by Walter de Gruyter & Co., Berlin. All rights reserved, including those of translation into foreign languages. No Part of this book may be reproduced in any form — by photoprint, microfilm, or any other means — nor transmitted nor translated into a machine language without written permission from Mouton de Gruyter, a Division of Walter de Gruyter & Co., Berlin. Typesetting: Arthur Collignon GmbH, Berlin. — Printing Ratzlow-Druck, Berlin. — Binding: Dieter Mikolai, Berlin. — Printed in Germany.
Acknowledgements
As Symposium Organizer and Editor, my debts of gratitude are many: to the Xlth International Congress of Anthropological and Ethnological Sciences, where these papers were presented, for their exemplary organization and gracious hospitality; to Henrietta Cedergren, Linguistics Director, and Bjorn Simonsen, Executive Secretary, for their outstanding administrative endeavors on our behalf; to my fellow participants, for having so generously contributed to the Symposium's success by their friendship and scholarly cooperation; to Ofer Bar-Yosef (Hebrew University) for critically reading the Preface; to Florian Coulmas, Scientific Editor (Mouton), for his unflagging patience and professional guidance regarding this publication; and above all to my husband, Morris Landsberg, for his staunch support, appreciated more than words can say. Grateful acknowledgement is made to Horst D. Steklis (Rutgers University) and to the Academic Press, Inc. (London), Ltd., for their permission to reprint the article entitled: "Primate communication, comparative neurology, and the origin of language re-examined." appearing in the Journal of Human Evolution, (1985) Volume 14. 157—173. Reprinted by permission of the author and the Academic Press, Inc. (London), Ltd. A version of Harry J. Jerison's paper was published in J. Mikovsky and V. J. A. Novak (eds.), Evolution and Morphogenesis. Proceedings of the International Conference on Evolution and Morphogenesis, Prague, 1985. 701—708. Praha: Academica. It should also be mentioned here that the above two papers, as indeed the other fourteen included in this volume, were presented at the Symposium on Origins of Language, Phase II of the Xlth International Congress of Anthropological and Ethnological Sciences, August 20 — 23, 1983, Vancouver, B. C., Canada. Marge E. Landsberg Symposium Organizer and Editor
Preface
It is crucial to our perception of our present human condition, to acquire a fuller knowledge and understanding of our vocal beginnings. However, the very difficulty of this question has led to its scientific neglect, with the result that we have had so far little firm evidence to guide our judgements or constrain our speculations. Anthropologists, biologists, archaeologists, linguists, prehistorians and inhabitants of adjacent intellectual realms have now begun to inquire how, if at all, it may be possible to gather objective and verifiable data about the genesis of human language. This renewed interest has been well represented in the three former important symposia on language origins. However, since it is the nature of science to be forever in flux, the need and importance of an updated work is ever obvious. The present work is a collection of current research data representing the latest available investigation and interpretation of evidence. It came into existence as the result of a Symposium on the Origins of Language, held during Phase-II of the Xlth International Congress of Anthropological and Ethnological Sciences, August 20 — 23, 1983, Vancouver, B.C., Canada. Thirtythree scholars from a wide spectrum of interdisclipinary backgrounds and of world-renown in their fields, were invited to prepare an up-to-date research report on their findings. From these the present thirteen papers were selected as most informative and representative. As can also be seen from the title, evidence is a keyword here. For although the Societe de Linguistique de Paris in 1866 felt obliged to suspend all further discussion of the question of glottogenesis because of its often speculative nature, the situation has changed considerably, with accelerated research yielding the publication of "hard facts," especially during the latter half of the twentieth century. Clearly, now the more fruitful position is that the question of glottogenesis deserves, indeed demands, intensive modern in-depth investigation. This work stands as a testimony to the ability of contemporary science to offer proof capable of establishing facts, as well as the means of proving or disproving such alleged facts. For although assumption and hypothesis may
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be the backbone of science, nothing can outshine the presentation and interpretation of existing data. The present investigation which considers four levels: (1) neurobiological advances, (2) perceptual bases, (3) fossil evidence, and (4) linguistic evidence, represents current approaches to language origins theories. The first section discusses evolutionary neurobiology and the origin of language; the second section considers the antecedents and perceptual bases for the evolution of speech; the third section examines the evidence from artifacts and fossils, considering implications of the evolution of the vocal apparatus and tying up with the anteceding discussion concerning the development of speech-related specializations; the fourth section deals with evolutionary aspects of language behavior. Most satisfactory and rewarding in a transdisciplinary discussion of this kind is to reach the point where all the data, all the separate bits and pieces of informations fall together and arrange themselves into a marvelously complex and yet simple kaleidoscopic picture, enabling us to draw up a fairly consistent and unified model for the theories we have for the origin and evolution of language and speech. Thus, when considering the data submitted by researchers dealing with primate communication, comparative neurology, evolutionary neurobiology, perception and cognition, the state of the larynx at a certain point in time, we can see where information converges. However, interestingly enough, it will be noted that in any present discussion of the origins of language the most disappointing aspect is the lack of linguistic contributions. This may be due, for one, to the immense time-depth concerned, prohibiting successful and valid retro-reconstructions, at best but approximations and abstractions rather than realities, and this missing information is precisely the one we crave. It is true that the Nostratic linguists are doing a spectacular job, but even the most audacious amongst them would not postulate a linguistic retro-horizon beyond 10.000 years. This raises the question of how educated a guess we can venture beyond such a date; that is, what may human language have looked like, say, 20.000 or 30.000 years ago. We are well acquainted with Lieberman and Crelin's work, and the critical literature that developed around their publications, which may seem now already a bit outdated. The present volume contains Krantz' interesting qualitative and temporal approximation. What is yet lacking is a spatial
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approximation which might, perhaps, afford us some indication as to what man's first utterings may have looked or rather sounded like. In order to consider a possible linguistic cradle for mankind, however, we would of course first have to solve the riddle of man's biological cradle. The current scientific consensus still places the cradle of man in Africa (2.5 — 3.0 Myr), no site but Ubeidiya, three kilometers south of the Sea of Galilee (1.0—1.5 Myr), in Asia or Europe being older than 1.0—1.2 Myr. Ubeidiya might, therefore, be the oldest site outside Africa (Bar-Yosef, pers. comm., 2.7.'85). Further excavations in non-African sites, such as the one intended by Bar-Yosef and Tchernov for this summer five kilometers south of Ubeidiya in the Jordan Valley, may bring more evidence to bear. Till then it remains fascinating to ponder the question of whether it was in the Land of the Bible, after all, that man achieved his language and his humanity.
List of Contributors
Numbers in parentheses indicate the pages on which the authors' contributions begin.
Bernard H. Bichakjian (113, 145), Faculteit der Letteren, Sectie Franse Taal- en Letterkunde, Katholieke Universiteit, Erasmuslaan 40, 6525 GG Nijmegen, The Netherlands. Joseph L. Fischer (67), Department of Anthropology, Tulane University, New Orleans, LA 70118, U.S.A. Ivan Fonagy (183), Centre National de la Recherche Scientifique, 1 squ. Claude Debussy, 92160 Antony, France. Kathleen R. Gibson (149), Dental Branch, University of Texas, P.O.B 20068, Houston, TX 77225, U.S.A. Harry J. Jerison (3), Department of Psychiatry and Biobehavioral Sciences, UCLA Medical School, Los Angeles, CA 90024, U.S.A. Gr over S. Krantz (173), Department of Anthropology, Washington State University, Pullman, WA 99164, U.S.A. Marge E. Landsberg (205), 1 Shikmona Street, Bat-Galim, Haifa 35014, Israel. Saul Levin (219), Department of Classical and Near Eastern Studies, State University of New York at Binghamton, Binghamton, Ν. Y. 13901, U.S.A. Andrew Lock (89), Department of Psychology, Fylde College, University of Lancaster, Bailrigg, Lancaster LAI 4YF, England. Dennis L. Molfese and Victoria J. Molfese (11), Department of Psychology, Southern Illinois University at Carbondale, Carbondale, ILL. 62901, U.S.A. Walburga von Raffler-Engel (227), 372 Elmington Avenue, Nashville, TN 37205. Horst D. Steklis (37), Department of Anthropology, Douglass College, Rutgers University, New Brunswick, N.J. 08903, U.S.A. Richard M. Warren (101), Department of Psychology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201, U.S.A. Jan Wind (137), Institute of Human Genetics, Free University, P.O. Box 7161, 1007 MC Amsterdam, The Netherlands. Willem de Winter (247), Department of Psychonomics, Amsterdam University, P.O.B. 20218, 100 HE Amsterdam, The Netherlands.
Contents
Part I Neurobiological advances Evolutionary neurobiology and the origin of language as a cognitive adaptation Harry J. Jerison
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Language development and biological programming: behavioral and electrophysiological indices Dennis L. Molfese and Victoria J. Molfese
11
Primate communication, comparative neurology, and the origin of language reexamined Horst D. Steklis
37
Part II Perceptual bases Grasping and the gesture theory of language origins Joseph L. Fischer
67
Ways to accelerate progress in glottogonic research Gordon W. Hewes
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Implication and the evolution of language Andrew Lock
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Perceptual bases for the evolution of speech Richard M. Warren
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Part III Fossil evidence Neoteny and language evolution Bernard H. Bichakjian
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Language evolution and paedomorphosis Jan Wind
137
Language evolution and paedomorphosis. A reply to Jan Wind 145 Bernard H. Bichakjian Brain size and the evolution of language Kathleen R. Gibson
149
Laryngeal descent in 40.000 year old fossils Gr over S. Krantz
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Part IV Linguistic evidence Live speech and preverbal communication Ivan Fonagy
183
On linguistic territoriality, iconicity and language evolution . 205 Marge E. Landsberg Vestiges of primeval phonology in certain ancient languages Saul Levin
219
The synchronous development and kinesis: Further evidence 227 Walburga von Raffler-Engel Behavioral flexibility and the evolution of language Willem de Winter
247
Index
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Part I Neurobiological advances
Evolutionary neurology and the origin of language as a cognitive adaptation Harry J. Jerison
Abstract Neurologically, human language is peculiar as an adaptation for animal communication because of the enormous amounts of nervous tissue that it encumbers. Communication in animal species is normally handled by behavioral and morphological adaptations that present unequivocal messages about the state of the 'sender' and to which the 'receiver' responds in stereotyped ways. Information-transfer is achieved economically, involving relatively little neural tissue. It is reasonable to assume that this has been true in the evolution of most primates as well as other mammals. It has not been true in human evolution. If human language evolved as a cognitive adaptation, i. e., comparable to vision or hearing as a method for knowing reality, then the enormous neural investment in this brain system is understandable, because such an investment is typical only for cognitive systems. This view also explains why the adaptation for communication in the human species is so maladaptive, that is, why a behavioral system that permits so many failures of communication evolved.
Introduction I will be concerned with functional aspects of language about which evolutionary statements can be made, and with aspects of evolutionary biology and neurobiology that are relevant for human language. I propose three conjectures, or hypotheses, and this note is about these conjectures. First, in its early evolution, language was primarily an adapation that contributed to perceptual and cognitive functions in the human species for mapping the external world, and thus constructing the experienced external world.
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Second, despite its central importance for communication in living human groups, in its early evolution, language was only secondarily a response to selection pressures for improved communication. Finally, the evolution of language interjected a special element into the reality constructed by hominid brains. Since humans do, in fact, communicate with language as well as use it in the construction of their reality, human linguistic communication has an element of a sharing of realities by those in communication — sharing consciousness, as it were. This has interesting implications for the evolution of consciousness of self.
Mapping the external world The hypothesis about mapping is based partly on a scenario about what actually happened in hominid evolution and about the way the brain works in developing cognitive maps, and partly on a recognition that only 'mapping' encumbers large amounts of brain tissue. The evolutionary narrative has early hominids invading an environmental niche that was inappropriate for primates in crucial ways. The niche was of a social predator. In living species such as wolves that are adapted to such niches, there are sensory and brain/ behavior adaptations that enable individuals to navigate, control, and defend an extensive territory and range. This is typically (I suggest) an 'olfactory' and scent-marking system that is essentially paleocortical in its localization. Language, I suggest, began as an adaptation in a species of primate, with the diminished olfactory system typical of higher primates, of the auditory-vocal (sensorymotor) apparatus and nervous system to contribute to the same kind of cognitive map of the external world. Adaptations for mapping the external world are brain functions that are easy to think about neurologically. They are extensions of those functions that convert sensory signals into nerve impulses, patterns of nerve impulses, and eventually into what we conventionally call visual fields, auditory signals, body images, and so on. This neural activity eventually sums up to a map or set of maps that is a picture of the external world. The brain activity of constructing a cognitive map to represent reality is, of course, the construction of reality itself as we experience
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it, and this is an important insight about what brains do. Brains construct real worlds in which animals live. This is an old insight, which we can share with the classical philosophers, though we may have a much better picture of how the construction is done by the brain. We know much more about how the brain handles information. But the conclusion remains: A major aspect of the brain's work is to construct a real world, and we may extend this conclusion by recognizing that it is this activity, this construction of reality, that is probably the unusual activity that requires very large amounts of brain tissue in the larger-brained animal species.
More on language and cognitive maps The sensory and neural equipment available to the hominids for the niche that they were to invade early in their history was, we must assume, the normal armament of a primate species. Their problems with the niche were problems that any primate species would face in attempting to make a living as social predators. To appreciate these, we may consider how species well-adapted to such niches function today. The living species that are exemplars of the adaptation are the wolves, and one of their major behavioral adaptations is based on the use of specialized olfactory and scentmarking systems. Wolves navigate and apparently 'know' an extensive territory and range that covers tens of square kilometers. They do this by using many cues, but outstanding among these are cues from urine and other scents, with which the territory is marked. They sense these marks as deposited by other animals, wolves and potential prey, within the range. The information they handle must be enormous, both as information at the sense organs and the olfactory bulbs, and as information processed more centrally in the classic 'olfactory brain', the rhinencephalon. The system is rarely called olfactory nowadays, because too many other functions have been assigned to it, including emotional and motivational dimensions of behavior. But parts of it, especially the hippocampus of the 'old brain' or paleocortex, are still deeply implicated in the activity of constructing cognitive maps (O'Keefe, 1985; Olton, 1985). I have introduced language and cognitive maps by discussing scent-marking and the life-space of wolves. It is the life-space that
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is crucial: the fact that it takes a large number of prey individuals, spread over a broad range, to support a small number of predators. And the predators must 'know' their ranges and territories, must know the area in order to be able to harvest a sufficient number of prey. If early hominids lived this kind of life they would have had to live in an unusually extensive area for primates. They would have had to know — i. e., have 'mapped' — the area, in order to be able to navigate their territory surely and easily. If it is true that the maintenance of such cognitive maps over time (remembering them to keep them useful and up-to-date) requires active participation by paleocortical brain structures such as the hippocampus, then there would have been a major information-handling problem for primates in getting signals to those structures. The problem arises because of the serious reduction during the evolution of the higher primates of the major sensory input channel to that structure from the external environment, the olfactory bulbs. The problem cannot be as simple as that, of course. Brain structures do not act as simple building blocks in which one behavior-control system is contained in one structural location. It is more correct to conceptualize the problem functionally. The idea is that primates as a group are deficient in a major sensory system that is peculiarly adapted to handle spatial information from memory, as opposed to spatial information from immediate experience. We may think of the visual system as adapted for the latter function, i. e., spatial information from immediate experience, and I am suggesting here that in many mammals, the olfactory system is adapted for the former function, for the memory of spatial information. Lacking a significant part of the 'olfactory' system, yet requiring the functional capacity for mapping in memory as well as immediate experience, a species of primate in the niche of a social predator had to evolve a sensory system that could interact with the memorymapping system. It is important to interject a warning. We must reject the semantic trap of equating 'olfactory' in humans, which we know as primitive chemical sensory functions, with the function of the homologous system in nonprimates, and with the nonolfactory functions of the same anatomical system in mammals. The system obviously has extensive and significant cognitive functions related to mapping the external environment, and maintaining and retaining the maps in what we call the [short-term and other] memory systems.
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I suggest that the early hominids, in this setting, did evolve such an equivalent system that could interact with the paleocortical olfactory system: an auditory-vocal system. In its early evolution this system could have been little more than an addition to other aspects of the mapping of external reality that, as I have suggested earlier, is the fundamental function of much of the enlarged brain of many vertebrate species. If we imagine a pointilist picture of reality, with each element contributed to by information from the several sensory systems, we may imagine this picture as containing linguistic points as well as auditory and visual and tactile points, all contributing to the constructed reality.
Language and communication Animal communication is usually a neurologically cheap adaptation, supported by relatively small amounts of neural machinery, and handled by stereotyped behaviors and specialized sensoryperceptual systems. The auditory-vocal system performing cognitive functions of mapping the external world 'linguistically' would have peculiar attributes when it also functioned as a mammalian communication system. Let us be philosophical about the significance of the brain's work in constructing reality. The construction is clearly based on the work of the sensory and motor systems of the brain. In our personal lives the construction works as our knowledge of the external world, which we know as a truly real world, although we recognize some philosophical problems in determining what is really real. Consider now what would happen if among the sensory elements in the construction there is one that is also an element of communication. Communication with that element would effectively share the reality itself that the individual experiences. That is the peculiar feature of human language. When we communicate with it we share realities. This is so odd a thought that it takes a bit of accommodation to accept it. Yet there is plenty of evidence that it is true. The simplest is in the effectiveness of the written word as a source of imagery about real events, the ease with which we enter the lives of others when they are described with language, the reality of the world we enter and live in as we read a realistic novel.
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Our ordinary communications also have this character, and that is also one of the difficulties that we have in thinking about animal 'languages'. In our ordinary communications we routinely expect to share images, and we use this to avoid direct commands. We may say: "There is a car coming," to warn a friend to be attentive and avoid an accident. Our statement invites the friend to share our experience of the moment and to act on that experience. A normal animal communication in other species would be of the form: "Run away," or even "Climb the tree." It would be a straightforward command, and Cheney and Seyfarth's (1985) vervets giving warning calls about the presence of eagles or leopards or snakes are exemplars of this kind of communication.
Language, shared consciousness, and self-consciousness When we communicate with verbal language, according to this argument, we share consciousness with one another, because we share a constructed reality. Language, like vision and hearing, contributes to the construction. This argument implies a biological and evolutionary explanation for self-consciousness as a human trait, at least in terms of its biological function. Self-consciousness would have to arise to distinguish the reality generated by one's own information (sensory, linguistic, etc.) from the reality generated by verbal information from another individual. It would lead to problems, and sometimes does, when we cannot distinguish the really real world; that is, the world our brain normally builds, from worlds it can build using only the evidence of language, whether our own or someone else's. According to this view, language has a central role in the construction of self-consciousness. Other animal species, all of which lack the human kind of language, necessarily lack a human kind of self-consciousness. This is not to denigrate other species. Their status in the grand scheme of things need not depend on whether they share a particular kind of adaptation with us. It is, rather, to identify human self-consciousness as a species-typical human trait, which occurs as a result of a unique and peculiar human adaptation. And let us not be distracted by experiments that demonstrate a selfawareness in other species, which enables well-trained chimpanzees,
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for example, to recognize their images in a mirror as their images. Like chimpanzee 'language' learned from humans, this behavior demonstrates a respectable behavioral capacity, but it does not demonstrate that this capacity is based on the brain controls that control the behavior in humans, or that it plays the same role in the life history or natural history of individuals of other species that it does in the human species.
Epilogue This set of assertions about the evolution of language contains, essentially, hypotheses. Some are well-supported by available data, some are quite speculative; some are readily testable, and some, like the ones about self-consciousness, may be testable only when we have established elaborate enough methods of communication with other species to quiz individuals critically about their personal experiences (cf. Jerison, 1986). References Cheney, D. L., and R. M. Seyfarth 1985 Social and non-social knowledge in vervet monkeys. Philosophical Transactions of the Royal Society (London) B308. 187 — 202. Jerison, H. J. 1986 The perceptual worlds of dolphins. In R. J. Schusterman, J. E. Thomas, and F. G. Wood (eds.), Dolphin Cognition and Behavior: A Comparative Approach. 141 — 166. Hillsdale, New Jersey: Earlbaum. O'Keefe, J. 1985 Is consciousness the gateway to the hippocampal cognitive map? A speculative essay on the neural basis of mind. In D. A. Oakley (ed.), Brain & Mind. 59—98. London: Methuen. Olton, D. S. 1985 The temporal context of spatial memory. Philosophical Transactions of the Royal Society (London) B308. 7 9 - 8 6 .
Language development and biological programming: behavioral and electrophysiological indices Dennis L. Molfese and Victoria J. Molfese
Abstract The present study reviews evidence concerning early specialization of the cerebral hemispheres for language. Various methodologies including anatomical procedures, work with brain-damaged populations, and electrophysiological procedures all point to the early specialization during infancy of the cerebral hemispheres for language processes. However, while the evidence clearly supports the view that hemispheric specialization appears early in development, research involving two perceptual cues, Voice Onset Time and Place of Articulation, clearly indicates that such early asymmetries are multidimensional and develop in a variety of ways. Moreover, these early asymmetries are differentially able to predict long-term outcomes of later language development. Apparently it is the specific processes which are lateralized rather than the mere presence of hemisphere differences which are the best predictors of later development. In recent years, the role of biological components in language development has received increased recognition. Evidence obtained from young infants of asymmetrical anatomical structures, lateralized cerebral functioning and of speech discrimination abilities have all been used to support the notion of a basic biological component to language development. Clearly, this notion is not new. Lenneberg (1967) argued that a biological substrate exists which subserves language abilities. Evidence for such a view, he noted, could be seen at a number of levels in humans. For example, even at the gross morphological level of the vocal tract, humans (unlike other primates) are structured in a certain way to produce a wide variety of speech sounds (Lieberman, 1977). The pinna itself is structured to
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favor the perception of sound frequences which characterize the majority of important speech cues. At the neurological level, Lenneberg (1967) argued that language acquisition was linked to brain organization. For Lenneberg (1967), lateralization of brain functions was a biological sign of language ability (Lenneberg, 1967: 67). Although investigators have challenged some of Lenneberg's specific hypotheses on lateralization and language development, his general view that there are specific biological underpinnings for language which may facilitate language development continued to be supported (Segalowitz, 1983; Segalowitz and Gruber, 1977). The goal of the present study is to present recent evidence of the influences of innate biological components on language abilities and development.
A. Anatomical studies There is growing evidence from anatomical studies that cerebral asymmetries are present early and, indeed, may be innately determined. Early work by Geschwind and Levitsky (1968) reported that the left hemisphere temporal planum in adults is markedly larger than that in the right. Since this region corresponds approximately to the region called Wernicke's Area, which is thought to mediate language functions, such anatomical asymmetries were interpreted as support for the functional asymmetry findings reported in behavioral research. Later work by Wada (Wada, 1969; Wada, Clarke and Hamm, 1975) examined the anatomical asymmetries in the brains of infants. Results of studies on over 100 infant brains (most between twenty-nine gestational weeks and forty-eight gestational weeks) and 100 adult brains showed anatomical asymmetries in the infants which where similar to those found in the adults. In particular, the left temporal planum was found to be larger than the right in most of the infant and adult brains studied. These findings were later confirmed by Teszner, Tzavaras, Gruner, and Hecaen (1972) and Witelson and Pallie (1973). Wada et al. (1975: 245) concluded that "the human brain possesses a predetermined morphological and functional capacity for the development of lateralized hemispheric functions for speech and language."
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B. Clinical case studies The presence of early anatomical asymmetries does not in itself indicate that the two hemispheres function asymmetrically at birth or soon after. Information on cerebral functioning has been contributed by researchers in many different disciplines. One source of information has come from researchers investigating the effect of cerebral damage in infancy and early childhood on language development. Many researchers have found evidence of disruption of language acquisition and cognitive functioning in young children who experienced cerebral damage in early infancy. For example, Annett (1973) found that children who experienced cerebral damage in either hemisphere prior to thirteen months of age showed language impairments, although left-damaged children were more often impaired than those with right damage. A study by Dennis (1977) reports the results of studies with a group of three children who had undergone hemidecortication in early infancy (1 month to 4.5 months). The one right-hemidecorticate child was more language proficient than the two left-hemidecorticates who, in turn, were more proficient at visuo-spatial abilities. These differential effects on language skills as a function of the hemisphere damaged, reinforces the case that the two hemispheres differ early in their development. Two studies (Dennis and Kohn, 1975; Kohn and Dennis, 1974) were conducted on adults who had undergone hemidecortication in late childhood, although their symptoms were noted in infancy. Although all subjects tested had similar verbal IQ scores, their language and cognitive abilities were related to the laterality of the lesion. Dennis and Kohn (1975) studied nine adults who had undergone hemidecortication in childhood (mean: 9.1 years for right-hemidecorticates, 11.5 for left-hemidecorticates). Adults with only an intact left hemisphere were found to perform better and with shorter latencies on some language tasks (e. g., passive negative sentences), relative to adults with only a right hemisphere. Kohn and Dennis (1974) studied visuo-spatial abilities in a group of four adults who had undergone hemidecortication (mean age: 12.2 for right-hemicorticates, 14.0 for left-hemidecorticates). They found that adults with only a right hemisphere, evidenced more ageappropriate visuo-spatial abilities than did adults with only a left
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hemisphere. In a paper published by Dennis and Whitaker (1979), 597 documented cases of childhood hemiplegia were reviewed. The authors conclude that left hemisphere damage and language impairments have a high rate of co-occurrence. The clinical case studies demonstrate that while either hemisphere can develop some level of cognitive competency, language functions are poorer in subjects with only only a right hemisphere, while visuo-spatial abilities are affected in subjects with only a left hemisphere. These deficits are found even in children who have undergone hemidecortication in early infancy. The cerebrum appears to have an inherent pattern for lateralized functioning and there seem to be clear limits to cognitive-linguistic development when there is atypical lateralization.
C. Normal populations Early attempts to assess asymmetrical functioning in early infancy using normal samples have employed a variety of methodologies. Molfese (1972) and Molfese, Freeman and Palermo (1975) used auditory evoked potential response recording procedures to test for the presence of hemisphere differences. The subjects were infants one week to ten months (mean: 5.8 months), children four to eleven years old (mean: 6.0 years), and adults twenty-three to twenty-nine years of age (mean: 25.9 years). Such techniques involve recording the auditory evoked response (AER, a temporally stable, reliable waveform which can be recorded at the scalp) in response to a series of sounds. Such waveforms have been found to be generated by mechanisms within the brain in response to specific external stimuli (Regan, 1972). Molfese (1972) recorded AERs generated over the left and right scalp regions in response to a series of speech syllables (/ba/ and /dae/), monosyllable words (/bi/ and /dog/), a c-major piano chord, and a white noise burst. Differences in the amplitudes of the auditory evoked responses from the left and right hemispheres were found at each age level, even in the young infants. The largest AER amplitude responses to speech stimuli occurred in the left hemisphere while greater amplitude responses to the nonspeech stimuli occurred in the right hemisphere.
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Other researchers employing these techniques have reported similar asymmetrical responding in young infants. Wada and Davis (1977) examined the AERs of sixteen infants aged two to ten weeks (mean: five weeks) to click and flash stimuli. These researchers sought to determine the comparability of infant responses to those of adults who show greater left hemisphere responsiveness to click stimuli and greater right hemisphere responsiveness to flash stimuli. The results showed that thirteen of the infants responded to click stimuli and ten of the infants responded to flash stimuli in a lateralized manner similar to that found in adults. Barnet, de Sotillo and Campos (1974) also recorded AERs from infants in response to click stimuli as well as to speech stimuli (the infants' names). The subjects were normal and malnourished infants under one year of age. Only the normal infants showed larger amplitude left hemisphere than right hemisphere AERs to the speech stimuli. The malnourished infants failed to show greater left hemisphere AER activity to the speech stimuli even after treatment for malnutrition. Interestingly, and contrary to the results reported by Wada and Davis (1977), both groups of infants showed greater AERs to the click stimuli in the right hemisphere. The cause of the discrepant findings of AERs to click stimuli is not clear, though the regions from which the recordings were made differed; Wada and Davis (1977) recorded from occipital and temporal regions while Barnet et al. (1974) recorded from the parietal region. The use of different recording sites might in part account for such differences. Three studies to date have employed the dichotic listening paradigm to examine early hemisphere differences in responsiveness to speech and nonspeech stimuli in infancy. Entus (1977) reported finding hemisphere differences in groups of infants with mean ages of 43.3 to 100 days. The infants were tested using high amplitude sucking as the behavioral response. Pairs of either speech stimuli (/ma/ and /ba/, /da/ and /ba/, /da/ and /ga/) or musical note stimuli executed on different instruments (piano and cello, piano and bassoon, and viola and bassoon) were presented through earphones while the infants sucked on a pacifier. After the continuous presentation of one stimulus pair for a period of time the sucking rate decreased. When a prespecified decrement level in sucking was reached, one stimulus of the pair was changed. Entus (1977) found that the rate of sucking recovered faster if the changed stimulus was a speech sound presented to the right ear (left hemisphere) or a musical sound presented to the left ear (right hemisphere). Although
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Molfese
these results seem to support the notion of early hemisphere differences, the failure of Vargha-Khadem and Corballis (1979) to replicate Entus's (1977) findings for speech, using identical stimuli, response criteria, and equipment, but a somewhat different procedure (the use of a mechanical arm to hold the pacifier in the infant's mouth), leaves the evidence of hemisphere differences based on high amplitude sucking responses equivocal. Glanville, Best, and Levenson (1977) also used a dichotic listening paradigm to study hemispheric differences in infants, but heart rate habituation was used as the response measure. The stimuli were consonant-vowel syllable pairs (Set A: /ba/, /da/, /ga/; Set B: /pa/, /ta/, /ka/) and musical note pairs played on different instruments (Set A: piano, brass, reed; Set B: organ, string, flute). The sets were presented dichotically to infants ninety-three to 130 days old. For eight of the twelve infants, greater recovery from heart rate habituation occurred when novel speech stimuli were presented to the right ear (left hemisphere), while greater recovery occurred when novel musical stimuli were presented to the left ear (right hemisphere). The results of these studies show that infants' electrophysiological and behavioral responses to speech stimuli are greatest when those stimuli are presented to the left hemisphere, while responses to nonspeech stimuli are greatest when presented to the right hemisphere. Since these patterns of responsiveness produced by the infants resemble those of adults, the data have been interpreted as supporting the view that language skills and abilities have as their basis some innate biological component related to brain organization. In the studies described below, further evidence for an innate biological component is presented in studies of language processing. In these studies, data are presented from work with humans, nonhuman primates and nonprimates, which indicate that there are certain speech cues, such as voice-onset-time (VOT), which appear to be processed in a similar fashion across species. Other studies describe research on another speech cue, place of articulation, which appears to be processed in a similar fashion across all developmental periods after birth. Voice-onset-time research Voicing contrast or voice onset time (VOT) reflects the temporal relationship between laryngeal pulsing (e. g., vocal chord vibration)
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and consonant release (e. g., the separation of lips to release a burst of air from the vocal tract during the production of bilabial stop consonants such as /b, p/). Investigators report that adult listeners discriminate changes in VOT only to the extent that they assign unique labels to these sounds (Liberman, Cooper, Shankweiler, and Studdert-Kennedy, 1967). Listeners fail to discriminate between bilabial stop consonants with VOT values of 0 and +20 msec and identify both stimuli as /ba/. Stimuli with +40 and +60 msec VOT are identified as /pa/. While subjects are unable to discriminate between 0 and +20 and between +40 and +60 msec stimuli, they do discriminate between and assign different labels to stimuli with VOT values of +20 and +40 msec. These stimuli are from different phoneme categories (/b/ vs /p/). The 20 msec difference in VOT between speech syllables is only detected when the VOT stimuli are from different phoneme categories. Consequently, changes in VOT appear to be categorical. Such findings are consistently reported with adults in identification and discrimination studies (Liberman, Delattre and Cooper, 1958; Lisker and Abramson, 1964). In the earliest evoked potential study of voicing contrasts, Dorman (1974) used a habituation paradigm. AERs were recorded from scalp electrodes placed over the center of the head (Cz) from fifty adults, ten of whom were assigned to one of five groups. Computer synthesized speech sounds with 250 msec durations were presented at a fixed ISI (1750 msec). Group 1 listened to a series of 20 msec stimuli and then the series was changed to the 0 msec set. On the second day, this group heard first the 20 msec stimuli and then the 40 msec stimuli. Group 2 heard the same stimuli as group 1 but the stimulus order was reversed. Group 3 listened to twenty practice trials of the within category stimulus (0 msec) and the standard (20 msec). A within category shift was then started immediately after pretraining. Group 4 heard stimuli from one category while Group 5 listened to randomly ordered series of stimuli from both within and between phoneme categories. AERs were averaged for the different groups for the different stimuli. The Nl—P2 peak to peak amplitude (Nl range = 75 —125 msec; P2 range = 175 —225 msec) was then measured. The only amplitude effects noted were for AERs elicited by the shift stimuli when they came from a different category than the habituating stimuli. Dorman (1974) interpreted this effect as demonstrating that ERPs could reflect the categorical-like effects of voicing cues.
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Using a different procedure to study VOT, Molfese (1978a) recorded AERs from the left (T3) and right (T4) temporal scalp areas of sixteen adults during a phoneme identification task. Subjects were presented with randomly ordered series of synthesized consonantvowel (CV) syllables which began with bilabial stop consonants varying in VOT values of 0, +20, +40, and +60 msec. Adults were instructed to press one button after each stimulus presentation if they heard a jbj and a second button if they heard a /p/. Adults correctly identified the CV with VOT values of 0 and + 20 msec as /ba/ in approximately ninety-five percent and ninety-three percent, respectively, of the time while the CV with VOT times of +40 and + 60 msec were identified, respectively, ninety-five percent and ninety-eight percent of the time as /pa/. AERs to each stimulus were recorded during the identification task. Subsequent multivariate analyses identified two AER components recorded from the right hemisphere (T4) site, an early negative peak (N110) and a later positive wave (P350) (peak latencies = 110,355 msec, respectively), which varied systematically as a function of the phoneme category of the evoking stimulus. Stimuli with VOT values of 0 and + 20 msec elicited a different AER waveform from the right hemisphere site than did the +40 and +60 msec stimuli. No differences in the AER waveforms were found between the VOT values within a phoneme category (i. e., no differences were found between the 0 and + 20 msec responses or between the +40 and +60 msec responses). These AER patterns of responding were comparable to the behavioral responses given by these subjects during the testing session. Components of the left hemisphere AER differentiated between 0 and + 60 msec stimuli and differentiated the 0 and + 60 msec stimuli from +20 and +40 stimuli. The left hemisphere appeared responsive to the end boundaries of the VOT stimuli but did not reflect the categorical discriminations shown by the right hemisphere. Similar results have also been reported in a study with four-yearold children in which velar stop consonants (/k,g/) were presented (Molfese and Hess, 1978). In this study, AERs were recorded from the left and right temporal regions of twelve nursery-school-age children (mean age = four years, five months) in response to a series of synthesized consonant-vowel syllables which varied in VOT for the initial consonant (0, +20, +40, +60 msec). As with the adults, one AER component from the right-hemisphere electrode site was found to vary systematically as a function of phoneme
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category, but the AER components did not distinguish between VOT values within a phoneme category. A second and distinct (orthogonal) AER component also discriminated VOT values corresponding to phoneme categories. However, unlike that found for adults, this component was present in recording sites over both hemispheres. This evoked potential methodology was extended to include newborn and infant populations (Molfese and Molfese, 1979a). In one study, the four consonant-vowel speech syllables used by Molfese (1978a) were presented to sixteen infants two to five months old (mean age = three months, twenty-five days). Auditory evoked responses to each stimulus were recorded from scalp electrodes placed over the superior temporal regions of the left and right hemispheres. As was found for children, the results showed that one component of the cortical AER from the right-hemisphere site discriminated between VOT values from different phoneme categories. A second component of the AER that responded in a similar fashion was present over both hemispheres. In a separate study (Molfese and Molfese, 1979a), sixteen newborn infants were tested in an attempt to determine the developmental onset of VOT discrimination as reflected in AERs. The same consonant-vowel speech stimuli and recording sites just described were used in the newborn infant study. Results were interpreted to indicate that, whereas both hemispheres were actively involved in the processing of the VOT stimuli, there was no evidence of any phoneme categorical-like VOT effect similar to that found with older infants, children, and adults. The ability to discriminate VOT stimuli along phoneme boundaries appears to be present by two months of age, but may not be present at birth. The absence of such a response at birth suggests that some period of maturation or experience may be required for the VOT categorical perception process to develop or become functional. Non-AER studies involving young infants have also found evidence of categorical discrimination of VOT stimuli. Several different methodologies have been used. Eimas, Siqueland, Jusczyk, and Vigorito (1971) utilized a modification of the High Amplitude Sucking (HAS) procedure in their investigations of VOT perception in one- and four-month-old infants. Six stimuli with VOT values of — 20, 0, +20, +40, +60, and +80 were used. Infants in each age group were assigned to one of two experimental conditions or to a
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Dennis L. Molfese and Victoria J. Molfese
control condition. For infants in the experimental conditions an auditory stimulus was presented repeatedly until the sucking rate habituated (decreased to twenty percent below the criterion sucking level for two minutes). Following habituation, a new auditory stimulus was presented, contingent upon criterion level sucking. Infants in one experimental condition (20D) were presented with VOT stimuli that differed from each other by 20 msec and came from different adult phoneme categories (i. e., +20 and +40 msec). Infants in the other experimental condition (20S) were presented with VOT stimuli that also differed from each other by 20 msec, but the stimuli were from the same phoneme category (i. e., —20 and 0 or + 60 and + 80). Control group infants were presented with one of the six VOT stimuli throughout the testing session with no stimulus change after habituation. Infants in all conditions were found to habituate their sucking rate during repeated presentation of a VOT stimulus. Both the one- and four-month-old infants showed dishabituation of the sucking rate when the stimuli belonged to different phoneme categories (20D) and no dishabituation when the stimuli belonged to the same phoneme category (20S). Control group infants showed no dishabituation. Thus, it appears that infants as young as one month respond to speech sounds varying in VOT in a manner similar to that shown by adults. A subsequent VOT study (Trehub and Rabinovitch, 1972) which also used the HAS procedure also reported that young infants (four to seventeen weeks of age) are able to discriminate between synthesized and natural speech sounds (/b/, /p/, Id/, /t/). Heart Rate (HR) has been used to investigate infant perception of the VOT continuum. Lasky, Syrdal-Lasky and Klein (1975) used HR to study VOT discrimination in infants four to 6.5 months raised in Spanish-speaking homes. These infants had been previously exposed to only a voicing category pattern whose boundaries were somewhat different from those for English speakers. However, in spite of the boundary difference used by their parents, these infants showed a categorical boundary effect comparable to that of English infants and adults. Infants were responsive to differences between — 60 and — 20 msec stimuli and + 20 and + 60 msec stimuli, but not between —20 and +20 msec stimuli. In light of their finding that these infants were found to categorically discriminate between VOT boundaries which are relevant to English but which
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are not relevant to Spanish, Lasky et al. (1975) concluded that VOT perception must have a strong innate component. Using a head turning paradigm, Eilers, Gavin and Wilson (1979) were also able to demonstrate categorical VOT perception in sixto eight-month-old-infants. Interestingly, contrary to the results of the Lasky et al. (1975) study cited above, the Spanish-home infants discriminated both Spanish and English contrasts, while Englishhome infants only discriminated English contrasts. These findings suggest an interactive role for the innate and experiential factors. Taken together, these studies with human infants have demonstrated that the categorical discrimination of speech sounds differing in voicing is present early in infancy and the discrimination does not require extensive experience in producing or listening to those sounds. These results suggested to some authors that the perception of speech sounds might be special to humans (e. g., Eimas, 1974; Morse, 1974), whereas others questioned this position (e. g., Butterfield and Cairns, 1974). Consequently, a number of studies with nonhuman primates were designed to determine if categorical-like discrimination occurs in animals who do not possess the ability to produce the range of human speech sounds. Waters and Wilson (1976) using a shock avoidance paradigm, tested rhesus monkeys on their ability to establish a voiced-voiceless boundary and to discriminate contrasts along that continuum, relative to their boundary. Their results indicated that nonhuman primates place the boundary for /ba-pa/ in the same region as adult human listeners and that discrimination across this consonant boundary (between-categories) was better than within categories. More recently, Kuhl and Padden (1983Z>) have confirmed this finding of categorical discrimination with Rhesus Macaque monkeys using a similar but more extensive set of synthetic speech stimuli that differed in voicing (/ba-pa, da-ta, ga-ka/). A parallel set of findings have been noted with nonhuman primates. Morse, Molfese, Laughlin, Linnville, and Wetzel (submitted) tested a group of fifteen one-year-old Rhesus Macaque monkeys with the same stimuli used by Molfese (1978a). Auditory evoked potentials were recorded from left and right temporal and parietal scalp locations in response to a set of bilabial stop consonants which varied in VOT. Two regions of the AERs (a negative peak at 150 ms and a positive peak at 390 ms) recorded from only the right temporal scalp position were found to discriminate the
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Dennis L. Molfese and Victoria J. Molfese
two voiced from the two voiceless consonants. No within category differences were noted. Thus, it appears that one aspect of human speech perception, categorical discrimination, is observable not only in young infants with minimal exposure to human speech, but also in nonhuman primates, and in some cases even in nonprimates. Results from these studies have been interpreted as evidence that this aspect of speech perception is a property of the primate, if not mammalian auditory system, rather than a specialized mechanism for processing speech (Kuhl, 1979). Place of articulation Evidence of categorical discrimination for a different speech cue, such as place of articulation contrasts, has also been observed in Rhesus Macaques (Kuhl and Padden, 1983a). This evidence, together with evidence of similar discrimination abilities in infants, children and adults also suggests a biologically based ability. Place of articulation refers to the position of portions of the vocal tract during the production of a speech sound. The place cue is important for discriminating between consonants such as jbj and /g/, consonant sounds which are produced in different portions or places of the vocal tract. The consonant /b/ is referred to as front consonant because it is produced in the very front of the vocal tract with the two lips. The consonant /g/, on the other hand, is produced in the back of the vocal tract and is labeled a back consonant. When the following vowel sounds are the same, the second formant transition (a rapid change in frequency) as depicted in a sound spectograph, signals the place of articulation of the consonant. In the case of the syllable /ba/, the second formant transition rises. In the case of the syllable /ga/, the second formant transition falls in frequency. Several studies have been undertaken to identify the electrocortical correlates of acoustic and phonemic cues which are important to the perception of consonant place of articulation information (Molfese, 19786; Molfese, 1980a; Molfese and Molfese, 19796; Molfese and Molfese, 19806). In general, these studies suggest that multiple brain regions working together and separately (which include lateralized and bilateral involvement) are involved in the perception of cues such as second formant (F2) transition and
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formant bandwidth. These findings agree with recent behavioral studies which utilized dichotic temporal processing procedures (Cutting, 1974). Cutting (1974) found that stimuli with speech formant structure or which contained an initial transition element, were better discriminated by the right ear. Since the right ear is thought to have the majority of its pathways projecting to the left hemisphere, Cutting (1974) reasoned that such findings reflected differences in the processing capacities of the two cerebral hemispheres. Molfese (19786) attempted to isolate and localize the neuroelectrical correlates of these cues by presenting a series of computer generated three formant consonant-vowel syllables in which the stop consonants varied in place of articulation (/b, g/). The jbj initial and /g/ initial syllables were identical in all aspects except that the second formant transition rose for the /b/ initial syllable and fell in frequency for the jgj syllable. Other stimulus features varied included formant structure (nonspeech-like formants composed of sinewaves 1 Hz in bandwidth or by speech-like formants with bandwidths of 60, 90 and 120 Hz for formants 1, 2, and 3, respectively), and phonemic versus nonphonemic transitions (the direction of the frequency changes for formant 1 and formant 3 were either rising, so as to produce a phonetic transition in the sense that it could characterize human speech patterns, or these transitions were falling and therefore occured in a manner not found in an initial position in human speech patterns). Using multivariate procedures to isolate major features of the AERs recorded from the left (T3) and right (T4) hemisphere scalp electrode sites of ten adults, Molfese (19786) identified two positive AER components unique to the left hemisphere electrode site which varied systematically in response to changes in F 2 transitions. In a replication and extension of this work, Molfese (19806) also found that electrical activity recorded over the left hemisphere discriminated consonant place of articulation information. In this study, twenty adults were presented with a series of consonant-vowel syllables which varied in the initial consonant, /b, g/, and the final vowel, /i, ae, o/. AERs were recorded from temporal (T3, T4), posterior temporal (T5, Τό) and parietal (P3, P4) scalp locations over each hemisphere. The third positive peak (P460) with its major peak latency at 460 msec was found to reflect the ability of only the left hemisphere to differentiate between the consonants jbj and /g/, independent of the following vowel. A second and earlier occurring positive AER component
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Dennis L. Molfese and Victoria J. Molfese
(peak latency = 170 msec) reflected a similar discrimination by electrodes over both hemispheres. The findings from this last study are important in terms of their implications for the problem of perceptual constancy. Until quite recently (Stevens and Blumstein, 1978), acoustic scientists were unable to isolate a set of acoustic properties that are invariant for a particular consonant place of articulation. Although such invariance exists for vowels, acoustic cues for consonants change as a function of subsequent sounds. Consequently, speech scientists long assumed that consonant and vowel information were processed together as a unit. This electrophysiological study by Molfese (19806) represented the first direct indication that the brain may in fact respond to consonant sound configurations independent of vowel contexts. Two studies by Molfese and Molfese (19796, 19806) attempted to determine at what point in development infants are able to respond differentially to such place of articulation contrasts. In the first study, AERs were recorded from T3 and T4 electrode sites of sixteen newborn infants in response to two stop consonants which differed only in F 2 transition and formant bandwidth. As with adults, one late negative AER component (peak latency = 630 msec) found only over the left hemisphere site differentiated between consonants. A second negative orthogonal AER component (peak latency = 192 msec) was detected by electrodes over both the left and right electrode sites and also distinguished between the stop consonants. The second study (Molfese and Molfese, 19806) sought to determine whether left hemisphere processes are present in the responses of preterm infants and whether these left hemisphere mechanisms are sensitive to phonetic and nonphonetic transitions. Eleven preterm infants (mean conceptional age: 35.9 weeks) were tested after birth. AERs to stimuli identical to those used by Molfese (19786) were recorded again from the T 3 and T 4 electrodes sites over the superior temporal regions of the left and right hemispheres. As found with the full-term newborns, a left-hemisphere process was identified in the AERs of the preterm infants that distinguished between transition cues in stimuli with speech formant structure (bandwidth). An additional AER component recorded over the left hemisphere differentiated between only the nonphonetic stop consonants jbj and /g/. This finding is similar to that reported
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by Molfese (19786) with adults, except for the fact that the lefthemisphere process for adults was sensitive to both phonetic and nonphonetic stimuli. A final factor reflected general hemispheric responsiveness to formant structure differences. This effect was not found for the full-term infants tested by Molfese and Molfese (19796). It is interesting to note that stimuli with speechlike formant structure have yielded differential effects unique to the left hemisphere for infants (Molfese and Molfese, 19796, 19806) but not for adults (Molfese, 19786; Molfese, 1980a). In the former case, the only lateralized effects noted occurred for stimuli with speech formant structure. Stimuli with sine wave formant structure (which have a much narrowed bandwidth) produced no such effect. In the two adult studies, however, the place of articulation contrast effects were noted for stimuli with both speech and nonspeech formant structure. Only bilateral hemisphere effects were noted for formant structure differences. Intriguingly, this is a case where there are developmental changes in lateralized responses in which the early lateralized process appears to disappear with further development. Predictions based on electrophysiology A major issue raised concerning findings of early speech perception abilities in young infants has focused on implications for language development. What, if any, role do abilities to detect VOT boundaries and place of articulation contrasts play in language acquisition? The major aim of a longitudinal study by Molfese and Molfese (1984), carried out between 1978 and 1982, was to identify the relationship between early speech perception abilities of neonates and language development in early childhood. This project attempted to establish the predictive validity of demographic variables, behavioral scales and auditory evoked potentials to place of articulation stimuli for identifying developmental deviations in language abilities. Sixty low-birthweight and normal-weight infants were tested at birth, at six month intervals thereafter until age two years and again at age three years. For each subject the following information was obtained: sex, birthweight, length, gestational age; the ages, income level, education and occupation of both parents; scores on the Obstetric Complications Scale (Littman and Parmelee, 1978); scores on the Brazelton Neonatal Assessment Scale (using scores on each of four a priori
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Dennis L. Molfese and Victoria J. Molfese
dimensions [Als, Tronick, Lester and Brazelton, 1977] and on the overall profile based on ratings for the twenty-six items of the scale); mental subscale scores on the Bayley Scales of Infant Development (Bayley, 1969); and scores on two language tests administered at thirty-six months (the Peabody Picture Vocabulary Test [Dunn, 1965] and the McCarthy Scales of Children's Abilities [McCarthy, 1972]). Auditory evoked responses were recorded at each testing period using scalp electrodes placed over left and right temporal locations (T3 and T4) and referred to linked ears. The auditory stimuli were speech (normal formant) and nonspeech (sinewave formant) synthetic consonant-vowel syllables /bi, bae, bo, gi, gae, go/. These stimuli are described in detail in papers by Cutting (1974) and Molfese (1980a). Stimuli were presented at 80 dB (A) with varied interstimulus intervals, with sixteen random orderings of the twelve stimuli, and were presented while the subjects were quiet and awake. Analyses of the electrophysiological data were developed along four general lines: (1) to identify the electrophysiological response correlates of specific stimulus features; (2) to predict later language performance from brain responses recorded early in development and from behavioral responses; (3) to evaluate the contribution of perinatal and infant variables to the prediction of language performance, and (4) to evaluate the brain responses of infants found to perform normally and subnormally on language tests. 1. Specific stimulus features identified from brain responses The AERs recorded at birth were averaged separately for each stimulus at 8 msec intervals for eighty-eight points (704 msec). These 768 averages (32 subjects χ 12 stimuli χ 2 hemisphere leads) were normalized and then used as input to a principal-components analysis with a covariance matrix and utilizing varimax rotation. Factor analysis of the AER data produced ten factors which accounted for ninety percent of the total variance. Subsequent analyses of variance for Hemisphere χ Consonant χ Vowel χ Formant Structure identified these factors as systematically reflecting hemisphere responses which differentiated between specific speech and nonspeech sounds. Only those factors of the brain waves which were subsequently found to contribute significantly to the predictive models will be described here. A Formant χ Vowel χ Consonant
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interaction characterized Factor 2, and reflected changes in the area of the AER which discriminated the normal formant syllable /bi/ from /gi/. Factor 3 differentiated between the general responses of the left and right hemisphere. A Formant χ Vowel χ Consonant interaction occurred for Factor 8 which discriminated the speech formant structure syllables /bi/ from /gi/ and /bae/ from /gae/. In other analyses of the AER data obtained from six months through three years of age it has been possible to identify correlates of specific stimulus characteristics. Portions of the brain response have been found to discriminate consonant sounds, stimulus bandwidth, and vowel discriminations. Also found, and consistent with earlier published reports (Molfese and Molfese, 1979b, 19806), have been the presence of brain responses reflecting hemisphere differences which are present at birth and continue through thirty-six months of age. 2. Predicting language performance at three years of age from AERs obtained at birth Sixteen infants comprised a subsample of subjects who were available for testing at age three years on the Peabody Picture Vocabulary Scale and on the McCarthy Scales of Children's Abilities. The subsample of subjects did not differ significantly at birth from the corresponding untested subjects on the independent variables under study. The subsample tested at three years of age had mean Peabody scores of 51.0 (SD: 31.9) and mean McCarthy verbal scores of 45.0 (SD: 33.1). Stepwise multiple regression models were constructed using Peabody scores and McCarthy scores as the dependent variables and the AER factor scores obtained at birth for those factors which discriminated between consonant speech sounds (Factors 2, 3 and 8) as the independent variables. One model included the responses of both hemispheres to the syllable /bi/ (Factors 2 and 8) and /gi/ (Factor 8), as well as the hemisphere differences noted for Factor 3. Seventy-eight percent of the total variance was accounted for in predicting McCarthy scores from the brain responses while sixtynine percent of variance was accounted for in predicting Peabody scores. As a test of the internal consistency of this data set and the stability of the findings independent of the principal components-
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Molfese
analysis of variance procedure, classification functions were developed for the averaged AERs based on the digitized time points for each waveform. Results were cross-validated by means of the jackknifed procedure. In this application there were sixteen classes to be discriminated — two subject groups (formed by a median split between the high and low language performers), the two consonant sounds (/b, g/), two formant bandwidths (speech, sinewave), and the two electrode sites (T3, T4). The stepwise discriminant analysis selected two points in order of their effectiveness in classifying each of the original averaged AERs into these sixteen conditions. For the high language group this classification was successful at above chance levels (p < .01) for the LH site for the normal formant /b/ and the normal formant /g/ stimuli. The LH site also correctly classified AERs for sinewave formant jbj and sinewave formant jgj. Significant levels of classification for the low language group occurred for only the normal formant /g/ AERs recorded from the T 4 site. When jackknifed classifications were used, the classification accuracy for the high language group for the four conditions noted above, was still significantly above chance. However, the classification accuracy for the low language group dropped to chance levels. The discriminant function analyses, using discrete AER data points rather than factor scores, correctly classified the same stimuli found to be important in the regression model for the high language group. 3. The contribution of perinatal and infant variables to the prediction of language performance Although the primary focus of this project was to determine the validity of AERs recorded at birth for predicting language performance at age three years, the contributions of the behavioral measures were also assessed. As has been found in earlier studies, correlations between the perinatal variables and the infant and child variables were low. Indeed, few of the correlations reached significance. Significant correlations were found between Brazelton Neonatal Assessment Scale scores and six-month (.41) and twelve-month (.53) Bayley (1969) mental subscale scores. Obstetric Complication Scale scores were significantly correlated with six-month Bayley (1969) mental subscale scores (.66) but not at other ages. The Bayley (1969) mental subscale scores from age eighteen-months on, showed
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stronger correlations with the three-year language measures. The eighteen-month and twenty-four-month Bayley (1969) mental subscale scores significantly correlate .71 and .58, respectively with the thirty-six-month Peabody score. The eighteen- and twenty-fourmonth Bayley scores significantly correlate .63 and .73, respectively with the thirty-six-month McCarthy Scale scores. The Peabody scores and the McCarthey (1972) Scale scores significantly correlate at .64. Demographic characteristics were not significant correlates of infant development and language performance scores. This may be due to the relatively homogeneous nature of the families and infants involved in the study and the small number of characteristics measured. The families were middle class with average incomes of $ 20,00 to $ 25,000, and both parents had at least completed high school. Regression models were constructed to test hypotheses concerning the usefulness of perinatal, demographic and infant development tests to predict language performance at thirty-six months. The models showed that McCarthy scores can be predicted from individual and combinations of the following variables: birthweight, length, gestational age, labor length, eighteen- and twenty-fourmonth Bayley scores and Peabody scores (best full model is birthweight, length, gestational age, eighteen-month Bayley). Peabody scores can be predicted from individual and combinations of the following variables: labor length, Bayley at eighteen and twentyfour-months, McCarthy scales (best models are Bayley-18 and McCarthy, and Bayley-24 and McCarthy). However, the amount of variance accounted for is at best fifty-seven percent. When only birth scores (i. e., BNAS, birthweight, gestational age, length, obstetrical events and complications) were used to predict language scores at three years of age, the regression models were not significant. Regression models were also constructed to test hypotheses concerning the usefulness of all the independent variables (i. e., perinatal, demographic, infant measures and AER factor scores) to predict the language performance scores. The only regression model which was significant involved predicting McCarthy Scale scores from Brazelton scores, Obstetric Complication scores and AER factor scores. This regression model accounts for eighty-one percent of the variance, only three percent more of the variance accounted for using perinatal measures and AER factor scores than was accounted for by using AER factor scores alone.
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4. Brain response differences in high and low language performing children In an effort to identify the specific characteristics of children who show high and low language performance, subsequent analyses were undertaken. In these analyses, a median split was used to separate the children into two groups — those who scored above fifty on the verbal subscale of the McCarthy Scales of Children's Abilities and those who scored below fifty. The perinatal characteristics, as measured by the Obstetrical Complication Scale (Littman and Parmelee, 1978), birthweight, gestational age and Brazelton Neonatal Behavioral Assessment Scale scores of these two groups showed no differences. There were major differences, however, in the newborn infants' brain responses to speech sounds produced by the subjects in these two groups. Only the high language performing group produced brain responses at birth which showed the presence of bilateralized and lateralized processes which discriminated between consonants independent of the following vowel (i. e., /b/ from /g/). While the low language performing group did not produce brain responses which reflected the discrimination of consonants independent of the following vowel, they did discriminate differences between consonants in different vowel environments (i. e., discriminations between /bi/, /bae/, /bo/, /gi/, /gae/, and /go/) in a manner similar to the high language performing group. However, the brain responses of the high language performing infants contained an additional component which reflected discrimination of consonants in different vowel environments. Interestingly, for the high language group, the portions of the brain responses which discriminated between consonants as a function of their vowel environment occurred at later points in time than those which discriminated consonant sounds independent of their vowel sounds. This is the reverse of what has been found with adults. Such adult/ infant differences in the timing of brain responses could reflect maturity differences. However, it is unclear if other variables are also involved. The differential responsivity shown by the high language performance group to the consonants alone and to the consonants in different vowel environments indicates that the nervous system of these infants is more sensitive to the various cues which will later be important to language development. Perhaps, the earlier an
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infant can detect and discriminate between patterns of sounds in his or her language environment, the better able that infant will be to utilize such information as the extensive process of language acquisition begins. Infants who are less responsive or less sensitive to such relevant speech cues would face a more difficult task in mastering the discriminations involved in later word differences. These early discrimination difficulties may be reflected in subsequent language performance at age three years.
Implications The studies reviewed in this chapter provide converging evidence of a biological component subserving language development. The two hemispheres have language-relevant anatomical differences and functional specializations that are present at birth or very early in infancy. The auditory evoked response research provides further support for the notion of a biological influence on brain organization. This biological influence is reflected in part by the ability of a number of specific regions of the brain early in infancy, some of which are bilaterally represented and some of which are lateralized to one cortical region, to discriminate certain acoustic cues which are important for speech perception. Taken together, the evidence presented in this chapter seems to support a view of early language acquisition as dependent, in part, on the maturation and correct functioning of specific acoustic processing mechanisms in the brain which are sensitive to a number of acoustic cues important for speech perception. Infants who have such mechanisms at birth or early in development may consequently be more responsive to their language environment at a number of levels. For example, if an infant's brain can discriminate between two speech sounds, that infant might be more likely to detect such differences and relate them to different objects during word acquisition. Infants whose brains cannot discriminate between such speech sounds would be confronted by a certain level of confusion in attempting to relate one sound sequence to a variety of different objects or actions which are normally associated with two different sound sequences. Infants who are better equipped to discriminate a variety of speech sound cues would be expected to show better development in terms of
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earlier acquisition of specific words than would infants who could not make those discriminations, or who had greater difficulty in discriminating those sounds. This difference in acquisition rate could persist into the preschool years. This speculation, we believe, receives support from the results of our longitudinal research project (Molfese and Molfese), which showed that infants whose AERs at birth reflected differential processing of the place of articulation speech cues later performed differently on tests of language development. Further support comes from research reports that difficulties in making fine temporal discriminations and/or problems in processing rapidly changing acoustic information also influence language development (Tallal and Percy, 1973; Tallal and Newcomb, 1978; Tallal, Stark, Kallman and Mellits, 1981).
Conclusion The present study reviews evidence from various methodologies including anatomical procedures, work with brain-damaged populations and electrophysiological procedures, all of which point to the early specialization during infancy of the cerebral hemispheres for language. The evidence from electrophysiological research involving two speech cues (place of articulation and voice-onset-time) show early asymmetries that are multidimensional and show developmental changes with increasing age. Some of these electrophysiological responses are stable enough in infancy to be useful in predicting language performance in childhood. These findings should not be taken as an indication that language abilities are all innate; there does seem to be evidence that some language abilities (such as the perception of some speech cues) are present at birth, while others seem to require some period of time to develop. References Als, Η., Ε. Tronick, Β. Lester, and Τ. Brazelton 1977 The Brazelton Neonatal Behavioral Assessment Scale (BNBAS). Journal of Abnormal Child Psychology 5. 215 — 231. Annett, M. 1973 Laterality of childhood hemiplegia and the growth of speech and intelligence. Cortex 9. 4—33.
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Barnet, Α., Μ. de Sotillo, and Μ. Campos 1974 EEG sensory evoked potentials in early infancy malnutrition. Paper presented at the meeting of the Society for Neurosciences, St. Louis, Missouri. Bayley, N. 1969 Bayley Scales of Infant Development. New York: The Psychological Corporation. Butterfield, E., and G. Cairns 1974 Discussion summary: Infant reception research. In R. Schiefelbusch and L. Lloyd (eds.), Language Perspectives: Acquisition, Retardation and Intervention. 75 — 102. Baltimore: University Park Press. Cutting, J. E. 1974 Two left hemisphere mechanisms in speech perception. Perception and Psychophysics 16. 601—612. Dennis, M. 1977 Cerebral dominance in three forms of early brain disorder. In M. Blaw, J. Rapin, and M. Kinsbourne (eds.), Topics in Child Neurology. 189 — 212. Bloomington, Indiana: Spectrum. Dennis, M., and B. Kohn 1975 Comprehension of syntax in infantile hemiplegics after cerebral hemidecortication: Left hemisphere superiority. Brain and Language 2. 472-482. Dennis, M., and H. Whitaker 1979 Hemispheric equipotentiality and language acquisition. In S. Segalowitz and F. Gruber (eds.), Language Development and Neurological Theory. 93 — 104. New York: Academic Press. Dorman, M. 1974 Auditory evoked potential correlates of speech sound discrimination. Perception and Psychophysics 15. 215 — 220. Dunn, L. 1965 Peabody Picture Vocabulary Test. Circle Pines, Minn.: American Guidance Service. Eilers, R., W. Gavin, and W. Wilson 1979 Linguistic experience and phonemic perception in infancy: Across longitudinal study. Child Development 50. 14 — 18. Eimas, P. 1974 Auditory and linguistic processing of cues for place of articulation by infants. Perception and Psychophysics 16. 513 — 521. Eimas, P. D., E. Siqueland, P. Jusczyk, and J. Vigorito 1971 Speech perception in infants. Science 171. 303 — 306. Entus, A. 1977 Hemispheric asymmetry in processing of dichotically presented speech and nonspeech stimuli by infants. In S. Segalowitz and F. Gruber (eds.), Language Development and Neurological Theory. 63 — 73. New York: Academic Press. Geschwind, Ν., and W. Levitsky 1968 Human brain: Left-right asymmetries in temporal speech regions. Science 161. 186-187.
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Glanville, B., C. Best, and R. Levenson 1977 A cardiac measure of cerebral asymmetries in infant auditory perception. Developmental Psychology 13. 54—59. Kohn, B., and M. Dennis 1974 Selective impairments of visuo-spatial abilities in infantile hemiplegics after right cerebral hemidecortication. Neuropsychologia 12. 505 — 512. Kuhl, P. 1979 Speech perception in early infancy: Perceptual constancy for specifically dissimilar vowel categories. Journal of the Acoustical Society of America 66. 1668-1679. Kuhl, P., and D. Padden 1983a Enhanced discriminability at the phonetic boundaries for the place feature in macaques. Journal of the Acoustical Society of America 73. 1003-1008. 1983ft Enhanced discriminability at the phonetic boundaries for the voicing features in macaques. Perception and Psychophysics 32. 542—550. Lasky, R. E., A. Syrdal-Lasky, and R. Klein 1975 VOT discrimination by four to six-and-a-half month old infants from Spanish environments. Journal of Experimental Child Psychology 20. 213-220. Lenneberg, Ε. 1967 Biological Foundations of Language. New York: Wiley. Liberman, A. M., F. S. Cooper, D. Shankweiler, and M. Studdert-Kennedy 1967 Perception of the speech code. Psychological Review 74. 431—461. Liberman, A. M., P. C. Delattre, and F. S. Cooper 1958 Some cues for the distinction between voiced and voiceless tops in initial position. Language and Speech 1. 153 — 167. Lieberman, P. 1977 Speech Physiology and Acoustic Phonetics. New York: Macmillan. Lisker, L., and A. S. Abramson 1964 Across language study of voicing in initial stops: Acoustical measurements. Word 20. 384-422. Littman, B., and A. Parmelee 1978 Medical correlation of infant development. Pediatrics 61. 470 — 474. McCarthy, D. 1972 Manual for the McCarthy Scales of Children's Abilities. New York: Psychological Corporation. Molfese, D. L. 1972 Cerebral Asymmetry in Infants, Children and Adults: Auditory Evoked Responses to Speech and Music Stimuli. Doctoral dissertation, Pennsylvania State University. Dissertation Abstracts International, 33. University Microfilms No. 72—48, 394. 1978a Neuroelectrical correlates of categorical speech perception in adults. Brain and Language 5. 25 — 35. 1978ft Left and right hemisphere involvement in speech perception: Electrophysiological correlates. Perception and Psychophysics 28. 237 — 243.
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Hemispheric specialization for temporal information: Implications for the perception of voicing cues during speech perception. Brain and Language 11. 285-299. 19806 The phoneme and the engram: Electrophysiological evidence for the acoustic invariant in stop consonants. Brain and Language 9. 372 — 376. Molfese, D. L., R. B. Freeman, and D. S. Palermo 1975 The ontogeny of brain lateralization for speech and nonspeech stimuli. Brain and Language 2. 356—368. Molfese, D. L., and T. Hess 1978 Hemispheric specialization for VOT perception in the preschool child. Journal of Experimental Child Psychology 26. 71—84. Molfese, D. L., and V. J. Molfese 1979a VOT distinctions in infants: Learned or innate? In H. A. Whitaker and H. Whitaker (eds.), Studies in Neurolinguistics. Vol. 4. 225 — 238. New York: Academic Press. 19796 Hemisphere and stimulus differences as reflected in the cortical responses of newborn infants to speech stimuli. Developmental Psychology 15. 505-511. 1980Z» Cortical responses of preterm infants to phonetic and nonphonetic speech stimuli. Developmental Psychology 16. 574—581. 1984 Prediction of preschool language performance based on perinatal variables. In R. Dillon (ed.), Individual Differences in Cognition. Vol. 2. 95 — 117. New York: Academic Press. (In press). Electrophysiological indices of auditory discrimination in newborn infants: The bases for predicting later language development? Infant Behavior and Development. Morse, P. 1974 Infant speech perception: A preliminary model and review of the literature. In R. Schiefelbusch and L. Lloyd (eds.), Language Perspectives: Acquisition, Retardation and Intervention. 195 — 227. Baltimore: University Park Press. Morse, P., D. Molfese, N. Lauglin, S. Linnville, and F. Wetzel (submitted). Categorical perception for voicing contrast in normal and lead-treated rhesus macaques: Electrophysiological indices. Paper available from the first author. Regan, D. 1972 Evoked Potentials in Psychology, Sensory Physiology and Clinical Medicine. New York: Wiley. Segalowitz, S. 1983 Language Functions and Brain Organization. New York: Academic Press. Segalowitz, S., and F. Gruber 1977 Language Development and Neurological Theory. New York: Academic Press. Stevens, K., and S. Blumstein 1978 Invariant cues for place of articulation in stop consonants. Journal of the Acoustical Society of America 64. 1358 — 1368.
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Tallal, P., and M. Piercy 1973 Developmental aphasia: Impaired rate of nonverbal processing as a function of sensory modality. Neuropsychologia 11. 389—398. Tallal, P., and F. Newcombe 1978 Impairment of auditory perception and language comprehension in dysphasia. Brain and Language 5. 13—24. Tallal, P., R. Stark, C. Kallman, and D. Mellits 1981 A re-examination of some nonverbal perceptual abilities of language impaired and normal children as a function of age and sensory modality. Journal of Speech and Hearing Research 24. 351 —357. Teszner, D., A. Tzavaras, J. Gruner, and H. Hecaen 1972 L'asymetrie droit-gauche du planum temporale: A propos de l'etude anatomique de 100 cerveaux. Revue Neurologique 126. 444 — 449. Trehub, S., and S. Rabinovitch 1972 Auditory-linguistic sensitivity in early infancy. Developmental Psychology 6. 74 — 77. Vargha-Khadem, F., and M. Corballis 1979 Cerebral asymmetry in infants. Brain and Language 8. 1—9. Wada, J. 1969 Interhemisphere sharing and shift of cerebral speech function. Excerpta Medica International Congress Series 193. 296 — 297. Wada, J., R. Clarke, and A. Hamm 1975 Cerebral hemispheric asymmetry in humans. Archives of Neurology 32. 239-246. Wada, J., and A. Davis 1977 Fundamental nature of human infant's brain asymmetry. Le Journal Canadien des Sciences Neurologiques 4. 203—207. Waters, R., and W. Wilson 1976 Speech perception by rhesus monkeys: The voicing distinction in synthesized labial and velar stop consonants. Perception and Psychophysics 19. 285-289. Witelson, Α., and W. Pallie 1973 Left hemisphere specialization for language in the newborn: Neuroanatomical evidence of asymmetry. Brain 96. 641 — 647.
Primate communication, comparative neurology, and the origin of language re-examined Horst D. Steklis
Abstract The view that nonhuman primates lack significant voluntary control over their vocalizations and that their vocalizations lackpropositional, referential, or symbolic qualities has been a persistent one, especially among those who have examined the evolutionary origin of human speech. This view would seem tofavor proposals of human language having originated in the form of manual gesture, a modality that in nonhuman primates appears to be subject to greater voluntary control. Recent field and laboratory investigations of the information conveyed in the natural vocalization system of primates and comparative neurological data, however, point to important similarities between the vocalization system of nonhuman primates and human speech. In particular, use of innovative methodology such as the "playback" technique has shown in several New and Old World monkey species that calls convey more than the sender's emotional-motivational state, including also information about the sender's sex, group membership, and social relationships. In some species, calls apparently also have semantic qualities, in that they encode specific information about external objects or events, and there is evidence that the decoding of calls may be governedby simple syntactical rules and that perceptual mechanisms similar to those in human speech may be employed. This structural andfunctional complexity of calls is also reflected at the level of governing neural mechanisms. Not only is there strong evidence for volitional components in calls and the involvement of neocortical mechanisms, but there may also be a differentiation of neural control mechanisms according to call type. Furthermore, in some species hemispheric asymmetries exist in auditory perception and perhaps also production of calls. Despite the absence of significant neurobiological data from apes, these data suggest that the vocal-auditory machinery of the earliest hominids was far more ready to take on "primordial" speech functions than has been previously supposed.
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1. Introduction When nearly a decade ago I began to give the question of language origins serious attention, I was convinced, like many others pondering this problem, that there were no particularly appealing or promising similarities between human speech and the natural communication systems of nonhuman primates. Indeed, the chasm separating human language from nonhuman communication appeared so great that any speculation on the evolution of language had to consider how qualitatively new perceptual, cognitive, and motor abilities arose in the human lineage. In very simple terms, the information content of nonhuman communication signals was believed to be relatively poor and the repertoire a genetically fixed, closed one (cf. Hockett, 1960). Unlike human language, the signals of other species informed only about the signaller's location and emotional-motivational state, such as hunger, fear, or sexual arousal. In this view, such signalling behavior lacks the propositional, referential, and symbolic features that are an integral part of human language. It appeared that continuities between humans and other primates were confined to nonverbal expression and certain paralinguistic phenomena, like moans and yells, or the pitch and intensity of speech. Most importantly, neurobiological data seemed to buttress this formulation. Monkey or ape calls and facial expressions were apparently mediated by the very subcortical and paleocortical limbic structures that played a primary role in the regulation of affect, of which the natural calls and gestures were an involuntary expression. It is well-known that human language, by contrast, relies substantially on neocortical mechanisms. It is no wonder that in this light the achievements of chimpanzees in the laboratory seemed odd. Why should the ape whose natural communication system contains no language-like elements be capable of representational thinking or of appreciating man-made symbols? It is noteworthy that various attempts to explain such cognitive abilities of apes have addressed behaviors in the wild not strictly involving use of the face or voice, such as the complexity of social interaction in general (Humphrey, 1976) or manual gesture (Plooij, 1978). And it is, of course, the observation of the richness of manual gesture shown by feral chimpanzees along with their capacity to learn elements of sign language that has made theories of human
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language as originating in manual gesture so specially attractive (Hewes, 1973; Steklis and Harnad, 1976). In the last few years there have been significant advances in the analysis of the structure and function of monkey vocalization in the wild and in the lab which, I believe, provide sufficient cause for reassessing our view of monkey vocalization in relation to human speech (see Snowdon et ai, 1982, and Byrne, 1982, for recent reviews). Similarly, the now very active investigation of both perceptual and motor mechanisms of monkey vocalization are beginning to reveal a far greater complexity than we had previously realized, and the possibility is now emerging that many of the differences between human and nonhuman primate communication are ones of degree rather than kind (see Steklis and Raleigh, 1979a, for review). Clearly, how we view ourselves as different from other primates will have direct bearing on any models of human origins, including those concerning the origin of language. My present purpose will be to describe some of the progress that has been made in the study of primate vocalizations in terms of their social function and neural control, and to evaluate the significance of recent studies for speculations on the origin of human speech.
2. Structure and function of primate vocalization It is now clear that until very recently our understanding of both the structure and function of primate calls was limited not so much by our imagination as by our analytic devices. Prior to the 1970s the emphasis in primate field studies, for example, was on description and cataloguing: the human ear, tape recorder, and sound spectrograph were the principal analytic tools. These made possible the classification of calls according to type, both in terms of physical and contextual features, and systematic comparison of vocal repertoires. These analyses still provide the major means for determining the structure and function of primate vocalization in relation to both the social and the ecological contexts (e. g., Green, 1975; Marler, 1973). Among the most significant developments in recent years has been the introduction of new experimental techniques in field and laboratory. In particular, the "playback" technique has provided a
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number of fresh insights into the nature of primate vocalization. As the name suggests, this technique involves the documentation of the animals' responses to their own previously recorded vocalizations played back through a concealed loudspeaker. In this case, the monkeys, appropriately so, and not the experimenters, are the perceivers who inform us about the meaning of the vocalization. There are two pertinent results of this research. The first indicates that primate vocalizations contain far more information than we had previously realized, and the second shows that some species perceive their vocalizations in ways not readily apparent to us. As we shall see, both findings should lead us to re-evaluate the traditional view of human/nonhuman differences in vocal abilities as set forth earlier. That substantial individual variability exists in the form of primate calls has been known for some time in both monkeys and apes (Rowell and Hinde, 1962; Marler and Hobbett, 1975). However, it has not been clear until recently that conspecifics are sensitive to and make use of such variation. Playback studies show this to be the case. Variation in calls apparently informs of the sender's sex, group membership, and social relationships. Japanese macaque mothers show selective responses to playbacks of recorded vocalizations of juveniles. They respond much more vigorously to the coos of their own offspring than to those of unrelated juveniles (Pereira and Bauer, 1978). Similarly, squirrel monkey mothers are more responsive to their own infant's vocalizations than to those of other infants (Kaplan et al., 1978). Differences in the calls of rhesus monkey mothers are also responded to selectively by their juvenile offspring (Hansen, 1976). In a recent field experiment Cheney and Seyfarth (1980) played "lost" calls of infants to groups of mothers, all of whose infants were out of sight, and found that mothers responded selectively to calls of their own infants. Interestingly, other mothers were quite aware of whom the infants were related to, as recorded calls of other infants caused them to look at the infant's mother. A playback experiment using chimpanzee panthoot calls and control sounds showed that chimpanzees discriminate between calls of familiar and strange animals as well as between male and female pant-hoots (Bauer, 1978). A similar study of freeranging forest mangabeys revealed that groups respond selectively to differences in the long-distance calls of adult males from different groups (Waser, 1977). Finally, in their study of pygmy marmoset
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contact calls, Snowdon and Cleveland (1980) found individually distinctive acoustic features in the calls, which elicited differential individual responses upon playback. In some ways these results are not so surprising. One might well expect that intelligent, long-lived primates, who spend most of their lives in close proximity to relatives and fellow group members, would readily learn to associate individual vocal characteristics with other attributes of social relevance. This is similar to our attention to the paralinguistic elements of human speech, which can identify a person's age, sex, or place of origin. More interesting, then, would be the discovery of linguistic elements in primate vocalization. As stated earlier, the long-held view has been that primates communicate primarily about internal states and say relatively little or nothing about external objects or events, so typical of human language. Thus, a common distinction that is made is between affective and semantic types of communication. A series of recent field experiments have seriously challenged such distinctions. Since the early field descriptions by Struhsaker (1967) in the midsixties, vervet monkey calls have held the interest of primatologists concerned with the origin of language (e. g., Lancaster, 1968). The reason for this is that they give acoustically different alarm calls to at least three types of predators (to large mammalian carnivores like leopards; to eagles; and to snakes such as pythons), and each call type is associated with an adaptively appropriate escape response (e. g., when on the ground, leopard calls cause the monkeys to seek refuge in the trees, whereas snake calls cause them to search the ground). This rare form of alarm call thus seems to convey information about the physical environment, in a manner highly similar to human naming. Seyfarth et al. (1980) tested this possibility by playing back recorded alarm calls to free-ranging vervets in the absence of actual predators and filming the monkeys' responses. Alarm-call playbacks resulted in subjects' looking in the direction of the concealed loudspeaker and responding to each type of call with an appropriate escape response, indistinguishable from those that had been witnessed in response to the actual predators. Analysis of the filmed material also revealed that individuals largely responded independently of one another, that is, without first looking at another monkey that had already begun to respond. Interestingly, infants were the ones most likely to look at others first. Furthermore,
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alarm-call class specific responses were elicited regardless of the sender's or responder's age or sex, and response type was not affected by manipulation of length or amplitude of the played-back calls. Differential responses to variations in call length or amplitude, which mirror arousal level, would be expected if it were degree of arousal that was primarily communicated by the calls. As the experimenters have pointed out, it is hard to escape the conclusion that some vervet monkey calls have semantic qualities, in the sense that they encode information about classes of things in the external environment. But is this a unique, rather specialized ability that is confined to this class of vocal behavior? Seyfarth and Cheney (1982) suggest that the first appearance of even rudimentary representational signalling is likely to confer such considerable selective advantage to its users as to encourage use of this ability in a broad variety of social and ecological contexts. More recent field experiments on vervet monkeys by the same investigators (Cheney and Seyfarth, 1982) confirm this prediction. Again, through use of the playback technique, they investigated the information contained in vervet "grunt" vocalizations. The "grunt", which humans perceive as one type of call, is acoustically highly variable and is perceived by the monkeys as at least four distinct types of call. Grunts are given in a number of social contexts, but it appears that each grunt type conveys specific information independent of context. Grunts recorded from several distinct social contexts (e. g., dominance interactions, movement into an open area, sight of another group) were each played back under a variety of social and environmental circumstances. Differential responding was determined by measuring from film the duration and latency of looking at or away from the speaker or in the direction the speaker was facing. Different grunt types did produce such differential responding regardless of the context in which they were played. For example, upon hearing a grunt originally given by a group member as it approached a dominant monkey, subjects looked significantly longer at the speaker than when they heard a grunt originally given by a group member watching another move into an open area. It is noteworthy that while grunts given to a dominant resulted in orientation toward the speaker, a grunt type given in response to sighting another group resulted in looking in the direction the speaker was pointed. Subjects did not look at the group member from which the grunt had been recorded (which would
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have been difficult under any circumstance as great care was taken to play calls only when animals whose recorded calls were used were not visible). Although, unlike the predator alarm calls, the variation in grunts is more subtle and the differential responding is more of a quantitative nature, these results do suggest that grunts too encode specific information about external objects or events, such as the presence of another group. Meaningful variations in what seem to us to be a single call have been described for other primate species as well, and hence what has been found in vervet monkeys may represent a more general phenomenon. The now well-known study by Green (1975) on Japanese macaque "coo" calls clearly shows that this is not one type of call but several which are emitted in different social contexts. Playback experiments are needed in this case to tell us more about the information contained in these variants of the coo call. There is further evidence to confirm Seyfarth and Cheney's (1982) prediction that representational vocal signalling may be widespread among nonhuman primates. By employing playback procedures comparable to those of Seyfarth et al. (1980), Gouzoules et al. (1984) demonstrated that agonistic screams of free-ranging rhesus monkeys on Cayo Santiago (Puerto Rico) refer to external objects and events by conveying information about the nature of an agonistic encounter. In the first phase of the study, Gouzoules et al. identified five acoustically distinct types of screams that serve to recruit support from allies (usually out of visual contact) against opponents during agonistic encounters. Contrary to earlier beliefs that such calls intergrade with one another, pari passu with the level of arousal of the caller, they found each of the five types of calls to be relatively discrete. An analysis of the social contexts in which the screams were given indicated that each carried a different message by designating different types of opponents (e. g., higher- or lower-ranking, kin or non-kin) and level of physical aggression. This was confirmed by playback experiments, in which examples of different screams recorded from immature animals were played back to their mothers. As predicted, the latter's responses (latency to and probability and duration of looking in the direction of the concealed speaker) varied according to call type. Finally, Dittus (1984) has presented evidence for semantic properties of food calls among wild toque macaques (Macaca sinica). On the rare occasions when group members discover a large
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quantity of food in the forest they give a distinctive loud, high pitched "whee" call for 5 — 10 minutes, which quickly brings dispersed group members to the site. Animals typically respond to the call (whose source was usually well hidden from view) by stopping current activity, orienting to the source of the call, and running there to feed. As no calls were given when, for example, the same food source was encountered with a large quantity of unripe food that was not eaten, the calls apparently communicate about common properties like high food abundance and palatability rather than about particular foods. This is also clear from a description by Dittus of an interesting variation in the context of the food call: one group who fed habitually at a municipal garbage dump responded with the same food call to the engine noise of the particular tractor approaching and depositing refuse at the dump, while the engine noises of other tractors were ignored. Because the food calls elicit the same response from group members as coming into direct contact with the food source itself, Dittus quite reasonably concludes that the calls are semantic signals that denote a source of abundant food. A number of recent studies, employing innovative techniques, have been conducted to determine which acoustic dimension(s) monkeys find salient in decoding their vocalizations. Some of this research has been inspired and guided by the well-known finding that certain acoustically continuous human speech sounds are perceived categorically. By presenting monkeys with synthesized calls, in which a particular acoustic dimension is systematically varied, it has recently been possible to show that some species also perceive elements of their graded vocal signals in a categorical fashion (Petersen, 1982, for review). By now best known is the study by Petersen and colleagues on two variants of the Japanese macaque coo call, which according to Green's field study are emitted in different social contexts. Acoustically, these two variants grade into one another; however, Japanese macaques, but not other Old World monkey species, selectively attend to the relative peak fundamental frequency position in discriminating between the two calls. In an operant conditioning task, the two variants were treated as different when the peak position occurred along a narrow boundary in synthesized calls. No such boundary effect was apparent when pitch was varied. Japanese predator alarm and estrous calls, which fall into an acoustically graded continuum, but normally elicit distinctly
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different responses (flight vs approach), are also perceived categorically by a subpopulation of this species (Masataka, 1983a). Playback experiments, employing synthesized calls, showed that the behavioral response patterns of free-ranging Arashiyama West group members changed distinctly with a slight difference in one parameter (end frequency) of the alarm call. The same call variants, however, were perceived continuously by members of the Arashiyama East group, who rarely emit alarm calls because they rarely encounter predators. As Masataka suggests, this population difference in perceptual processing strategies (categorial vs continuous) appears to be a learned phenomenon linked to environmental differences (presence or absence of predators) perhaps analogous to that seen among human language communities. Categorical perception of continuous variations in pygmy marmoset trill calls is suggested by the results of Snowdon and Pola (1978), who showed that, when the duration of synthetic trills was varied, subjects responded differently (i.e., with the presence or absence of antiphony) across a sharp boundary in duration. The boundary apparently corresponds to the functionally distinct closed and open mouth trill calls. Finally, Masataka (19836) demonstrated categorical perception of predator alarm calls played back to captive Goeldi's monkeys (Callimico goeldii). In the wild, different types of alarm calls are associated with different types of predators, and the behavioral responses vary with call type (Masataka, 1982). The two most consistent types of responses to naturally occurring alarm calls in the field and to calls played back in the laboratory were freezing and emission of warning calls. Playback of synthesized calls varying in frequency range produced differential behavioral responding across a narrow acoustic boundary, suggesting an underlying perceptual boundary. As both Petersen (1982) and Snowdon (1982) have recently pointed out, the combination of continuous and categorical perceptual strategies in the discrimination of Japanese macaque coo calls and the categorical perception of trills by marmosets appear to be closely analogous to the manner in which humans perceive speech. As such, the above findings further reinforce the emerging view of monkey vocalizations as highly complex in both structure and information content. Monkey calls may also be similar to human speech at a further level of complexity, namely, in showing a simple form of syntax.
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In the wild, Titi monkeys repeat calls to form phrases and combine these to form sequences (Robinson, 1979). Different sequence types varied in proportion in different contexts. Apparently, the order of these phrases encodes meaning, as artificially ordered playbacks evoked different behavioral responses. Cotton-top tamarins also emit such vocal compounds, in which the function of the compound is equal to the sum of the functions of the individual units (Cleveland and Snowdon, 1982). Clearly, this is syntax at a very simple level, and the conservative linguist may feel that the term has lost its meaning if extended to such phenomena. My primary purpose here has not been to prove that monkey calls are like human speech in so many ways, but simply to draw attention to the fact that they are far more complex than we had previously realized in both the type of information conveyed and the nature of the decoding processes employed. No one would disagree that whatever abilities have been shown pale by comparison to human language. Many, however, would argue (see Snowdon et ah, 1982) that the demonstration of even crudely comparable features, such as the ones reviewed here, gives credibility and substance to a comparative psycholinguistic approach. Certainly, the chasm between human and nonhuman communication is not as wide as was previously believed and some tenuous bridges are beginning to emerge.
3. Neural mechanisms of call production and perception As I mentioned at the outset, the view of a behavioral dichotomy has often been extended to include the neural machinery of primate communication. Historically, the idea that monkey and ape calls are regulated by (largely subcortical) limbic formations has become linked to the idea that calls lack a volitional component. In some respects this association stems from a dated view of encephalization and cortical functioning, in which more recently evolved and elaborated functional capacities (like speech) are seen as becoming more completely controlled by rostral neocortical machinery. Modern studies of nervous system evolution and function, however, indicate that the brain did not evolve by a simple "upstairs" shifting of
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functions, but rather systems become reorganized as a whole. For example, the primate visual system did not evolve by a simple shifting of visual functions to the cerebral cortex; major changes occurred in thalamic relay nuclei and other subcortical areas (e. g., Allman, 1977). Similarly, while the human neocortex plays a substantial role in speech production, so do a number of related subcortical areas (Ojemann, 1983). I am certainly not aware of any evidence showing that the neocortex is the seat of volition. Therefore, the adherence to a strict dichotomy (i. e., limbic or subcortical and involuntary vs neocortical and voluntary) in the neural regulation of nonhuman vs human vocalization (e.g., see Myers, 1976) would seem to be of very limited utility. Recent evidence, which I will review below, shows clearly that all monkey calls are not simply involuntary expressions regulated by subcortical structures. Rather, like human speech, monkey calls are complex structurally and functionally (e. g., syntax and semanticity, see section 2), which appears to be reflected at the level of governing neural mechanisms. Available evidence points not only to the existence of volitional components in calls but also to the possible existence of a differentiation of neural mechanisms according to call type. Furthermore, as in speech, hemispheric asymmetries exist with regard to auditory analysis and perhaps also production of calls. Major gains have been made in recent years in our understanding of the neural mechanisms of vocal production and auditory decoding, largely because of intense efforts to integrate knowledge of how vocal systems function in nature with neurobiological analysis. Unfortunately, however, this integration between the neurobiologist's and the naturalist's approaches to the problem of vocal regulatory mechanisms is very recent. Thus, the preponderance of neurobiological data are from the squirrel monkey, whose vocal system in the wild is little understood, while relatively fewer neurobiological data are available for the macaque, whose vocal system is much better understood. More regrettable is the fact that essentially nothing is known about the neural mechanisms of vocal performance in species most closely related to humans (i. e. the African apes), who by virtue of their close phylogenetic position to us may share with humans many neurobiological features (e. g., as in the case of morphological cerebral asymmetries, LeMay et al., 1982).
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The majority of the neurobiological data have been obtained through use of traditional brain lesioning and stimulation techniques. Most studies have examined the effects of these procedures on spontaneous call frequency, but a few have also looked at the effects on learned phonation. This distinction between spontaneous and learned (or voluntary) vocal performance turns out to be an important one in the evaluation of underlying neural mechanisms. In clinical neurology, a similar distinction between automatic and propositional speech has served well, in that neural lesions, for example, may differentially affect these aspects of speech. What is the evidence for a voluntary component in monkey vocalization? The best demonstration of this has come from discriminative conditioning studies. Very simply, in such experiments monkeys have to learn to emit a vocalization of given amplitude and duration in response to an arbitrary stimulus and withhold vocalization in response to a second arbitrary stimulus in order to get food and in some instances to avoid punishment. Although some early attempts to condition vocalizations failed (see Myers, 1976, for review), several recent experimenters, using the same species (the rhesus macaque) have found that such discriminative vocal behavior is no more difficult to obtain under these training conditions than is a manual lever press response (Sutton et al., 1981a; Sutton, 1979, for review). While admittedly we cannot know for certain with this or any other technique that monkeys are exercising volitional control over vocalization, it would certainly be surprising if they lacked this ability altogether, given their performance in these experiments as well as in the wild. The suggestion by Green (1975) that the localespecific variants in the tonal theme of clear (coo) calls among freeranging groups of Japanese macaques represent learned dialects, and the observation by Seyfarth and Cheney (1980) that young vervet monkeys gradually restrict the variability of their predator alarm calls by closely attending to their mothers, both imply some degree of vocal learning ability. In their review of developmental factors in nonhuman primate vocalization, Newman and Symmes (1982) suggest that the primary role of learning in acoustic behavior of primates may be to gradually restrict with age the variability of calls as well as the behavioral responses to them. Experimental brain studies strongly reinforce these behavioral observations. Several cerebral areas play a role in voluntary call
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production. Among these, the anterior cingulate gyrus, commonly considered limbic cortex, is of critical importance. Lesions of this area selectively abolish operantly conditioned calls in rhesus monkeys (Trachy et al., 1981), while frequency of spontaneous vocalization is unimpaired in both rhesus and squirrel monkeys (Kirzinger and Jürgens, 1982). Interesting from the present standpoint is the recent exploration of a neocortical area that lies above the cingulate gyrus on the medial wall of the cerebral hemisphere. Kirzinger and Jürgens (1982) have found that in the squirrel monkey bilateral ablations of this area selectively reduce the number of spontaneous isolation peeps while other call types remain unaffected. They cite unpublished results from a single unit recording study by Sutton in the rhesus monkey, which show that activity of neurons in this region, as in the anterior cingulate cortex, is correlated with call initiation in an operant conditioning task. Evidently in humans this neocortical region is considered as part of the supplementary motor area, which when damaged results in deficits in the spontaneous initiation of speech (evidence reviewed in Kirzinger and Jürgens, 1982). In humans free of brain lesions, cerebral blood flow studies indicate that complex sequential voluntary movements activate the supplementary motor area (Orgogozo and Larsen, 1979). Thus, as suggested by Kirzinger and Jürgens (1982), this part of the neocortex is very likely also involved in volitional control of nonhuman primate Phonation. In particular, the squirrel monkey isolation peep may have a stronger volitional component than other call types that are not affected by lesions of this area (Kirzinger and Jürgens, 1982). Newman and MacLean (1982) have proposed that the isolation peep is functionally similar to the macaque coo call, in that both serve to bring animals into social contact when isolated. Given that in macaques these calls are easily conditioned and that in the wild they may be subject to learned modification (Green, 1975), this class of calls may be special in both squirrel and macaque monkeys in terms of behavioral plasticity and neural regulatory mechanisms (e. g., see Newman and MacLean, 1982). Thus, in the case of monkey vocalizations, as in human speech, it is probably inappropriate to treat all calls as one type, either functionally or neurobiologically.
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The comparative neurological evidence does indicate that in humans substantial portions of neocortex on the lateral convexity of the cerebrum (like Broca's and Wernicke's areas) are critical to speech production and comprehension, whereas homologous regions in the monkey brain apparently do not play a significant role in either learned (i. e., conditioned) or spontaneous phonation (Sutton, 1979, for review; Aitken, 1981). It appears that the difference between humans and monkeys in the effects of lateral cerebral lesions on vocalization (see Jürgens et al., 1982) is due to a difference in anatomical connectivity: In humans there are direct connections between the cortical larynx area and the laryngeal motoneurones, whereas such connections are not present in the squirrel monkey (Jürgens, 1979, for review). Nevertheless, the negative results of lesions to such cerebral areas in monkeys must be interpreted cautiously. As mentioned earlier, experiments have only examined lesion effects on call frequency and acoustic structure, or conditioned responding. It may be that these measures are not sufficiently sensitive. If, for example, a primitive rule structure (or syntax) does indeed characterize monkey vocalization (see Section 2), then it is conceivable that after removal of the homolog of Broca's area (which in humans functions in the sequential aspects of speech), monkeys become unintelligible to fellow conspecifics. Here monkeys, rather than humans, must pose as aphasiologists and inform us, as for example in their response to played back calls, of more subtle abnormalities in post-lesion vocalizations. Finally, we must be cautious in drawing conclusions about human-nonhuman differences in neurological organization, as so far the essential neuroanatomical comparisons are limited to human and squirrel monkey. There is one aspect of the neural organization of human language that was once thought to be unique among primates, namely, the lateralization of function. This is clearly demonstrated in the effects of lesions on vocalization: In the majority of humans, left-sided lesions have more drastic effects on speech than right-sided lesions, whereas in monkeys only bilateral lesions (except in special cases —see below) effectively disrupt vocalization. The human left hemisphere is generally better than the right in processing and producing linguistic utterances, which appears to reflect a more fundamental hemispheric specialization for dealing with temporally
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ordered, or sequential material (Kimura, 1979; Bradshaw and Nettleton, 1981). It now appears that cerebral lateralization of function is more common among primates than previously supposed. It has been known for some years that rhesus macaques show a left hemispheric superiority for learning sequentially ordered auditory stimuli (Dewson, 1977, for review). More recently, Petersen and colleagues (Petersen et al., 1978) described a left hemispheric superiority in the discrimination of the temporal position of the peak fundamental frequency in Japanese macaque coo calls. As mentioned earlier (Section 2), this dimension of the call is the communicatively relevant one, and only the Japanese macaques among the species tested showed the lateralization effect. Furthermore, a recent lesion experiment indicates that this discrimination ability depends critically on the structural integrity of the left but not right superior temporal (including auditory) cortex (Heffner and Heffner, 1984). These studies provide the first evidence that a nonhuman primate uses lateralized cerebral mechanisms to decode its own calls. It is not clear, however, whether as in humans this type of hemispheric specialization in the auditory modality reflects a more general specialization for processing temporally ordered information or whether it is peculiar to the analysis of conspecific calls. In humans, for example, a variety of visual learning tasks can be shown to preferentially engage either left or right hemisphere mechanisms (Bradshaw and Nettleton, 1981), while in monkeys such tasks are apparently performed equally well by either hemisphere (e. g., see Hamilton, 1977, for review), suggesting that hemispheric specialization is limited to the analysis of conspecific vocalization. However, recent results, though far from conclusive, argue otherwise. Pohl (1983) tested four baboons (Papio cynocephalus) for right-left ear advantages (as an indirect measure of hemispheric dominance) in the monaural discrimination of pure tones, three-tone musical chords, synthetically constructed consonant-vowels, and vowels. These particular stimuli were selected because in humans they appear to be processed preferentially by one or the other hemisphere. All four baboons showed reproducible ear advantages on each of the four tasks. However, two of the four showed a consistent left ear (or presumed right hemisphere) advantage for all four stimuli, while in the other two animals ear advantage varied between classes of acoustic stimuli. In addition, in the latter two subjects, the ear
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opposite the one dominant for vowel discrimination showed an advantage for consonant-vowel discrimination, a finding analogous to what has been reported in humans. As there is no reason to suppose that baboons should have evolved lateralized mechanisms to discriminate human speech sounds, we must assume that their presence indicates that some fundamental auditory processing strategy common to both human speech and baboon vocalization is being employed. As stated earlier, in humans this hemispheric division of labor for speech also extends to information processing in other sensory modalities. There is a suggestion that something analogous to this may also be found in monkeys. In an experiment involving the discrimination of conspecific faces by split-brain rhesus monkeys (Hamilton and Vermeire, 1983), hemispheric specialization was found in a subgroup of subjects. In all, eighteen monkeys were tested and overall there was no significant advantage in learning the discrimination with either hemisphere; however, the nine female subjects performed better with the left than the right hemisphere. (Humans generally show a strong right hemispheric advantage on conspecific facial discrimination tasks, see below). As there was a tendency for older subjects to show greater hemispheric specialization, and the females as a group were older than the males, the experimenters suggest that the difference in results between the sexes is more likely due to the difference in age than sex per se. Thus, in rhesus monkeys this type of lateralized function may be maturation dependent. This may then explain the negative results obtained in an earlier study (Overman and Doty, 1982) that compared adult humans and immature macaques (Macaca nemestrina) on a facial discrimination task: Human subjects evidenced a strong right hemispheric superiority for analysis of human but not monkey faces, while the monkeys showed no laterality for analysis of either monkey or human faces. These studies clearly suggest that lateralization of function is much more common amongst primates (and in other mammals, Denenberg, 1981, for review and discussion) than was previously thought, but some important differences remain between humans and other primates in the nature of this neurological specialization. Particularly striking is the fact that in humans the directionality of lateralized functions (i. e., to the right or left hemisphere) is rather stable for large populations, and furthermore, it is predictably linked
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to manual preference. This implies that handedness and hemispheric lateralization are strongly linked, canalized biological processes (Corballis and Morgan, 1978; Levy, 1977), which apparently is not the case in the nonhuman primates examined so far. While some reported instances of functional lateralization (e. g., for faces, Hamilton and Vermeire, 1983) appear to be independent of individual hand preference, in the majority of cases the direction of asymmetry is dependent on individual hand preference. For example, in a preliminary report on lateralization of speech stimuli in baboons, Pohl (1982) notes that three of four subjects showed a left ear (presumed right hemisphere) advantage in accuracy of vowel discrimination, while the fourth subject, a "left hander", exhibited right ear dominance on this task. [Unfortunately, no further mention is made of hand preference in that report nor in the more detailed account of the experiment (Pohl, 1983) discussed earlier.] When the hand preferred in working a visual sequential problem (of the type that in humans preferentially engages the left hemisphere) is taken into account, rhesus monkeys learn the task faster with the hemisphere contralateral to whichever hand is preferred by the individual (Hamilton and Vermeire, 1982). This means that, unlike in humans, monkey hand preference is not fixed in the population but varies with the individual and the task performed (see also Warren, 1977) and furthermore both hemispheres are equally capable of assuming a dominant role in the learning task. Some recent lesion studies further support this interpretation. Surgical removal of somatosensory cortex contralateral but not ipsilateral to the preoperatively preferred hand produces a significant postoperative impairment in tactile discrimination by either hand (Garcha et al., 1982), indicating the existence of a kind of individually specific hemispheric "predominance" (the experimenters' term) for bilateral somatosensory representation. Similarly, hand preferences can be induced by training and then systematically altered by contralateral association cortical removal, suggesting that such functional cerebral asymmetries are acquired in monkeys (Deuel and Dunlop, 1980). Finally, Sutton et al. (19816) recently found a relationship between hand preference on a conditioned lever press task and the hemisphere governing conditioned call production in rhesus monkeys: unilateral damage to the anterior cingulate gyrus impaired conditioned vocal performance only if the
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side contralateral to the preferred hand for lever pressing was ablated. Thus, some monkey species (and perhaps language-trained apes as well, see Muncer, 1982), utilize lateralized hemispheric mechanisms for information processing and storage in auditory, visual, and somatosensory modalities, as well as in vocal motor control. In many instances, which hemisphere is dominant is determined by which hand is preferred in the required response. A much clearer idea could be had of the robustness of the association between hand preference and hemispheric dominance for various tasks if the hand preferred in responding on the tasks were routinely reported. Nonetheless, the available data indicate that a major difference between hemispheric dominance in nonhuman and human primates appears to be in the degree of plasticity of the system. In nonhuman primates handedness and cerebral dominance appear to be linked, but, in contrast to humans, both are highly plastic in that learning experience determines which hand and linked hemisphere become specialized for certain functions.
4. Implications for language origin theories I now want to examine briefly the implications of these comparative behavioral and neurobiological data for speculations about the evolutionary origin of human language. I say "speculations" because we have at the moment no direct way of determining what manner of language capacity a given fossil had. I use the common distinction between language and speech, in which the latter in modern humans is the normal manifestation (though not the only one—e. g., sign language of the deaf) of the former in the vocal-auditory channel. Substantial inroads have been made in correlating skeletal features with speech capacity in extant populations (e. g., Lieberman et al., 1972), or in identifying characteristic cranial and cerebral asymmetries (e. g., LeMay et al., 1982). The application of such techniques to fossil populations (e. g., Laitman et al., 1979) has allowed us to track evolutionary changes in cranial or cerebral organization and in upper respiratory structures related to speech production. As speech is one of the defining features of modern humans, these studies have contributed importantly to problems of both speech
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evolution (e. g., Falk, 1980) and hominid phylogeny (e. g., Laitman et al., 1979; Falk, 1983). The approach taken here is a comparative one, in which behavioral and neurological data from living primates are employed as part of a "triangulation" procedure to estimate behavioral or neurological features of early hominids. In many ways this is no more than a "best guess" procedure, but there is nevertheless a guiding logic. A key assumption is that traits shared by living humans and closely related primate species are likely to have evolved in the last common ancestor species and were subsequently also present (or retained) in the descendants comprising the lineages leading to the extant species under comparison. When very few species are involved in the comparison (e. g., African apes and humans), there is a greater probability that any shared features were evolved independently and therefore may not have been present in a particular fossil ancestor. This is one reason why Old World monkeys are of great importance in this triangulation process. Though they are less closely related to humans than are apes (and therefore less likely to share traits with humans), they are abundant in number and diverse in ecological adaptation. As a consequence, any traits shared by humans and Old World monkeys are good candidates for homology. Behaviors are judged to be homologous, however, only if they are regulated by the same (neuro)anatomical structures and mechanisms (Hodos, 1976). Much of this type of information is presently available only for monkeys. It appears unlikely that with regard to the neural mechanisms of communicative behavior any substantial progress will be made with the great apes, as many of the relevant experiments (e. g., lesion and stimulation studies) would involve invasive measures with eventual sacrifice of the subject. There are nonetheless certain noninvasive, innocuous techniques (e. g., scalp EEG), that if applied, for example, to language-trained apes, could help determine whether complex cognitive abilities displayed by apes (e. g., Ristau and Robbins, 1982; Premack, 1983, for review and discussion) are homologous to those in humans. Such knowledge would in turn provide a more realistic idea of the cognitive processes requisite to language found in early hominids. Despite the absence of significant neurobiological data from apes, it can be argued that the available information can provide some tentative idea of "baseline" communicative capacities of early
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hominids (Steklis and Raleigh, 197%). The data reviewed in this paper suggest that if the earliest hominids were derived from creatures with at least monkey-like communicative capacities, then their vocal-auditory machinery was probably far more ready to take on "primordial" speech functions than was previously supposed. In particular, the repertoire of such primordial speech may have been "open" (cf. Hockett, 1960), rather than closed (or genetically determined) as is commonly proposed for nonhuman primates. Admittedly, the evidence is meager for openness (e. g., vocal learning, vocal traditions) in the natural communication system of nonhuman primates (Section 2). It is not uncommon, however, to assume that the repertoire is closed because calls and gestures inform primarily about affective states. As mentioned earlier (Section 1), emotion-tied calls are frequently viewed as involuntary expressions (e. g., Parker and Gibson, 1979) and hence not suitable candidates for innovation nor for conveying symbolic information. This view is neither predicated on compelling logic nor is it consonant with our present knowledge of behavior (Section 2). In keeping with the views advocated in this paper, Marler (1977) has argued that symbolic and affective signals are best regarded as differing in degree rather than kind and that primates are capable of divorcing communicative behavior from affective states, with some naturally occurring elements well-suited for communicating symbolic information. If early hominids did indeed have a vocal system with at least rudimentary open qualities and ability to encode semantic information, then certain previous proposals about the origin of language may be appropriate. For example, Hockett and Ascher's (1964) proposal that a fully open speech system may have originated through a process of vocal blending, involving sounds essentially similar to those made by extant monkeys or apes, can no longer simply be dismissed on the basis that the requisite volitional abilities had not yet evolved (see Reynolds, 1968). Furthermore, "gestural" models of language origin (e. g., Hewes, 1973; Steklis and Harnad, 1976) now appear less compatible than "vocalist" models with the present comparative data on primate communicative abilities. The view advanced here, i. e., that the evolutionary history of human speech is a long one, with its beginnings in the earliest ancestral hominids, is consistent with similar conclusions derived from comparative studies of cerebral sulcal patterns in extant and fossil primates (e. g., Falk, 1980). While the cortical sulcal patterns
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(especially in the frontal-orbital region) of early (2.5 — 3.0 m. y.) South African australopithecines appear essentially ape-like, those of later (around 2.0 m. y.) hominids assigned to Homo are humanlike (Falk, 1983). Nothing is known about the external cerebral anatomy of hominids ancestral to Homo, if we assume (as many anthropologists now do) that the South African australopithecines were not ancestral to Homo. It should be noted, however, that while a human-like sulcal pattern in early forms of Homo is consistent with an early origin of human speech, the presence of this pattern does not provide direct evidence for speech nor does its absence constitute evidence against speech. In part this is because in extant human brains cortical regions important in speech (like Broca's and Wernicke's areas) are defined functionally rather than by distinctive anatomical landmarks (e. g., gyri), and they exhibit substantial individual variability in their exact location (Ojemann, 1983). Furthermore, even if we ignore these problems and assume that discrete "speech areas" could be identified on fossil endocasts, the absence of these areas would indicate no more than that the pattern distinctive of later hominids had not yet evolved. Thus "primordial" speech (as discussed earlier) may well have been based in a neural organizational plan similar to that found in extant nonhuman primates. Additional comparative neuroanatomical and physiological study of the neural organization of vocalization in primates, particularly apes, is needed to tell us where we might profitably look in fossil brains. References Aitken, P. G. 1981 Cortical control of conditioned and spontaneous vocal behavior in rhesus monkeys. Brain and Language 13. 171 — 184. Allman, J. 1977 Evolution of the visual system in the early primates. Progress in Psychobiology and Physiological Psychology 7. 1 — 53. Bauer, H. R. 1978 Chimpanzee communication and social organization: Sex differences. Paper presented at the Second Annual Meeting of the American Society of Primatologists, Atlanta, GA. Bradshaw, J. L. and N. C. Nettleton 1981 The nature of hemispheric specialization in man. The Behavioral and Brain Sciences 4 (1). 51 - 9 1 . Byrne, R. W. 1982 Primate vocalizations: Structural and functional approaches to understanding. Behaviour 80. 241-258.
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Cheney, D. L. and R. M. Seyfarth 1980 Vocal recognition in free-ranging vervet monkeys. Animal Behavior 28. 362-367. 1982 How vervet monkeys perceive their grunts: field playback experiments. Animal Behavior 30. 739-751. Cleveland, J. and C. T. Snowdon 1982 The complex vocal repertoire of the adult cotton-top tamarin, Saguinus oedipus oedipus. Zeitschrift för Tierpsychologie 58. 231—270. Corballis, Μ. C. and Μ. J. Morgan 1978 On the biological basis of human laterality: I. Evidence for a maturational left-right gradient. The Behavioral and Brain Sciences 1 (2). 261-269. Denenberg, V. H. 1981 Hemispheric laterality in animals and the effects of early experience. The Behavioral and Brain Sciences 4 (1). 1—50. Deuel, R. K. and N. L. Dunlop 1980 Hand preferences in the rhesus monkey. Archives of Neurology 37. 217-221. Dewson, J. H. 1977 Preliminary evidence of hemispheric asymmetry of auditory function in monkeys. In S. Harnad, R. W. Doty, L. Goldstein, J. Jaynes and G. Krauthamer (eds.), Lateralization in the Nervous System, 63 — 71. New York: Academic Press. Dittus, W. P. J. 1984 Toque macaque food calls: semantic communication concerning food distribution in the environment. Animal Behaviour 32. 470—477. Falk, D. 1980 Language, handedness, and primate brains: Did the australopithecines sign? American Anthropologist 82. 72 — 78. 1983 Cerebral cortices of East African early hominids. Science 221. 1072-1074. Garcha, H. S., G. Ettlinger and J. J. Maccabe 1982 Unilateral removal of the second somatosensory projection cortex in the monkey: Evidence for cerebral predominance? Brain 105. 787-810. Gouzoules, S., H. Gouzoules and P. Marler 1984 Rhesus monkey (Macaca mulatto) screams: representational signalling in the recruitment of agonistic aid. Animal Behaviour 32. 182—193. Green, S. 1975 Variation of vocal pattern with social situation in the Japanese monkey (.Macaca fuscata): A field study. In L. A. Rosenblum (ed.), Primate Behavior: Developments in Field and Laboratory Research, Vol 4. 1 — 102. New York: Academic Press. Hamilton, C. R. 1977 Investigations of perceptual and mnemonic lateralization in monkeys. In S. Harnad, R. W. Doty, L. Goldstein, J. Jaynes and G. Krauthamer (eds.), Lateralization in the Nervous System, 45—62. New York: Academic Press.
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Hamilton, C. R. and B. A. Vermeire 1982 Hemispheric differences in split-brain monkeys learning sequential comparisons. Neuropsychologia 20. 691—698. 1983 Discrimination of monkey faces by split-brain monkeys. Behavioural Brain Research 9. 263 — 275. Hansen, E. W. 1976 Selective responding by recently separated juvenile rhesus monkeys to the calls of their mothers. Developmental Psychobiology 9. 83 — 88. Heffner, Η. E. and R. S. Heffner 1984 Temporal lobe lesions and perception of species-specific vocalizations by macaques. Science 226. 75 — 76. Hewes, G. W. 1973 Primate communication and the gestural origin of language. Current Anthropology 14, 5—24. Hockett, C. F. 1960 Logical considerations in the study of animal communication. In W. E. Lanyon and W. N. Tavolga (eds.), Animal Sounds and Communication, pp. 292 - 340. A. I. B. S., No. 7, Washington, D. C. Hockett, C. F. and R. Ascher 1964 The human revolution. Current Anthropology 5. 135 — 168. Hodos, W. 1976. The concept of homology and the evolution of behavior. In R. B. Masterton, W. Hodos and H. Jerison (eds.), Evolution, Brain, and Behavior: Persistent Problems, 153 — 168. New York: John Wiley and Sons. Humphrey, Ν. K. 1976 The social function of intellect. In P. P. G. Bateson and R. A. Hinde (eds.), Growing Points in Ethology, 303 — 317. Boston: Cambridge University Press. Jürgens, U. 1979 Neural control of vocalization in non-human primates. In H. D. Steklis and M. J. Raleigh (eds.), Neurobiology of Social Communication in Primates: An Evolutionary Perspective, 11 —44. New York: Academic Press. Jürgens, U., A. Kirzinger and D. Cramon 1982 The effects of deep-reaching lesions in the cortical face area on Phonation: a combined case report and experimental monkey study. Cortex 18. 125-140. Kaplan, J. N., A. Winship-Ball and L. Sim 1978 Maternal discrimination of infant vocalizations in squirrel monkeys. Primates 19. 187-194. Kimura, D. 1979 Neuromotor mechanisms in the evolution of human communication. In H. D. Steklis and M. J. Raleigh, (eds.), Neurobiology of Social Communication in Primates: An Evolutionary Perspective, 197 — 220. Kirzinger, A. and U. Jürgens 1982 Cortical lesion effects and vocalization in the squirrel monkey. Brain Research 233. 299-315.
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Laitman, J. T., R. C. Heimbuch and E. S. Crelin 1979 The basicranium of fossil hominids as an indicator of their upper respiratory systems. American Journal of Physical Anthropology 51. 15-34. Lancaster, J. B. 1968 Primate communication systems and the emergence of human language. In P. C. Jay (ed.), Primates: Studies in Adaptation and Variability, 439-457. New York: Holt, Rinehart and Winston. LeMay, Μ., M. S. Billig and N. Geschwind 1982 Asymmetries of the brains and skulls of non-human primates. In E. Armstrong and D. Falk (eds.), Primate Brain Evolution: Methods and Concepts, 263 — 277. New York: Plenum. Levy, J. 1977 The origins of lateral asymmetry. In S. Harnad, R. W. Doty, L. Goldstein, J. Jaynes and G. Krauthamer (eds.), Lateralization in the Nervous System. 195 — 209. New York: Academic Press. Lieberman, P., E. S. Crelin and A. H. Klatt 1972 Phonetic ability and related anatomy of the newborn and adult human, Neanderthal man, and the chimpanzee. American Anthropologist 74. 287-307. Marler, P. 1973 A comparison of vocalization of red-tailed and blue monkeys, Cercopithecus ascanius and C. mitis, in Uganda. Zeitschrift für Tierpsychologie 33. 223-247. 1977 Primate vocalization: Affective or symbolic? In G. H. Bourne (ed.), Progress in Ape research. 85 — 96. New York: Academic Press. Marler, P. and L. Hobbett 1975 Individuality in a long-range vocalization of wild chimpanzees. Zeitschrift fur Tierpsychologie 38. 97 — 109. Masataka, N. 1982 A field study on the vocalizations of Goeldi's monkeys (Callimico goeldii). Primates 23. 206-219. 1983a Psycholinguistic analysis of alarm calls of Japanese monkeys (Macaca fuscata fuscata). American Journal of Primatology 5. 111 — 125. 19836 Categorical responses to natural and synthesized alarm calls in Goeldi's monkeys (Callimico goeldii). Primates 24. 40 — 51. Muncer, S. J. 1982 Functional asymmetry in the chimpanzee. Perceptual and Motor Skills 54. 147-152. Myers, R. 1976 Comparative neurology of vocalization and speech: Proof of a dichotomy. In S. R. Harnad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech, Annals of the New York Academy of Sciences 280. 745—757. Newman, J. D. and P. D. MacLean 1982 Effects of tegmental lesions on the isolation call of squirrel monkeys. Brain Research 232. 317-329.
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Newman, J. D. and D. Symmes 1982 Inheritance and experience in the acquisition of primate acoustic behavior. In C. T. Snowdon, C. H. Brown and M. R. Petersen (eds.), Primate Communication 259 — 278. Boston: Cambridge University Press. Ojemann, G. A. 1983 Brain organization for language from the perspective of electrical stimulation mapping. The Behavioral and Brain Sciences 6 (2). 189 — 230. Orgogozo, J. M. and B. Larsen 1979 Activation of the supplementary motor area during voluntary movement suggests it works as a supramotor area. Science 206. 847—850. Overman, W. H. and R. W. Doty 1982 Hemispheric specialization displayed by man but not macaques for analysis of faces. Neuropsyschologia 20. 113 — 128. Parker, S. T. and K. R. Gibson 1979 A developmental model of the evolution of language and intelligence in early hominids. The Behavioral and Brain Sciences 2. 367 — 381. Pereira, M. and H. Bauer 1978 Individual recognition of juvenile offspring by Japanese macaque mothers of "coo" vocalizations. Paper presented at the Second Annual Meeting of the American Society of Primatologists, Atlanta, Ga. Petersen, M. R. 1982 The perception of species-specific vocalizations by primates: A conceptual framework. In C. T. Snowdon, C. H. Brown and M. R. Petersen (eds.), Primate Communication, 171—211. Boston: Cambridge University Press. Petersen, M. R., M. D. Beecher, S. R. Zoloth, D. B. Moody and W. C. Stebbins 1978 Neural lateralization of species-specific vocalizations by Japanese macaques (Macaca fuscata). Science 202. 324—327. Plooij, F. X. 1978 Some basic traits of language in wild chimpanzees. In A. Lock (ed.), Action, Gesture and Symbol. 111 — 133. New York: Academic Press. Pohl, P. 1982 Hemispheric lateralization of speech perception in the baboon. International Journal of Primatology 3. 323. 1983 Central auditory processing V. Ear advantages for acoustic stimuli in baboons. Brain and Language 20. 44 — 53. Premack, D. 1983 The codes of man and beast. The Behavioral and Brain Sciences 6 (1). 125-167. Reynolds, P. C. 1968 Evolution of primate vocal-auditory communication systems. American Anthropologist 70. 300-308. Ristau, C. A. and D. Robbins 1982 Language in the great apes: A critical review. In J. S. Rosenblatt, R. A. Hinde, C. Beer and M. C. Busnel (eds.), Advances in the Study of Behavior, Vol. 12. 141—255. New York: Academic Press. Robinson, J. G. 1979 Organization of vocal communication in the titi monkey. Zeitschrift für Tierpsychologie 49. 381-405.
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Rowell, Τ. E. and R. A. Hinde 1962 Vocal communications of the rhesus monkey (Macaca mulatto). Proceedings of the Zoological Society of London 138. 279 — 294. Seyfarth, R. M. and D. L. Cheney 1980 The ontogeny of vervet monkey alarm calling behavior: A preliminary report. Zeitschrift für Tierpsychologie 54. 37 — 56. 1982 How monkeys see the world: A review of recent research on East African vervet monkeys. In C. T. Snowdon, C. H. Brown and M. R. Petersen (eds.), Primate Communication, 239 — 252. Boston: Cambridge University Press. Seyfarth, R. M., D. L. Cheney and P. Marler 1980 Vervet monkey alarm calls: Semantic communication in a free-ranging primate. Animal Behavior 28. 1070-1094. Snowdon, C. T. 1982 Linguistic and psycholinguistic approaches to primate communication. In C. T. Snowdon, C. H. Brown and M. R. Petersen (eds.), Primate Communication, 213 — 237. Boston: Cambridge University Press. Snowdon, C. T., C. H. Brown and M. R. Petersen (eds.) 1982 Primate Communication. Boston: Cambridge University Press. Snowdon, C. T. and J. Cleveland 1980 Individual recognition of contact calls by pygmy marmosets. Animal Behavior 28. 717-727. Snowdon, C. T. and Υ. V. Pola 1978 Interspecific and intraspecific responses to synthesized pygmy marmoset vocalizations. Animal Behavior 26. 192—206. Steklis, H. D. and S. R. Hamad 1976 From hand to mouth: Some critical stages in the evolution of language. In S. R. Harnad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech, Annals of the New York Academy of Sciences 280. 445-454. Steklis, H. D. and M. J. Raleigh (eds.) 1979a Neurobiology of Social Communication in Primates: An Evolutionary Perspective. New York: Academic Press. Steklis, H. D. and M. J. Raleigh 19796 Requisites for language: Interspecific and evolutionary aspects. In H. D. Steklis and M. J. Raleigh (eds.), Neurobiology of Social Communication in Primates: An Evolutionary Perspective. 283 — 314. New York: Academic Press. Struhsaker, Τ. T. 1967 Auditory communication among vervet monkeys (Cercopithecus aethiops). In S. A. Altmann (ed.), Social Communication Among Primates, 281—324. Chicago: University of Chicago Pres*. Sutton, D. 1979 Mechanisms underlying vocal control in non-human primates. In H. D. Steklis and M. J. Raleigh (eds.), Neurobiology of Social Communication in Primates: An Evolutionary Perspective. 45—68. New York: Academic Press.
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Sutton, D., R. E. Trachy and R. C. Lindeman 1981a Vocal and nonvocal discriminative performance in monkeys. Brain and Language 14. 93 — 105. 19816 Primate phonation: Unilateral and bilateral lesion effects. Behavioural Brain Research 3. 99-114. Trachy, R. E., D. Sutton and R. C. Lindeman 1981 Primate phonation: Anterior cingulate lesion effects on response rate and acoustical structure. American Journal of Primatology 1. 43 — 55. Warren, J. M. 1977 Handedness and cerebral dominance in monkeys. In S. R. Hamad, R. W. Doty, L. Goldstein, J. Jaynes and G. Krauthamer (eds.), Lateralization in the Nervous System, 151 — 172. New York: Academic Press. Waser, P. M. 1977 Individual recognition, intragroup cohesion and intergroup spacing: Evidence from sound playback to forest monkeys. Behaviour 60. 28-74.
Part II Perceptual bases
Grasping and the gesture theory of language origins Joseph L. Fischer
Abstract A crucial issue in glossogenetics is whether the first steps toward the development of a productive language possessing syntactic constructions involved principally manual gestures, as many believe, or vocalizations. The thesis presented here is that the vital need of early hominids to keep a weapon constantly in hand for defense against predators greatly limited the use of manual gestures for communication. At the same time, the development of an adequate defense against predators through weapons reduced the need for remaining silent and permitted free use of vocalization for any needed function, including symbolic communication. Considerable evidence has been assembled to support the theory that early hominids first developed a fairly complex language of manual gestures, and only later transferred the consequent symbolic capacity to the vocal-auditory mode. We may mention here the experiments teaching great apes human sign language, the universal tendency to accompany spoken language with gestures, the use of gestures for communication by human infants before the first intelligible words, the increased use of gestures in language contact situations, the facility of deaf mutes in using and innovating sign language, the innate and emotional nature of the vocalizations of other primates, the late development in the fossil record of the human vocal tract. This and other evidence has been ably summarized and analyzed by Hewes (1973, 1976, 1983). It is, however, the thesis of this paper that the first terrestrial hominids urgently needed hands for other purposes, and that at the same time the vocalauditory channel became more available for communication than it had been, so that a fairly complex language probably developed first with the vocal-auditory channel.
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By 'fairly complex language' is meant here a system of communication, whether gestural or vocal, with an open, learned lexicon of several hundred signs — probably in some degree iconic — and with the ability to combine these meaningfully in small groups, not necessarily at first in any special order. The spontaneous systems of gestural communication devised by isolated deaf mutes seem to be of this order of complexity, as do the initial stages of spoken language exhibited by young children.1 Some people may object that such systems do not deserve to be called language at all, since they lack one or more crucial features of language, such as a fixed order of morphemes and lexemes, or what Martinet calls "double articulation" and Hockett "duality of patterning". This is simply a quibble about definitions which is of no great importance. We are clearly talking about something like modern language in some key features but simpler; something which is not an everyday phenomenon in the world of normal adults of any species today. Therefore it is to be expected that the full sense of the word 'language' will not apply to it in all respects. The difference in sense can be easily handled in context, adding modifiers such as 'proto-' or 'primitive' when a contrast with fully modern language is to be specified. Elsewhere I have suggested how the vocal naming of simple objects and acts of interest in the environment could be expected to develop in a terrestrial hominid, once the need for the inhibition of vocalization was reduced by the regular use of defensive weapons against large predators (Fischer, 1974, 1983). The present paper is complementary to the earlier ones in proposing further that not only did the use of weapons permit increased vocalization but it discouraged the elaboration of gestures beyond that already found in wild great apes. It is a general capacity of mammals, not just primates, to pay close attention to the movements of other individuals and to infer their probable imminent actions from fairly slight movements (gestures, by some interpretations) in preparation for more vigorous and decisive action. Thus a dog which bares its teeth is understood by another dog as having aggressive intent even before it actually bites or even if it does follow through with an actual bite. Among the great apes, movements of the hands and arms are especially important, since they are used in locomotion, feeding, grooming, and aggression, including waving branches and throwing missiles. We may thus expect that our common ancestors with the African
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great apes did pay considerable attention to what their bandmates did with their hands. We may also assume that they were able to perform many conscious and precise movements with their hands when they needed to, as chimpanzees and gorillas can today. However, if an interest in the manual movements of others and the conscious control of precise manual movemements were enough to account for the development of a fairly complex gestural protolanguage, one would expect chimpanzees and gorillas, and probably many other species of primates, to have developed such a mode of communication in the wild. Various wild primates have been reported to use their hands to manipulate accurately selected natural objects as tools equivalent to human digging sticks, hammers and anvils, towels and handkerchiefs, sponges, umbrellas, clubs, probes, picking poles, fly whisks, missiles, drums, etc. (Beck, 1975). Yet in spite of their conscious manipulation of objects, extensive observation of wild primates in recent years suggests that they have failed to develop the equivalent even of the gestural communication of the isolated human deaf. Wild primates are attentive to manual gesture, and social communication occurs through gesture, posture, and facial expression, but I have been unable to find any clear reports of wild animals using arbitrary learned gestures (symbols, in one sense of the term) or complex series of gestures to be interpreted as a group, on the order of a simple phrase or sentence. The experiments teaching human sign language to captive great apes are to me convincing that these animals have the capacity to understand tutelage to learn to make a few hundred arbitrary gestures, and to make simple sequences or groups of these gestures in order to communicate appropriately. This shows a certain basic intellectual similarity to humans. But they are slower to learn these signs than human deaf children, and the meaningful sequences which they produce seem to be shorter. The fact that the great apes can be trained and coaxed by humans to use proto-language does not mean that by themselves they would ever develop this ability. Captive chimpanzees can be taught many things, such as riding bicycles and driving automobiles, which they would be unlikely to develop in the wild, even if they spied on humans. Various explanations have been offered as to why wild great apes lack a symbolic gesture language. I would disagree with most of them. One is that they have nothing to communicate to each other which cannot be conveyed simply by action in context. On the
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contrary, there seem to be many useful things which wild apes could learn through language from their conspecifics if they only had realized the capability: e. g., the habits of leopards, hyenas, and other predators; what foods are found where in the band territory at different seasons; which snakes are poisonous and which harmless; the tendencies to antisocial behavior of certain adult males; the relationships with neighboring bands, etc. Of course, the apes still manage to survive without symbolic communication about these matters. But it would seem that symbolic communication could increase the survival potential of those practicing it. Another explanation for the lack of ape language is the sheer small size of the ape brain. This again seems questionable, as humans with pathologically small brains and children with major injuries to normal brains can often still learn to speak. If brain size were the critical variable, one might expect that the great apes would have some capacity for spontaneous language in the wild, even if less than humans. Moreover, anecdotal evidence indicates that the great apes do have the capacity for passive understanding of a surprising amount of human speech in addition to sign language. There seems to be some organizational difference between ape and human brains apart from size which affects linguistic capacity. Study of brain endocasts suggests that differences of brain conformation related to human intellectual and linguistic capacities may go back to a time when hominid brains were comparable in size to those of modern apes (Holloway and De la Coste-Lareymondie, 1982: 101; Wolpoff, 1982: 509). Because of an organically based deficiency of symbolic capacity I suggest that wild apes without special training naturally interpret the gestures of others, including consciously controlled manual movements, as imminent action toward themselves or other parts of the environment. Also, since they use their hands so much for immediate practical purposes — locomotion, defense, grooming and social contact, feeding — the hands are too busy most of the time to develop a system of learned symbolic communication. It is parsimonious to assume that similar practical restrictions on hand use applied to our common arboreal ancestors with the African great apes and to our first terrestrial ancestors. The descent of man's ancestors from the trees could only have been successfully achieved with the extensive use of weapons: clubs of wood and perhaps bone, and missiles of stone. The constant need to carry
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weapons and tools would inhibit the symbolic use of gesture. The earliest terrestrial hominids lacked manufactured tools according to evidence to date, but since various higher primates, especially chimpanzees, which are still rather arboreal, use suitable natural stones as tools and missiles, the early terrestrial hominids surely had a similar capacity and a much greater need to make use of it to defend themselves against predators. Early hominids lacked the large canines of the adult male chimpanzees, and their arms were smaller and weaker. They lacked the speed for running short distances needed to escape the large carnivores on land. They may have been able to climb trees better than modern man, but not as well as a chimpanzee. More important, they seem to have evolved in open country where nearby trees to climb were often missing. There is still much debate about the importance and nature of hunting by early hominids such as the australopithecines.2 I believe that hunting and meat-eating were quite important, since the same weapons needed for defense against predators could be used effectively in hunting game for food. Moreover, regular practice with weapons in hunting would help improve the use of the same weapons for defense against predators. But even if simple weapons were used little for hunting, it is clear that they would have been essential for defense from predators. Our ancestors would have had to have them constantly available. De Grolier has called my attention to the important recent book by Brain (1981) on the origin of Pleistocene bone deposits in African caves. Brain presents a convincing case to show that the bone deposits in the earlier caves, including australopithecine bones, were the remains of prey brought there by leopards and other large predators. Brain (1981: 34) considers that "the staple diet of African huntergatherers has probably always been vegetable," although he adds that "meat has represented a much sough-after, but often unessential, bonus" (Brain, 1981:34). The evidence in Brain's book might be taken by some to imply that hunting and armed defense against predators were unimportant in early hominids. The book's title — The Hunters or the Hunted? — with its answer that large predators successfully preyed on early hominids and other primates — implies that early hominids were not hunters, but rather the prey of carnivores. However, of course, they could well have been both. While Brain (1981) concludes that hominids were the prey of leopards and other carnivores, he also recognizes that "Hominids
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and baboons must be regarded as dangerous prey for any predator — not because the individual primate is a formidable adversary, but simply because an attack on one individual is likely to precipitate retaliation by the whole band..." (Brain, 1981: 270). I would agree that both hominids and baboons present a danger to predators, but this remark glosses over some important differences between baboons and hominids. A single alert adult male baboon could be a fairly formidable adversary to a leopard. Even if the baboon failed to kill the leopard it might injure it seriously with its large canine teeth. But a leopard would be likely to prevail over a group of several unarmed hominids and it would be hard for them to inflict serious injury on the leopard with bare hands and feet. Perhaps the best hope for an unarmed hominid would be to leap on the leopard's back and blind it with thumbs in both eyes, but the chances of achieving this with an alerted animal would seem small. However, a single adult australopithecine, male or female, armed with a stout club, would be a formidable adversary to a leopard or any carnivore. It would be hard for the hominid to kill a large alerted carnivore with only a club, but he or she could wound it seriously, bruising the forelimbs or breaking the teeth or facial bones if it persisted in an attack. And weapons which might not kill a large carnivore could be effective in taking smaller game. Brain's conclusion that some of the early hominid remains were dragged to caves by large carnivores highlights the absolute necessity of a reasonably effective defense against these predators. The only effective defense which I can think of would be some form of weapon. Of course a "reasonably effective defense" might let the carnivores win some of the time by stealthy attacks on lone hominids. Even today, from time to time we read of bears killing people in Yellowstone Park. Brain himself cites cases of man-eating leopards in India in recent times which killed many humans, as many as four hundred victims for one male leopard (Brain, 1981: 98). Recent cases of man-eating lions and tigers could also be cited. But all that is necessary to ensure the survival of the species is that on the average each adult growing to maturity produces two children who in turn grow to maturity, however many others are eaten by leopards, sabertoothed tigers, and the like. In recent times in most parts of the world, predators have not been a serious problem for humans. Modern lovers of wildlife defend such animals as wolves, lions, bears, tigers, and pumas as noble and lovable
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creatures which, even when hungry, usually spare humans, even when these are unarmed and alone, although tropical forest predators such as leopards and jaguars seem to have fewer partisans. We are surely flattering ourselves, however, if we believe that these large and powerful predators spare us because they recognize the rightful place of Homo sapiens sapiens at the head of the great chain of terrestrial beings, a little lower than the angels but ahead of the king of beasts. They spare us rather because their ancestors have learned over many millennia that hominids are very dangerous and vengeful. In open country and even in temperate forests, determined bands of human hunters, armed with simple weapons, can track down and kill or seriously wound even large predators, although in dense tropical jungles this becomes more difficult. But when the first hominids began terrestrial life, the defense against predators must have been less efficient. Wild chimpanzees make what could be called very crude clubs, but are not reported to make spears or lances. Something similar to chimpanzee clubs, perhaps more stripped of excess twigs and leaves, must have been the principal weapon of early hominids. Wild chimpanzees at times also use stones effectively as missiles, and it is fair to assume that early hominids shared this capability. However, a supply of suitable stones is not always naturally at hand, and would be hard to carry around and keep available. The stones needed to discourage large predators would have to be fairly large and heavy. These would not only be hard to carry far but also hard to throw effectively at great distances. To be sure, early hominids might have had stockpiles of stone missiles by their camps to chase away prowling predators. But the predator could safely come much closer to early hominids than to those who later developed more effective projectiles: slingstones, spears, and arrows to keep these bolder early predators at bay while hunting and gathering away from the home camp, early hominids would have needed to carry a club or a very stout pole at all times. They would most likely carry this weapon in their dominant hand, which would inhibit its use in gesture. Holding on to a wooden weapon probably gave early hominids a sense of security. It is a kind of natural persistent behavior in arboreal primates to hold on to branches while at rest as well as in locomotion. This same preference for grasping could have been retained and transferred to portable clubs, poles, rocks, and other objects when our ancestors became primarily terrestrial.
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Even today modern man seems to find a pleasure in grasping and holding things which in some cases have no practical function. Seated in an armchair, we are likely to grasp the arm. Standing, we may put our hands in our pockets in such a way as to grasp the edge, or fold our arms so that one hand grasps the other arm just above the elbow. Very small children will pick up small objects and carry them around without paying any attention to them. Informal observations carried out in New Orleans by a graduate student, Debra Hart-Bittman, and myself, suggest that people in public places are often carrying or holding things or grasping objects in the environment, that their grasping fairly often appears to have no practical value, and that when they are grasping things, their use of gesture tends to be reduced. While people often gesture during conversation, the inhibition of gesture due to grasping objects nearby has little effect on the adequacy of communication. In conversation people generally look others in the face and observe gestures through peripheral vision. Television and movie cameras generally concentrate on the faces of parties engaged in extended conversation. The actors or speakers may often be gesturing, but their gestures are treated as irrelevant, redundant, or less important than facial expression. The development of the use of weapons and the carrying of other objects such as food and other supplies back to a home base could be expected to increase the importance of vocal communication by inhibiting gestures. With an adequate defense against predators thanks to weapons in the hands of adults, the reason for inhibiting vocalization of the young would vanish. As numerous observers have noted, infant chimpanzees have a period of vocalization which has been compared to human babbling, but this does not continue to develop into more complex vocalization. This early vocalization probably helps strengthen the mother-infant bond in both species and also helps the mother monitor the needs of the infant (Jonas and Jonas, 1975). Kortlandt has pointed out (1973: 12) that chimpanzee 'babbling' continues as long as the infant remains clinging to its mother, but that as it begins to venture away from her at times the child becomes silent. Vocalization at this stage would be likely to attract the attention and attack of predators. As chimpanzees mature, the adults, especially the males, become vocal again, particularly when in groups. At this point they are able to defend themselves and other members of the band against leopards, so vocalization has the
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function, among others, of frightening off rather than attracting predators. But as Kortlandt (1973) further notes, human children make a lot of noise talking and shouting, even though engaged in play activities which are otherwise very similar to those of silent chimpanzees of the same developmental age. The noise of the human children also enables the mothers to keep track of them when out of sight nearby. The mothers can retrieve them if they wander too far, and can run to their protection and assistance if need be. The idea has previously been popular that somehow tool use was associated with the development of language. It used to be claimed that any animals would need instructions through language in order to make and use tools. This idea still has some momentum, but has been much criticized since the accumulation of records of the use of simple tools and weapons by wild great apes, which appear to learn these by observation and imitation. Indeed, observation and imitation seem also to be the principal ways in which modern humans learn to make and use tools. Deaf mutes learn such things about as well as people with normal speech and hearing. Spoken instruction on manual operations are often largely deictic and redundant, e. g., 'Watch me closely... This is the way to do it...' Written instructions are often accompanied by a series of pictures, which may convey the information more rapidly and surely than the text. Certainly language is very important in human life, but there are other ways of conveying information. Our desire to distinguish ourselves from apes is no reason to exaggerate the importance of language. Hewes (1973: 8—9) has proposed that the greater amount of dexterity developed by the use of tools was a precondition for the development of complex gestures and that this was followed by the development of a gestural proto-language. While modern man appears to have somewhat greater manual dexterity than the great apes, my position here is that the great importance of the hands for early hominids for keeping weapons readily available and for some other purposes was on the contrary a reason why the hands were used rather little for gestures, perhaps less than in modern Homo sapiens. Moreover, great apes need remarkably good handeye coordination to swing through the trees and snatch an alternative branch or vine if they miss their first target. Social grooming also involves delicate hand-eye coordination of a different sort. The fact that captive chimpanzees, gorillas, and orang-utans have all been successfully taught a number of arbitrary gestures of the
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American Sign Language for the deaf and can learn complicated visual-motor tasks, implies that our remote ancestors would have had the necessary muscular control for a gesture language even before their descent from the trees. However, like the modern pongids, they probably did not use the control for this purpose. Another fact cited by Hewes and others as evidence of the relation between gesture and language is the finding that usually the cerebral hemisphere controlling speech also controls handedness (the left hemisphere in right-handed persons). This calls for an explanation, but it may perhaps be explained simply by the fact that tool use by the dominant hand and speech both involve fairly long organized sequences, and that linear or sequential behavior seems to be more under the control of the dominant hemisphere. Linear thinking is probably more developed in humans than in other primates, but is by no means restricted to linguistic communication. More generally it is an aspect of foresight and planning, which involve the consideration of long series of actions beyond the immediate context. Incidentally, this would be of greater value in hunting than in collecting vegetable food, since pursuing prey requires more preparation and persistence. In brief, the increased use of weapons and tools does appear to have been linked to the evolution of language and speech, but for reasons different from those commonly advocated. I propose instead that tools, and even more specifically weapons, were crucial in providing an adequate defense against predators for ground-dwelling early hominids, thereby removing the need for inhibiting vocalization in the young. At the same time the use of weapons and tools may have inhibited the use of the hands for social communication, tipping the balance in favor of vocal play and communication. Notes 1. Incidentally, Volterra (1981) finds that hearing infants, even though they develop intelligible single gestures before words, spontaneously produce meaningful sequences of spoken words before sequences of gestures, which in fact she did not observe at all in young children. 2. Harding (1975), reviewing meat-eating among the primates, concludes that early hominids must have been partly carnivorous since occasional meat-eating is widespread among living primates. However, he also argues from this that therefore hunting did not distinguish the human line from other primates and had little evolutionary significance. I would interpret the same evidence as permitting the possibility that early hominids not only hunted occasionally but
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hunted much more than other primates, and that this had a number of evolutionary consequences, including increased weapon and tool use, more tightly organized bands, the use of fire, and eventually full vocal language.
References Beck, Benjamin B. 1975 Primate tool behavior. In R. H. Tuttle (ed.), Socioecology and Psychology of Primates. 413—447. The Hague: Mouton. Brain, C. K. 1981 The Hunters or the Hunted? Chicago: The University of Chicago Press. Fischer, J. L. 1974 Vocal magic, imitative speech and the syntax of behavior. In R. W. Wescott (ed.), Language Origins. 207 — 212. Silver Spring, Maryland: Linstok. 1983 Magical imitation in the origin of language. In E. de Grolier (ed.), Glossogenetics. The Origin and Evolution of Language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 313 — 328. Chur, Switzerland: Harwood Academic Publishers. Harding, R. S. O. 1975 Meat-eating and hunting in baboons. In R. Tuttle (ed.), Socioecology and Psychology of Primates. 245 — 257. The Hague: Mouton. Hewes, Gordon W. 1973 Primate communication and the gestural origin of language. Current Anthropology 14. 5 — 24. 1976 The current status of the gestural theory of language origin. In S. Harnad, S. R. Harnad, H. D. Steklis, and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 482-504. New York, N.Y.: The New York Academy of Sciences. 1986 Ways to accelerate progress in glottogonic research. This volume Pp. 79-88. Holloway, R. L., and M. C. De la Coste-Lareymondie 1982 Brain endocast asymmetry in pongids and hominids. American Journal of Physical Anthropology 58. 101 - 1 1 0 . Jonas, D. F., and A. D. Jonas 1975 Gender differences in mental function: A clue to the origin of language. Current Anthropology 16. 626 — 630. Kortlandt, A. 1973 Comment on Hewes 1973, op. cit. Current Anthropology 14. 13 — 14. Volterra, Virginia 1981 Gestures, signs, and words at two years: When does communication become language? Sign Language Studies 33. 351—361. Wolpoff, Milford H. 1982 Ramapithecus and human origins. Current Anthropology 23. 501 — 522.
Ways to accelerate progress in glottogonic research Gordon W. Hewes
Abstract The problem of language origins received new attention starting ca. 1970. The literature continues to expand, and there have been important meetings in 1972, 1975, and 1981. In ape language studies greater diversity in language vehicles is urged. ASL (American Sign Language) is less iconic than generally supposed and systems with greater iconicity might achieve better results. More attention should be devoted to the problem of accounting for phonemes in existing spoken languages, and the condition of speech in a pre-phonemic stage. In utero learning has been demonstrated in sheep; some in utero adaption to speech may occur in human fetuses. The doctrine that all existing languages are equally efficient needs close reexamination. More work should be undertaken on the capacities of certain domestic animals to understand some aspects of human speech. The expanding use of computers should make it easier to attack several glottogonic problems.
Fifteen years have passed since the old question of the ultimate origin of language began to recover some intellectual respectability. This revival of interest was partly stimulated by the ape language experiments, but also by Hockett's (1961) analysis of the design features of language, the work of Lenneberg (1967) and others on the biological foundations of language, and the efforts of the physical anthropologists to go beyond bones and teeth to the reconstruction of early hominid environments and behavior. By 1972 a special session on language origins was held at the Toronto meeting of the American Anthropological Association. In 1975 there was a very large conference on this subject in New York, under the sponsorship of the New York Academy of Sciences. In 1981 a smaller but
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more focused symposium was held in Paris, under the egis of the International Social Science Council of UNESCO. The present volume results from the Symposium on Origins of Language at the Xlth International Congress of Anthropological and Ethnological Sciences in Vancouver, in 1983. Serious scientific contributions to glottogonic studies have appeared frequently, including, Hildebrand-Nilshon (1980), Lock (1980), Bickerton (1981), Gans (1981), and Lieberman (1984). With the numerous journal articles over the past half decade, these books, taken as a whole, provide an excellent survey of the state of the art of glottogonic speculation as of 1980 — 1985. Here, however, I shall look forward, with some suggestions which might be able to accelerate progress in this interdisciplinary field. 1. I start with the ape language experiments because it was early accounts of some of them by the Gardners (1969) and Premack (1970, 1971), which led to my own involvement with glottogenesis, although as an anthropologist I had a general curiosity about how mankind might have achieved language. I am mindful of the strong attacks on the ape language studies by Sebeok (1981), UmikerSebeok (1980), Terrace (1979), and Seidenberg (1984), and the dismissal of their relevance by Chomsky (1968) and others, who continue to support a Cartesian view of the 'unbridgeable gulf between man and beast. Much of the criticism by Sebeok (1981) related to the supposed Clever Hans cueing effect, although even the experimenters using ASL as the language vehicle for their experiments with apes were well aware of such pitfalls, and the computer-mediated experiments of Rumbaugh (1977), and others, precluded such cueing. My recommendations for future ape-language research are not directed toward the Clever Hans effect, but rather to some alternatives with respect to the kinds of language used in the experiments hitherto. In all of the reported ape studies, the languages have either been only partly iconic, or deliberately without iconicity. ASL is much less visually iconic than those unfamiliar with it might suppose. Only a small percentage of the manual gestures which make up its lexicon are so obvious in meaning as to be immediately understood by normal human beings worldwide. Many are 'iconic' only when one has been told how the sign originated. Thus, the sign for 'woman' is a gesture derived in the late eighteenth or early
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nineteenth century from a lady's bonnet-strap, hardly a gesture of pan-human significance. It is not at all easy for a hearing person to learn ASL, given, among other difficulties, the low frequency of obviously iconic signs. Apes presumably find it even harder to learn. Premack (1970, 1971) used word-signs consisting of small plastic cut-outs of deliberately arbitrary shapes and colors; the lexemes of Yerkish, the constructed language in the LANA project, were likewise entirely abstract patterns bearing no visual reminder of their referents. These efforts stem from the acceptance of de Saussure's (1959) doctrine of the arbitrariness of the linguistic sign, although in fact existing, natural, spoken languages present a definite substratum of sound-symbolism or acoustic iconism. I should like to see some ape language experiments with codes deliberately constructed to maximize rather than to minimize iconism. It seems plausible to me that the earliest language — gestural or vocal — was probably more iconic than not; in any case, it is far easier to remember that a realistic picture of an apple stands for 'apple,' than that a gray triangle or complex diagram of straight and curved lines flashed on a screen means 'apple.' Never mind that apples may come in several colors, or that not all leaves are the same shape. Where the number of sign-units in a communication system is small (as seems likely for mankind's earliest languaages), system is small (as seems likely for mankind's earliest languages), used for traffic signs, and to label facilities in international airports. Anyone who has had to search for a public restroom in a foreign country has probably had reason to be grateful for iconic labels of this kind. Moreover, the earliest known system of writing, in several widely separated parts of the world, were pictorial; Saussurean dogmatists were not around to point out the error of this to the earliest scribes. Also, with regard to ape language experiments, I would like to see some of them carried out in quasi-naturalistic environments, rather than in modern learning laboratories, or in modern domestic settings. Thus, it has often been suggested that proto-language in the hominids arose in part in connection with hunting, an activity engaged in, to some extent, by modern wild chimpanzees. While it might require considerable ingenuity and expense, chimpanzee subjects in some language studies might be encouraged to hunt and kill smaller mammals (such as sheep) under conditions where cooperative behavior would enhance hunting effectiveness, and
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where shortages of other kinds of food might induce the subjects to kill for nourishment. There are some small islands with just the right kind of terrain and vegetation for such a study. Given the propensity (again, for chimpanzees) to make some very simple tools, conditions might be provided to combine tool-making and language-using capabilities. 2. The work of Lieberman and Crelin (1971) and, more recently, Laitman (1984), on the reconstruction of the vocal tracts of human newborns, anthropoid apes, and various fossil hominids, has been of very great importance for glottogonic theorizing. I suggest a possible terminus ad quo for the appearance of spoken language of fully modern type (i. e., no more than about 400,000 or 300,000 years ago), prior to which hominid vocal communication would have not been at all like present-day speech. But hominids before 300,000 — 400,000 years ago were already making stone implements to a pattern, and possibly using fire, as well as hunting large game. It is difficult to believe that they had no usable language by the beginning of the Homo erectus era, a million or more years ago. If they were indeed speechless (though capable of producing a full range of primate vocal calls, similar to those emitted by modern apes) they must have had some kind of gestural proto-language. Perhaps they combined some voluntary vocalizations (and clicks?) with manual and other gestures, postures, and facial expressions. On the other hand, a terminus ad quem for the appearance of fully modern-type articulate speech does not seem possibly later than about 40,000 years ago, when populations with modern faciocranial features were present very widely in the Old World, readily distinguishable from non-Homo sapiens sapiens men. In a paper of mine (Hewes, 1983α), I borrowed Krantz' (1980) well-argued hypothesis for the relation of modern craniofacial structure to the rapid pan-human diffusion of "fully phonemicized spoken language." Krantz makes good sense for this transformation as the outcome not of worldwide gene-flow, but of repeated and rapid natural-selective adjustment to a new form of language, dependent on phonemes and capable of extremely rapid production and decoding. Krantz did not elaborate on his notion of "phonemicized speech," but I did in the 1983a paper referred to. I argued that the initial value of phonemes lay not in the potential for practically unlimited
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expansion of lexicons, but rather in the function of phonemes as decontextualized or de-semanticized indexical units for mental storage and retrieval. There is not space here to explain all of my arguments in this matter. Suffice it to say that, with LeCron Foster (1978), I envisage a time when human speech sounds were all, or nearly all, motivated or with semantic significance, such as to leave worldwide sound-symbolic traces. That until phonemicization had become the rule, speech had been much slower owing to the lower efficiency of lexical search and retrieval, is my own hypothesis. But perhaps there would have been a more fundamental difference between pre-phonemic and fully phonemicized language. Although human thought can operate without language, for which there seems to be adequate psychological evidence, it is far more effective when coupled with language. However, to the extent that phonemes contribute to the speed and precision of overt speech, they must also contribute to inner speech, or internal self-dialog. Thus, prior to the remodeling of speech along phonemic lines, human cognition in general would have been seriously handicapped, and cultural evolution significantly slower. Thus, I would recommend the simulation or modeling of nonor pre-phonemic spoken languages, in order to represent the conjectured earlier stages of language evolution. Unfortunately (but see below), we cannot expect much help in this undertaking from professional linguistic scholars, most of whom seem as averse to glottogonic theorizing as fundamentalist theologians are to biological evolution, and perhaps for some of the very same reasons. 3. One of the doctrines dear to most linguists, although it was promulgated nearly a century ago, is primacy of syntax over semantics — that is, that the core of language lies not in the body of meanings accumulated in the lexicon of this or that language, but in the body of rules for combining morphemes, etc. Bickerton's 1981 book, in its focus on Creoles, flies in the face of still another strongly held dogma — namely, that natural languages cannot be ranked in terms of their fundamental complexity or ease or difficulty of acquisition. It is true that in the earlier nineteenth century, many scholars believed that the languages of 'primitive' peoples were simplistic or crude, representing survivals of more ancient stages of language evolution. In reaction or over-reaction to this, most twentieth century linguists have adopted a kind of linguistic egalitarian-
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ism. The phenomena of lingua francas and Creoles, with their reduced syntactic structure, and lexical limitations (cf. Tok pisin as compared to standard English) have threatened this dogma of the absolute equivalence for all purposes of the world's languages. There is, to be sure, an ethnological analogue of this position, which insists that there is no way to grade cultures on scales of complexity or institutional elaboration. My recommendation here may be unpopular in some circles. I think we must give up the view that mankind has not progressed cognitively since the earliest australopithecines, or that it is 'racist' to consider the possibility that even Neanderthalers, with their wellmade lithic tool-kits and deliberate burials, etc., might have been a little retarded, by modern intellectual standards for mankind. It is strange that the notion of cultural progress should be regarded as a reactionary stance. It seems possible that even over the past 40,000 years or so, languages have gained conceptual and expressive capacities not available to Chatelperronians, and that linguistic progress may even have occurred in the ten millennia which separate us from the end of the Pleistocene. I should insist here that progress can be both biological and cultural; it seems quite likely that linguistic progress for the past 40,000 years has been mainly cultural, just as the improvements in writing over the past 5,000 years, if we are willing to admit that progress has occurred, have been cultural rather than genetically based. I contend that we must acknowledge the probable cognitive deficiencies, compared to ourselves, of earlier, smaller-brained hominids, and even of larger-brained predecessors whose vocal tracts did not permit them to produce fluent, articulate speech. 4. Recent research on in utero learning, in human fetuses, and also in other mammalian fetuses, suggests an extremely interesting line of research bearing on glottogenesis. Studies of human fetuses indicate that during late pregnancy, fetuses overhear or eavesdrop on maternal speech — not of course with semantic understanding, but that they attend to features of acoustic frequencies and prosodic patterning, and that this effect can be measured in neonates by means of the sucking rate (on dry laboratory nipple devices). Fetuses also hear visceral noises in utero, and of course react to very loud external sounds as well, though not to the voices of persons other than their own mothers. For two to three months prior to delivery,
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fetuses receive sounds through the amniotic fluid, including the probably rather muffled sounds of their mothers' speech. After birth, and without experience which might explain their greater attention to their own mothers, they attend much more closely to their own mother's utterances, including tape-recorded versions thereof, and much less to the voices of others, even of female adults closely matched with respect to vocal range. These experiments have been undertaken without any reference to glottogonic theory, but they seem to open up a previously unsuspected dimension to the issues of nature versus nurture with respect to language. It is obvious that only sound-based language, not gesture, can have such effects in utero. Fetuses cannot monitor the visual aspects of gestural communication, and it seems reasonable to suppose that while random vibrations or jarrings of the fetus might accompany strenuous gesticulation on the part of the mother, no coherent record of such gestures would be imprinted on the fetal brain. More to the point, neonates exposed to pre-natal speech would detect direct acoustic resemblances to what they had overheard in the womb; we cannot suppose that neonates can transpose the vibrations and jarrings transmitted through the uterus to what they see in the outside world in the form of visible gestures. Human speech, it would appear now, does not impinge on a new-born tabula-rasa, but rather on an individual predisposed to attend to the nuances of speech in a particular spoken language, as well as to human speech in general. If these recent findings can be substantiated, the normal human infant emerges into the world with a head-start on speech acquisition, even though it requires a year or so for this to manifest itself. If human language had been only gestural for a long period, or even some sort of mixed gestural-vocal proto-language, delivered haltingly and infrequently, tabula-rasa would indeed have been the early hominid condition with respect to language. This could well help to explain the extremely long, practically flat profile of cultural progress before the latter part of the Lower Paleolithic, and the relatively slow increment in brain volume, from a half to a third less than the volume of recent human crania. My own (and probably premature) interpretation of the pre-natal learning data, as so far reported, would be that the prenatal head-start effect of language did not get very far until fully phonemicized speech prevailed. Fetal eavesdropping on maternal speech would constitute the first directly
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effective feedback from any aspect of culture to pre-natal hominids. Tool-making and tool-using would not have involved any such feedback. Ironically, Chomsky's (1968) postulated "language acquisition device" might turn out to be not some handy outcome of random mutations, but at least partly the result of pre-natal learning, laying the post-natal foundation for more rapid speech acquisition. 5. Valuable as I believe the ape language experiments to be, I would urge glottogonic experimenters to reexamine the linguistic capabilities of certain domestic animals, particularly dogs — a topic largely abandoned to anecdotalists since the time of Romanes (1888) in the late nineteenth century. Dogs are abundant, and readily recruitable for nonintrusive experiments on the extent of their understanding of vocal communication, and avoidance of the Clever Hans effect is not, contrary to Sebeok (1981), an impossible condition. 6. Although the LANA experiment in ape language did employ a large (and very costly) computer, designed in the early 1970s, computer technology and software have come a very long way from the start of the LANA project. Small, relatively inexpensive microcomputers have become commonplace, with capacities for graphic displays and full color far exceeding anyone's dreams as of 1970 or even 1975. Moreover, elaborate simulations have been achieved for natural language in recent years, and there is now a full-fledged sub-field represented by the contributions in the American Journal of Computational Linguistics, significantly now only in its tenth year of publication (1984). The world is now full of highly competent and creative programmers, some of whose talents and ideas should be attracted to the fundamental problems of language evolution, even if only as an avocational sideline. Now that we have enormously capable computer graphics systems, I should like to see a conjunction of ape-language experiments and computer graphics, either as training programs, or for direct language communication. 7. My final recommendation may seem superfluous. However, I feel that many highly qualified investigators tend to confine their reading or monitoring of the output of the scientific community to the fields in which they consider themselves professionally compe-
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tent. Such restricted attention probably pays off handsomely — for example, for certain chemists who need only to keep close watch on particular rubrics in Chemical Abstracts, or certain literary scholars who need only to keep track of particular periods in the bibliographies issued by the Modern Language Association. The topic of language origin theory has no such convenient central repository. We must keep our eyes open for relevant information in a very wide range of scientific and scholarly subjects, so far as we are able. References American Journal of Computational Linguistics. Bickerton, D. 1981 The Roots of Language. Ann Arbor: Karoma. Chomsky, N. 1968 Language and the Mind. New York: Harcourt, Brace and World. Foster, M. LeCron 1978 The symbolic structure of primordial language. In S. L. Washburn and E. R. McCown (eds.), Human Evolution: Biosocial Perspectives on Human Evolution. Vol. 4. 77 — 121. Menlo Park, CA: Cummings. Gans, Ε. 1981 The Origin of Language. Berkeley, LA: University of California Press. Gardner, R. Α., and Β. T. Gardner 1969 Teaching sign-language to a chimpanzee. Science 165. 664 — 672. Hewes, G. W. 1983a The communicative function of palmar pigmentation in man. Journal of Human Evolution 12. 297-303. Hildebrand-Nilshon, M. 1980 Die Entwicklung der Sprache. Frankfurt a. Μ.: Campus Verlag. Hockett, C. F. 1961 Logical considerations in the study of animal communication. In W. E. Lanyon and W. N. Tavolga (eds.), Animal Sounds and Communication. 392—430. Washington, D. C.: American Institute of Biological Science, Publication 7. Krantz, G. 1980 Sapienization and speech. Current Anthropology 21. 773 — 792. Laitman, J. 1984 The anatomy of human speech. Natural History 93(8). 20-26. Lenneberg, Ε. Η. 1967 Biological Foundations of Language. New York: Wiley. Lieberman, P. 1984 The Biology and Evolution of Language. Cambridge, Mass.: Harvard University Press. Lieberman, Philip and E. S. Crelin 1971 On the speech of Neanderthal Man. Linguistic Inquiry 2. 203-222.
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Lock, A. 1980 The Guided Reinvention of Language. London: Academic Press. Premack, D. 1970 The education of Sarah: A chimp learns the language. Psychology Today 4(4). 55-58. 1971 Language in Chimpanzee? Science 172: 808-822. Romanes, G. J. 1888 Mental Evolution in Man. Origin of Human Faculty. London: Kegan Paul. Rumbaugh, D. (ed.) 1977 Language Learning by a Chimpanzee: The LAN A Project. New York: Academic Press. Saussure, Ferdinand de 1959 Course in General Linguistics. English translation of Cours de Linguistique Generale, by W. Baskin. New York: McGraw-Hill. Sebeok, T. A. 1981 The ultimate enigma of "Clever Hans": The union of nature and culture. New York: Annals of the New York Academy of Sciences 364. 199-205. Seidenberg, M. S. 1984 Aping language. Semiotica 44(1/2). 177-194. Terrace, H. 1979 Nim. New York: Knopf. Umiker-Sebeok, D. J. (ed.) 1980 Speaking of Apes: A Critical Anthology of Two-Way Communication with Man. New York: Plenum.
Implication and the evolution of language Andrew Lock
Abstract An outline for how change may be described in terms of possibilities and actualities is put forward. A system is characterized as having an actual state which implicitly contains the possibilities for its future course of elaboration. This characterization is applied to language, and yields a logical sequence for the elaboration of language from nonlinguistic forms of communication. Potential sources of evidence regarding the empirical course of language evolution are interpreted from this sequential model. It seems likely that the capacity for speech emerged earlier than grammatically- andphonemically-organized language.
Introduction Enquiries into the evolution of language are by no means easy. They are not helped by the ephemeral nature of the evidence, nor by conceptual sloppiness in interpreting it. There is little that can be done about the first, but the second is an area in which we can make some amends. One problem is caused by the different interpretations given to the term 'the evolution of langage'. It is variously used by different investigators to mean the evolution of: the capacity for vocalizing (aspects of neurology and anatomy); the capacity for speaking (phonemic organization); for symbolizing; grammatical structure; selfconsciousness; and so on. Further, while evolution is a process in time, it is rarely dealt with as a process in which possibility and potentiality play an important role. In what follows, I will outline a process account of evolution, and how such an account affects the way in which the evolution of language may be conceptualized.
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Describing change When we want to discuss how things change, we need to do two things. Firstly, we need a description of the system at the present time, and secondly, the possibilities that system has for its future elaboration. We need, then, an account of both the actuality and the potentiality of the system. (In a thoroughgoing account, it would become apparent that this introductory distinction is self-contradictory, since the potentiality of a system is a necessary part of its actuality. This complication will be ignored here for simplicity's sake). Such an account is best developed through examples. Example 1: A thought experiment Imagine the time when life forms capable of capturing the sun's energy had just emerged on this planet. These forms (plants) constitute an ecosystem. There exist within that system all sorts of unexploited, yet potential, ecological niches. Some of these niches will be at the same level of energy-capturing as the primitive plants we have already conjured up: terrestrial plant life would be an example. Other niches, though, exist at a different level of energy-capture: for having captured and bound sunlight energy, plants themselves constitute a potential energy source. This is a possibility inherent in the system. Once environmental conditions are ripe (and another of the paradoxes created in this mode of thinking is that those environmental conditions are created by the system itself: organisms create the environments they exist in), animals may evolve to exploit the energy source constituted by plants. When they do, a new system results with new potentialities: the possibilities of unpalatable plants and carnivorous animals, for example; and vultures, scavengers and fleas: all sorts of new, but actual, organisms. There are two important points to draw from this exercise: 1. The possibilities for the system's elaboration have an order to them. Carnivores, for example, cannot be actualized before herbivores. 2. The process of actualization may be described, somewhat colorfully, as follows. Biological forms are the meat and vegetable embodiments and realizations of the ecological niches implied by the system at an earlier point in its elaboration. Animals, for
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example, make explicit in their biological structure the implications of the ecological niche created by the preceding plant community. In sum: a) organisms are biological structures that explicate the implications of their ecology; and b) the order in which these biological explications occur is not random, but obeys a logic inherent in the system. Example 2: A real system Fenton and Fullard (1981) have described the evolutionary relationships that have developed between bats and the moths they prey on. Moths, necessarily, evolved before the organisms that prey on them. Moths thus constitute an energy source for the evolutionary system to exploit. As noted above, the implications of the ecological niche that moths create will determine the biological structure of the organism that evolves to occupy that niche (which is why we often talk about an organism being adapted to its environment). So what is required of an animal to exploit the resource of flying, nocturnal insects? As is well known, bats not only have wings, but they also locate their prey without the use of vision (not a very efficient sense in the dark), but by sonar, a frequency-modulated signal, generally between 25,000 and 60,000 cycles per second, which operates over a range of fifteen to thirty feet. Once bats have this ability, they create evolutionary implications for moths. As Fenton and Fullard (1981) note, the majority of moths (in Canada, New Guinea and Hawaii at least) have evolved a membrane between their thorax and abdomen which vibrates in sympathy to bat sonar frequencies. This is neurally linked to the moth's brain, enabling the reflex triggering of escape behavior. Bats now have a new problem. Some of them have solved it by upping the frequency of their sonar, outside the range of that which moths have become able to detect (the short-eared trident moth of Zimbabwe manages 210,000 cycles per second). This solution puts the ball back in the moths' court. Some moths have managed to 'soup up' their reception, up to 150,000 cycles per second; some use the bat's sonar to locate the position of the bat, and then take last second avoidance; some wait for the located bat to close in, and then produce a shriek of their own ultrasound, effectively deafening and disorienting the bat. As a result, some
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bats have given up on sonar, and fly around noiselessly, relying on the vision they originally evolved sonar to supercede. (And some bats never got into this game at all: they eat fruit, suck blood, or even catch fish with their back legs). Here is a very clear example of a system creating and determining the course of its evolutionary development, and of how each stage in the game is an explication into biological form of the implications established at an earlier stage. Note that this description says nothing about how this evolutionary development might be accomplished: it implies some form of selective advantage and intergenerational transmission; but no more. Because of this, it is a form of description that can be applied without prejudice to nongenetically based systems, as the next example shows.
Example 3: A thought experiment about thought Imagine a time in prehistory when people have just become able to count, perhaps using their fingers, and possess no other mathematical abilities. They know nothing about the implications of the number system. They would not know that fingers 2, 4, 6, 8 and 10 had different properties from 1, 3, 5, 7 and 9 (the difference between odd and even numbers); nor that 3, 5 and 7 were prime numbers, whereas 9 was not; nor that 6 was a perfect number. Yet all these possible forms of knowledge are implicit in the original ability. Further, they would certainly not know about the further implications of any of these implied 'objects.' For example, Goldbach's conjecture that every even number is the sum of two primes could only be explicated after the concepts of even and prime numbers had been rendered explicit. The two conclusions drawn above about biological systems can now be applied to this representative psychological system: it contains inherent possibilities for its future elaboration (its future course is implicit in its current state); and the order of its future elaboration is ordered, some developments being necessary preconditions for others. The same mode of description that was offered above for biological systems is also applicable to mental ones, viz: a) (human) mental structures are the explications at the psychological level of the implications of previous structures. Thus, just as in biology animals are the explications of ecological possibilities into
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meat form, so in psychology cognitive structures are the explication of pre-existing implications into 'mind form;' b) cognitive structures are explicated in particular orders. What has all this got to do with the evolution of language? This approach is helpful to us if we forget, at least for the present, anything that is peripheral to the logic of emerging systems. We need to forget, for example, that language has a medium of expression, usually vocal: for the essential logic of the system the medium is irrelevant, it could be done by toe- or ear-waggling. That brains are involved does not matter much either. Further, it is not necessary to maintain a distinction between ontogenetic and phylogenetic elaboration. This does not mean recapitulation is being invoked, only that the mechanics of elaboration are being sidestepped. What we must do is apply this 'systems ecology' mode of thinking to language to establish what evolution must accomplish. Then we can ask how it has accomplished it — what role brains played, the relative timing of changes, the establishment of preadaptationary sequences, and so on. Language can be regarded, then, as implicit in the systems that went before it. It is, in essence, a system that gives those prior implications an explicit form. But where do those initial implications come from? Both Mead (1934) and Volosinov (1973 [1929]) consider meaning to be present in social interaction, and "language simply lifts out of the social process a situation which is logically or implicitly there already" (Mead, 1934: 79). This view has been explored elsewhere with regard to the ontogeny of language (e. g., Clark, 1978; Lock, 1980). Here it is useful to give a summary outline, for given our sidestepping of the recapitulation question, the logic of development will provide a handle on the logic of evolution.
The logic of language development Here are some assumptions about being a newborn infant: (1) at birth, infants do not possess any knowledge about their needs, nor the 'objects' that satisfy them; (2) they have some needs which they cannot satisfy on their own;
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(3) they being in (4) they (5) they
can distinguish between being in a state of need and not one; have a memory; can use their memory to inform their perception.
Now, another thought experiment: imagine being a newborn baby. Having no longer any placental symbiosis with another organism, you are about to experience hunger for the first time. Having no knowledge, you will not know what that feeling is, only that it is unpleasant. Even if you knew what it was, and what was needed to alleviate it, you would be unable to satisfy your need from your own resources (remember, newborns are pretty helpless). What you need is someone else to do something for you. But given your lack of knowledge, you neither know that anyone else exists, nor that they could help you. Thus, drawing on your own resources, you could not communicate with them, even if you knew what you wanted, which you do not. But all is not lost, because you are able to distinguish between being and not being in need; and because your biology ordains that being in need makes you cry. Neonate biology is miraculously predicated on the certainty that someone will notice, interpret and act relevantly, though not necessarily immediately, on signs of distress. Out of the interaction of your abilities (above) and their acting, you will be provided with the opportunity of explicating the implications of the social and biological contexts you are part of. Further, our model of change indicates that the order in which you accomplish those explications will not be arbitrary. I suggest that order will be as follows (for a fuller discussion see Lock, 1980, 1981, in press). The immediate and 'wired-in' value of crying for an infant is: (i) "whatever this feeling is, I do not like it" (ignoring the fact that an infant's representation of this meaning will not be in this English form). This implies: (ii) "I want something else." Once somebody does something relevant to (ii), then the next time that state recurs, "I" will be crying with a rather more determinate value: not (ii) "I want something else," but: (iii) "I want whatever it was that happened last time." Notice what is happening here. Past experience creates knowledge, expectations that guide future action. "I" will begin to have a clearer and clearer
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knowledge of what "I" want. "I" will know, perhaps, that "whatever it was that happened last time" is really "sucking on a bottle." "I" will begin to recognize bottles as objects with particular values. "I" will begin to cry with the meaning: (iv) "I want a bottle" and will be able to stop crying when "I" see that "I" am likely to get one. "I" am creating explicit knowledge, and accidentally conveying that "I" am through "my" actions in the world. The progress of explication can be gauged by the number of implications of an action that are controlled by the individual. "I" do not at this point, for example, give evidence of controlling the implication: (v) "If I want a bottle, you must give it to me." This will come later, and "I" will provide evidence of controlling it when "I" aim my actions at others, rather than directly at the desired object. It is at this point that "I" can first be considered as a deliberate communicator. We have, then, a hierarchy of implications that are sequentially made explicit in the development of the ability to communicate. Further, a similar implicational hierarchy can be elucidated underlying the emergence of the ability to code these communications into language. Early child speech, for example, is tied to the child's own actions: the child may use words in contexts where he or she is acting on an object, but not when another is. Usually this is explained by saying the child is egocentric. Here a different explanation can be offered. Briefly, the implication: (vi) "I am acting on an object" is lower in the hierarchy of implications than: (vii) "You are acting on an object." Further, the passage from (vi) to (vii) is conducted via an intermediary set of implications stemming from (vi), viz: (viii) "If I am acting on an object, then the object is being acted on." If, then, an object is moving and I am not the actor, another agent (you) must be acting on it. Notice here that the explication of these implications is simultaneously the creation of a decentered, propositional mode of coded communication: the process of explication thus creates the basic structure of language. Explication is a continuing process, since each act within it will establish new possibilities for explication. A cognitive system will thus come to have more possibilities for controlling the implications it establishes as it is continuously elaborated.
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Presently we have only a hazy understanding of how explication is accomplished. The ability to break events down into parts and then see the similarity between parts from different events is obviously fundamental. So, likewise, is the ability to remember those parts, and imitatively mark them with parts isolated from the stream of adult speech (see Bates et al, 1979, for a fuller discussion). Such abilities themselves have a developmental and evolutionary history. It is our ability to identify the component skills enabling explication that allows us to understand the processes of language development and evolution, for as Bates et al. (1979): 31) note: "Language can be viewed as a new machine created out of various cognitive and social components that evolved initially in the service of completely different functions." Let me give an example of how we can use this approach in making informed speculations about the course of language evolution. (I will not talk much about the explication of implicational hierarchies here; but the example assumes and is informed by the context developed above). In this example, we do not need to consider the emergence of language as a single event, but as a set of separate developments with separate histories, that at some point are able to come together. This is because the cognitive and social components mentioned above appear, at least in ontogeny, to be modality-free. Obviously, we cannot know if this was the case phylogenetically. However, if it was, then an account of language evolution is possible. So, an example.
Part-whole analysis and language evolution There are two occasions in the archeological record where human artifacts yield evidence of accomplishments in cognitive skills tied to part-whole analysis. Firstly, Wynn (1979, 1981) has conducted analyses of stone tools to elucidate the cognitive abilities of their makers. One of the tools he analyzed was a stone hand axe, dated at 300,000 B. P., which is symmetrical in three planes simultaneously. This requires of its maker an ability to hold the entire intended shape in mind (the whole) when deciding where to remove the next flake (the part). From a much more detailed and compre-
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hensive analysis, Wynn is led to the conclusion that "essentially modern intelligence was achieved 300,000 years ago" (1979: 371). It is interesting that a similar date is given by Laitman (1983) for the likely onset of the ability to speak, based on his studies of the evolution of the human upper respiratory structures: "the line leading to modern man... probably acquired an upper respiratory system similar to ours by 300,000 to 400,000 years before the present. The vocal tract anatomy necessary for the production of the full range of human speech sounds was thus probably also present by this period" (1983: 13). Secondly, the date 50,000 B. P. also figures in the relevant literature. Krantz (1980: 774), for example, notes that: "Cultural evidence on a worldwide scale indicates that something unprecedented was occuring at about this time. Without going into detail or worrying about exceptions, the evidence can be summarized briefly as follows: a) Tools became more sophisticated, suggesting that more learning was involved in their manufacture, b) Tool types became more geographically localized, specific techniques being developed for local circumstances, c) Stone-tipped projectiles became common everywhere. (Earlier 'points' are mostly thick-based and almost impossible to haft), d) Fire using and cave dwelling became common everywhere, not just in colder climates, e) Technological changes began to occur more rapidly..." There have been a number of proposals (see, for example, Hewes, 1980: 781; Krantz, 1980: 775) that language abilities may have something to do with these explosive cultural developments. Recent work by Reynolds (e. g., 1983) helps us get a clearer picture of what underlay these changes Reynolds' work is quite wide-ranging, but it is his investigations of constructional skills in apes and humans that is important in this context. Further, it is a correspondence he has established between constructional skill and language ability that is important. Reynolds (1983: 1) notes that only human constructions incorporate what he calls "external grip", i. e., "the ability to join one material object to another in order to make a new object (such as a spear with a new point) that can be rotated in space as if it were a single object. Apes, in contrast, apparently have only externalized support, in which one object rests upon another in a gravitational field but the new construction cannot be rotated as a unit (such as a stack of boxes)."
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What if the cognitive ability underlying this capacity were modality-free (cf. end of previous section)? We may hypothesize that apes would be unable to manipulate any composite constructions as single wholes, whereas humans could. In language, a grammatical phrase is a composite construction that is treated as a single item by transformational rules. Thus, it is unlikely that we should find true grammatical operations in 'linguistic' apes, because "since the lexical units of ape sign language cannot be glued together with external grip, transformations, which rotate objects into new composite configurations, would not apply; and Terrace (1979) is probably correct in asserting the absence of genuine syntax in apes" (Reynolds, 1983: 20). Further, Hewes (1984) has pointed out the importance of phonemic organization in the sound structure of language: that meaning-carrying vocalizations are composed of separate sounds which are themselves meaningless. Words are constructed as whole units from the manipulation of phonemes by phonological rules, requiring the same abilities evinced in the external grip. To summarize the main points from the above: 1. Basic human intelligence of a modern nature was established about 300,000 B. P. (Wynn, 1981). 2. The anatomical basis for speech was established about 300,000 B. P. (Laitman, 1983). 3. Many anthropologists regard 50,000 B. P. as a likely date for language (which is at odds with 1 and 2). 4. Objects which implicate external grip (Reynolds, 1983) in their construction appear from around 50,000 B. P. (Krantz, 1980). 5. The ability to use both grammatical and phonological rules may well depend on the same underlying abilities as external grip constructions.
Some conclusions Bates' et al. (1979) point (above) was that language is a collage concocted from separate parts. A point to be drawn from the outline of an implicational approach to systematic change is that of future developments being made possible by earlier ones. In more estab-
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lished terminology this would come under the topic of "preadaptation." Taken together, these points and those just listed in summary form lead to the following hypotheses about the course of language evolution. 1. Some form of communication more sophisticated than the emotively-based repertoire common in the social primates was probably necessary for the maintenance of the tool-constructing cultures of our early forebears. This is unlikely to have been a sophisticated vocal form, since the requisite anatomy appears much later than tool cultures. Plooij's (1978) work showing the use of simple gestural (manual and vocal) communication systems in wild chimpanzees suggests such abilities as a likely candidate. We know in human prelinguistic development that these abilities can become quite complex and efficient. 2. At some point, evolutionary pressures began to shift such systems to more and more reliance on the vocal medium. We may only guess at what these pressures were. The anatomical evidence suggests that a good vocal ability was present by 300,000 B. P. 3. The inherent potentialities of this system were not unlocked until 50,000 B. P. with the advent of grammatical and phonemic principles for controlling verbal rather than vocal communication. 4. Changes in cultural and ecological aspects of human social organization since that date have accumulated as the inherent possibilities of the modes of thought facilitated by this efficiently-handled symbolic representational system have been explicated (cf. the example of the number system used above). This last point requires a lengthier treatment than space allows. Finally, it is important to note that these hypotheses about language evolution are predicated on an analysis of the principles of devising a language system. These principles are independent of the mechanics of their accomplishment. We thus define the outlines of the problem, and are able to interpret the archeological record, rather than be dictated to by it. References Bates, E., L. Benigni, I. Bretherton and V. Volterra 1979 The Emergence of Symbols: Cognition and Communication in Infancy. New York: Academic Press.
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Clark, R. A. 1978 The transition from action to gesture. In A. J. Lock (ed.), Action, Gesture and Symbol: The Emergence of Language. 231 — 257. London: Academic Press. Fenton, Μ. B. and J. H. Fullard 1981 Moth hearing and the feeding strategies of bats. American Scientist 69. 266-275. Hewes, G. W. 1980 Comment. Current Anthropology 21. 781-782. 1984 The invention of phonemically-based language. In A. J. Lock and E. Fisher (eds.), Language Development. 49—57. London: Croom Helm. Krantz, G. 1980 Sapientization and speech. Current Anthropology 21. 773 — 792. Laitman, J. T. 1983 The evolution of the hominid upper respiratory system and implications for the origins of speech. In Eric de Grolier (ed.), Glossogenetics. The origin and evolution of language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 63 — 90. Chur, Switzerland: Harwood Academic Publishers. Lock, A. J. 1980 The Guided Reinvention of Language. London: Academic Press. 1981 The early stages of communicative and linguistic development: Underlying processes. In B. de Gelder (ed.), Knowledge and Representation. 94—110. London: Routledge and Kegan Paul. (in pr.) Underlying processes in the elaboration of language. In E. S. Gollin (ed.), The Evolution of Adaptive Behavior. Hillsdale, NJ: Erlbaum. Mead, G. H. 1934 Mind, Self and Society. Chicago: Chicago University Press. Plooij, F. X. 1978 Some basic traits of language in wild chimpanzees? In A. J. Lock (ed.), Action, Gesture and Symbol: The Emergence of Language. 111 — 131. London: Academic Press. Reynolds, P. 1983 Ape constructional ability and the origin of linguistic structure. In Eric de Grolier (ed.), Glossogenetics. The origin and evolution of language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 185 — 200. Chur, Switzerland: Harwood Academic Publishers. Terrace, H. S. 1979 Nim: A Chimpanzee Who Learned Sign Language. New York: Knopff. (Cited by Reynolds, 1983). Volosinov, V. N. 1973[1929] Marxism and the Philosophy of Language. New York: Seminar Press. Wynn, T. 1979 The intelligence of later Acheulian hominids. Man 14. 371 — 391. Wynn, T. 1981 The intelligence of Oldowan hominids. Journal of Human Evolution 10. 529-431.
Perceptual bases for the evolution of speech Richard M. Warren
Abstract It is suggested that speech perception is based upon a holistic recognition of complex acoustic patterns, and does not require the ability to identify individual component sounds. Much confusion in the literature is associated with attempts to consider that speech perception requires the ability to recognize phonemes and their orders at some level of perceptual organization. There is evidence that our ability to recognize acoustic patterns holistically is shared with other animals, and that speech perception evolved from this prelinguistic ability. It appears that identification of component sounds and their orders is a linguistic skill which is the consequence of, not the basis of, speech recognition.
Introduction Before we can begin to trace the evolution of speech and language, it is necessary to understand the nature of mechanisms used for speech perception. Unfortunately, a pervasive emphasis upon phonemes as linguistic units has impaired our understanding the nature of speech perception and its development from auditory capabilities of our prelinguistic ancestors. This paper will attempt to demonstrate that: 1. The concept of phonemes as units of speech can be traced back to the invention of the alphabet. 2. The term 'phoneme' as used today has multiple meanings (articulatory, acoustic, perceptual, and graphemic), and the use of the same term for different entities has led to considerable confusion along with inappropriate theories of speech perception. 3. Sound patterns consisting of sequences of several acoustic 'phonemes' serve as units of organization in speech perception.
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4. Animals other than man are capable of differentiating between complex acoustic sequences, including those of speech. 5. The emphasis placed by some theorists upon the lack of speechproducing capabilities of nonhuman primates and other animals may not be directly relevant to an understanding of the differences in linguistic capacity between humans and other creatures. 6. While human languages have evolved as a form of acoustic communication, these languages can readily be extended into nonphonetic acoustic modes, as well as a number of forms employing sensory modalities other than hearing. A cross-modality comparison of the modes of linguistic communication should be useful in understanding the essential characteristics of human language.
Multiple meanings of the term 'phoneme' The use of the same term to describe different entities can impair the development of a science. In a recent paper (Warren, 1983) I have attempted to show that there are four different uses of the term 'phoneme': a) The articulatory phoneme refers to units employed in the production of speech; b) the acoustic phoneme refers to units employed to classify the sounds of speech; c) the perceptual phoneme refers to units employed in the auditory organization of heard speech; d) the graphemic phoneme refers to the written symbol employed to designate any or all of the other three classes of phonemes. As we shall see, the lack of correspondence between entities bearing the same name has caused great confusion concerning the nature of speech, and this confusion has implications for theories concerning the evolution of speech. The alphabet and its relation to graphemic and articulatory phonemes The concept that speech can be analyzed into a sequence of phonemes can be traced back to alphabetic writing (for discussion, see Warren, 1983). Unlike other forms of writing, the alphabet seems to have been invented only once, and to have spread rapidly to other cultures. The alphabet is based upon articulatory activities employed in generating speech. It was an insight of considerable
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utility to consider that there are a limited number of ways of producing sounds used in a particular language, and that by using a separate written symbol for each of these sound-generating activities, it is possible to transcribe speech as a sequence of articulatory gestures. Note that I have described this alphabetic analysis of speech in terms of articulatory activities rather than sounds (the evidence for and the significance of this distinction will emerge shortly). It is possible to analyze and tabulate these activities readily by direct observation involving oneself and others. The positions employed for consonants are in general easiest to observe, and historically consonants were transcribed by graphemes first. The manner of producing vowels is not as readily observable, and early alphabetic writing did not include symbols for vowels. Writing with a full alphabet of consonants plus vowels, permits an unfamiliar word to be pronounced, since the string of graphemes not only represents the word but provides instructions for its production. Of course, the graphemes used for languages such as English may diverge considerably from current pronunciation. However, it is still possible for readers to pronounce many unfamiliar printed English words with some degree of accuracy. Other languages have maintained closer correspondence between orthography and pronunciation than English and, as we know, the 'phonetic' alphabet employs a series of graphemes designed especially to correspond closely to spoken language. Differences between articulatory phonemes and acoustic phonemes (speech sounds) It is often assumed that every articulatory phoneme has a corresponding acoustic phoneme. However, devices capable of analyzing speech sounds acoustically have indicated that this assumption is false. The lack of correspondence between articulatory phonemes and their acoustic consequences has resulted in what Klatt (1979) has called the "acoustic-phonetic non-invariance problem." To take one example, the acoustical nature of the articulatory phoneme /d/ in /di/ is quite different from the acoustical nature of the /d/ in /du/ (see Liberman, Cooper, Shankweiler, and Studdert-Kennedy, 1967). The great effects of neighboring speech sounds upon the nature of acoustic 'phonemes' are evident when attempts are made to read sound spectrograms which display the results of a spectral
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analysis in visual form. The sound spectrograph was developed in the 1940s by the Bell Laboratories in the hope of enabling the deaf to understand speech through vision (Potter, Kopp and Kopp, 1947). However, even with considerable practice, it is not possible to use such a display for real-time perception of speech, due to the varied acoustic forms of the same 'phonemes.' Nevertheless, there are those who maintain that although some acoustic characteristics of a speech sound change with context, there may be other invariant cues (not readily apparent through acoustic analysis), which are used by listeners for identification of acoustic phonemes (see Jusczyk, Smith and Murphy, 1981; Stevens and Blumstein, 1981).
Is there a perceptual phoneme? Most theories of speech perception have assumed the existence of phonetic units at some level of auditory analysis (for discussion, see Warren, 1982, 1983). However, there is now considerable evidence that phonetic analysis is not necessary for speech perception, and probably does not take place as a precursor to comprehension. Many of the persistent and ingenious attempts to demonstrate the invariance of acoustic phonemes result from the need to use such entities for phonetically-based perceptual theories. But if there are no phonetic perceptual units, then this need vanishes. Let us examine some of the evidence that phonemes are not units for the perception of speech. It has been shown that before children can read, they have great difficulty in segmenting words into speech sounds corresponding to phonemes or graphemes (Calfee, Chapman and Venezky, 1972; Gibson and Levin, 1975; Gleitman and Rozin, 1973; Savin, 1972). Once children have progressed to reading in school, then division of words into phonemes becomes possible (Liberman, Shankweiler, Fischer and Carter, 1974). It might be considered that the facilitation of phonetic segmentation results from developmental changes and increased linguistic skills rather than the acquisition of reading ability. However, Morais, Bertelson, Cary and Alegria (1986) reported that adults who had never learned to read could not recognize, delete, or add phonemes to words, while other members of the same population of illiterates could perform these tasks involving phonemes following training in special adult reading classes.
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Another line of evidence indicating that phonemes are not employed as perceptual units is provided by reaction time studies. It has been shown that the time required to react to phoneme targets in syllables is greater than the time required to react to the syllables themselves (Savin, and Bever, 1970). These results suggested to Savin and Bever that the phoneme may be derived from prior identification of the syllable, rather than serving as the unit requiring identification before the syllable can be recognized. Support for this view was afforded in a study by Warren (1971) in which prior syntactic and semantic contexts within sentences were manipulated to vary the probability of occurrence of target words. As anticipated, a more likely word was identified more quickly. However, the point of interest for this discussion is that a contextually facilitated reaction time to a word, as measured for one group of subjects, was associated with a similar facilitation of the reaction time to an individual phoneme target within that word, as measured for a separate group of subjects. This is in keeping with the hypothesis that phonemes are derived perceptually from words, not the words from phonemes. Consequences of nonphonetic theories of speech perception for theories of speech evolution If we rid ourselves of the belief that speech perception rests upon special processing requiring the identification of component phonemes and their orders, then several questions suggest themselves, such as whether equivalent rules govern the perception of acoustic patterns in other animals, and whether the rules governing speech recognition also govern the recognition of nonverbal patterns in humans. A number of investigators have shown that nonhuman animals could be taught to discriminate between different isolated phonemes and between different syllables. Thus, it has been shown by Dewson (1964) that cats can learn to distinguish between the vowels "ee" and "oo" whether spoken by a woman or a man. Kuhl and Miller (1978) taught chinchillas to discriminate between the voiced and unvoiced consonant pairs represented by /kah/ and /gah/, /pah/ and /bah/, and /tah/ and /dah/. Warfield, Rubin and Glackin (1966) reported that cats could be taught to discriminate between /cat/ and /bat/, and that the limit of acoustic distortion permitting discrimination was similar for cats and humans. Since it
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cannot be argued that these animals appear to have evolved genetically determined mechanisms specialized for human speech sounds, these studies must be tapping some general mechanisms for detection of acoustic sequences. It has been suggested that humans and other animals possess mechanisms for perceiving complex patterns holistically, so that the pattern is recognized as an entity without the need for analysis as a sequence of identifiable items in a particular order (for a discussion, see Warren, 1982). Studies of sequences of hisses, tones, and buzzes have helped to demonstrate that we share the ability to recognize complex acoustic sequences holistically with animals, and that this ability serves as the basis for the perception of speech.
Holistic pattern recognition in humans Several studies have demonstrated that humans can discriminate between permuted orders in otherwise identical sequences consisting of nonspeech sounds, even when the acoustic components are too brief to be identified. Efron (1973) and Yund and Efron (1974) have found that listeners could distinguish between 'micropatterns' consisting of permuted orders of two-item sequences (for example, two tones), when the separation between the sounds was only one or two msec. Listeners appeared to discriminate on the basis of qualitative differences, and could not identify the order of components. These observations were confirmed in essential details by Wier and Green (1975). Two-item sequences are rather special, and the use of iterated sequences of three or four sounds was introduced by me as a way of studying the perception of continuing sequences consisting of only a few items (Warren, 1968; Warren, Obusek, Farmer and Warren, 1969). It was found that three- or four-item 'recycled' sequences of nonverbal sounds require at least 200 msec/item for identification of the order of items, yet it is possible to distinguish readily between different arrangements of the same sounds down to five or ten msec/item whether subjects are trained (Warren, 1974a) or untrained (Warren, 19746). While discriminating between permuted orders of brief items is accomplished on the basis of qualitative or holistic perceptual differences, the ability to discrimi-
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nate between different orders of items having durations longer than a few hundred milliseconds appears to rest upon the linguistic skill of naming items in their appropriate order, and remembering this sequence of names (Warren, 1974a; Teranishi, 1977). We shall return to the use of verbal mechanisms for discriminating between different arrangements of long-duration items later, when we discuss sequence perception in animals other than humans. At this point, it should be noted that there is no upper limit for item durations permitting discrimination of permuted orders in humans.
Holistic pattern recognition in nonhuman mammals A few studies have examined the ability of nonhuman mammals to distinguish between permuted orders of discrete sounds. While each of these studies has found that the animals employed could discriminate between permuted orders of sounds having brief durations, it was observed that a breakdown in the ability to distinguish between different orders of the same items occurred when the item durations exceeded more than a few seconds. Dewson and Cowey (1969) taught monkeys to discriminate between the four possible pairs of sounds which can be generated using a tone and a hiss (tone-hiss, hiss-tone, hiss-hiss, tone-tone) when items had durations of less than about 1.5 sec. At item durations of three sec and greater, the monkeys could not perform the task, and it appeared that they were unable to remember the first item after the second item ended (they were not permitted to respond until the sequence was completed). Monkeys are primarily visual rather than auditory, and their failure to master the task at longitem durations might be attributed to a general difficulty with auditory tasks. However, a similar experiment was carried out using the dolphin (Thompson, 1976), a creature generally considered both highly intelligent and primarily auditory rather than visual in its normal activities. Four sounds, which can be designated as A, B, C, and D, were used to construct sequences of two sounds which were presented through hydrophones. The dolphin was rewarded if it pressed one paddle following the sequences AC or BD, or if it pressed a different paddle following the sequences AD or BC. The sounds had a fixed duration, and a silent period of variable length
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was inserted between the first and second sounds of the pairs. In order to respond appropriately, the dolphin needed to remember the first sound until the second sound occurred. Thompson reported that nearly perfect performance was obtained when the interval separating the sounds was less than two or three seconds. At longer temporal separations, performance was at chance levels. He concluded that the ability to hear the overall pattern ceased at the upper limit of behavioral discrimination, and that the perception of the overall pattern was required for a correct response. The evidence which has been summarized suggests that speech perception is based upon the ability to recognize patterns of sounds holistically, and that we share this ability with other animals. Our perception of speech does not require the identification of component sounds and their orders — rather the identification of components and their orders within acoustic sequences is itself a linguistic skill.
What is special about human linguistic skills? There seems little doubt that human language originated and evolved as an acoustically based method of communication employing sounds generated by our vocal tract. However, our use of language today does not require conventional speech sounds — whistled languages which remain intelligible over great distances have been developed as an ancillary method of communication in a number of mountainous areas (Busnel and Classe, 1976). Language does not even require acoustic signals: Reading is every bit as rapid and accurate in transmitting linguistic information, and sign languages are used with fluency by the deaf. Languages using visual signs need not correspond directly to a spoken language (as does signed English), but can develop into uniquely visual forms with quite different rules (as does American Sign Language). Language does not even require use of our special distance senses of hearing and vision: The sense of touch can be used by the blinddeaf in communication, and braille permits tactual reading by the blind. Hence, although the development of special sound-producing systems seems to be associated with the evolution of human lan-
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guage, linguistic communication can now operate without the use of sound, when necessary. It seems that our use of language is based upon an ability to manipulate symbols according to learned conventions in an exceedingly complex and versatile fashion. These symbols can consist of auditory, visual, or tactile patterns. It is through the study of this symbol-manipulative ability within and across sensory modalities that we can more fully understand the mechanisms subserving human language and the evolutionary development of speech.
References Busnel, R. G. and A. Classe 1976 Whistled Languages. New York: Springer. Calfee, R., R. Chapman and R. Venezky 1972 How a child needs to think to learn to read. In L. W. Gregg (ed.), Cognition in Learning and Memory. 139 — 182. New York: Wiley. Dewson, J. Η. Ill 1964 Speech sound discrimination by cats. Science 144. 555 — 556. Dewson, J. Η. Ill and A. Cowey 1969 Discrimination of auditory sequences by monkeys. Nature 222. 695-697. Efron, R. 1973 Conservation of temporal information by perceptual systems. Perception and Psychophysics 14. 518 — 530. Gibson, E. J. and H. Levin 1975 The Psychology of Reading. Cambridge, MA: MIT. Gleitman, L. R. and P. Rozin 1973 Teaching reading by use of a syllabary. Reading Research Quarterly 8. 447-483. Jusczyk, P. W., L. B. Smith and C. Murphy 1981 The perceptual classification of speech. Perception and Psychophysics 30. 10-23. Klatt, D. H. 1979 Speech perception: A model of acoustic-phonetic analysis and lexical access. Journal of Phonetics 7. 279 — 312. Kuhl, P. and J. D. Miller 1978 Speech perception by the chinchilla: Identification functions for synthetic VOT stimuli. Journal of the Acoustical Society of America 63. 905-917. Liberman, A. M., F. S. Cooper, D. P. Shankweiler and M. Studdert-Kennedy 1967 Perception of the speech code. Psychological Review 74. 431 —461. Liberman, I. Y., D. Shankweiler, F. W. Fischer and B. Carter 1974 Reading and the awareness of linguistic segments. Journal of Experimental Child Psychology 18. 201 -212.
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Morais, J., P. Bertelson, L. Cary and J. Alegria 1986 Literacy training and speech segmentation. Cognition 24, 45 — 64. Potter, R. K., G. A. Kopp and H. G. Kopp 1947 Visible Speech. New York: Van Nostrand. Savin, Η. B. 1972 What the child knows about speech when he starts to learn to read. In J. F. Kavanagh and I. G. Mattingly (eds.), Language by Ear and by Eye. 319-329. Cambridge, MA: MIT. Savin, Η. B. and T. G. Bever 1970 The nonperceptual reality of the phoneme. Journal of Verbal Learning and Verbal Behavior 9. 295-302. Stevens, Κ. N. and S. E. Blumstein 1981 The search for invariant acoustic correlates of phonetic features. In P. D. Eimas and J. L. Miller (eds.), Perspectives on the Study of Speech. 1 - 3 8 . Hillsdale, NJ: Erlbaum. Teranishi, R. 1977 Critical rate for identification and information capacity in hearing system. Journal of the Acoustical Society of Japan 33. 136—143. Thompson, R. K. R. 1976 Performance of the bottlenose dolphin (Tursiops truncatus) on delayed auditory sequences and delayed auditory successive discriminations. Doctoral Dissertation, University of Hawaii. Warfield, D., R. J. Rubin and R. Glackin 1966 Word discrimination in cats. Journal of Auditory Research 6. 97—119. Warren, R. M. 1968 Relation of verbal transformation to other perceptual phenomena. Conference Publication No. 42, Institution of Electrical Engineers (London), Supplement No. 1. 1—8. 1971 Identification times for phonemic components of graded complexity and for spelling of speech. Perception and Psychophysics 9. 345 — 349. 1974a Auditory temporal discrimination by trained listeners. Cognitive Psychology 6. 237-256. 1974Z> Auditory pattern discrimination by untrained listeners. Perception and Psychophysics 15. 495-500. 1982 Auditory Perception: A New Synthesis. New York: Pergamon. 1983 Multiple meanings of 'phoneme' (articulatory, acoustic, perceptual, graphemic) and their confusions. In N. J. Lass (ed.), Speech and Language: Advances in Basic Research and Practice. Vol. 9. 285 — 311. New York: Academic Press. Warren, R. M., C. J. Obusek, R. M. Farmer and R. P. Warren 1969 Auditory sequence: Confusion of patterns other than speech or music. Science 164. 586-587. Wier, C. C., and D. M. Green 1975 Temporal acuity as a function of frequency difference. Journal of the Acoustical Society of America 57. 1512 — 1515. Yund, E. W., and R. Efron 1974 Dichoptic and dichotic micropattern discrimination. Perception and Psychophysics 15. 383-390.
Part III Fossil evidence
Neoteny and language evolution Bernard H. Bichakjian
Abstract While formal devices can readily be proposed to account for specific linguistic changes, language evolution as a whole and ongoing process has proven to be a difficult and delicate matter. The very notion has been only sporadically recognized, and its explanation left wanting. Responding to this need, the present article attempts to show the unity of evolution across languages, define the direction in which it has been proceeding, and argue that man's biological evolution may suggest an explanation of the linguistic process.
1. Within the framework of the evolution of man Obscurum per obscurius. Using a theory of man's biological evolution, where the veil of mystery cannot be said to be fully lifted, to gain insight into the unexplained evolution of language may, at first glance, strike some observers as a senseless undertaking. Such an endeavor admittedly entails risks; yet, the approach is basically well-conceived. Language does not stand in isolation. It is directly related to our anatomical structure, physiological functions, and cognitive faculties. Given this direct relationship, language evolution can only be understood through the understanding of human evolution as a whole. Before trying to gain this understanding, we must agree on the meaning of language evolution. When anthropologists use this term they refer to the acquisition of speech by our species, but, for a linguist, language evolution is the sequence of changes undergone by languages with the passing of time. Here language evolution will have the second meaning, and language genesis will be used, if need be, to refer to the former.
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It could be asked, of course, whether the genesis of language and its subsequent evolution are two distinct processes. Obviously, between the calls of our apelike ancestors and the speeches of present-day orarors, the line of development is unbroken; however, there must have come a point when the emphasis shifted. During the genesis of language, when grammatical categories and syntactic functions had to be created, the emphasis was on the expansion of conceptual complexity. Once a fairly developed system had been achieved, the emphasis must have shifted to the transformation of the material aspect of language. The trend towards greater conceptual complexity never stopped — today it is visible mainly in the lexical area — and the trend towards lesser material complexity must have existed from the very beginning, but we can study it better during the stage between a reconstructed protolanguage and its contemporary realizations. Language evolution will, therefore, refer essentially to the steady transformation of the material aspect of speech, as observed from the time of a reconstructed ancestral language to the present.
2. The postulates If language evolution is to be studied in the context of man's biological evolution, the linguist will need, on the one hand, a reliable theory of biological evolution and, on the other hand, evidence that the system of communication we call language has a biological basis. These two prerequisites, however logical, raise specific problems. First of all, man's biological evoltution is not explained by one, but several theories, and the biological basis of language, though commonly accepted, remains putative. However, in spite of the diversity of interpretations, and the tentative character of our understanding of the biological data, I believe the linguist can already begin to integrate language evolution in the phylogeny of man. 2.1 Different approaches to biological evolution The evolution of man can be approached from two angles, at least: the geneticists can use their understanding of gene-behavior
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during reproduction processes to reconstruct the long series of evolutionary changes; from the other angle, paleontologists trace the evolution of species by comparing the modifications that morphological features have undergone throughout the ages. Obviously, the comparison of two skulls can never reveal the genetic mechanism that produced, say, the reduction of man's brow ridges, nor, on the other hand, can the understanding of genetic processes account for the fact that in man brow ridges kept evolving along a recessive line. Both approaches, however legitimate and partially fruitful, need complementary explanations. 2.1.1 The "synthetic theory" The geneticists, or the scientists who begin from the molecular data, complement the microevolutionary evidence with Neo-Darwinian considerations. Variations during reproduction occur at random, but whenever the genetic changes confer intrinsic advantages to an organism, or assign characteristics that are advantageous in a particular ecological context, the 'improved' organism survives better or procreates more, while the static members of the species, and a fortiori the bearers of deleterious mutations, decrease in number and eventually die out. The vicissitudes of genetic reproduction, coupled with the natural processes of population selection, constitute the main tenets of the "synthetic theory," and the scientists who believe in it consider it capable of explaining the evolution of all species. While the scientific quality of the laboratory research conducted since the time of the Mendelian experiments has not been disputed, the synthetic theory as a whole has met with a fair share of scepticism. Though the microevolutionary mechanisms are our best available source of empirical data, their extrapolation, like all extrapolations, ist at best indicative, not conclusive, and indicative within the boundaries of our present knowledge. Back in 1940, the much criticized Richard Goldschmidt, who is undergoing a partial rehabilitation (cf. Gould, 19806: 186-193), wrote: "the step from one species to another requires another evolutionary method than that of sheer accumulation of micromutations" (quoted from Henig, 1982: 17). Some forty years later, the issue is still open. "The most sophisticated," according to Gould, "of modern American
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textbooks for introductory biology" addresses itself to the perennial problem with the following question and answer: "[Can] macroevolution ... be explained as the outcome of (these) microevolutionary shifts? ..." The answer is that "it is probable, and no one has come up with a better explanation" (quoted from Gould, 19806: 187). It could also be asked whether a 'how else' explanation is an epistemologically valid one (cf. for the methodological aspect, Lass, 1980: 6 8 - 6 9 , and Lenneberg, 1967: 260). Seeing that the gap between molecular biology and macroevolution remains frustratingly open, Gould (1980a: 119) recently concluded that " 'the modern synthesis', as an exclusive proposition has broken down on both of its fundamental claims: extrapolationism (gradual allelic substitution as a model for all evolutionary changes) and nearly exclusive reliance on selection leading to adaptation." Whether this "breakdown" forebodes the imminent extinction of the "synthetic theory," or whether the orthodox view will survive after undergoing adaptive genetic changes is difficult to tell. Whatever the outcome, the signs of an impending evolution are present. 2.1.2 The pluralistic approach Whereas the adherents of the "synthetic theory" defended the view that evolution is the result of random mutations subjected to the pressures of natural selection, Gould (19806: 15 — 16) advocates a pluralistic approach: "Many evolutionists (myself included) are beginning to ... assert the hierarchical view that different levels of evolutionary change often reflect different kinds of causes. ... The modern synthesis works in its appropriate arena, but the same Darwinian processes of mutation and selection may operate in strikingly different ways at higher domains in a hierarchy of evolutionary levels ... we must [therefore] reckon with a multiplicity of mechanisms that preclude the explanation of higher level phenomena by the model of adaptive gene substitution favored by the lowest level." On the higher levels, and in the case of man in particular, Gould (1977: 405-406) argues that evolution is not so much the result of an alteration in the structural genes, because in this area the difference between chimpanzees and humans is small, but of a change in gene regulation. In the course of man's evolution, the ancestral regulatory genes changed their rates and proceeded to operate a retardatory action that slowed down our general
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development. Because of this general retardatory action, Gould (1977: 375) points out, which affected both his somatic and germinal systems, man evolved, retaining into adulthood the fetal and juvenile features of his ancestor, and eliminating from his ontogeny the corresponding features which, before the change, were acquired late. Thus, with minor modifications, man keeps throughout his life the large head and bulging cranium his ancestor had only as a fetus or an infant, and he does not develop the prominent brow ridges and the protruding jaws, which his ancestor did have in the early part of his ontogeny. In addition to the morphological evidence, which can be presented with great arithmetical accuracy, there are experimental data confirming the role of regulatory genes. Gould (19806: 192) points out that, if we "delay the onset of metamorphosis, ... the axolotl of Lake Xochimilco reproduces as a tadpole with gills and never transforms into a salamander." This, admittedly, is indirect evidence. Direct evidence is more difficult to obtain: "it is notoriously difficult to measure differences in genes that vary only in the timing and amount of their products in ontogeny, while genes that code for stable proteins are easily assessed" (Gould, 1977: 406). Alterations of structural genes are therefore easier to observe than changes in the regulatory system. This technical problem explains why molecular biologists have less data substantiating regulatory changes than they have illustrating gene mutations. The discrepancy will not be eliminated overnight — technological advances are necessary — but the study of gene regulation is the subject of intense molecular research, and already the available results lend support to the hypothesis of man's having evolved from his apelike ancestor essentially through a change in his regulatory system. That is why Gould (1977:365) "believe[s] that human beings are 'essentially' neotenous." 2.1.3 The choice of a theory of evolution Obviously, it is not for the linguist to sit in judgment between the paleotologist and the molecular biologist. Proponents and critics of neoteny do not give this controversial term the same interpretation and, in the mosaic of human evolution, what is neotenous to one is something else to another (cf., for instance, Parker and Gibson, 1979, and the appended "Open Peer Commentary"). The molecular
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data for settling this debate are still wanting, but there seems to be a general agreement that regulatory changes have played a role in the evolution of man's morphology. 2.2 The genetic basis of language Since the present objective is to study language evolution within the framework of man's biological evolution, before starting with the discussion of the linguistic data, we have to address ourselves to the question of whether language has a genetic basis. Evolutionists find this a trivial question, but not all linguists see the correlation as a truism. At any rate, the effort is not entirely vain because, as we seek evidence for the biological correlates of speech, we also uncover the cellular activities that affect them. According to Lenneberg (1967), the evidence is twofold: deductive and inferential. 2.2.1 The deductive evidence Lenneberg's (1967) reasoning starts with the evolution of man. Though his wording is somewhat different, like Gould (1977, 1980a, b), he believed that human speciation is essentially the result of changes in gene regulation. This explanation is crucial, because, if, as it is believed, man -evolved through a timing change in the actions of the regulatory genes, and since speech is a specific feature of human beings, our characteristic faculti de langage must have some genetic correspondent upon which the regulatory genes can act with the new timing and assure its ontogenetic development. Here is how Lenneberg (1967:244) expresses it: "If gene-variations are the raw materials for speciation ... and this is reflected in interspecies differences in ontogenetic history, then a highly speciesspecific feature such as the capacity for language might well be involved in some fashion in species-specific developmental peculiarities." The changed regulation must have worked on preexisting material: "It is ... entirely possible that certain specific principles of categorization and recombination which we encounter again and again in the perception of speech as well as in its production ... are modifications of physiological principles evident in motor coordination. The ability to name may be related to perceptual and modified neurophysiological processes. Certain innate neurophysiological rhythmic activities might have been adapted to subserve in a highly specialized way . . . " (Lenneberg, 1967: 235).
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2.2.2 The inferential evidence To buttress his theoretical argument, Lenneberg (1967: 248—253) presents two sets of observations. First, he quotes reports, showing that, like other types of development, the acquisition of language manifests a much greater synchronism in identical twins than in fraternal ones, and the longer the period of observation, the wider the gap between the two groups. Second, he points out that the inheritance of speech disabilities serves as a sad, but compelling, indication that our potential for language is rooted in our genes. 2.2.3 A biological basis for the study of language evolution In the present study I shall not discuss the origin of language; my concern is with its further evolution. However, since language was probably acquired by man as a result of a timing change in the regulation of preexisting cognitive and communicative faculties, and since, furthermore, the observational data from language acquisition by twins and from pedigrees of speech disturbances add circumstantial evidence for the existence of a biological basis of language, I believe we can not only postulate the putative existence of genetic correlates of speech, but also conclude that these correlates fall under the control of regulatory forces.
3. The evolution of language As we turn to the assessment of the linguistic data, and try further to define language evolution, it seems helpful to keep two distinct biological processes in mind. I shall illustrate them by reference to the phylogeny of the seal. As we know, the seal is a land mammal that has adapted to aquatic life. Now, if for some reason, the seal had to leave its marine environment, it is possible to imagine that, through the combined actions of genetic variations and natural selection, it would undergo organic changes that would make it fit again for an earthbound existence. But what is difficult to imagine is that, for some reason, the seal would revert to a reptile — perhaps via marsupial or monotreme stages — and from reptile to fish, and from fish to amoeba. Two different types of organic changes must
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be considered, therefore: the 'ecological' ones and the hierarchical ones; the former may zigzag with the ecology, the latter are ordered in the direction of greater structural complexity. Although the parallel is not perfect, a comparable distinction must also be made in the evolution of language. Society which, in the case of language, controls the ecological factor, might favor or even introduce certain changes. For instance, the educated French find it fashionable today to geminate intervocalic sonorants (thus po[\\]itique for politique). Some years ago, it was the velarized pronunciation of a that was considered a sign of distinction (cf. also Labov, 1972). Also, a given articulatory habit, whether belonging to bilingual speakers, or adopted by a monolingual community, might cause sweeping changes. It is assumend with reasonable certainty that the extensive diphthongization of vowels, which led to the situation prevailing in Old French, was the result of the lax pronunciation of the Celtic speakers. Conversely, the German Herbst, 'autumn,' in contrast with the English harvest shows the existence among speakers of High German of a distinct phonotactic preference for "hyperclosed" syllables (cf. Malmberg, 1955). Aside from the above changes, which can zigzag, as the French syllable, which went from CVC to CV and back to CVC, or the Spanish s, which became first voiced and later voiceless, there are changes that are not prompted by social pressures or sporadic preferences, although, admittedly, social forces may influence their rate of evolution. I shall call processes such as the ongoing disappearance of long vowels or the gradual elimination of the subjunctive, inherent changes and, in the light of examples taken from IndoEuropean languages, we shall observe that, like their biological counterparts, these changes proceed in a specific direction. This observation is not new. In 1918, Meillet had pointed out that "quand une langue se differencie ... celles des innovations realisees dans chaque parier qui ne tiennent pas a des conditions propres ä ce parier sont ou identiques ou du moins orientees en une meme direction''' (Meillet, 1965: 65; emphasis added). In 1921, Sapir followed suit with his well-known metaphor, observing that language "has a drift" (Sapir, 1949: 150), and arguing that "linguistic drift has direction. In other words, only those individual variations embody it or carry it which move in a certain direction, just as only certain wave movements in the bay outline the tide" (Sapir, 1949: 155). A few years later, Meillet restated his view, adding a
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remark which is especially relevant when we think of language evolution as possibly being the result of a change in the regulatory processes: "Certain des principes du changement sont universels ... et ... a cet egard il n'y a de particulier ä telle ou telle langue que la rapidite plus ou moins grande avec laquelle agissent ces tendances et le detail materiel des changements," but he had to concede that 'Torigine des tendances auxquelles sont dus les changements ... echappe [au linguiste]" (Meillet, 1926: 18 — 19). In an attempt to further our understanding of the origin of these "tendencies," I shall point out that language does not just move inexorably along a line defined in terms that have no explanatory power, but that these inherent changes, which stand central in the evolution of language, proceed in the direction of early-acquired features. This valuable observation will make it possible to argue that, given its pedomorphic course and the putative existence of cellular correlates of speech, language evolution is perhaps also the result of gene regulation. 3.1 The inherent linguistic changes Assessing the inherent changes that Indo-European has undergone during the past six (?) millennia to become the modern languages spoken from Bangladesh to Ireland, and in the territories once colonized by the speakers of these languages, is obviously an impossible task. What I shall try to do is discuss what I believe to be the essential evolutionary changes that have affected the phonology, morphology and syntax of the protolanguage. 3.1.1 The inherent phonological changes Although as rich as those existing in modern languages, the consonantal system of the protolanguage looked, nevertheless, quite different. Whereas today stops are matched with at least one series of fricatives (usually / , s and s and/or x) and sometimes two, IndoEuropean had no less than twelve stops and only one fricative. The large number of stops implies that at least some of them had a secondary point of articulation. According to Gamkrelidze and Ivanov (1973), whose theory is gaining broad acceptance, IndoEuropean had one series of glottalized stops, one series of voiceless stops, with aspirated and plain allophones, and one series of voiced
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ones, with again aspirated and unaspirated variants in complementary distribution. Looking at these stops 'vertically,' we find, next to the labial and dental orders, two orders of velars: one plain and one labialized. In addition to these stops and the fricative s, there was not only the usual score of sonorants, but also a set of laryngeals. Their existence, first posited by de Saussure, was given strong empirical support when an Λ-like sound — perhaps two — was discovered in Hittite. Although the matter has not been settled to everyone's satisfaction, it is commonly thought that Indo-European hat three laryngeals, which can be compared with the Arabic emphatic and laryngeal sounds (cf. Keiler, 1970:68 — 89; and also Winter, 1965). As we look at this bewildering array of sounds, we can see that, with the possible exception of the Indo-Aryan languages, which have kept the aspirated stops and made aspiration distinctive, practically all the complex consonants have been simplified. Laryngeals have disappeared, with the adjacent vowels compensating for their losses with qualitative or quantitative changes. Glottalized stops have become plain voiced stops, changing the intonation (cf. Winter, 1978) or the quantity of the preceding vowel (cf. Kortlandt, 1978). Finally, labiovelars, the losses of which began very early in the (pre)history of Indo-European, are dying a slow death in the Romance languages, while there linger but a few in the Germanic languages (cf. the English quick). Elsewhere they have disappeared. The evolution of the Indo-European vowels is a delicate question. I shall mention two changes that can be accepted without controversy. The long vowels, whether existing originally or produced by the loss of laryngeals, have been gradually losing their quantitative mark, entering into qualitative oppositions with their short counterparts. Next to this easily observed development stands the earlier loss of a process called vowel gradation, apophony or ablaut. We can get an idea of the original interplay between vowels by thinking of the English drink, drank, drunk, but whereas the vowels of drank and drunk are free to occur in the base form (cf. grant and blunt) the Indo-European alternants were bound to given morphological contexts. These restrictions were lifted very early and, today, though not all vowels occurring in the stressed position can appear in unstressed syllables, morphology no longer determines the nature of the vowel.
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Other changes have, of course, taken place. Romance and Celtic languages have created and, with the exeption of Italian, eliminated geminates, the Slavic languages have introduced the distinction between plain and palatalized consonants, but the changes indicated above seem to represent some of the essential features of the phonological evolution of Indo-European. While it is possible for a language to glottalize a consonant (cf. certain pronunciations of English bottle ) or to use vowel length to make some incidental distinctions (cf. French maitre [me:tre] 'master' and mettre [metre] 'to put,' which some speakers make it a point to keep apart), to my knowledge, no Indo-European language has systematically introduced glottalized stops, laryngeals, or labiovelars, nor gone back to the regular use of long and short vowels, or to the mechanism of vowel gradation. In this specific sense, the essential evolutionary changes proceed in a definite direction. 3.1.2 The inherent morphological changes Although no more radical than those observed in phonology, the changes that have affected Indo-European morphology have the advantage of being more tangible. So much so that many of them are almost common knowledge. Thus, many modern languages have completely abandoned the declensions of nouns or adjectives. In this respect, Russian occupies a conservative position, although the situation is evolving in the spoken language. In German, where the paradigmatic changes are essentially born out by the articles, the genitive has been receding steadily and, in unguarded moments, accusatives slip more and more into slots once thought of as being reserved for datives. Along with the reduction and elimination of declensions, two other changes have taken place. The dual was eliminated very early, leaving behind a two-way distinction between the singular and the plural, and many languages have reduced gender from three to two, or completely done away with it. English is a well-known example, but the loss of gender also occurred in Armenian and Bengali. The evolution of verbal morphology proceeded on two different levels. On the one level, certain grammatical distinctions have disappeared or are receding. The optative has become very rare, while the subjunctive is steadily losing ground. The verbal aspects as they existed and functioned in Indo-European have completely
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disappeared, leaving behind in the Romance languages a remnant in the form of the imperfect and in the Slavic languages, as Aitzemüller (1978: 164) puts it evocatively, a "lebendigejs] Gefühl" which became "Grundlage und Triebfeder für die Ausprägung des slavischen Verbalaspekts." Finally, the middle voice has lost its identity in most modern languages. The losses of the modal and aspectual distinctions have been generally compensated for by the growing importance assumed by tenses (cf. the Latin verbal system, where the original subjunctive and optative were replaced by a subjunctive and a future, with the Romance conditional gradually dislodging the secondary subjunctive). Sometimes a lexical alternative has been chosen: the iterative, the inchoative, the causative, etc. are no longer expressed by a thematic infix but by independent verbs or adverbs. On the other level, there are the changes applied to the verb form itself. To have an idea of morphological change, we could think of the history of the French verb chanter 'to sing.' In Latin, it was canit in the present, and cecinit in the perfect. In Indo-European fashion, the perfect was indicated by a vowel change (cf. English drink, drank), and by the concomitant reduplication of the stem. Later the echoing canit, cecinit were replaced by cantat, cantavit, formed on the intensive variant of the verb, which not only belonged to the derivationally active first conjugation, but also allowed the use of the infix -vi- to indicate the perfect, and do away with the original ablaut and stem reduplication. The new morphology assured the invariability of the stem throughout the paradigm (cf. Montgomery [1977] for a comparable change in Modern Spanish). The next step was to substitute an auxiliary for the infix, giving habet cantatus and, today, in French il a chante instead of the original cecinit. The same progression can be observed in the Germanic languages. In Gothic, waian 'to blow' had the reduplicative preterite wai-wö; in Dutch, the cognate form had become woei; subsequently suffixation was to be preferred to ablaut, producing waaide, which, given the growing use of the auxiliary, is in the process of becoming he eft gewaaid. The evolutionary line is clear. The changes went in the direction of an invariable stem and, in most languages, it is subsequently switching to an analytical form. The use of a personal pronoun instead of personal markers is so obvious that it need hardly be mentioned. The evolution of the verbs parallels that of the nouns. Certain grammatical distinctions such as the dual or optative became very
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rarely used, while gender and moods, like the subjunctive, are receding. On the material side, prepositions and articles, on the one hand, and auxiliaries and personal pronouns, on the other, are doing the work of suffixes. Like those observed in phonology, these changes are common to all Indo-European languages. They proceed of course at rates that vary from one linguistic community to another, but the systematic occurrence of the reverse process is never found.
3.1.3 The inherent syntactic changes The evolution of morphology and especially the loss of declensions brings us to the study of syntax. It is a known fact that, as long as the nominative and accusative, especially of animate nouns, are distinct, word order can vary and serve to express stylistic nuances. But when declensions disappear, this freedom is taken away, and the words must be arranged in a fixed order. The emergence of a fixed order as nominal paradigms collapse is common knowledge. What is more interesting is the transition from a nominal to a verbal sentence and from unrelated sentences (parataxis) to correlated, and finally subordinate clauses. The attributive sentence can still be found in some archaic Latin constructions, such as Quid tibi hanc rem narratic est? 'Why are you telling me this thing?' or in a closer translation, 'Why is narrating this thing to you? But the Latin narratio is not a gerund but a fullfledged noun, governing the accusative. This syntactic relationship indicated that, when such constructions were in general use, the umbilical cord between the maternal substantive and the fetal verb had not been cut (cf. Collart, 1975: 37 and 47). We also find this phenomenon in Gothic sentences such as, ha kara unsis 'what does it matter to us,' literally, 'why concern to us.' According to Mosse (1942: 175), "Ce type [de phrase]... est une survivance et on ne le rencontre qu'assez rarement." Along with the birth and the development of the verb came the development of the complex sentence. Originally, there were only strings of simple sentences (cf. the Latin veni, vidi, vici Ί came, I saw, I conquered'). Later, subordinate clauses began making their way. The forerunner of the adverbial and adjectival clauses — especially when the relative pronoun had an indefinite antecedent —
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was the correlative construction, such as the one in the Latin Quod habuit id perdidit, originally, 'something he had that he lost', and later, 'what he had that he lost.' We find such a fossilized structure in German aphorisms like Wer einmal lügt dem glaubt man nicht mehr} literally, 'who once lies that [person] one believes no more.' Finally, in both German and Latin, the order of the two clauses was reversed, and correlation had given way to subordination. In a parallel evolution, appositives appeared and, with the demonstrative gradually acquiring subordinating value, the inserted statement became a relative clause and proceeded to replace the participial construction. Caesar could very well write hunc ex proximis unus iacentem transgressus 'one of his neighbors having stepped over this [soldier] who was lying on the ground,' but today this lying-on-the-ground is impossible (the example is from Collart, 1980: 80). Although less accessible, Sanskrit offers even more vivid examples of participles used where we would normally have a relative clause. Meillet (1964: 374) quotes two verses from the Rigveda, which mean 'he brought out the cows ... displaying those that were hidden,' but he stipulates that the literal translation would be 'he led out the cows ... displaying [those] in hiding being' (and cf. also Chatterji, 1970: 999-1003). Likewise, the participial phrase with an adverbial meaning came to be replaced by the subordinating clause that had evolved out of the correlative structures. The Latin mihi dormienti apparuit Fortuna (quoted from Collart, 1980: 80), literally, 'to me sleeping + dative marker appeared Fortuna' has to be translated today with an adverbial clause: 'Fortune appeared to me while I was sleeping' (more on the development of subordinate clauses in Bichakjian, 1982). In the Indo-European languages, syntax displays a double evolution. On the one hand, verbs and nouns grew into increasingly distinct grammatical categories, and sentences became complex. On the other hand, the marking of syntactic functions shifted from flectional to distributional processes (fixed word order), while correlation gave way to subordination, and adjectival and adverbial clauses came to replace many participial phrases. These changes, like those observed in morphology and phonology are inherent modifications, which to my knowledge have not been observed occurring in the opposite direction.
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3.1.4 Assessing the inherent linguistic changes In biology, the inherent changes proceeded in the direction of greater complexity. A comparable process can also be observed in language, but here there seems to be a need to consider two types of complexity. On the one hand, the development of a well-established verbal category, and the emergence of complex sentences, with relative pronouns and subordinating conjunctions, and later the creation of the extension of prepositions, auxiliaries, articles and personal pronouns, unquestionably led to a greater wealth of grammatical possibilities. Similarly, the gamut of speech sounds was expanded with added vowels and fricatives and new affricates, while voicing was made distinctive. This aspect of language evolution certainly displays a movement towards greater complexity — this is what I called above "conceptual complexity." But language also has a material aspect. Here, the evolution is characterized by changes such as producing s and k instead of k and kw, using prepositions, and ranging words in a given order, instead of applying often idiosyncratic suffixation rules, and making relative clauses, instead of declining already inflected verbal forms. These material changes, which are the primary concern here, have proceeded in a given direction, and the nature of this course, we shall see, has heuristic value.
3.2 The direction of inherent changes Having found a constant in the evolution of language, we must now attempt to define this constant in terms that have explanatory power. Stating that languages tend to become analytical is no error from an observational point of view, but concluding that, because they move from a synthetic to an analytical state, languages tend to become analytical is just to restate the explanadum, not to offer an explanans. If, however, we attempt a definition of language evolution in terms of language acquisition, we might obtain data that would lead us to an acceptable explanation. Establishing a chronology of acquisition for the variety of forms that the inherent changes have created in the Indo-European languages presents a certain number of problems. First of all, the scope is gigantic; however, since the direction is everywhere the same, what is true for language A can often be generalized to
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language Β. Secondly, it is difficult to say when an Indo-European child acquired a given sound which was well integrated in the ancestral system, whereas a comparable one in a modern language may, because of its lesser frequency, appear in a different stage of development. Finally, even for the features which occur regularly in modern languages, the period of acquisition may vary, or their appearance may not have been observed. Obviously, more research is needed; yet, in spite of these problems, there seem to be sufficient data to allow one to assess language evolution in terms of language acquisition. Starting again with phonology, we may observe that labiovelars were often eliminated via the palatalization of the corresponding velars, that is, by substituting k and s for kw and k. Since k is common to both systems, the acquisition of s must be weighed against that of kw. The result of such a comparison is clear: s is acquired long before kw (van Ginneken, 1917: 55 and 205 — 206; for the early acquisition of s, see also Ingram, et al., 1980: 188; and for the acquisition of gw, see Macken, 1979: 36). Turning to the glottalized and aspirated stops and taking Latin as an example, we realize that t? became d, while th and dh evolved into t and / or d, respectively. In child language, voicing is acquired before glottalization (Burling, 1973: 72 and 74; and Jakobson and Waugh, 1979: 160), the unmarked stops before their aspirated counterparts, and/before dh (cf. Ingram, et al., 1980: 188, who conclude that among fricatives and affricates "/f-/ was the earliest acquired sound by far," and Srivastava, who reports that "not until 2:0 did the [Hindi] voiceless and voiced aspirates appear" (Macken, 1980: 159); (the emphases on acquired and appear are mine). The evolution of laryngeals is closely tied to the history of vowels. The loss of laryngeals led, in addition to qualitative changes in certain cases, to the compensatory lengthening of the adjacent vowels, and the primary or secondary long vowels have been steadily shedding their quantitative feature. As "the most complex sounds in a universal phonological hierarchy" (Keiler, 1970: 88), laryngeals must have been acquired very late. The Arabic pharyngealized consonants, which can serve in part as a fair approximation of the Indo-European laryngeals, are difficult to acquire, especially when not word-initial. According to Omar (1973: 55 and 56), h can still be replaced with h by children of four, five, or even six years of age, while G does not appear before four, and can remain a problem until thirteen years of age! As far as the
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vowels are concerned, the acquisition of the short ones precedes that of the corresponding long ones (cf. W. and C. Stern, [1922: 289], and also Omar [1973: 54 and 57], who observed that the last qualitative distinction was mastered at 2;3, while "long vowels were correctly distinguished and imitated at 3;0). In the light of these comparisons (for a less sketchy account, cf. Bichakjian, forthcoming), it seems safe to conclude that the inherent phonological changes proceeded in the direction of earlier-acquired sounds. In the evolution of morphology, prepositions and article came to replace declensions. The acquisition of the latter was surely a long process: it takes the Russian child "until seven or eight to sort out the proper declensional... suffixes" (Slobin, 1966: 135). But the acquisition of articles and prepositions is achieved by the beginning of the fourth year. The difference is also considerable between the acquisition of the subjunctive and that of the future tense, which can be traced back to modal variants of the Indo-European verb. The surviving subjunctives do not appear today much before halfway during the fifth year, whereas the future is mastered before the child's third birthday. The transition from ablaut to suffixation (cf. the Latin substitution of cantavi for cecini) is more difficult to assess in terms of absolute chronolgy of acquisition. Judging by the commonly observed analogical changes made by children, as in corned, bringed and foots (these examples are from J. G. and P. A. de Villiers, 1978: 85), we may conclude that, as an active process, suffixation is learned before ablaut. Of course, plural ablaut is not common in English, but past tense ablaut is, and it is probably not too risky to think that an English-speaking child hears as many strong preterites {ate, drank) as s/he hears weak ones (finished, walked). The next step in the evolution of verbal morphology is the transition from a synthetic to a compound verb form. Here the evidence may seem contradictory at first look. J. G. and P. A. de Villiers (1978: 87) write that the "use of simple past tense precedes by several years the occurrence of more complex past tenses, as in: / have been traveling[,] I have eaten, and there is evidence from Cromer (1974: 221-224) that "the delay is due not so much to the grammatical complexity of these forms as to the complexity of the ideas being expressed, since such tenses presuppose a sophisticated awareness of time and the completion of activity." This is true of English, but in German and in Dutch, for instance, where the
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synthetic and compound forms are nearly synonymous, children acquire the periphrastic form faster (W. and C. Stern, 1922: 223; and van Ginneken, 1917: 178 — 179). This relative chronology also applies to the future when the synthetic form alternates with a (nearly) synonymous analytical construction (cf. Gregoire, 1947: 121-123 and 127-128). The evolution of morphology has unquestionably gone in the direction of earlier-acquired features. The progress is considerable in the case of prepositions and articles doing the work of declensions, and also in the case of the future tense, which emerged as moods were fading away. Furthermore, children seem to prefer suffixation to ablaut, and, when synthetic and periphrastic forms of the verb are (nearly) synonymous, children become familiar sooner with the alternative where an auxiliary can be used. The last set of changes that will be examined here are those that shaped the syntax of modern languages. These are extant languages with correlative clauses, but this structure is something of an oddity today, and I find no data showing how the acquisition of correlatives would compare with that of subordinate clauses. I am inclined to think that since it presupposes the synchronization of two items (cf. Latin ubi... ibi 'where ... there,' ut ... ita 'which way ... that way,' German wer ... der 'who ... that [one]') correlation is acquired later than subordination, which 'simply' implies the tagging of an adverbial clause to the main utterance. Subordination is indeed not a very difficult part of syntax to acquire, and although we cannot really tell how long it would take a child to acquire participial phrases like those quoted above from Latin and Sanskrit, the existing evidence clearly suggests that they would be learned later than subordination (cf. Bowerman, 1979: 228). Comparing the use of word order with the mastery of case markers can be carried out with even greater certainty. We know that, already at the level of two-word utterances, the child normally puts the subject in the first position as in car bridge, meaning 'the car is under the bridge' (Braine, 1973: 418). Indeed, even in English, where inflectional affixes are few, "children learn word sequences ... before morphological contrasts (as between 'block,' singular, and 'blocks,' plural)" (Bloom, 1973: 438). It is true that in the case of agglutinative languages, where case markers are absolutely regular, and where speakers use them consistently, the accusative is acquired very early, and children learn
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to depend upon it (Slobin and Bever, 1982: 248). However, it is significant to note that when these children's intuition is tested with "ungrammatical (uninflected) sequences[,] ... NNV forms show a significant tendency for interpretation of the first noun as agent; [likewise,] uninflected NVN shows a strong trend in this direction" (Slobin and Bever, 1982: 248). It seems clear that word order plays a central role. The child will use first the SO order and gradually evolve either to SVO or SOV. Admittedly, if the adult language has an accusative marker, the child will acquire that marker and use a free order, but even then the SO order will remain fundamental, as evidenced by the interpretation given to unmarked NNV and NVN sequences. When the rise of subordination and the use of word order instead of case markers are compounded with the developments observed in morphology and phonology, it becomes clear that all the inherent changes of language have gone in the direction of earlier-acquired features. This conclusion, unlike the observation that languages tend to become analytical, can tie in with the biological data and, by so doing, perhaps enable us to provide a genetic explanation of language evolution. 3.3 The evolution of Indo-European languages: a case study We have just observed that the inherent changes that characterize the evolution of the Indo-European languages proceeded in the direction of earlier-acquired features. Before linking this observation with man's biological evolution, we would have to know whether the other languages have also evolved towards earlier-acquired features. Frankly, this is where my experience falls short, and where further research will have to be carried out. My own tentative conclusion, based on the consideration of pasing remarks made about non-Indo-European languages, is that they too moved in the direction of earlier-acquired features. The elimination of morphology, for instance, which has gone much further in the Sino-Tibetan languages than in the Indo-European family, is a telling example (for the data, cf. Jespersen, 1964: 369 — 373). The nineteenth-century linguists, August Schleicher and his followers, who ranked the isolating languages as the most primitive, the inflective languages as the most advanced, with the agglutinative languages having an intermediate position, were simply expressing their admiration for the
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classical cultures of antiquity and for the intricate languages that carried them, but they were not providing a valid parameter for the assessment of linguistic evolution (cf. also Greenberg, 1957: 60). I should also point out that languages do not push their entire sets of features in the direction of earlier-acquired items as a block of raw material fed into a machine. Language evolution is not monolithic; it displays a mosaic pattern like our biological evolution. Latin, for instance, had labiovelars and no aspirates, while classical Greek had the latter, but not the former. Armenian has eliminated gender, but still has declensions, while French has no declensions, but has gender, be it in a reduced number. Finally, it should be born in mind that a given change which, as a whole, can be characterized as proceeding in the direction of earlier-acquired features, may produce the opposite effect on some particular item. Irish degemination has led, for instance, to the creation of nonstrident fricatives, which are late-acquired sounds, though most of them were later eliminated. If these considerations are taken into account when assessing the inherent evolutionary changes of all natural languages, I believe no major contradiction will be found, and it will be observed that they generally moved in the direction of earlier-acquired features.
4. The genetic origin of language evolution The jump is obvious, and I shall make no attempt to deny it. My evidence is from Indo-European languages and, at the present time, I can only hypothesize that the direction of their evolution applies to the evolution of all human languages. Further research will hopefully confirm my generalization, which must not be interpreted as an exercise in ethnocentricity, but a call for a broader approach to the problem. Let me be optimistic and for the remainder of this paper assume that further research will confirm my hypothesis. In that case, the pedomorphic course of language evolution becomes a development that parallels our biological evolution. Furthermore, since our biological evolution is interpreted as being essentially the result of the retardatory action produced by our regulatory system on our structural genes, and since there are good reasons to assume that
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speech has genetic correlates, it is logical to conclude that language evolution is also the result of the retardatory action produced by our genes. Gould (1977: 376) does not comment on speech, but he does point out that "human retardation is a pervasive phenomenon of almost all systems, somatic and germinal," and he adds: "general retardation of this sort entails extensive pedomorphosis as an almost ineluctable consequence." No doubt, the genetic evidence for language is circumstantial, and the linguistic data are not exhaustive, but as Lenneberg (1967: 240) reflects, "although we can only speculate on this point, our speculations with regard to language are no more daring than with regard to most other structural or functional features." Therefore, I shall 'speculatively' conclude that language evolution is a pedomorphic process brought about by the retardatory action of our regulatory genes.
5. A putative explanation The riddle of language evolution has been solved, but putatively. I have assumed that man's biological evolution is essentially the result of a change in the regulation of gene expression; I have also assumed, along with Lenneberg (1967), that language has genetic correlates. Furthermore, we have observed that the Indo-European languages have evolved towards earlier-acquired features. Hypothesizing that this direction is common to all natural languages, I have concluded that language evolution should be traced back to the retardatory action of our regulatory genes. I have not proven that language evolution has a genetic source. For that, further linguistic research and greater molecular knowledge are necessary; but already the historical linguist can use the theory of linguistic pedomorphosis to explain language evolution, be it putatively.
Notes 1. Editor's remark: The actual German proverb is, of course, Wer einmal lügt dem glaubt man nicht, und wenn er auch die Wahrheit spricht. Bichakjian's comment (pers. comm. 12.12.1985): "My version of the German aphorism is taken from Fourquet, the well-known French specialist of the German language, and as such it suits my argument very well. Your version, perhaps the right one, has an added element, which is not necessary for the point I am making, and which may even confuse the issue."
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References Aitzemüller, Rudolf 1978 Altbulgarische Grammatik als Einführung in die Slavische Sprachwissenschaft. Freiburg in Br.: Weiher. Bichakjian, Bernard H. 1982 La genese de la subordination de l'indo-europeen au frangais. In Q. I. M. Mok, I. Spiele and P. E. R. Verhuyck (eds.) Melanges de Linguistique, de Litterature et de Philologie Medievales Offerts ä J. R. Smeets. 5 — 20. Leiden: Instituut Frans. (forthc.) Paedomorphosis and Language Evolution. Bloom, Lois 1973 Why not Pivot Grammar? In Charles Α. Ferguson and Dan I. Slobin (eds.), Studies of Child Language Development. 430—440. New York: Holt, Rinehart and Winston. Bowerman, Melissa 1979 The acquisition of complex sentences. In Paul Fletcher and Michael Garman (eds.), Language Acquisition: Studies in First Language Development. 285 — 305. Cambridge: The University Press. Braine, Martin D. S. 1973 The ontogeny of English phrase structure: The first phase. In Charles A. Ferguson and Dan I. Slobin (eds.), Studies of Child Language Development. 407—421. New York: Holt, Rinehart and Winston. Burling, Robbins 1973 Language development of a Garo and English-speaking child. In Charles A. Ferguson and Dan I. Slobin (eds.), Studies of Child Language Development. 69—90. New York: Holt, Rinehart and Winston. Chatteiji, Suniti Kumar 1970 The Origin and Development of the Bengali Language. 2 Vols. London: Allen and Unwin. Collart, Jean 1975 Grammaire du Latin. 3rd Ed. Paris, PUF. 1980 Histoire de la Langue Latine. 3rd Ed. Paris: PUF. Cromer, R. F. 1974 The development of language and cognition: The cognition hypothesis. In B. Foss (ed.), New Perspectives in Child Development. 221 — 224. Harmondsworth, Middlesex: Penguin Books. Gamkrelidze, Thomas V. and V. Ivanov 1973 Sprachtypologie und die Rekonstruktion der gemeinindogermanischen Verschlüsse. Phonetica 27. 150-156. Ginneken, Jacques van 1917 De Roman van een Kleuter. Nijmegen: Malmberg. Gould, Stephen J. 1977 Ontogeny and Phylogeny. Cambridge, MA: The Belknap Press of Harvard University Press. Gould, Stephen J. 1980a Is a new and general theory of evolution emerging? Paleobiology 6. 119-130.
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The Panda's Thumb. More Reflections in Natural History. New York: Norton. Greenberg, Joseph H. 1957 Essays in Linguistics. Chicago: The University of Chicago Press. Gregoire, Antoine 1937—1947 L'apprentissage du Langage. 2 Vols. Bibliotheque de la Faculte de Philosophie et Lettres de l'Universite de Liege, Fase. CVI, and Paris: Droz. Henig, Robin Marantz 1982 The evolution revolution. Sciquest, January. 16—21. Ingram, David, Lynda Christensen, Sharon Veach and Brendan Webster 1980 The acquisition of word-initial fricatives and affricates in English by children between 2 and 6 years. In Grace H. Yeni-Komshian, James F. Kavanaugh and Charles A. Ferguson (eds.), Child Phonology. Vol. I. Production. 169—192. New York: Academic Press. Jakobson, Roman and Linda R. Waugh 1979 The Sound Shape of Language. Brighton, Sussex: The Harvester Press. Jespersen, Otto 1964 Language, its Nature, Development and Origin. New York: Norton. Keiler, Alan R. 1970 A Phonological Study of Indo-European Laryngeals. The Hague: Mouton. Kortlandt, Frederik 1978 Proto-Indo-European obstruents. Indogermanische Forschungen 83. 107-118. Labov, William 1972 Sociolinguistic Patterns. Philadelphia: The University of Pennsylvania Press. Lass, Roger 1980 On Explaining Language Change. Cambridge: The University Press. Lenneberg, Eric H. 1967 Biological Foundations of Language. With appendices by Noam Chomsky and Otto Marx. New York: Wiley. Macken, Marlys A. 1979 Developmental reorganization of phonology: A hierarchy of basic units of acquisition. Lingua 49. 11—49. 1980 Aspects of the acquisition of stop systems: A cross-linguistic perspective. In Grace H. Yeni-Komshian, James F. Kavanaugh and Charles A. Ferguson (eds.), Child Phonology. Vol. I. Production. 143 — 165. New York: Academic Press. Malmberg, Bertil 1955 The phonetic basis for syllable division. Studia Linguistica 9. 80 — 87. Meillet, Antoine 1926 Caracteres Gineraux des Langues Germaniques. 3rd Ed. Paris: Hachette. 1964 Introduction a I'Etude Comparative des Langues Indo-Europeennes. University of Alabama: University of Alabama Press.
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Convergences des developpements linguistiques. In (Author) Linguistique Historique et Linguistique Generale 61—75. Paris: Champion. Montgomery, Thomas 1977 Dialectal Spanish päsenos 'pasemos,' analytic drift, and French -ons. Romance Philology 30. 609-615. Mosse, Fernand 1942 Manuel de la Langue Gothique. Grammaire, Textes, Glossaires. Paris: Abier. Omar, Margaret 1973 The Acquisition of Egyptian Arabic as a Native Language. The Hague: Mouton. Parker, Sue Taylor and Kathleen R. Gibson 1979 A developmental model for the evolution of language and intelligence in early hominids. The Behavioral and Brain Sciences 2. 367—408. Sapir, Edward 1949 Language: An Introduction to the Study of Speech. New York: Harcourt, Brace and World. Slobin, Dan I. 1966 The acquisition of Russian as a native language. In Frank Smith and George A. Miller (eds.), The Genesis of Language: A Psycholinguistic Approach. 129-148. Cambridge, MA: The MIT Press. Slobin, Dan I. and Thomas G. Bever 1982 Children's use of sentence schemas: A crosslinguistic study of word order and inflections. Cognition 12. 229 — 265. Stern, William and Clara Stern 1922 Die Kindersprache. Eine Psychologische und Sprachtheoretische Untersuchung. 3rd Ed. Leipzig, Barth. Villiers, Jill G. de and Peter A. de Villiers 1978 Language Acquisition. Cambridge, ΜΑ: Harvard University Press. Winter, Werner (ed.) (1965) Evidence for Laryngeals. The Hague: Mouton. Winter, Werner 1978 The distribution of short and long vowels in stems of the type Lith. esti : vesti : mesti and OCS jasti : vesti : mesti in Baltic and Slavic languages. In Jacek Fisiak (ed.), Recent Developments in Historical Phonology. Papers prepared for the International Conference on Historical Phonology held at Ustonie, Poland, March 17-20, 1976. Pp. 431 —446. The Hague: Mouton.
Language evolution and pedomorphosis Jan Wind
Abstract A critical discussion is given of the possible contribution by the pedomorphosis concept to solving the question of language origins. Particular attention is paid to Bichakjian 's approach (in this volume). From the viewpoint of evolutionary biology, molecular biology, and epistemology, it would seem that for the time being the use of the pedomorphosis concept is in this respect rather limited. An attempt is made to explain the attractiveness of concepts like pedomorphosis for explaining phenomena at a different etiological level.
1. Introduction How did present-day languages come into being? Although, as all participants of this conference are well aware, this question has fascinated many scientists for a long time, attempts to solve it by using the pedomorphosis concept have been, so far, rare as well as peripheral in the discussions. (The term pedomorphosis denotes the occurrence in adult organisms of morphological features which were present only in non-adults in the ancestral species). Therefore, Bichakjian (this volume) is to be congratulated for his new, refreshing approach in which he ably combines data from modern biology with those from linguistics. However, such synthesizing of data from two diverse and broad fields increases, of course, the risk of one's not discovering pitfalls as readily as when one remains in one's own realm. As I am linguistically quite naive, my contribution will necessarily be limited to an attempt at pinpointing and describing some of the possible pitfalls, especially those that lurk in the biological field; and it is meant to refine Bichakjian's approach rather than to depreciate it. Readily assuming that the
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data from historical and comparative linguistics have been correctly rendered by Bichakjian, I will rather consider critically the following concepts: that of pedomorphosis; that of structural versus regulatory genes; the alleged links between genes and language; and the way all these would seem to interlock as interpreted from the point of view of modern biology.
2. Pedomorphosis The concept of pedomorphosis (and the largely overlapping one of neoteny) has for many years been a hotly debated issue among biologists. Consequently, in biology it does not generally have the scientific status ascribed to it by some nonbiologists. It is based on a rather hypothetical, and typological-phenomenological interpretation, itself based on pattern-recognition in macromorphological studies, aimed at discovering "Baupläne." This has resulted in lumping together some comparative zoological, morphological data. Hence, the concept is not based on an empiricist, (molecular-)biological approach; and its value, therefore, seems to be mainly heuristic. In that quality it is chiefly limited to usage in purely biological considerations. Bichakjian rightly quotes Gould (1977), who wrote an impressive volume on phylogeny and ontogeny (i. e. the evolutionary and the individual development), mainly focusing on the historical epistemology of their interrelationships. A central theme of his book was, in fact, pedomorphosis. And already some sixty years ago my compatriot, the anatomist Bolk (1926) postulated that pedomorphosis played an important role in human origins and evolution. However, despite the impressive progress of modern biology, the concept remains at a descriptive level. And even there, its existence remains questionable (de Beer, 1962; Wind, 1970). Hence, care should be taken not to have the concept removed prematurely from the hands of theoretical and morphological biologists. I think that the concept would only acquire a more respectable — or at least a more useful — status once biologists could demonstrate that underlying a pedomorphic evolutionary trend or a species' pedomorphic appearance there was an etiologically deeper driving force. The latter, then, would most likely be found in an enzyme. Bolk
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(1926) rightly reasoned along similar lines by hypothesizing a pedomorphic hormone. Such a substance, then, should be able to inhibit tissues during ontogeny from developing along the lines of the adult ancestral morphology. Until biologists are able to prove the existence and operation of one enzyme, or a few concerted enzymes which I — avant la lettre — would call 'retardase' or 'neotenase', one should handle the concept with the utmost restriction. This applies a fortiori to extrapolating from the typological, morphological level by stretching the concept to its application in physiology and, subsequently, in behavior, whence an abstraction of the latter, like language (see 4).
3. Genes Roughly the same type of considerations applies to the concepts of structural versus regulatory genes. Their scientific status outside molecular biology would seem to run somewhat ahead of the one within that discipline. Basically, the terms have primarily been coined to form a heuristic, although hypothetical, device assisting in explaining certain evolutionary-morphological, not so much molecular-biological, phenomena. To be sure, an empiricist approach of this hypothesis is much more feasible than the case of pedomorphosis. Hundreds of different DNA sequences have been described as found in various species, most of which sequences code for one specific protein, and each of which is able to reproduce itself. However, within one organism there are thousands of different DNA sequences. Even more embarrassingly, their interrelationships — mainly as effected by their protein end-products — appear to form an extremely complicated network of mutual interactions, even in so-called simple organisms like bacteria. Hence, their unraveling will occupy many future generations of scientists (Wind, 1985a). Right now, however, it would seem that the distinction between the alleged two types of genes is rather artificial, and that many genes can, in fact, bear both labels at a time. As with pedomorphosis, an attractive term has somewhat prematurely been taken off the hands of its inventors.
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4. Levels of causation What are the links between genes and languages? From the preceding section it is clear that they are epistemologically very long as well as stochastic and, moreover, unfortunately, largely unknown. This applies a fortiori to genes and language differences which are at the focus of speculations on language origins and evolution. A somewhat vague, e. g. Chomskyan, statement like 'language has a genetic basis' may well be of interest to those not fully familiar with the genes' action (like probably some nonbiologists); but to biologists the statement sounds somewhat trivial. For, first, genes lie at the basis of all phenomena of living organisms; and, second, the links, at least the relevant ones, are unknown and, even worse, are unlikely to become fully known. I wonder whether Bichakjian might not have fallen victim to a methodological malentendu which is, in fact, rather common in theoretical biological constructs. It consists of mixing different levels of causality. My point can probably best be illustrated by a schema (Fig. 1). This was originally devised for a slightly different purpose but may serve here equally well. And I think that we should invoke systems theory to further analyze the underlying methodological problem. In a scientific approach, the behavior of Homo sapiens sapiens, including the one called language, is seen as the result of the interaction of the environment and the genes. The latter, however, does not directly act upon the brain — generating and processing language — and the muscles expressing it, but rather via a number of intermediate processes. And underlying the genes' action we find the basic properties of replicators (and even more basic physical processes which, in the remote past, have caused the replicators, i. e. the DNAs, to originate). Insufficient recognition of the nature of this hierarchy may be responsible for some common misunderstandings at the interface of biology and the humanities.
5. A role of language evolution in language evolution? The above methodologically questionable 'level mixing' is not uncommon. As far as the sociobiological and biopolitical literature is
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concerned, I have given a number of instances as shown by nonbiologists and biologists alike (Wind, 1985a, b). But how can we account for this common occurrence? I think it is, strangely enough, mainly theories of linguistics and language evolution which provide an explanation. Language must, during the greater part of mankind's existence, mainly or solely have been used to describe phenomena at Fig. l's upper levels, i. e. those pertaining to daily life. It is only relatively recently that some of our species' members, first called philosophers, later also scientists, came to occupy themselves with the schema's lower levels. In so doing they carried with them the upper levels' jargon using it to describe phenomena at the lower levels. Hence "celestial bodies like twin stars pull at each other's field of gravity;" "in the Northern hemisphere the sun in June normally climbs higher on account of the globe's axis not possessing a perpendicular stance;" "hydrogen reacts with chloride to generate an aggressive substance;" "the selfish genes reproduce and compete;" "animals display certain strategies like altruism." Etymologically experienced linguists may undoubtedly come up with more pertinent examples. However, mine probably suffice to show that the sciences' jargon abounds with terms originally designed for usage at the upper levels. Consequently, most of them carry a heavy anthropomorphic load (exceptions may be provided by neologisms in nuclear physics; or would they just be examples harder to crack?). Admittedly, in many cases the earlier meaning of the terms and their components is — even by linguists — not readily perceived. However, in some they are, and these terms are often going to live their own life. 'Evolution' provides an illustrating example, though here the confusion arises not so much from the original ex and volvere, but rather from its Darwinian connotation. Sinners mixing the various language levels often ascribe — just by transplanting the term — Darwinian rules and laws to nonbiological systems, e. g. to social sciences' ones, where completely different rules and laws apply. Probably, the frequency with which terms are (mis)used in this way, depends on their popularity and scientific status as well as on their seemingly explanatory power. And I wondered, therefore, whether the term "pedomorphosis" would not also be a likely candidate to be used in the above way.
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6. Conclusion It would seem that two epistemological processes are interfering with Bichakjian's proposal. The first one, probably rather common, consists of the tendency of scholars — both from the social sciences and the humanities — to cuddle and advertise their findings so enthusiastically that they push their speculations to, and sometimes even beyond, the limits of their scientific acceptability. Although the scholars themselves may well be aware of this stretching of their speculations' credibility, outsiders more rarely are, and so are more likely to ascribe a scientific status to the underlying concepts, which is higher than the one that was, on logical grounds, originally ascribed to them by the specialists well-acquainted with them. The second one, probably somewhat less common, is the difficulty of handling the relationship between various levels of explanation. In the present case, we have the hierarchical levels of molecular biology, biochemistry, genetics, morphology, physiology, ethology, social and humanistic sciences, and linguistics. The concept of pedomorphosis belongs to that of morphology, and utmost care should be taken when using it at other levels. Of course, analyzing such handling is meat and drink to philosophers, especially to those working on reductionism and systems theory, and it is beyond my grasp. I have some feeling, however, that using the pedomorphosis concept not only at the morphological level, but also at the molecular-biological and at the same time at the linguistic level may turn out to be a weak spot in Bichakjian's otherwise laudable and thoughtful approach. Legends to the illustration A provisional attempt to represent schematically a causal analysis of a certain category of behavior of a certain human individual as compared to the same category of behavior in an individual of another species. Various sciences are operant at the various levels of causality. A clear distinction of their variety may assist in solving some of the methodological issues raised by applying biological concepts outside biology, including the pedomorphosis concept in linguistics. See further the text. (From Wind, 1985a).
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References Beer, G. de 1962 Embryos and Ancestors. Oxford: Clarendon. Bichakjian, Β . H . 1986 Neoteny and language evolution. (In this volume). Bolk, L. 1926 Das Problem der Menschwerdung. Jena: Fischer. Gould, S. J Ontogeny and Phylogeny. Cambridge, MA: Harvard University Press. 1977 Wind, J. 1970 On the Phylogeny and the Ontogeny of the Human Larynx. Groningen: Wolters-Noordhoff. 1985a Sociobiology and the human sciences. An introduction. In Jan Wind (ed.), Essays in Human Sociobiology. 3 — 24. London: Academic Press. Review of: Politik und Biologie, by Η. Flohr and W. Toennismann 19856 (eds.), Politics and the Life Sciences 3. 207 — 211.
Language evolution and pedomorphosis A reply to Jan Wind Bernard H. Bichakjian
Wind's paper (in this volume) is conceived as a kind but critical attempt to set the biological record straight, implying thereby that the biological support of my theory of language evolution would be hard put when made to stand a biologist's test. Let me briefly discuss his three arguments. 1. "... the concept [of pedomorphosis] ... remains at a descriptive level ... [and un]til biologists are able to prove the existence and operation of one enzyme or a few concerted enzymes ... one should handle the concept with [the] utmost restriction." (P. 138 — 139). 1.1 That pedomorphosis is still at the descriptive level cannot be denied, of course— and I have made it a point to stress the state of the art — but so is the commonly accepted Synthetic Theory (cf. Dobzhansky, who pointed out that there is no "known natural process tending towards producing nucleotide changes at specific sites in specific genes" [Dobzhansky et al., 1977: 64; and also Gould, 1980: 180 — 193]). Scientists cannot produce a human baby out of a fertilized chimpanzee ovum, nor a seal out of a dog, nor a bird out of a reptile, but no evolutionist will seriously dispute that man, seal, and bird had, respectively, an apelike, doglike and snakelike ancestor. Like all species-producing mutations, pedomorphosis cannot be induced, but the descriptive data suggest that such a process has taken place. It is logically inferred that this was the result of a change in the regulation of gene expression. This is indeed an inference, and our understanding of pedomorphosis remains putative. But we must be careful: if we reject pedomorphosis because of its descriptive status, the idea of evolution, in general, and the Synthetic Theory, in particular, will have to be rejected for the same reason; yet no scientist wishes to entertain such thoughts.
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1.2 Now, about the need to "handle the concept with [the] utmost restriction.'''' Let me state, first of all, what I have done. Macroevolutionists had observed that man had steadily eliminated some of his ancestor's late-acquired biological features and replaced them with early-acquired ones. They have called this process "pedomorphosis" or "neoteny" — descriptive terms, indeed — and ascribed it to a change in the regulation of structural genes. Using the Indo-European languages as a case study, I examined the linguistic data and observed that over the last four or five millennia the languages of this family have also repeatedly replaced late-acquired features and strategies with earlier-acquired ones. In a very brief survey, another linguist has made a similar observation concerning the evolution of an American Indian language. Since, moreover, a considerable amount of data suggests that man's ability to acquire and use articulated speech has biological correlates, I came to the conclusion that language evolution is also a pedomorphic process, and I ascribed it to the action of the regulatory genes on the cellular material coding for human speech. By so doing, have I failed to "handle ... [pedomorphosis] with [the] utmost restriction"? Gould, for one, does not seem to think so. In a recent letter to me, he wrote: "I had not thought of applying pedomorphosis to the history of linguistic development, but the idea makes sense to me" (Gould, 1986, pers. comm.).
2. "... the distinction between the alleged ... [structural and regulatory] genes is rather artificial, and many genes can in fact bear both labels at the time." (P. 139). 2.1 The existence of genes that can be both structural and regulatory is a well-known fact, but the dual nature of such genes confirms, rather than invalidates, the importance of gene regulation. Whatever the distribution of structural and regulatory elements, each specific protein has to be coded for and its synthesis regulated, i. e. induced, sustained and repressed. Therefore, the terms structural and regulatory genes may be more convenient than descriptively accurate but they do not distort the presentation of either ontogenetic or phylogenetic processes.
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3. "... using the pedomorphosis concept not only at the morphological level, but also at the molecular-biological and at the same time at the linguistic level may turn out to be a weak spot in Bichakjian's ... approach." (P. 143). 3.1 First of all, the use of pedomorphosis at the molecular-biological level is not mine. It is common practice in evolutionary biology. Since evolutionary changes occur at the cellular level, the explanation of pedomorphosis, like that of any other type of speciation, has to be sought at the molecular level. It is no secret that the gap between micro- and macro-evolution is far from being closed, but that is an empirical matter, not an epistemological problem. 3.2 Using the concept of pedomorphosis in linguistics is indeed an initiative of mine (cf. 1.2), and it is crucial for the theory of language evolution I propose. As I mentioned above, at least Gould seems to think that "the idea makes sense," but let us examine Wind's objection. The objection is articulated in two parts. First, Wind postulates the existence of a hierarchical system which would have the following sequence: "
8. 7. 6. 5. 4. 3. 2. 1.
linguistics social and humanistic sciences ethology physiology morphology genetics biochemistry molecular biology
He then concludes that "insufficient recognition of this hierarchy's nature may be responsible for some common misunderstandings at the interface of biology and the humanities(P. 140). Except for the order in which linguistics is made to appear, this hierarchy may very well be valid, and I shall not dispute it. But I do wish to discuss the place given to linguistics. To make my point, let me start with a more obvious case. Human hair may be utilized to convey sexual distinctions, virility, social attitudes, racial or national ties, religious affiliations or functions, one's concern for
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elegance and, inadvertently, one's dubious taste. All these considerations belong no doubt to Wind's tiers 6 and 7, but hair itself is a morphological feature, which along with all its characteristics is coded for at the cellular level, and whose growth and fall are also genetically determined. Now, speech also serves to convey the considerations belonging to tiers 6 and 7, and no doubt with greater accuracy, but with its peripheral organs and cortical centers it is also a function, and as such cannot be excluded from tiers 4 and 5. Since it is commonly accepted that language acquisition is coded for and regulated genetically — I have no space to review the evidence, which admittedly is circumstantial, but cf. 1.1 — the interface between biology and speech, and hence language evolution, cannot be considered the result of a misunderstanding. The misunderstanding has been rather on the part of those who, having stressed so much the social, artistic and intellectual aspect of language, have lost track of its biological correlates. Language evolution — and I have stressed that the theory of linguistic pedomorphosis applies to the material aspect of language — language acquisition, and the biological correlates of the latter are, I believe, directly related, and for that reason my approach should "make sense." Having refuted, I hope, Wind's methodological and empirical objections, I should like to emphasize in closing that my explanation of language evolution has never been motivated by a desire to coat empty words with the spurious credibility of a scientific veneer. Whether the present state of technology enables the molecular biologist to isolate them or not, the biological correlates of speech are real and, consequently, the key to language evolution lies buried in the labyrinth of man's DNA sequences. References Dobzhansky, Theodosius, Francisco J. Ayala, G. Ledyard Stebbing and James W. Valentine 1977 Evolution. San Francisco: Freeman. Gould, Stephen J. 1980 The Panda's Thumb. More Reflections in Natural History. New York: Norton. 1986 Personal communication. Wind,Jan 1986 Language evolution and pedomorphosis. (In this volume).
Brain size and the evolution of language Kathleen R. Gibson
Abstract One of the most striking features of the human species is its incredibly large brain size which, at an average weight of 1250 to 1300 grams, is about three times the size of the average ape brain. Most of this massive brain size differential reflects the greatly enlarged human neocortex. The contributions of neocortical enlargement to the linguistic endeavor are, however, poorly understood. Based on behavioral and neurological data, this paper suggests that an enlarged neocortex has provided for quantitatively increased differentiational and constructional capacities in a variety of sensory and motor domains, and provides a common underpinning for both tool-use and language. Increasing brain size and tool complexity in the archeological record provide concrete evidence for increases in mental constructional capacity. This evidence is used to formulate a tentative model of the evolution of language.
Introduction The concept that man is superior to and qualitatively different from the animals has long pervaded Western culture. On the one hand, it is a basic tenet of Christianity that man has a soul; animals do not. On the other hand, behavioral scientists have long posited qualitative distinctions between human and animal behavior. As recently as the early 1960s, for instance, man was still considered to be the only animal that makes tools, and the only one possessing such language-related capacities as symbolization, environmental reference, learned vocalizations, self-recognition and the ability to make cross-modal associations (Buettner-Janusch, 1966; Gesch-
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wind, 1965; Lancaster, 1968; Myers, 1976; Oakley, 1959; White, 1959). In recent decades, however, man's uniqueness has been challenged by the apes. Wild chimpanzees have been found to make tools for use in their feeding endeavors, while captive chimpanzees, gorillas and orangutans are purported to be capable of using the American Sign Language of the Deaf (Fouts, 1973; Gardner and Gardner, 1969, 1980; Jones and Sabater Pi, 1969; McGrew, 1974; McGrew and Rodgers, 1983; Miles, 1982; Nishida and Hiraiwa, 1982; Nishida and Uehara, 1980; Patterson, 1978; Patterson and Linden, 1981; Van Lawick-Goodall, 1968, 1970). Moreover, it is now known that a variety of apes and monkeys are capable of cross-modal associations, environmental reference, learned vocalizations and self-recognition (Davenport and Rogers, 1970; Davenport, et al., 1973; Gallup, 1979; Menzel, 1973; Seyfarth and Cheney, 1982; Steklis and Raleigh, 1979; Sutton, 1979). The scientific reaction to this news has been neither to accept the chimpanzee into our species nor to abandon our concepts of human uniqueness. Instead, we have constantly redefined humanity. Whereas man was once the only animal who could symbolize, he is now the only one who can construct a sentence (Terrace, 1979, 1980). Whereas once he was the only animal who could make a tool, he became, first, the only one who could use a tool to make a tool (Wright, 1972) and, later, the only one who could use a tool to make a tool that could then be used to make a tool. Few, however, have stopped to ask whether this continual redefinition of humanity is really an appropriate scientific endeavor. Given our new understandings of ape abilities, on what scientific grounds do we even base our faith that absolute qualitative behavioral dichotomies separate man and animal? Certainly, we can not base this faith on the evidence of the brain. For the history of comparative neurology resembles that of animal behavior in this regard. Neurological structures and areas once considered unique to the human brain (and therefore capable of accounting for uniquely human behaviors) are now known to occur in rudimentary form in other animals, e. g. Broca's area, the inferior parietal association area (Von Bonin and Bailey, 1947; Galaburda and Pandya, 1982; Krieg, 1954). Hence, these areas may be quantitatively expanded in man, but they are not new. Similarly, the emergence of certain gyri or sulci and/or their repositioning in the human
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brain, once thought to reflect qualitative distinctions between man and animal, are now known to result from quantitative changes in the amount of underlying cortical tissue (Jerison, 1982). Even cerebral lateralization, long considered a hallmark of humanity, occurs in other primates (Dewson and Burlingame, 1975; Falk, 1978; LeMay, et al., 1982). Consequently, at present, the only unquestioned differences between the brains of apes and man appear to be of a quantitative nature. These quantitative differences, however, are major. For instance, the human brain, at an average weight of 1300 grams, is more than three times the weight of the average ape brain (Jerison, 1973; Tobias, 1971). In addition, major changes have occurred in the quantitative proportions of specific neural regions and structures (Holloway, 1968, 1979; Passingham, 1973, 1975). In particular, the neocortex, the neocortical association areas and certain thalamic and limbic nuclei are proportionately much larger in man than in other primates (Armstrong, 1982). Perhaps, most importantly, increased cortical size correlates with and reflects increased numbers of glial cells and increased neuronal interconnectivity (Hofman, 1983; Jerison, 1979). These data imply that language and other seemingly unique human behaviors may not be qualitatively new functions at all, but rather quantitative increases of functional capacities already present in the apes. At the very least, the data mandate a search for the meaning of brain size. For even if some future researcher should delineate an as yet unknown qualitative distinction between the brains of humans and apes, a complete understanding of human language will demand an understanding of the contribution of the massive change in brain, particularly cortical, mass to the language endeavor.
Increased cortical size: Implications for the evolution of language Although the cortex can be divided into areas based on specific sensory, motor or 'associational' functions, from a structural standpoint, all areas of the neocortex, irrespective of their presumed function, share profound similarities (Pucetti and Dykes, 1978). All
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are layered; all are composed of columnar units of nerve cell bodies, and all share certain broad patterns of fiber connectivity. Consequently, it has been suggested that all neocortical areas, whatever their ostensible function, share similar neuronal processing mechanisms (Gibson, 1978; Mountcastle, 1978). If so, then unraveling the functions of any cortical area may shed light on the processing mechanisms utilized by others, including those specifically involved in the language endeavor. Clues to these general processing mechanisms can be gained from examining the works of both neurobiologists and cognitive psychologists. Particularly helpful in this regard are the works of the Swiss psychologist Jean Piaget and his followers (Piaget, 1952, 1954, 1955). These works trace the maturation of intelligence from infancy to adolescence and suggest that two interacting processes underlie the development and expression of a wide variety of sensorimotor and cognitive skills including sensory perceptions, eye-hand coordinations, object concepts, tool use, language, the understanding of causality, logic and mathematical ability, morality and memory. These processes are differentiation and construction. By differentiation is meant the ability to break sensory perceptions, motor actions or cognitive concepts into fine component parts (e. g. break a word into individual phonemic components). By construction is meant the reassembly of these differentiated components into new complex perceptual, motor or conceptual wholes (e. g. putting phonemes together in a variety of patterns to make a variety of words). Construction in the Piagetian framework is quantitative as it involves holding a number of different concepts in mind simultaneously and assembling them into new holistic patterns. It is hierarchical in the sense that individual sensory, motor or conceptual constructions may themselves be used as subcomponents of new constructions, during which time they must be subordinated to an overall constructional plan (e. g. incorporation of words into sentences or paragraphs). It is also flexible and varied allowing the construction of a nearly infinite variety of motor actions, sensory perceptions or abstract concepts. Neurological data suggest that these differentiational and hierarchical constructional skills are built into the fundamental plan of the neocortex. Contained within the neocortox, for instance, are 'primary' and 'secondary' sensorimotor areas devoted solely to
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within-modality data analysis (e. g. auditory, visual, tactile, or motor) and association areas devoted to multimodal analysis and synthesis. Anatomically, primary areas interconnect with the brainstem and with secondary areas of the same modality, but not with each other. Secondary areas interconnect with the association areas and these, in turn, interconnect with each other (Crosby, et al., 1962; Pandya and Kuypers, 1969). The resulting anatomical connectivity pattern is, thus, admirably designed to permit fine grained analysis and construction within individual sensorimotor modalities, and hierarchical incorporation of within-modality analyses into cross-modal constructions. Physiological and clinical data support this interpretation. The primary sensory and motor areas perceive finely analyzed sensorimotor components rather than holistic shapes or actions; e. g. angles, line orientations, tones, pressure points (Mountcastle, 1978). Holistic images can be perceived, or organized action patterns elicited, only by taking these differentiated sensorimotor elements and combining them into new constructed forms. Evidence suggests that, at least in part, this construction of within-modality object images occurs primarily within the secondary areas (Duffy and Buschfiel, 1971; Gross, et al., 1972; Luria, 1966; Mountcastle, 1978). The association areas, in turn, have long been known to engage in higher cross-modal synthetic tasks of both a sequential and a simultaneous nature. These areas are particularly important in permitting the construction of object names, object manipulation tasks, and grammatical, mathematical, and artistic forms (J. W. Brown, 1972; Geschwind, 1965; Luria, 1966). Two questions emerge from this analysis. Given that cortical organization appears admirably designed to provide differentiational and hierarchical constructional capacities, does increased cortical size provide for increased levels of these capacities? If so, can quantitative differences in these capacities account for the major behavioral differences between man and ape? The keys to these questions lie with Jerison's findings that cortical size reflects neuronal interconnectivity (Jerison, 1979). For mathematical analysis indicates that increased differentiation and construction are predictable results of increased interconnectivity (Gibson, 1984). Perhaps, the clearest example of the potential effects of increased interconnectivity on perceptual differentiation can be gained by
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comparing two hypothetical models of color perception. At one extreme, color perception could be provided by a fixed number of neurons, each of which functions as a feature detector to perceive a specific hue, and none of which is connected with the others. In this system, the number of colors which could be perceived would correspond to the number of neurons. The more neurons, the greater the color differentiating skill. The perception of a nearly infinite variety of hues would require a nearly infinite number of neurons. At another extreme, each color feature detector could be interconnected with each of the others in such a manner that the firing of any one neuron or any combination of neurons would yield the perception of a different hue. By simple algebra, the numbers of combinations and hence of readily differentiated colors in such a system will equal 2n ~ 1 (n = number of neurons). Hence, five interconnected neurons would permit the perception of thirty-one colors; ten of 1023, and twenty of 1,048,575. It should be readily apparent that if the goal is to achieve the capacity for virtually infinite degrees of perceptual differentiation, a highly interconnected neuronal system would provide the most efficient route. Similar analyses could be applied to other perceptual and motor systems, such as pattern vision, phonemic perception, or the ability to make finely differentiated movements of anatomical organs such as the fingers, lips or tongue. The effects of discrete versus interconnected systems on motor and sensory combinatorial and constructional tasks are equally as great as those on differentiational skills. With respect to sound production, for instance, two extreme models can be envisioned. In one a discrete number of unconnected neurons would each code for a specific combined action of tongue, lips, palate and larynx. This system would yield the ability to produce as many phonetic sounds as there are neurons. In the other, a number of highly interconnected neurons would code for a series of graduated movements of each individual organ in such a manner that any one neuron functioning alone or any specific combination of neurons firing together would produce a different position of the organ in question. The results of each organ-specific neuronal pool could then be combined with those of the others to produce combinatory movements. The latter model produces by far the most versatility. For example, ten neurons each coding for ten combined positions of oral cavity would lead to the ability to produce ten phonetic sounds. By
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contrast, ten interconnected neurons, any one or more of which firing in combination would produce a different position of the tongue, could provide for the ability to produce 1023 graduated movements of this organ alone. If similar neuronal pools separately controlled the positions of the larynx, palate and lips, then 1023 χ 1023 χ 1023 χ 1023 separate phonetic positions of the oral cavity could be produced. A highly interconnected system perhaps reaches its greatest potential with respect to the construction of action sequences such as tool-using sequences, phonemic strings, sentences, etc. Imagine, for instance, a system capable of producing five discrete phonetic sounds. If these had no interconnections of any sort, then each could be produced in isolation, but not in combination with any of the others. If the connections were of a limited, but stereotyped form, then only a limited number of combinatory sounds could be produced. For instance, five phonetic sounds symbolized by the letters a, b, c, d, e and connected as follows would yield two potential phonetic sequences: a b -*• c; d -> e. By contrast, a similar system of five phonetic sounds each interconnected with each of the others through many excitatory and inhibitory pathways would permit any combination of sounds to be uttered in any sequence of any length. Such a system would permit the beginnings of a true phonetic language. Identical analyses could be applied to systems of word, sentences, etc. In each case it is clear that a highly interconnected system provides the most language-like versatility.
Behavioral implications of the brain-size interconnectivity model Perhaps, then, attempts to find absolute qualitative distinctions between humans and other primates are superfluous. Rather, the production of seemingly unique human behaviors may lie in the superposition of brain-size mediated differentiational and hierarchical constructional skills upon behaviors already present in rudimentary form in other primates. All primates, for instance, possess a five-fingered hand, capable of grasping. The small-brained prosimeans, however, possess only
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one stereotyped grasp. This is a single-handed action involving simultaneous, coordinated movements of each of the fingers. Neither the movement of individual fingers in isolation, nor coordinated movements of the two hands are possible (Bishop, 1962). To produce a skilled manipulative organ from this rudimentary base requires precisely differentiated movements of individual fingers and the ability to coordinate diverse movements into varied grasping patterns. These are exactly the skills which increased cortical size would be expected to provide and which, in fact, the cortex does provide in man and other higher primates (Kuypers, 1962). Although, to a certain extent, these size-related skills are already present among the larger brained apes and monkeys, no primate possesses the precision of finger movement and the range of coordinated movements of the digits and hands possessed by humans (Napier, 1961; Reynolds, 1980, 1981, 1982). Starting, then, with a primate base, the increased human neocortical size has provided a precision and range of dexterity that is fundamental to human tool use and readily preempted for various sign languages. Apes, for instance, possess sufficient manual skill and cognitive capacity to produce a large number of signs of the American Sign Language of the Deaf. These signs, however, tend to be crudely and imprecisely formed (Terrace, 1979, 1980). Were the apes to invent a sign language of their own, this imprecision would limit the potential range and versatility of linguistic expression. A humanlike gestural precision, however, could readily be derived by imposing increased manual differentiational skills upon the ape pattern. Similarly, other primates can distinguish and produce phonemic utterances (Snowden, 1982). Increased neuronal interconnectivity would result in a transition from a system of some phonemic versatility to the highly versatile phonemic system characteristic of human language. Hence, no qualitatively new neural functions would be needed, but rather a quantitative expansion of neocortical differentiational/constructional skills already present in other animals. The importance of brain-size is most evident when considering the effects of superpositioning expanded constructional capacity upon a wide range of differentiated manual and phonemic behaviors. Chimpanzees, for instance, spontaneously use tools in the wild (Boesch and Boesch, 1981,1983,1984α, 1984Z»; Jones and Sabater Pi, 1969; Kortlandt, 1962, 1965, 1967, 1972; Kortlandt and Kooij, 1963; McBeath and McGrew, 1982; McGrew, 1974; McGrew and Rodgers,
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1983; Nishida and Hiraiwa, 1982; Struhsaker and Hunkeler, 1971; Van Lawick-Goodall, 1968,1970). Their tool-using behaviors, however, consist of applying one tool-using scheme at a time to meet a single end, such as, for instance, probing for termites, or bashing nuts. Among humans, the greatly expanded association areas permit divergent tool-using schemes to be subordinated into a single goaldirected tool-using sequence. This skill is essential to modern human subsistence patterns as well as to all of our material culture. Consider, for instance, the tool-using sequences involved in the 'simple' act of gathering tubers. First, a digging stick must be sharpened with a stone, and a container constructed; then the tuber must be dug from the ground using the stick, and be placed in the container for transport. Eventually, the food item may be pounded by a hammerstone and cooked in a pot. Some of these tool-using skills are well within the range of spontaneous ape behavior. No ape, however, has been observed stringing them together in an organized pattern to meet a single goal. In other words, apes already possess some of the fundamental 'building blocks' of a human-like culture, but they have insufficient cortically-mediated constructional capacity to join them together in a human-like manner. Similarly, apes can make tools, but they do so primarily by subtractive means: e. g. removing side twigs from a branch. Humans can construct tools in a hierarchical fashion: e.g. creating first a spear point and a shaft, then joining the two together to make a compound tool. Analogous processes occur linguistically. Monkeys possess rudimentary syntax and vocal naming skills, and apes can string symbolic gestures together in a repetitive or vaguely grammatical fashion (Seyfarth and Cheney, 1982; Snowden, 1982; Terrace, 1979, 1980). The human neocortex permits an expansion of these nonhuman primate capacities. As a result, humans can organize many independent vocalizations and gestures into complex grammatical constructs. Consequently, many ape/human behavioral divergences including critical aspects of the linguistic process reflect expanded differentiational and constructional capacities. Hence, in the absence of clear qualitative dichotomies between apes and humans, the most parsimonious explanation is that language is a brain-size mediated expansion of processes already present in the primates. This emphasis on size does not, of course, mean that all areas of the cortex have increased by the same amount or that an increase
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in one area of the brain is functionally equivalent to an increase in any other. Rather, it implies that no qualitatively distinct neural functions are needed. Clear functional differences do exist between cortical sensory, motor and association areas. For this reason, increases in some cortical areas would be expected to provide potentially much greater linguistic impact than increases in others. In particular, Broca's area, the inferior parietal and temporal association areas, and the frontal lobes are all thought to have experienced relative size increases in human evolution and are of potentially critical importance with respect to expanded human behaviors (Passingham, 1973, 1975). Broca's area, for instance, mediates speech production. The inferior parietal association area is critical for object naming, grammar, gestural imitation and the appropriate use and orientation of objects; the frontal lobes are known to play a fundamental role in planning goal-oriented action sequences, and the temporal association areas are critical for remembering stories and events in sequential order (J. W. Brown, 1972; Geschwind, 1965; Lancaster, 1968; Luria, 1966; Milner, 1967; Warren and Akert, 1964).
Fossils, tools and the evolution of language The recognition of potential brain-size/linguistic interdependencies paves the way for evolutionary reconstruction based on the fossil record, and suggests that increased cranial capacity would have been accompanied by the application of expanded differentiational and constructional skills to all aspects of the linguistic process. The result would have been increasing phonetic precision and advances in grammatical capacity with a resulting increase in precision of reference and breadth of conversational content. In addition, of course, increased brain size would have provided increased information storage capacity, for linguistically transmitted information. Fossils, in and of themselves, however, cannot suffice for the complicated task of linguistic reconstruction. Despite probable interdependencies, a precise correlation between brain-size and linguistic capacity would not be expected over narrow brain-size ranges. The brain does, after all, mediate behaviors other than language. Moreover, within-species variations in cranial capacity
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have so far proven impossible to correlate with behavioral phenomena (Tobias, 1970). Supplementation of brain size analyses with those of stone tool manufacture, however, is likely to yield a finer predictive instrument (Falk, 1980; Holloway, 1969,1972). In modern humans, for instance, object use is heavily mediated by the inferior parietal association area, the same neural region known to mediate object naming and grammar (Geschwind, 1965; Luria, 1966). Moreover, detailed comparative analyses of object use, object manufacture and language suggest a common underlying cognitive structure (Greenfield, 1978; Holloway, 1969; Reynolds, 1983). Hence, tool-use and language share acommon neurological base and would have evolved in tandem. Among modern humans, tool use and language mature in synchrony (Bates, et ah, 1980), and tools and other forms of object manipulation appear to serve both as a primary motivating force for linguistic use and as a primary organizer of linguistic thought. The conversation of small children just beginning to talk, for instance, is heavily focused on objects: e. g. object names, object locations, object appearance and disappearance, and the actions of humans and objects. At a later stage, a complicated interplay between emerging linguistic function, abstract thought and overt constructional acts emerges (Piaget, 1954). In fact, it appears that it is only through the continued arrangement of objects into groups, and play with objects, that children develop classificatory and mathematical capacities. If modern humans require repeated experience with objects in order to develop mature language capacity, it is unlikely that early hominids could have possessed anything resembling the language capacities of modern adults, prior to the point at which they began to use and manufacture rather advanced tools. At the same time, it is probable that in early hominids, as in modern man, the use and manufacture of tools provided an impetus for speech, and reflected a cortical organization that would render speech possible. Fossil evidence indicates that hominid brain/body size ratios first exceeded those of the apes in certain species of the genus, Australopithecus, who inhabited East and South Africa approximately one to four million years ago (Falk, 1985; Holloway, 1972,1976; Holloway and De La Coste-Lareymondie, 1982; Holloway and Post, 1982). These forms possessed cranial capacities of about 400—500 cc. This
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compares to an average chimpanzee cranial capacity of 300—400 cc., and a modern human average of about 1300 cc. By two million years ago, brain size had advanced to over 600 cc in the East African Homo habilis. From habiline times onward, the brain evolved slowly, reaching a capacity of about 1000 cc. in Homo erectus forms of about 500,000 years ago, but achieving its modern size only with the advent of Homo sapiens in the last 200,000 years (Holloway, 1981; Kochetkova, 1978; Tobias, 1971). Two neural regions, the frontal and parietal lobes, may have reached their modern size and external configuration even later with the advent of Cromagnon man, 35,000 years ago. These data imply that language evolved slowly, perhaps emerging in rudimentary form in the Australopithecines two to five million years ago, but not reaching fully modern adult complexity until as recently as 35,000 years ago (Gibson, 1983). The evolutionary picture provided by the tools precisely parallels that of the brain. Clearly manufactured stone tools appear about 2.0 million years ago during the transition between Australopithecine and habiline times (Coppens, et al., 1976). Manufacturing techniques, however, advance very slowly and do not exhibit the influence of fully modern cognitive levels until the last 35,000 years (Binford, 1982; Gibson, 1985). A closer focus on changes in stone tool manufacture allows us to derive a tentative model of language evolution (Tab. 1). Table 1. Time frame for the evolution of language Hominid
Approximate Time Frame
Approximate Cranial Capacity
Postulated language abilities
Australopithecus
1 to 4 million years B.P.
4 0 0 - 5 5 0 c.c
Communication of Desires
Homo habilis
1.5 to 2.5 million years B.P.
6 0 0 - 7 5 0 c.c
Collaborations in action
Homo erectus
1.5 million to 300,000 years B.P.
9 0 0 - 1 0 0 0 c.c
Beginning Collaborations in Knowledge
Homo sapiens
100,000 years B.P. to present
1350 c.c
Advanced Collaborations in Knowledge
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The earliest manufactured stone tools of approximately 1.5 to 2.5 million years ago were simple in form, consisting of pebbles from which a few flakes had been removed to produce a sharpened edge. Detailed analysis has indicated that the cognitive skills needed to produce them were rudimentary in comparison to those exhibited not only by adult humans, but even by fairly young children (Wynn, 1981). Nevertheless, these early tools demanded the use of a tool to make a tool, a sequential constructional task accomplished to this date by only one intensively trained laboratory ape (Wright, 1972). Consequently, the tool-maker was clearly utilizing cognitive capacities which, no matter how rudimentary, had already begun the transition from ape to man. Given the evidence of enlarged brain size, both Australopithecus and Homo habilis may have possessed sufficient cognitive capacity to produce these simple tools, although Homo habilis, with his larger brain, appears the more probable tool-maker of the two. Irrespective of whether or not Australopithecus made tools, he almost certainly used them, as stone tool making would have been preceded by a lengthy period of tool use. While neither the brains nor the tools of Australopithecus and Homo habilis suggest that these forms possessed modern linguistic capacities, certainly their linguistic potential would have at least matched that of the average modern ape. Apes in captivity can use symbolic gestures not only to name objects, but also to request food, objects, help in manipulating objects/tools, and to express desires to be picked up, tickled, taken out or otherwise catered to (Fouts, 1973; Gardner and Gardner, 1969, 1980; Miles, 1983; Terrace, 1979, 1980). It is not unreasonable to assume that Australopithecus and Homo habilis could have done the same, given sufficient motivation. These ape-language skills very much parallel the "communications of desire" which characterize the discourse of young children just beginning to talk (Piaget, 1955). In both the human child and the captive ape these communications are motivated by a situation of dependency upon an human caretaker for the provision of food and other sustenance. A similar dependence on assistance from others does not occur in wild apes. Such a dependency may, however, have existed in early hominid children in situations in which skilled tool use was essential for the procurement of food (Gibson,
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1983; Parker and Gibson, 1979) or in early hominid adults if they were indeed sharing food (Isaac, 1978). Moreover, given his advanced brain size and tools, Homo habilis, at least, would have possessed a linguistic potential beyond that of any ape. Although the issue is controversial, apes appear to possess borderline sentence constructional skills (Miles, 1983; Patterson and Linden, 1981; Rumbaugh, 1977; Terrace, 1979, 1980). Homo habilis would have been at least one step ahead of the apes in this regard. Almost certainly, he could have constructed sentences of the form, actor-action-object, typically used by very young children (R. Brown, 1972). Insight into the functional utility of rudimentary grammatical skills can be gained by observing conversations between children. According to Piaget (1955), the play activities of children between three and five years of age often involve linguistic "collaborations of action," characterized by conversations of the form "I'll do this; you do that," and accompanied by much gesturing and pointing. If Homo habilis possessed a similar level of conversational potential, he could well have engaged in linguistically-mediated collaborative efforts. With the appearance of Homo erectus in Africa approximately 1.5 million years ago, both tools and brain size manifest a quantum jump. By about 500,000 years ago, Homo erectus was producing very finely made, bilaterally symmetrical hand axes, the construction of which required a series of sequential steps, organized in accordance with a preconceived mental image (Wynn, 1979). Nevertheless, the manufacturing capabilities of Homo erectus were still rudimentary by modern standards. For one thing, erectus tools lacked variety in shape and form. For another, Homo erectus was not yet producing compound tools of separate components joined together in a hierarchical fashion, e. g. spear point and shaft. Nor was he utilizing complex materials such as bone and ivory, which require complicated, multistepped curing processes. These attainments, like brain structure, reached their modern form only with the advent of Cromagnon man, 35,000 years ago (Kochetkova, 1978). What, then, are we to make of the linguistic skills of Homo erectus? According to Wynn (1979), Homo erectus tools reflect a cognitive capacity equivalent to at least that of a seven-year-old child. This interpretation does not seem unreasonable if one compa-
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res the conceptual skills needed to produce a hand-axe with those needed to make simple modern drawings. It is not until the ages of five to seven, for instance, that children possess the cognitive skills needed to draw a diamond, a task that certainly appears no more complex than that of constructing a hand-axe. If Wynn (1979) is correct and Homo erectus possessed cognitive skills equivalent to at least those of a seven-year-old child, then it is likely that he had rather advanced linguistic skills indeed. At about seven to nine years of age children develop sufficient precision of reference and grammatical skill to demarcate distant and absent objects and events by language alone without accompanying pointing and gestures (Karmiloff-Smith, 1979; Piaget, 1955). At about this age, children also begin to recount stories and events in actual sequential order. The maturation of these and other capacities results in a major communicative advance. Among young children, linguistic comprehension is generally poor except when the conversation focuses on events and objects which form part of the common experience. With the increased linguistic and cognitive skills of later childhood comes the capacity for mutual understanding, even when conversing about events experienced by only one member of the group. The result is a "collaboration in knowledge" (Piaget, 1955). Children seek to come to common agreements about the 'facts' of the physical and social world, by communicating individually obtained knowledge and by arguments accompanied for the first time by attempts at 'proof and the invocation of rules. If Homo erectus possessed the cognitive capacities of later childhood, he, too, should have been able to converse about 'facts' and linguistically collaborate in the acquisition of knowledge. Clues to the potential utility of this ability can be gained from examining the use of such collaborative knowledge among modern huntergatherers. Successful food procurement among these groups demands a knowledge base far too extensive to be acquired by a single individual, either on his own or by direct observation of the behavior of other humans in all potentially relevant contexts. Gatherers, for instance, must be able to identify hundreds of plant species, know precisely where they grow within an approximate fifty mile radius and predict in advance on the basis of climatic factors when they will be ready to harvest. Hunters must be able not only to identify
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numerous species by their tracks alone, but to determine from these tracks when the animal passed by and how fast he was going. Like gatherers, they must have a detailed knowledge of the terrain for miles around and of the specific habitat preferences of each species under varied seasonal conditions (Lee, 1979; Marshall, 1976; Silberbauer, 1981; Smith, 1981; Winterhaider, 1981). The distances traveled by modern groups are such that linguistic communication about animal and plant resources is routine. Hunters, for instance, relay information about harvestable plants encountered during the hunt, while gatherers report any animal sightings. This information is used to plan the next day's hunting and gathering activities. Migratory groups also report on weather and food conditions from quite distant areas. On this basis, future food availability is predicted and seasonal spatial dispersions of the band are planned (Silberbauer, 1981; Winterhaider, 1981). Inaccurate predictions can result in starvation of groups who find themselves trapped in areas of food shortage during periods when climate or other conditions render travel impossible. Information from traveling human groups also plays an indispensable role in predicting where and when migratory herds are likely to appear (Heffley, 1981). Homo erectus inhabited temperate climates where food resources may have been more difficult to locate than on the open savannah. Consequently, it may well have been to his benefit to communicate individually acquired knowledge of foods and their locations by linguistic means. Certainly, if he had the cognitive capacity of a seven-year-old child he could have done so. Advanced planning of seasonal food dispersions on the basis of climatic and other conditions, however, obiously requires a high degree of intelligence and 'frontal lobe' predicting skills. There is no evidence that humans subsisted on mass kills of migratory herds, or inhabited the climatic extremes of the winter subartic or semidesert until the advent of Cromagnon man about 35,000 years ago (Binford, 1982). These habitat and subsistence advances coincided with the achievement of modern brain form, the explosion in the variety and complexity in tools and the burgeoning of art (Kochetkova, 1978). It is most likely, then, that the final cognitive and linguistic advances arose only with the advent of Homo sapiens, possibly as late as 35,000 years ago. The highly advanced "communi-
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cations of knowledge" which began at this time represented the final flowering of a brain size based communication trend begun by Homo erectus.
Conclusion An examination of the potential effects of increased cortical size suggests that modern linguistic capacities can be explained as brainsize mediated expansions of communicative skills that exist in rudimentary form in nonhuman primates. It further suggests that as brain size expanded in the fossil record, gradual increases would have occurred in grammatical skills, precision of reference, and information storage capacity. These considerations are combined with an analysis of tool use to provide a model of the gradual evolution of language from Australopithecus to Homo sapiens. References Armstrong, E. 1982 Mosaic evolution in the primate brain: Differences and similarities in the hominid thalamus. In E. Armstrong and D. Falk (eds.), Primate Brain Evolution. 131 — 162. New York: Plenum. Bates, E., L. Benigni, I. Bretherton, L. Camaioni and V. Volterra 1980 The Emergence of Symbols: Communication and Cognition in Infancy. New York: Academic Press. Binford, L. R. 1982 Commentary on R. White, 'Rethinking the Middle/Upper Paleolithic transition.' Current Anthropology 23. 177 — 181. Bishop, A. 1962 Control of the hands in lower primates. In J. Buettner-Janusch (ed.), Annals of the New York Academy of Sciences 102. 181 — 514. Boesch, C. and H. Boesch 1981 Sex differences in the use of natural hammers by wild chimpanzees: A preliminary report. Journal of Human Evolution 10. 585 — 593. 1983 Optimisation of nut cracking with natural hammers in chimpanzees. Behavior 83. 265-286. 1984a Possible causes of sex differences in the use of natural hammers by wild chimpanzees. Journal of Human Evolution 13. 415—440. 19846 Mental map in wild chimpanzees: An analysis of hammer transports for nut cracking. Primates 25. 160 — 170. Bonin, G. Von and P. Bailey 1947 The neocortex of 'Macaca mulatta.' Illinois Monographs in the Medical Sciences 4. 1 — 163.
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Brown, J. W. 1972 Aphasia, Apraxia and Agnosia. New York: Thomas. Brown, R. 1972 The first sentences of child and chimpanzee. In T. A. Sebeok and J. Umiker-Sebeok (eds.), Speaking of Apes. 85 — 101. New York: Plenum. Buettner-Janusch, J. 1966 Origins of Man. New York: Wiley. Coppens, Y., F. C. Howell, G. LI. Isaac and R. E. F. Leakey 1976 Earliest Man and Environs in the Lake Rudolf Basin. Chicago: University of Chicago Press. Crosby, Ε., T. Humphrey and E. W. Lauer 1962 Correlative Anatomy of the Nervous System. New York: Macmillan. Davenport, R. K. and C. M. Rogers 1970 Intermodal equivalence in apes. Science 168. 279—280. Davenport, R. K., C. M. Rogers and I. S. Russell 1973 Cross-modal perception in apes. Neuropsychologia 11. 21 —28. Dewson, J. H. and A. C. Burlingame 1975 Auditory discrimination and recall in monkeys. Science 187 — 268. Duffy, F. H. and J. L. Buschfiel 1971 Somatosensory system: Organizational hierarchy from single units in monkey Area 5. Science 172. 273 — 275. Falk, D. 1978 Cerebral asymmetry in monkeys. Acta Anatomica 101. 195 — 199. 1980 Language, handedness and primate brains: Did the Australopithecines sign? American Anthropologist 82. 71—78. 1985 Hadar Al 162—28 endocast as evidence that brain enlargement preceded cortical reorganization in hominid evolution. Nature 313. 45-47. Fouts, R. S. 1973 Acquisition and testing of gestural signs in four young chimpanzees. Science, 180, 973-980. Galaburda, A. M. and D. N. Pandya 1982 Role of architectonics and connections in primate brain evolution. In E. Armstrong and D. Falk (eds.), Primate Brain Evolution. 203 — 216. New York: Plenum. Gallup, G. G. 1979 Self awareness in primates. American Scientist 67. 417—421. Gardner, R. A. and Β. T. Gardner 1969 Teaching sign language to a chimpanzee. Science 165. 664—672. 1980 Comparative psychology and language acquisition. In T. A. Sebeok and J. Umiker-Sbeok (eds.), Speaking of Apes. 287 — 330. New York: Plenum. Geschwind, Ν. 1965 Disconnection syndromes in animals and man. Brain 88. 237 — 294. Gibson, K. R. 1978 Asking the right questions: Other approaches to the mind-brain problem. The Behavioral and Brain Sciences 1. 354—355.
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Comparative neuroontogeny and the constructionist approach to the evolution of the brain, object manipulation and language. In E. de Grolier (ed.), Glossogenetics. The Origin and Evolution of Language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 37—62. Chur, Switzerland: Harwood Academic Publishers. Quantity or quality: A behavioral approach to the mind-brain problem. American Journal of Physical Anthropology 63. 162 — 163. Has the evolution of intelligence stagnated since Neanderthal Man? In G. Butterworth, J. Rutkowska and M. Scaife (eds.), Evolution and Developmental Psychology. 102—114. Brighton, England: The Harvester Press.
Greenfield, P. 1978 Structural parallels between language and action in development." In A. Lock (ed.), Action, Gesture, and Symbol. 415—445. New York: Academic Press. Gross, C. G., C. E. Roche-Miranda and D. B. Bender 1972 Visual properties of neurons in the inferotemporal cortex of the macaque. Journal of Neurophysiology 35. 96—111. Heffley, S. 1981 The relationship between Northern Athapaskan settlement patterns and resource distribution: An application of Horn's model. In B. Winterhalder and E. A. Smith (eds.), Hunter-Gatherer Foraging Strategies. 126 — 147. Chicago: University of Chicago Press. Hofman, M. A. 1983 Encephalization in hominids: Evidence for the model of Punctualism. Brain, Behavior, and Evolution 22. 102 — 107. Holloway, R. L. 1968 The evolution of the primate brain: Some aspects of quantitative relationships. Brain Research 7. 121 — 172. 1969 Culture, a human domain. Current Anthropology 10. 395—412. 1972 Australopithecine endocasts, brain evolution in the Hominoidea, and a model of hominid evolution. In R. Tuttle (ed.), The Functional and Evolutionary Biology of Primates. 185—204. Chicago: Aldine. 1976 Some problems of hominid brain endocast reconstruction, allometry and neural reorganization. In P. V. Tobias and Y. Coppens (eds.), Colloquium VI of the Xlth Congress of the UISPP Nice, 1976 Congress. Pretirage. 66-119. 1979 Brain size, allometry and reorganization: A synthesis. In Μ. E. Hahn, Β. C. Dudek and C. Jensen (eds.), Development and Evolution of Brain Size. 59 — 88. New York. Academic Press. 1981 The Indonesian 'Homo erectus' brain endocasts revisited. American Journal of Physical Anthropology, 55. 503 — 521. Holloway, R. L. and C. M. De La Coste-Lareymondie 1982 Brain endocast asymmetry in pongids and hominids: Some preliminary findings on the paleontology of cerebral dominance. American Journal of Physical Anthropolgy 58. 101-110.
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Holloway, R. L. and D. Post 1982 The relativity of relative brain size measures and hominid evolution. In E. Armstrong and D. Falk (eds.), Primate Brain Evolution, Methods and Concepts. 57 — 76. New York. Plenum. Isaac, G. LI. 1978 The food sharing behavior of protohuman hominids. Scientific American 238(4). 90-108. Jenson, H. J. 1973 Evolution of the Brain and Intelligence.New York: Academic Press. 1979 The evolution of diversity in brain size. In M. Hahn, C. Jensen, and B. Dudek (eds.), Development and Evolution of Brain Size: Behavioral Implications. 29 — 57. New York: Academic Press. 1982 Allometry, brain size, cortical surface, and convolutedness. In E.Armstrong and D.Falk (eds.), Primate Brain Evolution. 77—84. New York: Plenum. Jones, C. and J. Sabater Pi 1969 Sticks used by chimpanzees in Rio Muni, West Africa. Nature 223. 100-101. Karmiloff-Smith, A. 1979 A Functional Approach to Child Language. A Study of Determiners and Reference. Cambridge, &c.: Cambridge University Press. Kochetkova, V. I. 1978 Paleoneurology. Washington: Winston. Kortlandt, A. 1962 Chimpanzees in the wild. Scientific Amerian 206. 128-138. 1965 How do chimpanzees use weapons when fighting leopards? American Philosophical Society Yearbook. 327-332. 1967 Experimentation with chimpanzees in the wild. In D. Starck, R. Schneider and H. J. Kuhn (eds.), Neue Ergebnisse der Primatologie. 208-224. Stuttgart: Fischer. 1972 New Perspective in Ape and Human Evolution. Amsterdam: Stichting voor Psychobiologie. Kortlandt, A. and M. Kooij 1963 Protohominid behavior in primates. In J. Napier, and N. Barnicott (eds.), The Primates — Symposium of the Zoological Society of London 10. 61 —68. London: Academic Press. Krieg, W. J. S. 1954 Connections of the Frontal Lobe of the Monkey. Springfield: Thomas. Kuypers, H. G. J. 1962 Corticospinal connections: Postnatal development in the Rhesus monkey. Science 138. 678-680. Lancaster, J. B. 1968 Primate communication systems and the emergence of human language. In P. C. Jay (ed.), Primates: Studies in Adaptation and Variability. Pp. 439-457. New York, Holt, Rinehart and Winston. Lawick-Goodall, J. Van 1968 The behaviour of free ranging chimpanzees in the Gombe Stream Reserve. Animal Behaviour Monographs 1. 161 — 311.
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Tool using in primates and other vertebrates. In D. S. Lehrman, R. A. Hinde and E. Shaw (eds.), Advances in the Study of Behavior. 3. 195 — 248. New York: Academic Press.
Lee, R. B. 1979 The IKung San. Cambridge, England: Cambridge University Press. LeMay, Μ., M. S. Billig and N. Geschwind 1982 Asymmetries of the brains and skulls of nonhuman primates. In E. Armstrong and D. Falk (eds.), Primate Brain Evolution: Methods and Concepts. 263—278. New York: Plenum. Luria, A. 1966 Higher Cortical Functions in Man. New York: Basic Books. McBeath, Ν. M. and W. C. McGrew 1982 Tools used by wild chimpanzees to obtain termites at Mt. Assirik, Senegal: The influence of habitat. Journal of Human Evolution 11. 65-72. McGrew, W. C. 1974 Tool use by wild chimpanzees in feeding upon driver ants. Journal of Human Evolution 3. 501-508. McGrew, W. C. and Μ. E. Rodgers 1983 Chimpanzees, tools and termites: New Record from Gabon. American Journal of Primatology 5. 171 — 174. Marshall, L. 1976 The IKung of the Nyae Nyae. Cambridge, MA: Harvard University Press. Menzel, Ε. W. 1973 Leadership and communication in young chimpanzees. In W. Montagna (ed.), Proceedings of the Fourth International Congress of Primatology. 1. 192-225. Basel: Karger. Miles, H. L. 1983 Two way communication with apes and the evolution of language. In E. de Grolier (ed.), Glossogenetics. The Origin and Evolution of Language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 201—210. Chur, Switzerland: Harwood Academic Publishers. Milner, B. Brain mechanisms suggested by studies of the temporal lobes. In F. L. 1967 Darley (ed.), Brain Mechanisms Underlying Speech and Language. 122-145. New York: Grune and Stratton. Mountcastle, V. 1978 An organizing principle for cerebral function: The unit module and the distributed system. In G. M. Edelmann and V. B. Mountcastle (eds.), The Mindful Brain. 7 - 5 0 . Cambridge, MA: M.I.T. Press. Myers, R. 1976 Comparative neurology of vocalization and speech: Proof of a dichotomy. In S. R. Hamad, H. D. Steklis, and J. Lancaster (eds.), Origins and Evolution of Language and Speech. 280. 745 — 757. New York: Annals of the New York Academy of Sciences.
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Napier, J. R. 1961 Prehensibility and opposability in the hands of primates. Symposium of the Zoological Society. 5. 115 — 132. Nishida, T. and M. Hiraiwa 1982 Natural history of a tool-using behavior by wild chimpanzees in feeding upon wood-boring ants. Journal of Human Evolution 11. 73-99. Nishida, T. and S. Uehara 1980 Chimpanzees, tools and termites: Another example from Tanzania. Current Anthropology 21. 671-672. Oakley, K. P. 1959 Man the Tool Maker. Chicago: University of Chicago Press. Pandya, D. N. and H. G. J. Kuypers (1969) Cortico-cortical connections in the Rhesus monkey. Brain Research 13. 13 — 36. Parker, S. T. and K. R. Gibson 1979 A model of the evolution of language and intelligence in early hominids. The Behavioral and Brain Sciences 2. 367—407. Passingham, R. E. 1973 Anatomical differences between the neocortex of man and other primates. Brain, Behavior, and Evolution 7. 337 — 359. 1975 Changes in the size and organization of the brain of man and his ancestors. Brain, Behavior, and Evolution 11. 73—90. Patterson, F. G. 1978 The gestures of a gorilla: Language acquisition in another pongid. Brain and Language 5. 72—97. Patterson, F. G. and E. Linden 1981 The Education of Koko. New York: Holt, Rinehart and Winston. Piaget, J. 1952 The Origins of Intelligence in Children. New York: Norton. 1954 The Construction of Reality in the Child. New York: Basic Books. 1955 The Language and Thought of the Child. Cleveland, sc.: World. Pucetti, R. and R. W. Dykes 1978 Sensory cortex and the mind-brain problem. The Behavioral and Brain Sciences 1. 337 — 375. Reynolds, P. C. 1980 The programmatic description of simple technologies. Journal of Human Movement Studies 6. 38 — 74. 1981 On the Evolution of Human Behavior. Berkeley and Los Angeles: University of California Press. 1982 The primate constructional system: The theory and description of instrumental object use in humans and chimpanzees. In M. Von Cranach and R. Harre (eds.), The Analysis of Action. 343 — 385. Cambridge, England: Cambridge University Press. 1983 Ape constructional ability and the origin of linguistic structure. In E. de Grolier (ed.), Glossogenetics. The Origin and Evolution of Language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 185—200. Chur, Switzerland: Harwood Academic Publishers.
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Rumbaugh, D. 1977 Language Learning by a Chimpanzee. New York: Academic Press. Seyfarth, R. M. and D. Cheney 1982 How monkeys see the world: A review of recent research on East African vervet monkeys. In C. T. Snowden, C. H. Brown and M. R. Petersen (eds.), Primate Communication. 239—252. Cambridge, England: Cambridge University Press. Silberbauer, G. B. 1981 Hunter and Habitat in the Central Kalahari Desert. Cambridge, England: Cambridge University Press. Smith, E. A. 1981 An application of optimal foraging theory to the analysis of the hunter-gatherer group size. In B. Winterhaider and E. A. Smith (eds.), Hunter-Gatherer Strategies. 36 — 65. Chicago: University of Chicago Press. Snowden, C. T. 1982 Linguistic and psycholinguistic approaches to primate communication. In C. T. Snowden, C. H. Brown, and M. R. Petersen (eds.), Primate Communication. Cambridge, England: Cambridge University Press. Steklis, H. and M. Raleigh 1979 Neurobiology of Social Communication in Primates. New York: Academic Press. Struhsaker, Τ. T. and P. Hunkeler 1971 Evidence of tool-using by chimpanzees of the Ivory Coast. Folia Primatologia 15. 212-219. Sutton, D. 1979 Mechanisms underlying vocal control in nonhuman primates. In H. Steklis and M. Raleigh (eds.), Neurobiology of Social Communication in Primates. 45 — 68. New York: Academic Press. Terrace, H. S. 1979 Nim: A Chimpanzee who Learned Sign Language. New York: Knopf. 1980 Is problem solving language? In T. A. Sebeok and J. Umiker-Sebeok (eds.), Speaking of Apes. 385—405. New York: Plenum. Tobias, P. V. 1970 Brain size, grey matter and race — Fact or fiction? American Journal of Physical Anthropology 32. 3 — 26. 1971 The Brain in Hominid Evolution. New York: Columbia University Press. Warren, J. M. and K. Akert 1964 The Frontal Granular Cortex and Behavior. New York: McGraw Hill. White, L. 1959 The concept of culture. American Anthropologist 61. 227 — 251. Winterhaider, Β. 1981 Foraging strategies in the boreal forest. In B. Winterhaider and E. A. Smith (eds.), Hunter-Gatherer Strategies. 66—98. Chicago: University of Chicago Press.
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Wright, R. V. S. 1972 Imitative learning of a flake stone technology: The case of an orangutan. Mankind 8. 296-306. Wynn, T. G. 1979 The intelligence of later Acheulean hominids. Man 14. 371 —391. Wynn, T. G. 1981 The intelligence of Oldowan hominids. Journal of Human Evolution 10. 529-541.
Laryngeal descent in 40,000 year old fossils Grover S. Krantz
Abstract Cranial anatomy of human fossils since 40,000 years ago suggests a two-stage descent of the larynx. The first stage allows controlled exhalation through the mouth; the second stage results in the full development of the pharynx. Accordingly, the earliest phonemic languages should have consisted of consonants, with neutral vowels; only much later languages would have included phonemic vowels. Linguistic reconstructions support this conclusion. A major anatomical change occurred in the human skull about 40,000 years ago. The change was world-wide, rapid, nearly simultaneous, and it coincided with major advances in cultural complexity. The human type which preceded this change is here termed Homo erectus; the type which followed is called Homo sapiens. This typology differs from that in common use today, because it would place Neanderthals and other late Pleistocene fossils in the erectus category. In spite of their modern brain size, Neanderthal skulls display essentially the same cranial traits by which we have long defined erectus. These include flattened braincases with large bases, tucked up area around the foramen magnum, small and inflected mastoid processes, slight basioccipital slope, large faces that project anteriorly, protruding brow ridges, large teeth, and retreating chins (see Figs. 1 and 2). It has already been shown, in detail, how all these traits automatically are transformed into the modern condition by the laryngeal descent (Krantz, 1980). This descent of the larynx, down from the level of the palate, served to produce the elongated pharynx and the separation of the epiglottis from the soft palate (see Fig. 3). This separation permits easy exhalation through the mouth, and the pharynx becomes a
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Figure 1. The Neanderthal skull (left) has a large and projecting face, expecially from brow ridges to lower incisors. The braincase bulges out behind and is tucked up at the bottom. Its mastoid processes are small. The sapiens skull has a smaller face, drawn back, and vertically compressed. The back is drawn in, and the bottom stands downward. The mastoid processes are larger.
Figure 2. The Neanderthal skull (left) has bulging sides in the basal area, while the foramen magnum and condyles are tucked up. Mastoid processes are short and inflected. The sapiens skull is narrower at the base, while the foramen magnum and condyles are drawn down. The mastoid process is longer and more vertical, with the tips maintaining their lateral position.
major vowel-producing organ. Because of these vocal implications, I ascribed the anatomical change into modern man to the development of speech as the major delivery system for language. N o other mechanism explains more than a fraction of the traits distinguishing modern man. Two significant sets of anatomical changes occurred in the human skull between mid-Pleistocene erectus and modern sapiens, one some 200,000 years ago or more, and the other some 40,000 years ago. It is generally recognized that the earlier set of changes was the
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Figure 3. Contrasting anatomy of Neanderthal (left) and sapiens heads. Bone is shown in stipple and soft parts in outline. In Neanderthal the epiglotis is reconstructed as closely approaching the soft palate. It has a high location of the vocal cords at the level of the fourth cervical vertebra. The foramen magnum is located high in relation to the palate, and the basioccipital slope is shallow. In sapiens the epiglottis has moved about two cm down, and farther away from the soft palate, leaving a wide gap for exhaling through the mouth. This same gap represents the pharynx, or vowel modifying organ. The foramen magnum is drawn down one cm, and sharply increases the basioccipital slope. The vertebrae are also moved down in relation to the palate. The vocal cords are displaced even farther down, now even with the fifth cervical vertebra. The sapiens tongue is set down into the pharynx, and drawn backwards — pulling most of the face back proportionally.
lesser of the two. Given this contrast, it would appear obvious to assign subspecific distinction to the lesser change, and specific distinction to the greater one. Accordingly, Neanderthal may be used here to illustrate the erectus condition in contrast with sapiens, and brain size is thereby held constant. (In some parts of the world an increase in brain size was apparently simultaneous with the development of the sapiens cranial anatomy). In this paper I divide the sapiens transition into two stages. The first consists of the modernization of the braincase and the partial withdrawal of the face; the second is the completion of the facial withdrawal. This two-part scenario was first suggested by observing two fossil human skulls that appeared to show intermediate stages. The necessary core of sapienization is the lowering of the larynx about two cm farther down the neck from its ape-like position, and
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Figure 4. Essential change that must be accomplished from the Neanderthal to the sapiens head design. Vocal cords move down into the neck, and the epiglotis moves down the same distance, leaving the palate in its original location.
away from the soft palate (see Fig. 4). If the larynx is to retain its position adjacent to the fourth cervical vertebra, than that vertebra itself must move down and away from the palate as well. Some of this is accomplished by a slight increase in heights of the cervical vertebrae, as compared with apes of similar body size. Most of this move results from a drawing down of the entire cervical column, including its area of attachment on the bottom of the skull. This downward movement of the occipital condyles and foramen magnum automatically alters the braincase into the sapiens design, as shown in my previous paper (Krantz, 1980). It will also draw the tongue somewhat back and down the throat to begin the formation of the enlarged pharynx. Because of this tongue withdrawal, most of the face also must draw back (see Fig. 5, left). A second stage in the transition consists of moving the larynx another cm down the neck, this time in relation to the vertebrae. It now comes to lie adjacent to the fifth instead of the fourth cervical. The full pharynx is now formed, the tongue has drawn back and down still more, and facial withdrawal now reaches the sapiens condition (see Fig. 5, right). There is no obvious reason why the larynx should be so 'reluctant' to move in relation to the vertebrae — there being so little attachment between them. It is the fossils themselves that suggest this
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well. This leads to all the sapiens alterations of the braincase. Tongue movement makes only a partial retraction of the face. Second stage (right) moves the larynx and vocal cords down in relation to the vertebrae — now even with the fifth cervical — and the tongue moves farther down and draws the face farther back. This second step elongates the nerves that feed the larynx and makes them vulnerable
of erectus design, except for greater slope of basioccipital. Rear view shows some narrowing of the cranial base. These traits might also be within the normal rage of variation in erectus, long before the transformation.
sequence of moves. I can only speculate on problems like lengthening of the nerves that feed the larynx, and perhaps their increasing vulnerability to infection. The Rhodesian skull from the late Pleistocene of southern Africa shows what may be the very beginnings of sapienization. Its basioccipital is quite sloped, and the side walls of the braincase are drawn inward slightly. On the other hand, its face is as large and projecting as anything found in the fossil record (see Fig. 6). It might represent
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an individual from a population that had recently begun the transition to speech production, and thus it shows only a slight change in the braincase, but none in the face. It is at least equally possible that it is from a fully erectus population and just happens to show some of the variation that would only later be selected for. At present, the arguments about its date (30,000 to over 100,000 years) stem from diverse data, and are unresolved. From Palestine we have skull V of the Skhul cave population. This is unquestionably an individual on the sapiens side of the speech transition, but one that still is less than modern. It shows the fully sapient braincase, but has a face that is intermediate between the projecting Neanderthal design and the withdrawn modern type (see Fig. 7). One could reasonably postulate that the first step in sapienization has been completed here, but that the second step of laryngeal sliding has not yet occurred. Its date of about 35,000 years fits this interpretation. From the point of view of speech production, there are important implications in this anatomy. It is not critical that the two steps occurred in the sequence given here; that is just what the fossils seem to indicate. What is critical is that the two anatomical aspects of speech delivery were not quite simultaneous. A half-way lowering of the larynx opened enough space between the soft palate and
Figure 7. Skhul V skull showing full development of sapiens design in the braincase, which logically should have occurred first. The face was only partly reduced, as would be required in the first stage of drawing the tongue down and back. It is likely that the larynx had not yet moved in relation to the vertebrae — that would have completed the transformation.
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epiglottis for easy and controlled exhalation through the mouth. This would have produced only about half of the pharyngeal space we have today. The full lowering of the larynx is not essential for oral exhaling, but it does serve to enlarge the pharynx sufficiently for possible vowel formation and differentiation. Given easy oral exhalation, formation of consonants is simply a matter of using the tongue and lips to affect the air column in a controlled, deliberate, and repeatable manner. These mouth parts were already under excellent neuromuscular control from their previous uses in manipulating food. They were also used to some degree in producing the sounds of a call system. Given half a pharynx, variable vowel production would not be automatic. Not only is a longer pharynx potentially much more productive, but its coming into use at all depends on other developments. The anterior wall of the human pharynx is made up of what corresponds to the rear portion of the ape tongue. While this structure is movable, the exact motions needed to generate the various vowels are not the same as those movements in its previous function as a tongue. There must be a period of time for selection for the appropriate nerve and muscle variations to change this structure into a variable resonating chamber under conscious control. (Neural restructuring for rapid decoding and sound comparisons would also require some time, but these do not show in the anatomy and are not considered here; see Lieberman, 1975). The necessary consequence of the above situation is that the earliest phonemic speech would be one of consonants alone. The only vowel sounds would have been undifferentiated, or at least not under conscious control. A generalized vowel sound (or sounds) would have served merely to separate some of the consonants that were difficult to pronounce adjacently. Eventually our ancestors began to differentiate between, and assign phonemic meanings to, a number of different vowels. I would not hazard assigning a date to this innovation on anatomical data alone. One can only say that we have had the capability for at least a few thousand years, and it was not present when speech began. Linguistic reconstruction of the pre-proto-Indo-European language indicates an absence of differentiated vowels. The date of this prehistoric language is not clear, but 10,000 years ago may well be an approximate time. Proto-Sino-Tibetan apparently was also without vowel differentiation, and this has been at least suggested
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for the earliest ancestor of Afro-Asian. Interestingly, the Caucasian language Kabardian today still lacks clear vowel differentiation in terms of assigning meanings to these sounds. It may be no coincidence that some of the earliest reconstructable languages lacked phonemic vowels. It now appears likely that these languages were spoken by people whose pharyngeal development had not yet achieved the present design. The logical steps of anatomical evolution of the speech apparatus parallel those reconstructed in historical linguistics. Neither method gives exact dates for the introduction of phonemic vowels, but linguistic methods seem the best. A good guess would be that somewhere on the order of 10,000 years ago phonemic vowels first began to come into use. Since then they have tended to become increasingly common. Modern languages do not necessarily reflect the full development of the pharyngeal anatomy of their users. A language cannot exceed the phonological abilities of its speakers, but the language may well lag behind such abilities (as in Kabardian). There appears to be an increase in the number of distinguished vowels in the history of some languages. Is this still a continuing process? Do all present human populations have exactly the same vowel-producing capability? Is it possible that we have not yet evolved to the anatomical and/or neurological limit of our speech potential? Most anthropologists appear to assume a negative answer to all these questions — the human vocal apparatus has been taken as a constant throughout history. I am not at all sure. References Krantz, Grover 1980 Sapienization and speech. Current Anthropology 21(6). 773 — 792. Lieberman, Philip 1975 On the Origins of Language. An introduction to the evolution of human speech. New York: Macmillan.
Part IV Linguistic evidence
Live speech and preverbal communication Ivan Fonagy
Abstract An attempt is made to study the origin of language in the present through the analysis of the irregularities characterizing live speech. It is suggested that phonetic as well as syntactic and semantic rule transgressions, far from being 'noise' are generated by a paralinguistic iconic code. The paper interprets this code as a 'proto-grammar,' and traces it back to a communication system phylogenetically prior to language.
Towards a grammar of deviance 1. The paleo-linguistic (evolutionary) approach proposed in this paper is based on two joined hypotheses: a) the suggestion that rule transgressions characterizing live speech on the phonetic as well as on the syntactic and semantic level, far from being a sort of noise (Fodor and Garret, 1966) or products of a deficient output (Watt, 1970), are generated by a paralinguistic iconic code of rule transgressions; b) the further assumption that the rules constituting this universal code might be traced back to communication-systems prior to language, and to a more primitive way of data processing. I shall attempt to illustrate these assumptions by examples taken essentially from two unrelated languages, French and Hungarian, and corresponding to different kinds of discourse: conversation and poetry, speech of adults and children's talk.
Oral mimetics 2. The permanent presence and the effectiveness of rule-governed distortions are particularly apparent at the phonetic level. Messages
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conveyed by the greater or lesser distortions of speech sounds, called phono-types by Culioli (in his unpublished university lecture of 1970), are responsible for the expressivity of live speech as compared to 'dead letters.' A comparative radiocinematographic study of emotive speech in French and Hungarian clearly shows that similar emotive attitudes are expressed by similar distortions in both (unrelated) languages (see Fonagy, Han, and Simon, 1983). Anger and hatred induce spasmodic tongue movements whilst tenderness is reflected by smooth transitions; anger is characterized by the increase of maxillary angle, and vertical labial distance (21.7 mm for /a/ vs. 14.6 mm in neutral speech for the same vowel); the tongue is advanced for positive feelings, such as joy or tenderness, and withdrawn in the expression of negative attitudes, such as sadness, anger or contempt; aggressive attitudes increase the tension of the articulatory organs, thus the surface of contact is considerably increased in plosives. Aggressive attitudes lengthen at the same time the relative duration of plosives and constrictives and shorten that of vowels; the average duration of /p t k/ varying from 9.0 to 10.0 csec in tender speech, and from 11.6 to 17.1 in the expression of hatred). Such distortion could be interpreted in terms of rule-governed preconscious oral gesturing. The increased maxillary angle in anger may suggest the threat of oral aggression, whilst tender lip rounding that transforms /i/ into [y], and j t j into [oe] may allude to a kiss. In the framework of the Darwinian evolutionary theory of emotions (1872) violent tension of the articulatory organs may be interpreted as a residue of the general muscular contraction preparatory to fighting. Heavy stresses might represent blows: the original meaning of Latin ictus 'accent' and Russian udarenie 'accent' is 'blow,' transfers based on the speaker's feeling of a kind of relation between the two concepts. Stressed syllables are, indeed, often accompanied by tapping and/or head nods (Azuma et al, 1981; Bolinger, 1983a; Heese, 1957). Oral gestures are grafted onto phono-types. Secondary messages are experienced as a 'manner of speaking'. 3. I have previously attempted to formulate the rules generating expressive phonetic distortions (see Fonagy, 1971). These rules are essentially based on the symptomatic-metonymic and the symbolic-
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metaphoric principles (see Jakobson, 1956: 58 — 82), and the principle of isomorphism of expression and content. In this paper I would like to present some speculations concerning the prerational mental bases of oral gestures which could be considered as vestiges of a preverbal mode of communication. Oral gesturing seems to have presuppositions analogous to the fundamental principles underlying magical practices, as defined by Frazer ([1890] 1964: 35 — 69). Speech organs may represent the whole body according to the pars pro toto principle of contagious or sympathetic magic. Advancing the tongue in joy or tenderness could thus reflect a physical or moral approach to the social partner, an attitude called entgegenkommend 'friendly,' lit.: 'coming to meet' in German. Phonetic allusions such as menace containing extreme mouthopening, or the friendly lip rounding, anticipating a kiss, could be based on the contact principle of sympathetic magic, though the contact between successive events is purely mental. Laryngeal closure followed by a violent outburst of air is a sign of discomfort in infants — Unlusteinsatz 'attack of discomfort' according to Gutzmann (1928) — and is typically frequent in angry speech. Laryngeal plosives might be thought of as a biological metaphor of the cough. The cough serves to eliminate, under high air pressure, harmful particles, preventing them from entering the lungs. By extension, additional (nonlinguistic) laryngeal plosives may serve as a sign of refusal and rejection. In terms of imitative magic: an irritating object, creating physical tension, is rejected, eliminated in the same way as are harmful particles. The violent contraction of the glottis and pharynx in hatred, producing a strangled voice, can be explained if we assume that the speaker identifies with the person who is the object of the hatred. In psychoanalytic terms: he introjects this person (Ferenczi, [1909] 1927: 9 — 61). In this context laryngeal and pharyngeal constriction could symbolize strangulation.
Prosodic gestures 4. Expressive prosodic speech acts offer particularly daring examples of extension of the principle of imitative magic. Glottal performances are interpreted spatially, as suggested, more than
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twenty-three centuries ago, by Aristoxenus: in terms of tone-movements. Thus, anguish might be reflected by a strongly narrowed pitch-range, suggesting a contraction of the whole body. The rigid melodic line in angry speech, interrupted at regular intervals by sudden rises in heavily stressed syllables my be interpreted as a tonal projection of struggle. The tonal image of anger contrasts markedly with the slowly undulating melodic line of tender approach which evokes the image of caressing movements. These assumptions were tested in a study using semantic differential ratings of synthesized variants of melodic patterns (I. Fonagy, J. Fonagy, and J. Sap, 1979). 5. Messages conveyed through articulatory or prosodic gesturing are pristine both in the manner of encoding, and in the content of the encoded messages. Gestures, as preserved in vocal style, belong to a phase of semiologic evolution preceding articulated1 arbitrary signs. They also remain on a lower level of semantic organization: even relatively sophisticated attitudinal messages conveyed by means of intonation do not reach the level of conceptual thinking. Signs are demotivated actions. The demotivation is accomplished in arbitrary linguistic signs, completely deprived of substance (de Saussure, [1916] 1976: 164). The principle of arbitrariness (de Saussure, [1916] 1976: 100—102) does not apply either to articulatory or to prosodic gesturing (Bolinger, 1978, 1983; Fonagy, 1956). Both are incompletely demotivated vocal performances. They still act in a similar way as performative utterances do (Austin, [1955] 1962: 8). The vocal expression of anger does not simply denote anger as does the sentence I am angry: it is a part of anger, an acting out of aggressive intentions. Consequently, the expression (i. e. the expression) of anger by means of a strangled voice or that of tenderness by means of caressing softness and an undulating melody is certainly not equivalent with expressions such as Ί am angry' or Ί like you' as suggested by Yorio (1973). The expressive power of live speech is essentially due to the incompleted transformation of real activity into purely semiotic acts. The distinction proposed by Bühler (1933: 49) between Sprachhandlung 'linguistic act' and Sprechakt 'speech act' is fully justified. 6. In order to avoid a misunderstanding which could easily arise, I should like to emphasize that the principles conveying emotive
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messages are probably universal, but the sound-patterns or the prosodic structures resulting from the application of these general rules are language dependent. The same transformation rule when applied to different inputs cannot have identical products. Laryngeal plosives as outputs have not the same effect in languages where they have a distinctive or demarcative function, as they do in languages where the 'hard attack' of vowels has no other function than expressing strong emotions. Expressions generated by procedures which are probably universal, have to be accommodated to the grammar of a particular language. Surprise tends to raise the tonal level both in French and in Hungarian. It often results in a rising intonation pattern in French owing to final stress; it cannot, however, produce such a curve in a baritonic language such as Hungarian (Fonagy, 1956).
Syntactic gesturing 7. A double encoding characterizes the concrete speech act on all levels. Irregularities of morpheme sequences conceal a double arrangement. The interpretation of expressive syntactic irregularities is in many ways similar to the decoding of more or less deviant expressive speech sounds. The irregular sequence needs to be traced back to the original, i. e. grammatical one, to identify the primary message of the sentence. The reconstructed grammatical sentence is now compared to the irregular sequence, in oder to identify the secondary message conveyed by means of expressive modifications of the grammatical word order. The principles governing the distortions of the grammatical order may again be symptomatic or symbolic; the two principles are, of course, not mutually exclusive. a) The most informative element of the message may be 'shot forward' ahead of the sentence, occasionally transgressing the rules of grammatical word order. Such transgressions may reflect the speaker's excitement, aiming at reducing tension as quickly as possible. The propeling of the noun phrase out of the sentence to the beginning of the utterance in informal French conversations, transforms the noun phrase into a kind of interjection which is
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reminiscent of the monolithic one-word sentences of an early phase of language acquisition (Fonagy, 1975). "Les enfants, suffit de les comprendre." (Children, enough to try to understand them.) Queneau, Zazie dans le metro. Languages endeavor to incorporate recurrent expressive transformations. The procedure of emotive 'dislocation' (Bally, 1921: 311) became a codified means of topicalization in French (Perrot and Louzoun, 1974). b) Word order may reflect the organization of objects in the outside world, especially in poetry (Spitzer, 1926: 146 ff). "Qu'il να, sto'ique, oü tu l'envoies." (That he goes, stoically, wherever you send him.) Victor Hugo, Trois ans apres. Moral isolation is being depicted in this example by means of the insertion of the adverbial complement which figures as an apposition, isolated by an initial and final pause of the other members of the sentence. c) An impulsive, nervous dismembering of the sentence may occur in angry speech, where syntactically and semantically related words are repeatedly separated. The sentence serves in such cases as an object of displacement, and is torn into shreds by the speaker, in the same way as he may occasionally tear into pieces a sheet of paper—using sentence or paper as substitutes for living beings. Such disarrangements are both symptomatic and symbolic. The fact that such interruptions are significantly more frequent in Verlaine's aggressive cycle of poems, the Invectives (15.8 per 100 words) than in the tender Bonne chanson (8.5 per 100 words) provides tentative support for the proposed interpretation of syntactic disruptions.
Semantic gesturing 8. Movements along the syntagmatic axis, the dimension of timetranspositions according to the terminology of Classical rhetorics — may be matched by virtual movements along the paradigmatic axis: the substitutions of Classical rhetorics. The replacement of an
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objectively adequate sign by a subjectively adequate one, a metaphor (Aristotle, Poetics 14576; Dubois, et al., 1970: 106-112; Fonagy, 1965; Ricoeur, 1975: 13-61). 2 The maxim of cooperative communication such as 'do not say what you believe to be false' or 'avoid obscurity of expression' prompt the hearer to search for some other meaning for blatantly false statements such as " boundless humility builds on my shoulders a snail shell, big and silent" (Ärpäd Toth, Erdöszel [Fringe of the forest]). Conversational maxims as defined by Grice (1975) clarify why the listener is compelled to impose his own interpretation on such statements, whereas there is no question of such further elaboration in the case of well-formed sentences (see Chomsky, 1965:112). Thus, there is a significant difference between the dynamics involved in the decoding of phonetic and syntactic deviances, on the one hand, and that of semantic deviances, on the other. The original expressions carrying the primary messages can and must be unambiguously identified on the phonetic and syntactic level, if the expression is to be understood. In the case of semantic substitutions, however, the reconstruction of the original term 3 constitutes the meaning of the metaphor. The wrong term used, the symbolizer,4 is in fact the only manifest, unambiguous element on which semantic elaboration can be based, given the context, and given the situation, and including knowledge founded on earlier experience. We have as yet little understanding of the rules underlying the interpretation of semantic transfers. Metaphors according to the theory outlined by Aristotle are erroneous statements which nevertheless enable the listener or the reader to infer the real meaning of the sentence, while interpreting the error as an implicit simile. The simile is expressed by means of the confusion of analogous items CPoetics 1457 b 7).5 This theory has been reformulated a number of times without the theory having fundamentally altered. Metaphors consist according to Weinrich (1967) of a conflict between a sign and its (verbal) context (see also Petöfi, 1969).This is, however, not a necessary condition (see Lehmann, 1975: 82). A metaphoric statement of the Hungarian poet, Endre Ady (1877 —1919) might serve as an example: "In the far distant depth of the time I was a woman, sturdy And loving." (Ha fejem lehajtom — 'If I bow my head.')
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The sentence itself is free from contradiction, but the statement violently contradicts reality inducing the reader to go beyond the sentence. The conflict between the components of a metaphoric sentence is a possible consequence of the inconsistency between statement and reality.6 The distinction between sentence and statement, between verbal and logical level is systematically applied in the description of tropes proposed by Pelc (1961). Levin's more recent work (1977) is a good illustration of the benefits of a multidimensional, linguistic, logical and esthetic analysis of metaphor. The distinction is not maintained either in the logically oriented study of Abraham (1975), or in the linguistic analysis of metaphor in terms of feature extinction (Katz, 1969; Konrad, 1939; Müller 1887, Chap 8), of selectional restriction violation (Matthews, 1971), of semantic extension (Bickerton, 1969) or transfer features (Sanders, 1973). The limitations of a strictly linguistic analysis of metaphor 7 are particularly apparent in Bickerton's (1969) theory. He sees in a previous, more or less arbitrary, feature assignment to a word a necessary condition to its metaphoric use. Thus, the attribute 'hardness' attached to iron marks the word as a potential metaphor, and gives birth to iron will. In other cases the extension would be deviant, as for instance in that of steel will. Matthews (1971) pinpointed the circularity of Bickerton's argument, since our judgment of the markedness of iron is based on metaphoric expressions such as iron will. The paradoxical statement that metaphor is a linguistic rule of rule transgression, or the result of individual creativity conditioned by the linguistic system (Lehmann, 1975: 105) may arise out of the confusion of the two meanings of language and German Sprache. They denote both concepts thoroughly distinguished by de Saussure: langue, the systen of a given language, and langage 'language ability' considered as "multiforme et heteroclite, ά cheval sur plusieurs domaines" as well as individual speech acts (Lehmann, 1975: 112). Expressive distortions, inherent to speech acts are governed by paralinguistic rules which could be considered as protolinguistic from an evolutionary point of view. Semantic transfers could be viewed in this perspective as a playful reproduction of errors which necessarily occur in an early phase of mental development (see Werner, 1933). 9. In previous papers I attempted to trace a parallel between certain types of semantic transfers, on the one hand, early mental processing,
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and certain types of mental regression, on the other (Fonagy, 1972, 1978,1982). Some examples may illustrate such parallel trends. a) Substitution of a sensory concept for a nonsensory one; we were talking about children's books which might be worth republishing because children like them: "Es ha nem edes?" (And if it is not sweet?). b) Confusion of sensory domains: "Na du muß doch die Augen aufmachen, sonst weißte nicht, was ich gesagt hab!" (Well, you have to open your eyes, otherwise you won't know what I have said) (E. and G. Scupin, 1910: 134, as quoted by Werner, 1933: 73). c) Animation, personification of inert objects. Projective reality testing (Ferenczi, 1927, vol. 1: 73). The father: "Hagyd mär azt a trombität!" (Put down your trumpet!). The son (4;1): " Mer? Färadt?" (Why? Is it tired?). Animation of certain objects frequently underlies phobic fears. A three-year-old Hungarian girl developed a phobic fear of an open black umbrella. Some five years later she explained to her parents that the open umbrella represented the wide open mouth of a devil. d) Subjective, ego-centered analysis: a Hungarian girl (1;2) starting from gomb 'button' produced one-word sentences such as [pomp], [mompu] which could refer to anything that was round and could be taken into the mouth: a ball, the big toe, etc. e) Impressionistic analysis, unstable size-constancy. Helmholtz (1856: 623) related in one of his major works that as a child, looking out of the window he believed that the people walking in the street were tiny puppets, and remembered asking his mother to give him the steeple of a distant church. f) Identification of form and content, the container and the contained. A ten-year-old girl noticed a hole in her father's sock: "Lukas läbi." (Hole in the foot). A two-year-old girl pointing to her mother's dressing-gown: "Anyi." (Mummy). g) The producer identified with the product: We were playing twenty-questions with the children. My daughter was thinking of a book but my son (six years old) was unable to guess what the object was. When he was finally told what she was thinking of, he indignantly shouted: "A könyv el, mer aki irta az is el." (A book is
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alive because the man who wrote it is alive). (Since he was told it was an inanimate object). h) Identification of the representation with the object represented: "Most olyat rajzolj, amelyik csip." (Now draw one, i. e. a mosquito, that bites), (a 2;8-year-old boy). A three-year-old Hungarian girl asked looking at a family picture: "Meg el?" (Is she still alive?) pointing at her grandmother. As she was told that she was dead, she asked: "Belehalt a kepbe?" (She died in the picture?). i) Identification of the whole object with a part of it: "tick-tack" referred in one of the first one-word sentences of a ten-month-old Hungarian girl to the chain of the watch as well as to the watch itself. j) Substitution of the specific for the general: a little girl of 2;3 calls (shortly after the summer vacation) every pool "Balaton" (the name of a big lake in Hungary she had visited). Similarly, quantitative transfers such as hyperbole can be interpreted as objects viewed through children's eyes, and as literary forms of narcissistic childish exaggeration ("My Teddy-bear is the biggest."). 10. Semantic transfers are cases of controlled, playful regressions. Transformations evoking pristine mental processing are demotivated, decathected (i. e. the negative of 'cathexis — cathected'). Remotivation of such processes results in delusions in cases of psychotic disturbances. The patients seem to regress to a period where the rationalizing spell resembles, like, as z/have not yet come into being (see Searles, 1965: 560 - 583).8 Daniel Gottlieb Schreber, Presiding Judge over the Saxon Appeal Court in Dresden, had to give up his career, and enter an asylum, because he expressed ideas quite similar to those written by the Hungarian poet Ady in the verses quoted above. Schreber really believed that he had been transformed into a woman and, being the future mistress of the Divinity, he would be able to save the world from a cataclysm (see Freud, G.W., Vol. 8: 230-320; S.E., Vol. 12: 12 — 80). The poet's fantasy, demotivated and transposed into the past, did not have such dramatic consequences. Delusions characteristic of psychotic megalomania could be considered as revitalized hyperboles. "I sang a song," said a patient of Istvän Hollos, a forty-eight-year-old typographer, "and all the
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printing shops of the world united, then came ham, bacon and goulash in tremendous quantities" (Hollos and Ferenczi, 1922:13). 11. Through a still mysterious metamorphosis, deeply rooted misconceptions may become prodigious tools of discovery. Metaphor starts with the rejection of an existing term, and a ready-made concept: the speaker has to face undomesticated reality. For some seconds he regresses to an early phase of mental development, to the source of language and conceptual thinking. At this stage there is no clear-cut division line separating conscious, preconscious and unconscious mental activities. This enables the speaker to go beyond the domain of conscious knowledge. In making metaphors, Greek and Roman grammarians distinguished phonetic features they totally ignored, designating them by means of absurd but nevertheless appropriate terms. They considered for instance velar vowels as dark, and palatals as light, without knowing that the tongue points upwards and outwards (toward light) when articulating 'light' vowels; and backwards and downwards (towards the dark region) when pronouncing 'dark' vowels. French as well as Russian or Hungarian grammarians called the palatal or palatalized consonants moistened, without knowing that the metaphor is based on the sensation of an increased surface of contact between the moist tongue and the moist palate (Fonagy, 1980). Kempelen (1791: 225-227), who designed and constructed the first synthesizer, indignantly rejected such terms as absurd. In spite of their apparent absurdity, these terms nevertheless enabled authors and readers to communicate effectively about matters largely unknown: so to speak behind their back. The use of scientific metaphors could be considered as a kind of controlled delusion.
Grammatical Transfers 12. Grammatical metaphors can similarly be retraced to some basic forms of pristine mental processing. The transformations of adverbs of place into adverbs of time or that of adverbs of time into adverbs of manner is a universal phenomenon (Cassirer, [1924] 1955: 207). At the same time it reproduces a paleological conception of time and causality (Arieti, 1955). In the language of dreams, both chrono-
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logical and causal relationships are usually translated into spatial order (Freud, G. W., Vol. 2 - 3 ; S.E., Vol. 4 - 5 , Chap. 6). The semantic structure pf possessive constructions (genitive) in most European languages still reflects a paleological identification of such categories as (a) possession, (b) parental relationship, (c) relationship of love (Lady Chatter ley's Lover), (d) social dependence or dominance {Lord of the Flies), (e) the relationship of the part and the whole ('the back of the book'), (f) relation between producer and product ('the hen's egg'), (g) a causal relationship ('the shadow of the chimney,' 'the echo of the shot' (Fonagy, 1978). All these different meanings are traces of recurrent grammatical metaphors based on playful regression to paleological mental processing. The assumption of the universality of this form of ideation may help us to understand the striking similarity between the semantic structure of corresponding grammatical as well as lexical morphemes in unrelated languages. 13. Transfers of word categories are halfway between lexical and grammatical metaphors (Fonagy, 1983). Nominalization of adjectives and verbs could be considered as a demotivated allegorizing, and allegories as half-demotivated myths. In homeric poetry the frontier between myth and allegory is fleeting. In the fourth song of the Illiad (w. 439—443) we see side by the allegories Deimos 'Horror,' Phobos 'Fear' and the divinities Pallas Athene, Ares and Eris. (Let us add that the names Ares and Eris are meaningful: they denote 'homicide' and 'battle'). In the nineteenth song Ate figures as an allegory in the line 88, and as a goddess, the daughter of Zeus, in the line 91 (see Fränkel, 1921). Since abstract nouns such as horror, happiness, darkness or superego are potential myths and frozen allegories, giving substance even to 'absence' or 'disappearance,' no wonder that they revive in the form of delusion or phobic fear: "Jon α sötet." (Darkness comes), said a two-year-old Hungarian girl; "Ne gyere, Sötet." (Don't come, Darkness).
Preverbal communication in the present (The assumptions revisited) 14. The assumptions illustrated in this paper are, of course, inconclusive, unless they are tested and corroborated by the analysis of larger samples representing unrelated languages of different types.
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Few systematic investigations have been carried out as yet on emotive articulatory distortions. The Terminologie Project of the Prague Linguistic Circle (see Travaux du Cercle Linguistique de Prague 4 -1931, Supplements, 309 — 326) qualified variants as "nonlinguistique." Laziczius (1935: 204) was the first structural linguist who attributed a linguistic status to combinatory and free variants. In his paper on emotive language, Stankiewicz (1964: 249) quotes convincing examples illustrating the language dependence of variants: palatalization of consonants carries a pejorative meaning in South-Eastern Yiddish; it is associated, however, with an affectionate attitude in Basque, where palatalization functions as a diminutive morpheme. Further examples could be easily provided. Thus, emotive vowel lenghtening is limited to stressed syllables in German or Hungarian, but not in Rumanian. The emphatic lengthening of the first consonant is linked with emphatic stress in Modern French, and was probably unknown before the second half of the nineteenth century (Fonagy, 1956). Such examples do not imply that emotive variation of consonants and vowels should be fortuitous — unless we, unduly, consider the concepts 'conventional' and 'arbitrary' as synonyms. Individual languages are free to select among the products of emotive variation, based on paralinguistic principles, and to assimilate such products to a given linguistic structure. Even such homonyms as pejorative and affectionate palatalization might be traced back to iconic procedures: to salivation due to disgust, on the one hand, and to the imitation of infantile palatalized speech, on the other. Little attention has been given to expressive oral mimetics in children's preverbal utterances or early verbal expressions. The correlation between discomfort and laryngeal constriction, smooth vibration of the vocal chords and a pleasant mood, as observed by Gutzmann (1928), is also manifest in the speech of Hungarian and French infants (Fonagy, 1983). The association of pleasant mood with the advancing and raising of the tongue, and that of negative attitudes with the withdrawal of the tongue, could be equally tested. Such correlations have to be verified for other unrelated languages, in children and adults. In order to falsify the assumption of the iconic character of such variations we had to point out languages where anger and hatred were associated with smooth articulation; tenderness with laryngeal and pharyngeal constriction,
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positive attitudes with backward movement, negative attitudes with forward movement of the tongue. We have some evidence concerning the iconicity of prosodic features (Bolinger, 1978; Cruttenden, 1980; Fonagy, 1981; Hermann, 1942; Huttar, 1967). Sentence stress and intonation can be considered as language dependent motivated (iconic) signs; i. e. the universal tendencies underlying stress distribution and intonation, integrated into related or unrelated languages, produce more or less divergent but analogous surface structures. We have less direct evidence on the iconicity of emotive distortions on the syntactic level. Conversations recorded in the framework of discourse analysis are rarely emotive. There is certainly more emotion in the recorded speech of children; it seems, however, that linguists who analyzed the recordings were more interested in syntactic evolution than in syntactic distortions. We are still largely dependent on non-systematic observations (Bally, 1905, [1911] 1921) and, essentially, on indirect evidence: speech as reflected in plays and novels, on the one hand; the reconstruction of emotive speech by means of diachronic analysis of syntactic changes, on the other hand. (See for instance Richter, 1919-1920). Ancient rhetoric constitutes a highly precious source of knowledge, as far as Classical languages are concerned. The theory of figures recovers the domain of expressive syntactic distortions; the theory of tropes that of expressive semantic irregularities (see Lausberg, 1960). We are equally indebted to Sanskrit poetics (Gerow, 1971; Jenner, 1968). In spite of the divergencies in imagery between different literary currents, analogies are still more conspicuous. Our first assumption, once tested and corroborated, could lend some likelihood to the second assumption: iconic signs presumably precede arbitrary ones. Iconicity represents a transitory phase in the process of gradual demotivation of real (nonverbal) acts which have to be deprived of substance in order to become transparent signs of the denoted objects and events. In the iconic sign the denoted events or objects are still present in some way. The expression of anger by means of the forceful contraction of the articulatory muscles and a 'strangled' voice, is a part of anger, and not the simple denotation of anger. It is, at the same time, both much more and much less than the word anger, based on conceptual analysis of emotive attitudes.
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Similarly, metaphors represent a more primitive state of mental elaboration as compared to nonambiguous verbal representation of scientific concepts. Metaphors reproduce pristine forms of mental processing (Fonagy, 1982). Such voluntary mental regressions enable the speaker to express still unsettled mental content. The survival of pristine modes of communication in present-day speech is by no means accidental. Reducing live speech to a sequence of phonemes —to dead letters—would lead us to renounce the acting-out of emotive mental contents. Dispensing with semantic transfers would be tantamount to freezing our present conceptual network, and renouncing the expression and stabilization of preconscious mental contents.
Conclusion At the end of the article the reader may wonder what bearing the paper has upon the conference theme. The important issue of language-origin may be, I think, most conveniently and confidently approached from the perspective of the present day. Comparative analysis of expressive articulatory distortions and expressive prosodic features in a great number of unrelated languages could furnish data concerning the preverbal gesture language and explain the manner of its transformation into segmental and prosodic linguistic signs. Similarly, the study of paralinguistic tendencies governing expressive syntactic deviations could be helpful in reconstructing the syntax of this hypothesized proto-language. Finally, semantic 'gesturing,' i. e. lexical and grammatical transfers, could offer some insight into preverbal semantics. Notes 1. The word is used in the sense of 'twofold articulation/ double articulation' of sentences into morphemes, and morphemes into phonemes, according to Martinet (1967: 13 — 15); 'articulatio prima et secunda,' in the terms of medieval grammatical theory (see Jakobson and Waugh, 1979: 177). 2. In an earlier paper I attempted to outline a system of expressive semantic deviances (Fonagy, 1971). 3. Sensum proprium (Quintilianus, Institutio Oratoria, 8, 6, 4); upameya 'subject' in Sanskrit poetics (see Gerow, 1971: 55 — 58); sens spirituel (Fontanier, [1821] 1968: 5 8 - 5 9 ) ; the tenor according to Richards (1936: 7); gens reel (Genette, 1966: 213).
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4. Sensur improprium (Quintiiianus, I.O., 8, 6, 4) upamäna (Gerow, 1971: 55 — 58); sens litteral (Fontanier, [1821] 1968: 58-59); vehicle (Richards, 1936: 7); sens virtuel (Genette, 1966: 213). 5. In Sanskrit poetics the dichotomy of simile versus metaphor is replaced by a more differentiated system of lexical figures, such as atisadjokti, the expression of an analogy by use of the conditional; utpreksä where the symbolized is considered as the mirror image of the symbolizer; smarana, expression of the analogy in the form of a naive error, etc. (see Jenner, 1968). 6. A logical predicate is assigned wrongly to an object which is outside the conceptual sphere of this predicate (Lehmann, 1975: 74, 108). 7. Drange (1966) considers metaphor an unthinkable proposition. According to Price (1974) it cannot be treated in a grammatical framework. 8. The semantic evolution of the comparison-operator reflects the mental process of demotivation. The conjunction as from ealswa originally implied the identification of the compared terms (eal 'all,' swa 'sc'). The comparative adverb like derived from lie 'body' suggesting a physical identity, in the same way as Old High German gilih (cf. German Leiche 'corpse,' and gleich 'equal' as well as 'similar.' 9. The mode of functioning of the non-dominant right hemisphere appears to be related to the metaphoric mode of mental processing. It is characterized by holistic pattern recognition (Levy-Agresti and Sperry, 1968; Nebes, 1971; Spencer and Ulatovska,1979), effortless, spontaneous analysis (Dimond and Beaumont, 1974: 71), formation of concepts without the necessity of detailed analysis (Nebes, 1974), preference for pictorial, sensorial representations (Gibson et al., 1970; Patterson, 1979; Seamon and Gazzaniga, 1973) and multimodal, diffuse perception (Semmes, 1968; and see also Jakobson and Waugh, 1979: 28 — 35). Dixon (1981) considers the right hemisphere as the probable neurological base of primary process thinking. The metaphoric mode of processing is explicitly associated with the right hemisphere mode of processing by McKinnon (1979).
References Abraham, Werner 1975 A Linguistic Approach to Metaphor. Publications on metaphor 1. Lisse: De Ridder. Ady, Endre 1930 Összes Versei. (Collected Poems). Budapest: Atheneum. Arieti, Silvano 1955 Interpretation of Schizophrenia. New York: Brunner. Aristotle 1954 Rhetoric and Poetics. W. Rhys (ed.), A. Roberts (transl.). New York: Random Aristoxenus 1868 Harmonische Fragmente. P. Marquand (ed.). Berlin: Weidmann. Austin, John [1955] 1962 How To Do Things With Words. Oxford: Clarendon.
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Azuma, Junichi (et al.). 1981 The visual effect of the speaker's gestures on auditory comprehension. Papers of the First International FLEAT Conference. 1 — 24. Tokyo. Bally, Charles 1905 Precis de Stylistique. Geneve: Eggismann. Bally, Charles [1911] 1921 Traite de Stylistique Frangaise. Vol. 1 - 2 . Paris: Klincksieck. Bickerton, Derek 1969 Prolegomena to a linguistic theory of metaphor. Foundations of Language 5. 34 — 52. Bolinger, Dwight 1978 Intonation accross languages. In Joseph H. Greenberg (etal.) (eds.), Universals of Human Language. 471 — 542. Stanford: University Press. 1983a Intonation and gesture. American Speech 58. 156 — 174. 1985 The inherent iconism of intonation. In John Haiman (ed.), Iconicity in Syntax. Proceedings of a Symposium on Iconicity in Syntax, Stanford, June 24 — 26, 1983. 97 — 108. Amsterdam, etc.: Benjamins. Bühler, Karl 1933 Sprachtheorie. Jena: Fischer. Cassirer, Ernst [1924] 1955 The philosophy of Symbolic Forms. Vol. 1. Language. New Haven: Yale University Press. Chomsky, Noam 1965 Aspects of the Theory of Syntax. Cambridge, Mass.: M.I.T. Cruttenden, Alan 1980 Falls and rises: Meanings and universals. Journal of Linguistics 17. 77-91. Culioli, Antoine 1970 Unpublished university lecture. Darwin, Charles 1872 The Expression of Emotions in Man and Animals. London: Murray. Dimond, Stuart J. and Graham Beaumont (eds.) 1974 Hemisphere Function in the Human Brain. London: Elek. Dixon, Norman 1981 Preconscious Processing. Chicester: Wiley. Drange, Theodore 1966 Type Crossing. The Hague: Mouton. Dubois, Jean (etal.) 1970 Rhetorique Generale. Paris: Larousse. Ferenczi, Sandor [1909] 1927 Bausteine zur Psychoanalyse. Vol. 1—2. Leipzig, etc.: Internationaler Psychoanalytischer Verlag. Fodor, Jerry A. and Marrill P. Garrett 1966 Some reflections on competence and performance. In John Lyons and Robin J. Wales (eds.), Psycholinguistic Papers. 165 — 179. Edinburgh: University Press. Fonagy, Ivan 1956 Ueber die Eigenart des sprachlichen Zeichens. Lingua 6. 67 — 88.
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Form and function of poetic language. Diogenes 51. 72 — 110. Double coding in speech. Semiotica 3. 189-222. Demotivation et remotivation. Poetique 11. 413—431. Languages within language. In William McCormack and Stephen A. Wurm (eds.), Approaches to Language. 79 — 134. The Hague: Mouton. 1980 La Metaphore en Phonetique. Ottawa: Didier. 1981 Emotions, voice and music. In J. Sundberg (ed.), Research Aspects on Singing. Publications by the Royal Swedish Academy of Music 33. 51-79 1982 He is only joking. In Ferenc Kiefer (ed.), Hungarian Contributions to General Linguistics. 31 — 108. Amsterdam: Benjamins. 1983 Word class transfers in poetry and prose. Language and Style 16. 227-240. Fonagy, Ivan, Judith Fonagy and Jacques Sap 1979 A la recherche des traits pertinents prosodiques du fran?ais. Phonetica 36. 1 - 2 0 . Fonagy, Ivan, Mun-Hi Han and Pela Simon 1983 Oral mimetics in two unrelated languages. In Peter Winkler (ed.), Investigations of the Speech Process. Quantitative Linguistics 19. 103 — 123. Bochum: Brockmeyer. Fontanier, Pierre [1830] 1968 Les Figures du Discourse. Paris: Flammarion. Fränkel, Hermann 1921 Die homerischen Gleichnisse. Göttingen: Hogrefe. Frazer, James [1890] 1964 The New Golden Bough. New York: Mentor. Freud, Sigmund 1940—1968 Gesammelte Werke ( = G.W.). Vols. 1 - 1 7 . London: Imago. 1968-1974 The Standard Edition of the Complete Psychological Works. ( = S. E.). Vols. 1—24. London: Hogarth. Genette, Gerard 1970 Figures Vol. 1. Paris: Seuil. Gerow, Edwin 1971 A Glossary of Indian Figures of Speech. The Hague: Mouton. Gibson, A. E. (etal.) 1970 Hemisphere differences as reflected by reaction time. Federal Proceedings. Vol. 29. 658. Grice, Herbert P. [1968] 1975 Logic and conversation. In Peter Cole and Jerry Morgan (eds.), Syntax and Semantics. Vol. 3. Speech Acts. 41 — 58. New York: Academic Press. Gutzmann, Hermann 1928 Physiologie der Stimme. Braunschweig: Viehweg. Heese, Georg 1957 Akzente und Begleitgebärden. Sprachforum 2. 274-285. Helmholtz, Hermann 1856 Handbuch der Physiologischen Optik. Leipzig: Teubner.
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Hermann, Eduard 1942 Probleme der Frage. Nachrichten der Akademie der Wissenschaften. Phil. Hist.Klasse, 3 und 4. (entire issue). Hollos, Istvan and Sandor Ferenczi 1922 Die Psychonalyse der Paralytischen Geisteszerrüttungen. Leipzig: Internationaler Psychoanalytischer Verlag. Hugo, Victor [1856] 1967Lei Contemplations. La Pleiade, Oeuvres Poetiques, Vol. 2. Paris: Gallimard. Huttar, George L. 1967 Some Relations Between Emotions and the Prosodic Parameters of Speech. Speech Communication Research Laborytory Monographs 1. Santa Barbara. Jakobson, Roman 1956 Two aspects of language. In Roman Jakobson and Morris Halle (eds.), Fundamentals of Language. 55 — 87. The Hague: Mouton. Jakobson, Roman and Linda Waugh 1979 The Sound Shape of Language. Bloomington: Indiana University Press. Jenner, Georg 1968 Die Poetischen Figuren der Inder von Bhämaha bis Mammata. Hamburg: Appel. Katz, Jerrold J. 1966 The Philosophy of Language. New York: Harper and Row. Kempelen, Wolfgang 1791 Mechanismus der Menschlichen Sprache. Wien: Degen. Konrad, Heinz 1939 Etude sur la Metaphore. Paris: Vrin. Lausberg, Heinrich 1960 Handbuch der Literarischen Rhetorik. München: Hueber. Laziczius, Julius von 1935 Probleme der Phonologie. Ungarische Jahrbücher 15, 495 — 511. (Reprinted in Thomas A. Sebeok (ed.), Selected Writings. 38 — 58. The Hague: Mouton). Lehmann, Α. 1975 Metapher und Semantische Beschreibung. Glessen: Schmitz. Levin, Samuel R. 1978 The Semantics of Metaphor. Baltimore etc.: Johns Hopkins. Levy-Agresti, Jerry and Roger W. Sperry 1968 Differential perceptual capacties in major and minor hemispheres. Proceedings of the U.S. National Academy of Sciences 61. 1151. McKinnon, John 1979 Two semantic forms. Psychoanalysis and Contemporary Thought 2. 25-76. Martinet, Andre 1967 Elements de Linguistique Generale. Paris: Colin. Matthews, Robert J. 1971 Concerning a 'linguistic theory' of metaphor. Foundations of Language 7. 413-425.
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Müller, Max 1887 The Science of Thought. New York: Scribner. Nebes, Robert D. 1971 Superiority of the minor hemisphere in commisurotomized man for the perception of part-whole relations. Cortex 1. 33—349. Nebes, Robert D. 1971 Hemispheric specialization in commisurotomized man. Psychological Bulletin 81. 1 - 1 4 . Patterson, Karolyn E. 1979 What is right with 'deep' dyslexis patients? Brain and Language 8. 111-129. Pelc, Jerzy 1981 Semantic functions as applied to the analysis of the concept of metaphor. In Donald Lavie (etal.) (eds.), Poetics. 305 — 340. Warszawa: Panstwowe Wydawnietotwo Naukowe. Perrot, Jean and Myriam Louzoun 1974 Message et apport d'information: A la recherche des structures. Langue Frangaise 21. 122-135. Petöfi, Janos S. [1967] 1969 On the structural analysis and typology of poetic images. In Ferenc Kiefer and Jänos S. Petöfi (eds.), Studies in Syntax and Semantics. 187-229. Dordrecht: Reidel. Price, J.T. 1974 Linguistic competence and metaphorical use. Foundations of language 11. 253-256. Project de terminologie phonologique standardisee 1931 Supplement to Travaux du Cercle Linguistique de Prague 4. 309 — 326. Queneau, Raymond 1953 Zazie dans le Metro. Paris: Gallimard. Quintilianus, M.F. 1907—1935 Institutio Oratorio. A. Radermacher (ed.). Leipzig: Teubner. Richards, Ivor A. 1936 The Philosophy of Rhetoric. Oxford: University Press. Richter, Elise 1919 —1920Grundfragen der Wortstellung. Zeitschrift fur Romanische Philologie 40. 9 - 6 1 . Ricoeur, Paul 1975 La Metaphore Vive. Paris: Seuil. Sanders, Robert R. 1973 Aspects of figurative language. Linguistics 96. 56 — 100. Saussure, Ferdinand de [1916] 1976 Cours de Linguistique Generale. Critical edition by Tullio de Mauro. Paris: Payot. Scupin, E. and G. Scupin 1910 Bubi im Vierten bis Sechsten Lebensjahr.λ,ύτρύξ;. Grieben. Seamon, John G. and Michael S. Gazzaniga 1973 Coding strategies and cerebral laterality effects. Cognitive Psychology 5. 249-256.
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Searles, Harold F. 1965 Collected Papers on Schizophrenia. London: Hogarth. Semmes, J. 1968 Hemisphere specialization. Neuropsychologie 6. 11—26. Spencer Day, Patricia and Hanna R. Ulatovska 1979 Perception, cognition and linguistic development after early hemispherectomy. Brain and Language 7. 17 — 33. Spitzer, Leo 1926 Stilstudien. Vol. 1. Sprachstile. München: Hueber. Stankiewicz, Edward 1964 Problems of emotive language. In Thomas A Sebeok (etal.) (eds.), Approaches to Language. 239 — 276. The Hague: Mouton. Toth, Arpad 1962 Összes Versei, Versforditasai es Novellai. (Complete Edition of his Poetic Works, Translations and Short Stories). Budapest: Szepirodalmi Könyvkiado. Trojan, Felix 1952 Der Ausdruck der Sprachstimme. Eine phonetische Lautstilistik. Wien, etc.: Maudrich. Trojan, Felix 1975 Biophonetik. Wien, Bibliographisches Institut. Verlaine, Paul 1962 Oeuvres Poetiques. Paris: Gallimard, Bibliotheque de la Pleiade. Watt, William S. 1970 On two hypotheses concerning psycholinguisitcs.In J. Η. Hayes (ed.),Cognition and Development of Language. 137—220. New York: Wiley. Weinrich, Harald 1967 Semantik der Metapher. Folia Linguistica 1. 3 — 17. Werner, Heinz 1933 Einfuhrung in die Entwicklungspsychologie. Leipzig. Ambrosius. Yorio, Carlos A. 1973 The generative process of intonation. Linguistics 97. I l l —123.
On linguistic territoriality, iconicity and language evolution Marge E. Landsberg
Abstract The present paper presents a semiotic model of human language as a signalling system. Thus vocal and/or visual sign-using behaviors are considered as display mechanisms within their territorial matrices. Because communication is a social process, the most productive course of study concerns the nature of the information which can be inserted into social actions by these displays, selective attention being paid to particularly useful signals. The unequivocal definition of territory plausibly accounts for the enduring profusion of territorial aspects of human utterances. This system probably originated in primordial vocabularies of kinesics and proxemics, with some prelinguistic ostensive gestures directing attention to objects in space. As the distinctions among such phenomena are initially understood as vocal alternatives to visual ostension, they are obviously of paramount importance for our knowledge and understanding of glottogenesis. Reflecting nonlinguistic reality, linguistic iconicity offers perceptible evidence of such alternative forms. These may be found on all levels: morphological, phonological, syntactic and semantic. As any theory of the evolution of language must also take account of the evolution of the cerebral hemispheres and their interactions, the place of the icon as a necessary link in this process is discussed. Two pivotal points of interest in any discussion of glottogenesis are the transition of animal to human awareness, and the transition of limbic to neocortical control over vocal signalling. Awareness of self, of others, of environment, a sine qua non for communication, gives immediate rise to the problem of 'living space' or 'territory.' In order to protect themselves and their living space, in short, in order to survive, all but the most primitive forms of life have
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developed a repertoire of vocal and/or visual displays, to safeguard this personal territory. Territorial definition and territorial protection are, therefore, very deeply ingrained animal survival instincts, engendering a mass of fascinating phenomena, both vocal and nonvocal. The establishment of a territory allows animals to carry out particular aspects of their behavior in suitable surroundings and in comparative safety. As a point of special interest it might be noted here that it has been observed by Landenberger (1973: 552) that "visual or vocal displays have evolved in some species so that physical conflict may be minimal or absent." This would somewhat contradict the regular aggressional connotation of territoriality, and as such may constitute a selective adaptive advantage that carries important survival benefits. It may be worthwhile remembering this point when discussing linguistic territoriality, and one might wish to pause and ponder its human implications. Man's territorial stratification is three-dimensional and coordinate, with himself at the center. This stratification is expressed in displays (i. e. stylized behaviors by which an animal provides certain specific information to members of its own or other species — usually in the form of visual or auditory, though sometimes also olfactory, signals). Virtually all animals use displays to some extent to indicate theit intent. Territorial displays must of course not necessarily be confined to courtship, mating, breeding or defense. The study of display mechanisms is primarily concerned with the motivational states and the subsequent behavior of their users, the transmitted displays informing the recipient that the communicator is in that state and is apt to behave thus. The recipient thus should be able to predict, at least in part, the activities of the communicator, and plan his own reactions accordingly. We can see and appreciate the intrinsic survival value of such a communication system. Because communication is a social process, the most productive course of study concerns the nature of the information which can be inserted into social interactions by displays. In the present study human language is considered from an anthropological-semiotic viewpoint; that is, as a territorial display system, serving as a spacing and signalling mechanism. The orientation of an animal can be viewed as a process of communication with its surroundings, in the sense that signals from the environment trigger behavior responses. As in communication
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between animals, selective attention is paid to particularly useful signals. Descriptions of the displays related to territorial definition and protection fall naturally within this group. As human language within its territorial matrix can be seen as a string of visual-vocal displays, the present paper is mainly concerned with a consideration of the territorial context of these displays and the phenomena it engenders. When discussing human awareness and territoriality, it may be observed, as pointed out by Lyons (1979: 718), that spatial organization is of central importance in human cognition (cf. Miller and Johnson-Laird, 1976: 375ff). This is so to such an extent that in most languages today, temporal terms are patently (i.e. historically) derived from locative expressions. Thus, for instance, Traugott (1976) points out that "nearly every preposition or particle that is locative in English is also temporal." Lyons (1979: 718) further notes that "The spatialization of time is so obvious and pervasive a phenomenon in the grammatical and lexical structure of so many of the world's languages that it has been frequently noted. Moreover, by virtue of the interdependence of time and distance (in that what is further away takes longer to reach) there is a direct correlation between temporal and spatial remoteness." We shall see later on that there also exists a direct correlation between psychological and spatial remoteness, and that this may find its expression in linguistic phenomena. Indeed, concepts of space and time are productive of many kinds of linguistic activity. Space involves orientation, measurement of lengths and weights, consciousness of state, dimension, shape, size and number. References found in the systems of terms for such concepts are clearly based on the use of space, and hence tend to reflect it iconically in one way or the other, as we shall see below. Not only does time similarly involve location and change but as we can see upon some reflection and introspection, we adhere to a totally spatial concept of time (cf. Landsberg, 1984d). As the general rationalist approach to semantics gives a sadly inadequate account of language as a semiotic system,1 relating utterances to their spatiotemporal context is considered much more fruitful and realistic. As pointed out above, egocentric employ of the space concept places ego at the center of the universe, from where it generates a threedimensional coordinate system. The unequivocal definition of static/dynamic physical or living space (terri-
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tory), a sine qua non for special survival, plausibly accounts for the enduring profusion of territorial aspects of human utterances. This is an indelible legacy of early deictic awareness, which in its most primitive form can be summed up as I-here-now. This deictic system probably originated in ancient vocabularies of kinesics and proxemics, with some prelinguistic ostensive gestures, facial expressions, or other semantic motor acts, directing attention to objects and their location, state and dimension in space. As the distinctions among such phenomena are initially understood as vocal alternatives to visual (gestural, facial, bodily) ostension, they are clearly of paramount importance for our knowledge and understanding of glottogenesis. A good question to ask here is, what is meant by "an enduring profusion of territorial aspects of human utterances," or how do our verbal displays today signal territorial perception and intent? I have dealt above with the concept of "territory" and "display". We must now consider the linguistic aspects or, in other words, how are our utterances semiotically related to their spatiotemporal contexts? To put it even more simply and directly, are there visual or auditory, nonlinguistic aspects to certain elements in our language? This indeeed seems to be the case, as I shall show below, and far more widespread than was hitherto suspected. The most amazing and conspicuous fact that emerges from our data is the overt iconic2 character of these phenomena. This of course raises a host of other questions, such as the role of iconicity in glottogenesis (cf. Landsberg, 1983c), the origin and evolution of human language, and the role of iconicity in human evolution, which I shall deal with below. Suffice it to note here that for such a principle to have been maintained so steadfastly, demonstrates its intrinsic importance. Indeed, it may well turn out to be a universal and defining (design) feature of human language. For although it may be so that in essence human language is neither purely arbitrary nor purely iconic, it appears for a much larger part than was suspected hitherto motivated by paralinguistic (i.e. physiological and psychological) principles. It is the "glossodynamic" aspect, or the "psychological phase of linguistics, which deals with motivation, either on the sound level, meaning level, or grammar level" (Roback, 1954: 429) that the present paper is mainly concerned with. As we shall see, there exists also a very important morphological level. Indeed, iconicity pervades our language on all dimensions: morphological, phono-
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logical, syntactic, and semantic, so that we can speak of morphological, phonological, syntactic, and semantic iconicity (cf. Landsberg, 1980c, 1981b, 1983c). In morphological iconicity, the structural shape of linguistic items reflects either shortness (so that our vocal displays signal proximity, smallness, familiarity, insignificance, etc., as for instance in truncations, hypocoristics, or diminutives, etc.; or length (to signal distance, increase, importance, etc.), as for instance in preterites, plurals obliques, comparatives, augmentation (e. g. reduplication, repetition), etc. 3 In phonological iconicity, the sound-structure variables manifest such feature changes as vowel modifications. As pointed out by Wescott (1971: 421), "among vowels the three chief axes of polarity are front vs. back, high vs. low, and spread vs. round." Wescott's example is pipi vs. caca signalling both size and distance polarity. I should like to point at the ubiquitous [i] sound (to signal proximity, connexion, belonging, possession, smallness, familiarity, intimacy, closeness, etc.), with the just as inescapable opposite [a] paradigms serving to signal spatiotemporal or psychological distance, or bigness (in size, amount, number degree, range, scale, etc.); consonant modifications (laterals and apicals connoting smallness, labials and velars connoting or signalling bigness); (note that the lateral consonants occurring in English are represented phonetically by [1]; the apicals are represented by such as made by contact of the tip of the tongue, as in [d, t]; the labials are represented by such as [f, p. w]; an example of velars is presented by [k]); or tone modifications, such as symptomatic signals, secondary phonemes, suprasegmentals, etc. (to signal a large variety of situational contexts). Thus it would be generally agreed, for example, that the correlation on increasing loudness of voice and rising pitch with increasing anger, threat, frustration, impatience, fear, urgency or excitement is fully iconic.4 Another interesting incident is pointed out by Wescott (1971: 423) who, quoting Ultan (1969: 42), observes that "most languages have a predominantly rising intonation pattern for questions and a predominantly falling one for statements." Wescott citing Bolinger (1957: 28) points out, moreover, that "rising intonation may be doubly iconic in view of the fact that, in many languages, questioners conjoin a raised voice with raised eyebrows." In syntactic iconicity, the order of linguistic elements parallels that in physical (i. e. nonlinguistic) experience, as reflected, for instance, in
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sequence (to signal primary or secondary importance of data in order of appearance, as in Jakobson's veni-vidi-vici, etc.). Examples are to be found in literary or narrative iconicity, irreversible binomials or polynomials, or freezes, such as in expressions like bread and butter, or life and death. As Woolley (1976: 291) has observed, it seems that here the fixed order of the conjoined elements "reflects iconically order in the universe, as perceived by the members of a culture."5 In semantic iconicity, as for instance to be found in the language of feeling, the whole linguistic apparatus collaborates to conjure up the emotive state to be imagined. These very interesting phenomena shall be dealt with in a separate paper. The above model appears to be the main ethological framework within which we perceive and signal our perception of the world around us, and our sensations and intentions within it. Interestingly, both perception and employ appear so far to be tacit and implicit. For unless this is specifically pointed out to us (i. e. made explicit), most speakers are unaware of the fact that our view of the world — and our language — are so concrete, visual and wholly localistic (i. e. spatially-oriented). Yet nolens volens the icon has us totally in its thrall! It is certainly interesting to think that we obey laws, without even being aware of their existence or content. Thus, territoriality manifested and represented by linguistic iconicity pervades our entire thinking, perception, world-view and language. From our amazingly physical, concrete and visual perception and expression of quantity (e. g. chair-chairs), quality (e. g. fat-fatter), and the distance of past as compared to present tense (e. g. missmissed), to our perception and expression of proximity and distance (e. g. here-there, this-that, near-far), or sequence (e. g. veni-vidi-vici), all we say is unequivocally translated into fixed, recurrent and predictable iconic patterns of one kind or another, falling into distinct fields. These iconic fields constitute a system, a network of variables and constants ruling our language. The sum total of these phenomena is so multifaceted, however, that ultimately only computerized work can yield a true total overview of what is going on in our language and, presumably, in our heads. At this stage of the game, I cannot deny that occasionally my expectations may have selected for me the cases that fit my theory. Problems like this, however, are a perennial concern of the philosophy of science, and theory validation is to a very great extent a matter of cumulative
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evidence. Such evidence is to be garnered from controlled experiments in current research work. We have now come to the last phase of this discussion, the place of the icon in human evolution in general, and in language evolution in specific. For just as the transition from limbic to neocortical control over our vocal signalling was one of the main stations along our onerous evolutionary road to humanity, the transition of visual to vocal iconicity implies a similar major achievement. Clearly, however, any theory of the evolution of language must also take account of (both sides of) the brain and their interactions. As Armstrong (1983) has observed, a key to organizing our thinking along such lines is provided by recent studies in the lateralization of cerebral functions. In a laudable attempt to contribute to the study of language and mind, Armstrong (1983) advocates an approach to linguistic analysis relating studies in linguistics to those in the neurology of language. This, according to Armstrong (1983), implies the "possibility of developing a comprehensive theory of the evolution of language that takes into account the range of important features of language as well as the development of its neural substrates." Armstrong (1983) judiciously observes that right hemisphere superiority for sign recognition has been revealed by recent studies (e.g. Poizner, Battison and Lane 1979, as quoted by Armstrong). He further maintains that one of the primary functions of metaphor is to " visualize" auditory language by taking advantage of these visual capabilities of the right cerebral hemisphere. Armstrong (1983) points out that this is "direct evidence for the role of the right hemisphere in visual processes underlying language use." He contends, moreover, that it is directly related to the "visualizing" processes in "connotational" and metaphoric use of spoken language. This contention can be supported by several observations concerning the use of iconic signs in visual and auditory language. "A primary problem in an auditory language," Armstrong (1983) argues, is to "render the objects of everyday life into acoustic signals, taking into account that humans, as primates, are essentially visual animals. Clearly, the problem diminishes greatly when a visual language is used, as it is much easier to produce iconic visual signs than auditory ones." Just as clearly, many of what we now consider auditory iconic signs, found their origin in visual signalling. As thought needed verbal symbols to express higher and more complex abstractions, by coordination and integration of the simpler ideas
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which could not be carried out through gestures, man has raised himself through conceptual-verbal associations above the gesture level. As observed in Armstrong and Katz (1981: 342, as quoted by Armstrong), the cognitive specialities of the two hemispheres are now well known to be differentially associated with aspects of language use, the left hemisphere being implicated in linear, referential, denotational, cognitive or analytic processing, the right hemisphere being involved in rather more visual, associative, gestalt-like (i.e. synthetic), metaphoric, connotational and iconic aspects of language use. It is obvious, therefore, that the right hemisphere, being involved in the establishment of meaning, is implicated in no less important a manner in language use. Hence, as Armstrong (1983) correctly points out, "Theories purporting to explain the evolution of brain lateralization for language must account not for language per se as lateralized to the left hemisphere, but for the lateralization of various linguistic processes to the two hemispheres separately and the joint action of the two hemispheres in the reception and production of language." Moreover, metaphor and related connotational, associational and iconic devices appear to be central to its operation, their primary function being to "visualize" auditory language by "taking advantage of the visual imaging capabilities of the right hemisphere" (Armstrong 1983). Possibly, the ancient hominid struggle for take-over between limbic and neocortical control over utterance (or between involuntary and voluntary vocal responses to stimuli), when both the necessity and the possibility arose to translate the objects and activities of everyday life into distinct acoustic signals, was ameliorated by the increasing use of meaningful visual signalling. Concomitantly, physiognomic movements, gestures and expressions may have become increasingly distinctly enphoned. The great advantage of signal languages, which is, as Armstrong (1983) has judiciously observed that "since they contain large numbers of elements which are directly iconic, natural groupings of signs which have semantic affinities may have physical similarities directly related to the nature of the semantic affinities" may well be directly reflected in the acoustic signals our auditory languages are composed of. As that may be, the birth of the linguistic icon must have been an acute, catalystic occurrence. The power of the icon as a linguistic device apparently resides in its ability to produce visual images translatable into auditory signals through the action of the whole brain.
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This remark requires some elucidation. If, as asserted above, the left hemisphere is specialized for referential, denotational, phonological and grammatical functions, and the right hemisphere is specialized for associative, connotational, morphological and semantic functions, what a theory of the evolution of language must also account for, is the three questions of when, how and why this division came about. Physical anthropologists and neurobiologists have come up with some admirably valid answers to the first two questions. With regard to the third, Armstrong (1983) has suggested that a primary problem in a developing acoustically based language would be to maintain the ability to retain visual images. He argues that this problem could be solved through the "maintenance of a linguistic link to the right hemisphere through 'connotational' processes." Hence, the conclusion is that "lateralization of aspects of spoken language to the left hemisphere results from the need to minimize competition between the two hemipsheres for use of the vocal apparatus" (Katz and Armstrong 1983). As the phenomenon known to us as linguistic iconicity thus appears best to fill the above description of indispensable link, it evidently constitutes one of nature's most necessary and sophisticated evolutionary devices, and presents therefore, to my mind, one of the most poignant and pragmatic issues in any discussion of human language origins today. Notes 1. As used in this paper, the term "semiotics" refers to the scientific analysis of signalling systems; that is, the study of signs and sign-using behavior. 2. "Iconicity" is used here roughly in the Peircian sense; more specifically, to describe linguistic elements which are in some way nonarbitrary, that is imitative of nonlinguistic reality. 3. In the case of shortness signals, the proximity may be either spatiotemporal or psychological (ultimately overlap may ensue). For instance, in truncations (cf. Landsberg, 1986c), such words as fess up (confess), member (remember), cause (because) are used to "talk in a familiar or intimate manner so as to inspire confidence — to affect a fatherly or motherly attitude in order to gain the objective—control over the other" (Roback, 1954: 276). Spatial proximity is reflected by the use of shorter words, shorter sentences, often working like a two-edged sword, so that the shorter form as it were causes the shorter distance, while the shorter distance generates the shorter form. In the pet-name or hypocoristic connotation, which can be described structurally as a shortening of the full name plus the addition of the diminutive suffix [-i] (and which is, therefore, doubly iconic), the aim is to attain or demonstrate shorter psychological distance or familiarity (e.g. Abraham-Abie, Benjamin-Bennie, Margaret-Margie, etc.). A
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shortening of the full word plus the addition of the diminutive suffix [-i] can also be found in such comfortable everyday household words as umbrella-brollie, pinafore-pinny, pyjamas-jammies, wellingtons-wellies, etc., while the formation of the diminutive by the mere addition of the suffix [-i] is encountered in many words denoting smallness, closeness, familiarity (e. g. doggie, duckey, lovey, auntie, etc.). In the case of length signals, distance or increase may be iconically represented by a graphical enlargement, as for instance in preterites (miss-missed), plurals (chair-chairs), obliques (you-your), comparatives (fat-fatter). Augmentational phenomena belong here too. As Weinreich (1968: 166) has observed, "where there is a geometric similarity between a sign vehicle and its denotata, the sign is said to be iconic. Such similarity would be exemplified by a system in which, let us say, large things are signified by long words, small things by short words, or in which plurality of denotata is signified by repetition of the sign vehicle." The principle of reduplication fits this definition particularly well, for here we find the employment of certain affixes, identical with some part of their linguistic environment, in order to express intensive action, plurality, repetition, duration, or emphasis (cf. Landsberg, 1986c). 4. The relation of sound to meaning has been extensively treated in the literature of psycholinguistics, phonetics, semantics, semiotics and stylistics, as well as anthropology. However, it has not always been made sufficiently clear, what kind of sound-meaning relationship one is dealing with. Thus we may wish to distinguish more clearly between (a) primary iconicity or onomatopoeia (cf. Lyons, 1979: 103), such as can be found, for instance, in the English word-form cuckoo, which is "iconic in the phonic, but not in the graphic, medium." As Lyons (1979: 103) has observed, a "more complex type of iconicity may hold between form and meaning, mediated by what, from a historical point of view, may be described as an extention of meaning from a basic to a transferred, or metaphorical, sense." If, for instance, there would exist in English a word resembling the cry of an owl, but meaning "wisdom," this would be a case of (b) secondary iconicity. Interestingly, as Lyons (1979: 104) observes, "Secondary iconicity has often been invoked, though not in these terms, as one of the factors operative in the origin and evolution of language." Further I should like to distinguish between (c) regular or general sound-symbolism or psychophonetics, as for instance found in poetry and literature; and (d) more specifically the sound-symbolism in words relating to spatiotemporal or psychological proximity and distance, or phonesthesia (cf. Tanz 1971). Thus, vowel modifications signalling physical or psychological a proximity-distance dichotomy, will often tend to be of the [-i-]/ [-a-] (or generally high/low, light/dark) variation, as in English this-that, herethere, near-far, drink-drank, etc. (cf. Landsberg 1980 c). Smallness and bigness (e.g. little-large) may be thus signalled. For the proximity-i in expressions of connexion or belonging, possessives, tribal names or languages, see Landsberg 1986c. Consonant modifications are exemplified by such sets as big-small, which appear to be countericonic vocally, but where it is the consonants which carry the iconic message: labials and velars connoting bigness and laterals and apicals connoting smallness (cf. Wescott 1971: 421). For some interesting work on consonant symbolism see further Ellenbogen (1972), Foster (1982), Jacobowitz (1968), Landsberg (1982c), Nichols (1971), Pesot (1982).
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5. Sequence is one of the most conspicuous phenomena representing syntactic iconicity (cf. Landsberg 1980c: 94). Lyons (1979: 511) has observed that to the extent that "the order of elements in language parallels that in physical experience or the order of knowledge" (Greenberg 1963: 103, 1966; cf. Friedrich 1975), a language is iconic rather than arbitrary. Furthermore, Lyons (1979: 511) points out that "in so far as transitivity and causativity are associated with motion from a source to a goal, there may well be grounds for believing, as many scholars have done, that in referring first to the agent one is adopting as the communicative point of departure what is also the more natural cognitive point of departure." As Lyons (1979: 511) observes, "Many nineteenth-century linguists took this view (cf. Sandmann 1954); and it would seem to have at least some foundation in the facts." Lyons (1979: 511) further points out that Gruber (1967, 1975) has argued that "subject-predicative constructions develop, ontogenetically (and in some, but not all, languages), out of topic-comment constructions; and he has linked this with the development of constative out of prior performative constructions." As Lyons (1979: 511) observes, "much the same view is taken by Bates (1976); and it is relatable to earlier speculations about the origins of grammar." However, Lyons (1979: 511) finds it " arguable that grammar, and more especially syntax, develops by virtue of the 'freezing' of what was originally iconic into what is subsequently an arbitrary 'formal requirement' and the progressive decontextualization of utterances." (See also Wescott 1971: 424-5). When discussing word-order we may wish to mention literary or narrative phenomena as mentioned by Bal (1977, 1978a, b), and further such as discussed in Cooper and Ross (1975), Landsberg (1982b: 365), Malkiel (1968), Moeser (1975), Mohan (1974), Richards (1974), Traugott (1973, 1975, 1978), Waugh (1976), Jakobson (1970) and Woolley (1976) were mentioned above. Jakobson's (1970: 27) example of the chain of the verbs — veni, vidi, vici—as he observes, "informs us about the order of Caesar's deeds first and foremost because the sequence of co-ordinate preterits is used to reproduce the succession of reported occurrences." Moreover, as Jakobson (1970: 27) judiciously observes, "the temporal order of speech events tends to mirror the order of narrated events in time or in rank. Such a sequence as 'the President and the Secretary of State attended the meeting' is far more usual than the reverse, because the initial position in the clause reflects the priority in official standing." Jakobson (1970: 28) quotes Peirce as having "vividly conceived that 'the arrangement of the words in the sentence, ..., must serve as icons, in order that the sentence may be understood.'" Finally, some important recent studies focusing on syntactic iconicity deserve mention here: Cooper and Ross (1975), Haiman (1980, 1985), Justice (1980), Posner (1980), and Ross (1982).
References Armstrong, David F. 1983 Whorf, Stevens and the evolution of language. (Manuscript). Armstrong, D. F. and S. H. Katz 1981 Brain laterality in signed and spoken language: A synthetic theory of language use. Sign Language Studies 33. 319-350.
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Bai, Mieke 1977 1978a 1978 b Bates, Ε. 1976
Narratologie: Les Instances du Recit. Paris: Klincksieck. L'iconicite narrative. Zagadnienia Rodzajow Literackich 23(1). 11-18. Mise en abyme et iconicite. Litterature 29.
Language and Context: The Acquisition of Pragmatics. New York: Academic Press. Bolinger, Dwight 1957 Interrogative Structures of American English. (American Dialect Society Publication 28). Alabama: University of Alabama Press. Cooper, William E. and John R. Ross 1975 World order. In Robin E. Grossman (et al.) (eds.), Papers from the Parasession on Functionalism. 63-111. Chicago: Chicago Linguistic Society. Ellenbogen, Maximilian 1972 The Loom of Mind. (Manuscript). Foster, Mary LeCron 1982 Meaning as metaphor, II. Quaderni di Semantica 3(2). 313-321. Friedrich, P. 1975 Proto-Indo-European Syntax. (Journal of Indo-European Studies, Monograph I). Batte: Montana. Greenberg, Joseph H. (ed.) 1963 Universals of Language. Cambridge, MA: M.I.T. Press. Greenberg, Joseph H. 1966 Some universals of language with special reference to the order of meaningful constituents. In Joseph H. Greenberg (ed.), Universals of Language. 2nd ed., 73-113. Cambridge, MA: M . I . T Press. Gruber, Jeffrey S. 1967 Topicalization in child language. Foundations of Language 3. 37-65. 1975 "Topicalization" revisited. Foundations of Language 13. 57-72. Haiman, John 1980 The iconicity of grammar: Isomorphism and motivation. Language 56(3). 515-540. Haiman, John (ed.) 1985 Iconicity in Syntax. Proceedings of a Symposium on Iconicity in Syntax, Stanford, June 24-26, 1983. Typological Studies in Language Series, Vol. 6. Amsterdam, etc.: Benjamins. Jacobowitz, Jacob 1968 Monogenesis of Language. Jerusalem, Mass. Jakobson, Roman 1970 Quest for the essence of language. Diogenes 51. 21-37. Justice, David B. 1980 Iconicity and association in phonology, morphology, and syntax. Romance Philology 33(4). 480-489. Katz, Solomon H. and David F. Armstrong 1983 Neural correlates of right-left dual classification systems: A reanalysis of Hertz's La Preeminence de la Main Droite. Paper presented at the International Transdisciplinary Symposium on Glossogenetics, 1981.
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Landenberger, Donald E. 1973 Territory. In Encyclopedia Americana 26. 522-523. New York: Americana Corporation. Landsberg, Marge E. 1980 c The icon in semiotic theory. Current Anthropology 21(1). 93-95. 1981 b On iconicity and semiotics: Reply to Feldman. Current Anthropology 22(3). 302-305. 1982 b The formal structure of sense: A systemic analysis. Quaderni di Semantica 3(2). 293-301. 1982 c On the origin of meaning. Quaderni di Semantica 3(2). 257-269. 1984 ). In a study which I conducted shortly before our Paris conference, and which I presented at the 1981 Annual Meeting of the Semiotic Society of America in the fall following our conference, I examined whether and, if so, how gestures are translated (von Raffler-Engel 1986). This study analyzed the translation behavior of laymen. For the purposes of a cultural comparison, the behavior of laymen seemed preferable to that of professional interpreters. Because of my easy access to them, both the models and the interpreters were university students. This made certain that they were close in age and fairly close in socio-economic status (SES). Subjects were matched for sex. A videotape was prepared depicting a short dialog between two white native speakers of American English, one male and one female, supposed to be siblings. The instrument was shown to eight male and female pairs of foreign students at the same university. These subjects were asked to translate into their own language what they had just heard, and they were, at their turn, videotaped while so doing. The English language videotape was shown to one pair of subjects at a time, stopping the machine whenever one of the participants in the dialog had completed an utterance, simulating a fairly normal session of consecutive interpreting. No mention of kinesics was made to the subjects. The videotape of the corresponding translation was shown to a panel of two judges who were native speakers of that particular language, one male and one female, for each group concerned. The judges were requested to comment on what they saw, and the original English version was never mentioned to the judges. None of the judges made any remarks about the behavior of their compatriots on the screen. It can thus be safely assumed that their gestural behavior appropriately matched both the language they spoke and what they said. For the analysis, each set of performances (the original plus the translation) was viewed on two monitors at the same time, so
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that the gestural behavior accompanying the corresponding verbal utterances could be clearly established in a parallel fashion. Given the constraints in time and manpower for this pilot study, only the first sentence was selected for the comparison. A professional designer then copied the body motions from the monitors. The actual speaker was drawn in full lines while the listener was drawn in dotted lines (see illustrations in appendix). Illustrators were selected from the gestural repertoire, because illustrators are most closely connected with the referential part of the conversational interaction. Their transfer is safer to study than that of regulatory or affective gestures, because their meaning is readily evident from the verbal component of the dialog. The parallelism of referential gestures in different languages is easier to control for extraneous variables than that of other types of gestures, which are less apparently related to easily quantifiable parts of the verbalization. The technique for measurement of body motions followed Wallblott (1980). The basic theme of the conversation was money. During the first sentence ("Well, it was your idea in the first place"), the female model arrives, hands hanging down along her sides, steps slightly forward, then stretches out her right hand with pointing finger. She then turns her entire body to the right side. While the general postural motions are strikingly similar in all interpreters, only the Brazilian-Portuguese, French, German, Korean, and Philippino-Tagalog speakers use a pointing gesture with arm stretched out, in a manner virtually identical to the American model. The Icelandic, Japanese, and Pakistani-Urdu speakers have no such arm movement. The Icelandic woman is the only one of these three who manifests hand movement at this point. When she arrives, her hands are closed in a loose fist. She then opens both hands to an extended palm, and then closes them again, eventually positioning both hands in front of her lower waist. Icelanders are very traditionalistic but also very low kinesic people. For the Japanese and for the Urdu speakers, the reason for their kinesic quiet most probably lies in the traditional malefemale relationship, which is very strong in their countries. Interestingly, when asked to translate the videotaped brother-sister discussion about money, the Japanese man said to my student, Eric Unger, who was running the experiment, that he was willing to translate for us, but that in Japan such a discussion was unthinkable. A sister does not accuse her brother.
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The status of women in Japan and in Moslem countries determines that strong accusatory gesticulation towards men is not admissible on the part of the former. The close similarity between the postural behavior of the model and the interpreters in all instances, including the latter, shows that translating automatically implies the transfer of the verbal and the nonverbal component of what has to be translated. Cultural constraints influence both. What universally underlies the process of communication among humans, and consequently of translating from one language into another, is the interdependence of kinesics and verbalization. The two components are present, even when people are alone and, theoretically, the gesticulation serves the encoder function only (Cohen 1980). Noises in the environment exert only a minimal impact on amount of gesticulation (Buckner 1980). In psychoanalysis, performance of the related body movement facilitates the recall of an event in verbal terms (Mahl 1979). In thinking and in communicating, the verbal and the nonverbal component are present across all cultures and are observable in ontogeny (von Raffler-Engel 1980). Their cooccurrence is therefore inherent in language qua language and, consequently, most likely to have been part of language from its origin. Cross-cultural universality coupled with ontogeny points to phylogeny. If there is a 'bioprogram' for language, jointly with language there must have been a bioprogram for kinesics. When I mention the language bioprogram, it is obvious that I refer to Bickerton's (1981) book. Of all the publications that have appeared or, rather, that I have happened to read since our Paris meeting, Bickerton (1981) is the one that has most strongly reinforced my conviction that the theory of glossogenetics which I proposed in Paris is basically correct. This, in spite of the fact that, except for criticizing the theory of gestural origin, Bickerton does not deal with gesticulation in his book. What made this book so appealing to me in the first place is that the autor rejects the mind-body dichotomy and does not adopt the structuralist position. He also does not take the easy route of constructing sequences of psychological development to suit an a priori hypothesis. He did not simply proceed to rationalize a series of axiomatic assumptions of his own making, as did Chomsky and his followers and epigones of various generative schools. Instead, Bickerton induced his hypothesis and tested it against the physical reality of the data he collected during his long years as a Creolist.
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It is on this empirical evidence that he built his theory concluding "that there is an innate bioprogram that determines the form of human language" (Bickerton, 1981: 134) on the analogy of the bioprograms for physical and cognitive development. Bickerton's bioprogram consists of a language-specific set of rules that are genetically transmitted and released in developmental order. Contrary to the strategy-forming as well as the hypothesis-testing schools of language acquisition theories, "the bioprogram is not present at birth but unfolds progressively during the first four years or so of life" (Bickerton, 1981: 199). Language acquisition takes considerably longer and is completed only at about ten years of age. However, this error is not vital in refuting the theory. It is simply an overflow of the many misconceptions about child language that became popular during the sixties in the United States. The obvious differences in the world's languages are not rationalized away by ingenious universal schemes, but openly admitted and explained within generally accepted terms of genetics. "Cultural evolution works faster than biological evolution, and since it operates on a far more abstract level, the effects of cultural evolution of language could not be transferred to the gene pool" (Bickerton, 1981: 296). In the glossogenetic theory which I proposed in Paris, a distinction was drawn between genetic inheritance and two learning periods, pre-natal and post-natal. Bickerton's conclusion that some language constructs are easier for the child to acquire than others is supported by observations in the same sense that I made on bilingual children some fifteen years ago, when such statements were wholly ignored, as they did not fit the trends of the time. I have also been puzzled in the past how in certain words secondary onomatopoeia can have been discontinued through historical change. However, the evidence for sound symbolism is so clear that I did not feel that the idea could be discounted. Bickerton's theory finally provides the answer to this apparent paradox. "The biological language self-destructed. It had made possible the construction of cognitive maps... which enabled their users to enter... a domain in which events could be predicted and forestalled and even altered" (Bickerton, 1981: 290). This is why our cultural differences are greater than our physical differences. As I said in Paris, according to my theory, language as we speak it now, is not inherited by genes. From the start, I objected to the idea that all possible grammars are programmed into some sort of
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Language Acquisition Device (LAD), making of language acquisition a process of forgetting through an algorithmic searching device. Such an organization goes counter to the principle of economy which pervades natural development, and would make mental development too different from physical development to be plausible without resorting to the old mind-body dichotomy. The maturational curve for communicative ability leading to the complexities of adult language begins at conception, like all other aspects of life. Following my theory, it is therefore possible that some features of language are acquired before birth, while others are acquired only after the child is born. I use "features of language" in a broad sense. Linguists would probably prefer that I speak of prelinguistic features, while psychologists might term them cognitive features which are prerequisite to the capability of acquiring language. I fully maintain my original approach to first language acquisition. However, I will admit that it has been greatly clarified by Bickerton's ideas: I can now see more trenchantly the relation that obtains between features of language and features of cognition, and would no longer leave language features highly unspecified. The way grammar organizes the treatment of the distinction between topic and comment in the various languages of the world is of strictly linguistic concern. However, the psychological prerequisite that allows man to distinguish between topic and comment and express that relationship in overt fashion is a necessary feature of language. All that ist characteristic of language qua language is part of language in the broad sense of the term. In my Paris paper I listed the language features for which the child is programmed during his uterine stage and immediately following birth. For clarity's sake I will repeat them here: Uterine Stage I. Awareness of self as distinct from the environment. This is a prerequisite for communicative interaction. It is also a prerequisite for the cognitive mapping of the world. Bickerton strongly opposes the origin of language from a prior communicative system, and sees no continuity between hominid calls and verbal language. For him, "Language grew out of the cognitive system used for individual orientation, prediction, etc." (Bickerton, 1981: 267). I see no contradiction in what I suggested and what Bickerton has proposed. True, shrieks and laughter do not overlap with language, but neither are they primarily communicative in intent. To
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my mind, it is very important that we should never forget that man is a social animal (von Raffler-Engel 1964: 99) and, therefore, cognition and communication are closely linked for survival. Autistic children are not normal, whatever their intelligence quotient in absolute terms. The deaf who, from birth, communicate in sign language with their parents, are able to learn oral language even past the optimal age for language acquisition. Deaf children who did not have this natural advantage right after birth, have greater difficulties even when they are forced into oralism at a very early age and systematically prevented from expressing themselves gesturally. Once they missed out on neonatal and infant communication, their power to learn language is impaired. Uterine Stage II. Awareness of differences in the environment. Crucial is the awareness that a fundamental difference obtains between inanimate objects and animate ones. The ability to distinguish between objects, such as light and noise, is not the same as the ability to understand that objects are radically different from living beings. Objects are passively perceived while living beings will interact. Under living beings, at this time, I count only humans. I have not observed whether there is any interaction between an unborn child and a cat curling up in the mother's lap. To my knowledge, no research is available on the subject. The unborn's first significant other is his mother, who interacts with him vocally and tactically. Bickerton's (1981: XIII) assertion that the bioprogram for language "can function even in the absence of adequate input" helps to explain how it is that many children are able to master adult language even when their mothers did not want them and eventually gave them up for adoption, or even unsuccessfully tried to abort them. When the child receives no affective interaction as an infant, he will not develop normal language, and passive exposure to radio or television is not enough. A modicum of interactional communication is necessary. Exposure to spoken language alone is not sufficient to develop communication skills. Neonatal Stage I. Differentiation between the regulatory and the referential category. The child's needs are differentiated. He will engage in reciprocal gaze with his mother to satisfy his emotional needs. He will cry and kick to demand food. Neonatal Stage II. Differentiation between significant others. Mother is no longer his sole communicative correspondent and, con-
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sequently, variation in strategic behavior is needed to reach one and the same goal. I have stressed the communicative factor throughout. On the surface, this is in total contradiction to Bickerton (1981: 220), who vigorously opposes the "communciative hang-up." For him, "The distinctiviness of human language is not what it shares with call systems ... but in how it differs from call systems ... Language communicates concepts, call systems communicate stimuli" (Bickerton, 1981: 220). When one looks carefully at the data presented by Bickerton, paradoxically, one finds that they really do not support an anti-communicationalist position. When a one-year-old says "apple," does he express a concept when he simply points to the fruit, and a stimulus when he wants to have it? "Apple" is a precept and "fruit" is a concept. Does this mean that when a child calls all edibles "apple", "apple" is a concept which eventually becomes a precept when the child can say "pear"? In the child's mind, apples and balls may belong to one concept and pears and cookies form another. This should not constitute a problem for Bickerton (1981: 234) for whom the truly human nature of language consists in our ability to name progressively more abstract phenomena, culminating in such comprehensive abstracts as are flora and fauna. What I fail to understand is why a stimulus cannot evolve into a concept. Feral children do not speak, but children of pidgin-speaking parents create Creoles. Would this not point to communication as a necessary condition for the activation of Bickerton's language bioprogram? In the book it is not mentioned whether an only child interacting exclusively with his parents would create a Creole, or whether creolization happens only among siblings and peers. The relationship between thinking and language is an age-old problem and I certainly have no solution to offer. I have some doubts that "Possession of an elaborated world-view must precede, not follow, communication on even the lowest of lingiustic levels" (Bickerton, 1981: 235). I see no reason why the desire to communicate cannot be viewed as the basis for the beginning of language. I almost believe that without the desire to communicate we would not need the elaborate grammar that characterizes human language. Do pidgin speakers think in their native language or in an ad hoc private Creole? The fact is that pidgins creolize when the desire for communication becomes more varied, with greater need for specialization and
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displacement in the language. It is true that animals have rudimentary forms of communication, but never advance to languagelike systems. It is therefore man's intellectual power that must be responsible for language. On this I agree with Bickerton (1981); however, the quantum leap to the human system which can be used for cultural transmission is not exclusively intellectual, not to mention the fact that the isolation of intellect is an artifact of philosophy. I am not prepared to venture an even semi-educated guess about when the language bioprogram reached its crucial stage. However, I would not exclude communication factors as the prime movers. The traditional socio-anthropological theories of language origin do not negate the possiblity of a bioprogram. Communication is closely tied to affect. Neurology teaches us that nature is parsimonious in organizing principles and rich in adaptations. Consequently, "In phylogeny, the same mechanism is used over and over again to meet new and different adaptive needs" (Kinsbourne 1981: 56). According to Bickerton (1981: 242), due to the greater neural strength of the oldest inheritance, the most primordial distinction should be the first lexicalized. In child language, indeed, the first lexical expression refers to food or its provider. Before the infant masters adult-like language, his earliest vocal expression also refers to these. The baby's cry manifests his need. Hearing infants of deaf parents will eventually cease crying and use other means for communicating. They will develop sign systems not because they are not born with a language bioprogram, but because vocal language is not useful to them. I do not know whether this signing develops along the same semantic lines as the bioprogram, but this is entirely plausible. There is no conflict between the presence of a language bioprogram and my suggestion at the Paris meeting that affect is the root of language development. Certainly, sapientization implied "filling the gap between talking only about observables in the external world and communicating the contents of one's mind" (Bickerton 1981: 276). Is not a spoiled baby's insistent crying so that he be picked up an expression of what he has in mind? Pouting to show displeasure is more than a stimulus. That I personally do not find it at all easy to mark the boundaries between stimuli, precepts, and concepts, is beside the point. What is important is that "To be able to tell realis from irrealis is a crucial part of being fully human" (Bickerton 1981: 285). When the baby expresses a need, he probably has indeed some
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memory of his previous satisfaction, and he is cognizant of the present lack of it. Bickerton may not be happy with my conclusions, but I must admit that most of his baselines have reinforced my belief in affect as the prime factor in language development. Previous to the realis-irrealis distinction Bickerton (1981: 286) posits the awareness distinction. The latter is already acquired in utero when the fetus can sense single events against his customary steady state. Without this awareness there could not be any distinction of irrealis. The grammatical sequence of beginning Creoles recapitulates the ontogeny of perception and of communicative interaction. The case for phylogeny is therefore fairly strong. Maybe we have found the much needed "biological reality" championed by Bickerton (1981: 294). Animals also have a memory (they dream), and an awareness of irrealis distinctions. How come they did not develop language? It is impossible to give a scientific answer to this question. Incidentally, I have far less faith in chimps than does Bickerton. To answer that humans have a language bioprogram and animals do not, is evading the fundamental question. I frankly admit that I will avoid this question, and all I have tried to do is delineate a sequence of biologically plausible behaviors that may have led to language as we know it today. Earlier in this paper I insisted on the unity of mind and body. I would like now to emphasize the unity of the activities that go on inside the mind. Luckily, in this belief too, I am no longer as lonely as I was years ago. Recognition of the artificiality of separating intellect and emotion is finally dawning also on the academic establishment. I am quoting from an official publication of the Social Science Research Council of the United States of America: "More recently, the committee has turned its attention to affect and emotional development. Much of this attention has emerged from studies of cognition: ways in which cognition and affect necessarily interact. This research indicates that cognition and affect may be far less independent systems than some theories propose or some scholars espouse" (Sherrod 1983: 13). The books of Herzka (1979) and Izard (1982) richly illustrate the high degree of expressivity of baby faces. Given the identifiability of several types of emotions in the facial expression of the newborn and, most importantly, given that such expressions can be elicited as responses to smiles and vocalizations by other human beings, I feel at ease in reiterating the suggestion made in my Paris paper that affective communication was present already in the fetal stage.
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My theory is in fundamental disagreement with some current authors for whom "One of the least understood aspects of emotion is their evolution from physically nonverbal expression into emotional experiences that possess complex verbal and cognitive components" (Sherrod 1983:11). The baby's cry is vocal and, most significantly, at a very early stage there already appears verbal communication by means of a set of "emotive vowels" (von Raffler-Engel 1964: 99 — 102). Verbalization in a rudimentary linguistic form constituted of a single vowel is the obvious precursor of complex verbal language. When emotion is purposely communicated it does involve cognition. As I see it, cognition is present at birth and before. In ontogeny, there is no sudden leap either in cognition or in verbal language. Both are developed from simpler forms, exactly like locomotion and other types of physical behavior. As I see it, the preparation for language begins in the womb. It is also during this early period of life that cerebral dominance is established (Kinsbourne 1976). Of course, we cannot say for sure that ontogeny recapitulates phylogeny. However, combined with Bickerton's (1981) findings from the process of creolization and the evidence of the synchronization of verbal and nonverbal behavior throughout man's life span, that is as much as we have to go by. In summary, evidence in support of my theory comes from: 1) Ontogeny (based on my theory of language acquisition, in von Raffler-Engel 1964); with special attention to the prenatal stage. 2) Language as structured and used today (based on my ongoing research in nonverbal communication, 1970—1986); with special attention to interactional behavior. 3) Creolization (as exposed by Bickerton 1981). The theory that I proposed during our previous meeting may have had many flaws, and I am sure that I will detect many more myself as I go deeper into the study of glossogenetics. It has, nevertheless, the advantage that it does not fly in the face of all available evidence, as do the catastrophe theory and the gestural theory. I would like to conclude my paper with the beginning statement of Givon's (1979: 272) chapter on phylogeny supporting "the legitimacy of viewing human language as the latest link in a long, gradual development of communicative systems via many intermediate stages in hominid evolution." In my view, the vocal and the kinetic systems were coordinated from their inception.
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Appendix
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References Bickerton, Derek 1981 Roots of Language. Ann Arbor, MI, Karoma. Bonavoglia, A. 1983 Mourning the stillborn. Psychology Today 17(7). 74. Buckner, J. 1980 Seen but not heard. In W. von Raffler-Engel (ed.), Aspects of Nonverbal Communication. 275 — 280. Lisse, Holland: Swets and Zeitlinger. Cohen, A. A. 1980 The use of hand illustrators in direction-giving situations. In W. von Raffler-Engel (ed.), Aspects of Nonverbal Communication. 265—274. Lisse, Holland: Swets and Zeitlinger. French, R and M. Dorfman 1981 Foreword. In B. L. Hoffer and R. N. St. Clair (eds.), Developmental Kinesics: The Emerging Paradigm. IX —XIII. Baltimore, MD: University Park Press. Givon, Talmy 1979 Language and phylogeny; the SOV mystery and the evolution of discourse. In (Author) On Understanding Grammar. 271—309. New York: Academic Press. Herzka, H. S. 1979 Gesicht und Sprache des Säuglings. Basel, Switzerland: Schwabe & Co.
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Izard, C. 1982 Measuring Emotions. New York: Cambridge University Press. Kinsbourne, Marcel 1976 The ontogeny of cerebral dominance. In Robert W. Reiber (ed.), The Neuropsychology of Language. 181 — 191. New York: Plenum. Kinsbourne, Marcel 1981 Neuropsychological aspects of bilingualism. In Harris Winitz (ed.), Native and Foreign Language Acquisition. 50 — 58. New York: The New York Academy of Sciences. Levelt, W. J. M., G. Richardson and W. Lahey 1983 Study of the temporal relations holding between deictic gestures and speech. 21—22 Annual Report Nr. 3, 1982. Nijmegen, Holland: MaxPlanck-Institut für Psycholinguistik. Levy, Elena 1982 Towards an objective definition of 'discourse topic.' In Kevin Tuire, Robertson Schneider and Robert Chametzky (eds.), Papers from the eighteenth regional meeting of the Chicago Linguistic Society. 295 — 304. Chicago, IL, University of Chicago, Linguistics Department. Lorenz, Κ. 1979 Das Jahr der Graugans. München & Zürich: Piper. Mahl, G. F. 1979 Body movement, ideation, and verbalization during psychoanalysis. In Ν. Freedman and S. Grand (eds.), Communication Structure and Psychic Structure. New York, Plenum. (Reprinted in S. Weitz (ed.), Nonverbal Communication: Readings with Commentary. 168 — 181. New York: Oxford University Press. Powledge, Τ. M. 1983 Windows on the womb. Psychology Today, 17(5). 3 6 - 4 2 . Raffler-Engel, Walburga von 1964 II prelinguaggio infantile. In Studi Grammaticali e Linguistici. P. 64 ff. Brescia, Italy: Paideia. 1975 The correlation of gestures and verbalization in first language acquisition. In A. Kendon et al. (eds.), Organization of Behavior in Face-toFace Interaction. 241—250. The Hague: Mouton (World Anthropology). 1980 Developmental kinesics: The acquisition of conversational nonverbal behavior. In (Author) (ed.), Aspects of Nonverbal Communication. 133 — 160. Lisse, Holland: Swets and Zeitlinger. 1983a On the synchronous development of gesticulation and vocalization in man's early communicative behavior. In Erich de Grolier (ed.), Glossogenetics: The Origin and Evolution of Language. Proceedings of the International Transdisciplinary Symposium on Glossogenetics. 295 — 311. Chur, Switzerland: Harwood Academic Publishers. 1985 Unconscious elements in cross-cultural communication. In Richard J. Brunt, and Werner Enninger (eds.), Interdisciplinary Perspectives at Cross-Cultural Communication. 65 — 78. Aachen: Rader (Aachener Studien zur Semiotik und Kommunikationsforschung, Band 2).
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1986 The transfer of gestures. Semiotica 62-1/2, 129-145. Raffler-Engel, Walburga von, K. Newman, R. Foster and F. Gantz 1980 The relationship of nonverbal behavior and verbal behavior in the evaluation of job applicants. In Walburga von Raffler-Engel (ed.), Aspects on Nonverbal Communication. 357—374. Lisse, Holland: Swets and Zeitlinger. Riseborough, M. G. 1982 Meaning in movement: An investigation into the relationship of physiographic gestures and speech in seven year olds. British Journal of Psychology 73. 497-503. Sherrod, L. R. 1983 The Council's role in research on child development. Social Science Research Council Items 37(1). 8 - 1 7 . Wallblott, H. G. 1980 The measurement of human expression. In Walburga von RafflerEngel (ed.), Aspects of Nonverbal Communication. 203—228. Lisse, Holland: Swets and Zeitlinger.
Behavioral flexibility and the evolution of language Willem de Winter
Abstract In this paper the relationship between behavioral flexibility and human language is investigated, and its consequences for the study of the evolutionary development of language capacity are discussed. It is observed that behavioral flexibility and human language show remarkable similarities in formal organization, and that the emergence of either capacity in both phylogeny and ontogeny appears to coincide with a shift in control from limbic to neocortical regions. It is argued, therefore, that human language is the consequence of an application of the more general organizational principles of behavioral flexibility, both formal and neurological, to the specific behavioral faculty of communication.
1. Introduction The capacity to communicate in a natural, human language is traditionally seen as the major qualitative difference between man and animal. This position has, however, become a subject of severe attack on the basis of results attained from recent experiments in teaching artifical languages to chimpanzees (e.g. Gardner and Gardner 1980; Rumbaugh 1980). To be sure, these experiments have shown that chimpanzees and gorillas can be trained to engage in an extensive amount of symbolic communication. It remains, however, a matter of debate whether this potential reflects, even in a rudimentary form, the same capacity that allows humans to communicate in a natural language (e.g. Chomsky 1980; Fouts 1976; Malmi 1980). The origin of this controversy can often be retraced to different concepts of language; indeed, an uncontested,
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comprehensive definition is still lacking. 'Human language' stands for the specific human capacity. A wealth of evidence indicates that human language is a genetically based, species-specific adaption and, therefore, must be a product of biological evolution (e. g. Lenneberg 1967). This observation is often used to support the traditional language dichotomy. It should be realized, however, that the direction of a novel evolutionary development depends chiefly upon preexisting capacities already present in the gene pool (Dobzhansky et al. 1977). Thus, "a novel biological system can arise by evolution only if the genetic raw materials for its construction are available for natural selection. At least some of the genetic building blocks from which the new system is to be made must be older than the system itself' (Dobzhansky et al. 1977: 451). This axiom is crucial if one is to reconstruct the evolutionary developments that have led to the emergence of human language. The apparent cognitive and communicative capacities of the great apes should also be considered in this light.
2. Animal Communication Communication in most animal species is a form of social behavior which is characterized by the production of relatively stereotyped actions, that represent unequivocal messages about the state of the 'sender,' and to which the 'receiver' responds in relatively stereotyped ways (Jerison 1983). From several studies it appears that nonhuman primate communication is characteristically mammalian, rather than a novel development (Moynihan 1970; Myers 1976); "so that the ape, like the monkey, expresses itself in ways that have more in common with a dog or a cat than a human language user" (Malmi 1980: 193). Of course I am referring in this section to natural communication systems. 2.1 Vocal communication in nonhuman primates All data suggest that nonhuman primate vocalization consists of a species-specific, limited set of relatively fixed expressions, which elicit relatively fixed responses. Accordingly, there is no evidence that these animals have the ability to recombine qualitatively dif-
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ferent vocal units, separately meaningful, into new messages with new meanings. In other words, their communication systems have no syntactical openness (Marler 1975). Comparative studies of nonhuman primate communication systems reveal that these systems have a fundamendally emotive or affective nature. Messages in these systems only rarely convey information about the physical environment. An exception to this rule is found in rhesus monkeys, which seem to possess predatorspecific alarm calls (Marler 1980). But even in those few cases in which such nonaffective information does seem to be transmitted, nonhuman primates show no ability to separate the informational components from the emotional or affective charge (Limber 1980). These observations are confirmed by recent neurological studies, which suggest that animal communication and vocalization are mediated by the 'primitive' limbic structure of the brain (e. g. Myers 1976; Robinson 1976), which are generally considered as the motivational centers of the mammalian brain (Ganong, 1979; Robinson 1976). It is likely that this coupling of communication and emotion is a crucial factor for the effectiveness of alarmcalls in dangerous situations (Marler 1980).
3. Human language In contrast to animal communication, human language is largely governed by neocortical tissue (e. g. Geschwind 1970; Maruszewski 1975), which is reflected in the fact that in human language, information exchange can take place independently of affect (Limber 1980; Robinson 1976). It has been suggested that human language depends on two systems rather than one (Robinson 1976). The first and phylogenetically older system, then, which is supposed to be located in the limbic system, is closely related to emotional, motivational and autonomic factors, and is capable of transmitting only signals of low informational content. The second, supplementary system, species-specific to man, has arisen from newly developed neocortical tissue. It is usually lateralized in the left hemisphere, and allows for a greater independence from emotional factors. It is supposed that "this new system rose in parallel with the old, surpassed it, and relegated the old system to a subordinate role" (Robinson 1976: 765).
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3.1 The grammatical organization of human language The most fundamental distinction between human language and animal communication is that language is an 'open' form of communication: a virtually unlimited number of functionally distinct expressions can be formed. In modern linguistics (e. g. Chomsky 1980), it is supposed that such a communication system is based on a finite system of rules that specify the properties of this infinity of expression, i. e. a grammar. The following passage gives a clear exposition of this theory: "In the case of human language these (grammatical) principles crucially involve a hierarchy of phrases, abstractly represented, and structure-dependent rules operating on these phrases. Recursive embedding is the basic device for constructing new phrases." (i. e. one phrase can be embedded in another phrase, resulting in a new phrase, which in turn can be embedded in still another phrase, etc.). "The structures formed by various processes of recursive embedding are assigned phonetic and semantic representation by further rules. These devices provide for the range of expressions characteristic for all human languages, allowing us to denote previously unexamined or newly-imagined objects, actions, properties, events, etc., and to form propositions of various sorts. These are the most basic and elementary properties of human language; they account for the traditional observation that human language is a system for the infinite use of finite means" (Chomsky 1980: 431). Interestingly, Chomsky underwrites the proposition that the capacity to symbolize, specifically the capacity to attach 'meaning' to abstract labels such as words, concerns cognitive systems that are connected only in part to the capacities that are basic to human language. In other words, symbolization is thought to be a more universal capacity, that is not restricted to communication. So the grammar of a particular language refers to the system of rules and principles that specifies the properties of its expressions. The term "universal grammar" is used to refer to the system of principles to which any grammar must conform as a matter of biological necessity, i. e. as a consequence of certain organizational characteristics of the human brain. Accordingly, universal grammar has a genetic basis, and determines the essential nature of human language, whereas each grammar specifies a particular instance. In other words, the term universal grammar refers to the genetically
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coded organizational constraints of the system called 'human language;' each particular grammar is a structural representation of these constraints (de Winter 1984).
3.1.1 Duality of patterning In addition to phrase-structure, Hockett stresses the importance of the phonetic structure of human language to account for its openness (e. g. Hockett and Altmann 1969). His fundamental principle in this respect is "duality of patterning," i. e. the fact that language shows patterning in terms of arbitrary but stable meaningless signalelements, and also patterning in terms of minimum meaningful arrangements of these elements. In other words, Hockett would call 'language' only those communication systems that use a compositional code in which the elementary meaningful units (morphemes) are assembled out of smaller recurrent meaningless units (phonemes), i. e. patterning on the first level. In addition, the system must provide for second order patterning by which these elementary meaningful units can be combined into larger sequences (i. e. Chomskyan phrase-structure), and conventions governing what sort of meanings emerge from the arrangements. With this description of the syntactical structure of language, Hockett stresses the fact that, to account for the openness of language, it is not sufficient just to allow for the syntactical combinability of words or signals. It is essential that this capacity to generate new combinations is coupled to the capacity to attach different meanings to different combinations. Thus, in addition to the conventions that establish and fix the meaning of individual signs (lexical semantics or symbolization), the capacity must exist to handle a second set of conventions that establishes and fixes the semantic or symbolic function of sign combinations (syntactical semantics) (von Glasersfeld 1976). In summary, the structural characteristics of human language that distinguish it fundamentally from all animal communication, and account for its openness, "include the isolation from the stream of speech of discrete component units (phonemes, morphemes) which can be combined into a seemingly infinite variety of new wholes; the organization of units on at least two distinguishable hierarchical levels simultaneously (duality of patterning), vastly increasing the possible number of new combinations; and the exist-
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ence of rules for combination (syntax, grammar) which group component units into categories and channel (limit) innovative combinations" (Peters 1981: 683).
4. Behavioral Flexibility Human speech is based on the temporal patterning of acoustic units. Each pattern is related to a particular sequence of neuromuscular events (Lenneberg 1967; Steklis and Harnad 1976). A monkeycall, however, is also based on a particular neuromuscular sequence. What accounts for the difference between human speech and animal vocal communication, is the fact that the organization of the human brain allows for the virtually unlimited rearrangement of speechcorrelated neuromuscular sequences, whereas in animals these sequences are genetically preprogrammed with relatively little modifiability. In other words, they have no volitional control over their vocal apparatus (Myers 1976). Differences in the anatomy of the vocal tract cannot account for the fundamental differences between nonhuman primate vocal communication and human speech (Wind 1976). Sequencing, in fact, is a basic feature of the Central Nervous System (C.N.S.) in all vertebrates. This becomes obvious if one realizes that every behavioral action involves movement. It is movement which is organized, and goal-directed, and which creates an action system (Locke 1978). Movement is the result of muscle contractions, and it is the sequence of muscle contractions which determines the direction of a particular movement, and thus the organization of the action system. Each sequence of muscle contractions is determined by the sequential firing of motorneurons in the C.N.S. So we find that, not only language but all behavior is determined by the sequential order of neuromuscular events (Lashley 1951). Now the question arises whether we can find a distinction, similar to the one we found in communication, between behavioral systems that are based on fixed, genetically preprogrammed neuromuscular sequences and systems that allow for the recombination of these sequences. That is, whether it is possible to find species with essentially "closed" behavioral systems as opposed to species with behavioral "openness"or "flexibility".
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4.1 Inflexible behavior Broadly speaking, such a division in behavioral capacities can be made, although, of course, one should refrain from strict dichotomizations in these matters. It appears that in lower vertebrates (fish, amphibians, and reptiles) the behavioral system essentially consists of relatively stereotyped reaction patterns, in response to holistic patterns of stimulation. In contrast, mammals show a marked capacity to form new responses in reaction to specific environmental demands (e. g. Jerison 1973; Lenneberg 1967). In other words, "in the lower vertebrates one may be dealing with brain: behavior systems at the cartesian level, essentially reflex machines with few requirements for plasticity or flexibility" (Jerison 1973: 433). In lower vertebrates the individual possesses a limited set of fixed behavioral responses which are triggered by the appropriate preprogrammed stimulus patterns. A limited capacity for either stimulus-stimulus pairing or stimulus-response pairing (i. e. classical or operant conditioning) seems to be possible under very strict experimental conditions (McPhail 1982). Fine-tuning of the behavioral repertoire to the particular environmental circumstances through the invention of new action-patterns, is, however, not possible. Pattern perception is poorly developed so that an extremely large array of stimulus configurations may serve to elicit a certain behavioral sequence, and there is little specificity in stimulability. However, the motor responses are all highly predictable and are based on relatively simple neuromuscular correlates; thus, there is a high degree of response specificity (Lenneberg 1967). Because of the rigidity of the behavioral system in these lower forms, the individual cannot adapt its behavior to extensive changes in an unstable environment. This is so, because first, it would be very difficult to interact with such an environment on the basis of prepotent cues from certain stimulus-configurations (e. g. Jerison 1973); and second, because the genetically fixed action-patterns of the organism are likely to be adaptive only under the special environmental conditions in which they evolved. In the lower vertebrates, therefore, the adaptation of the behavioral repertoire to the environmental requirements can only be achieved by biological evolution, i. e. through natural selection of the underlying genetic material. Therefore, the reaction-time in these organisms to extensive environmental changes, will be proportional to their generationtime.
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In conclusion, in species with inflexible behavioral capacities, highly adaptive, often extremely complex behavioral patterns can evolve through natural selection, under the condition that the environmental circumstances are stable, relative to the generationtime of the species. The modifiability of these behavioral patterns remains, however, very limited. Even minor environmental changes can render them totally ineffective, and reduce their biological significance dramatically. This incapability to adjust to environmental changes, can be illustrated by the response of frogs to moving stimuli such as flies. If, by surgical intervention, the eyes of the frog are rotated in their sockets to produce inverted images, the frog never adjusts to the new situation. Instead, when presented with a moving stimulus, it persistently strikes out at a point in space appropriate to the point of stimulation as it would be mirrored on the retina of an intact eye (Sperry 1951). In other words, the frog cannot learn to invert its responses in reaction to an inverted visual space. 4.2 Flexible behavior From the discussion on inflexible behavior, it follows that an organism, which evolved the capacity actively to adjust its behavioral repertoire to the particular environmental demands, would acquire several important advantages over organisms with a genetically fixed behavioral repertoire. For such a capacity to evolve, it is not sufficient that the organism acquires more response flexibility. Complete freedom of action would lead to random behavior, which obviously is maladaptive. Therefore, additional mechanisms that ensure that this capacity for response flexibility is used effectively must evolve simultaneously. That is, effective in an evolutionary sense: ultimately enhancing the reproductive success of the genes that code for such a capacity (Dawkins 1976, 1982). From its expanded repertoire of response options, the organism must be able to select the proper response under the proper circumstances. Moreover, in dangerous situations it must still be able to act quickly. So, for a flexible behavioral system to function more effectively than a fixed behavioral system, which is essential if it is to evolve, it should incorporate the follogwing capacities: — Increased motor-control, which allows for the production of new action patterns, and thus for more response flexibility.
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— The capacity for more complex pattern perception, which is necessary to discriminate between more and more complex environmental situations, and thus allows for more appropriate responseformation. This perceptual development is closely related with the development of cognitive capacities such as categorization, crossmodal integration, concept-formation, etc. (Jerison 1973). — Elaborate pre- and post-action evaluation systems that enable the organism to select, on the basis of sensory information and previous experience, the behavioral option that matches best a system of genetically based reference standards (Young 1978). These evaluation systems function to ensure that the organism, on average, will act to promote the evolutionary success of its genetic material, and are involved in motivation and reinforcement. — Because the organism, by virtue of its behavioral flexibility, can no longer rely upon built-in reflexes for at least a part of its interactions with the environment, it has to acquire many of the automatisms necessary for survival in emergency situations by itself. Therefore, selection would promote the evolution of motivational programs that ensure that the necessary skills are acquired as soon after birth as possible, at the same time enhancing the effectiveness of behavioral flexibility. This implies that, at least during its juvenile period, the organism should invest any surplus of energy in expanding and refining its behavioral repertoire, thus adapting it to the prevailing environmental circumstances. This is best achieved if the organism is programmed to seek high arousal evoking situations whenever surplus energy is available, and to seek arousal-reducing situations as soon as an emergency occurs or as the surplus energy is exhausted (van der Molen 1983). Accordingly, behavioral activities that usually are described as 'curiosity' or 'play' can be explained. From these conditions, that should be met if anything like behavioral flexibility is to be favored by natural selection, it follows that the emergence of this capacity must have been correlated with a substantial increase of the information-processing capacity of the C.N.S. It also follows, that the capacity for behavioral flexibility will only be selected for in those parts of the behavioral system where a more flexible interaction with the environment immediately pays off. In other words, the behavioral system of every higher (mammalian) organism will consist of a species-specific mixture of fixed and flexible behaviors. This mixture is directly related to the environmental niche of the species.
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4.3 Organizational principles of behavioral flexibility To recapitulate, the behavior of the lowest vertebrates can be characterized as consisting of a few, functionally complete, fixed action patterns, which are triggered by the appropriate stimulus configurations. In the higher forms a multitude of patterns emerges: "The patterns are no longer indivisible units but may be thought of as consisting of constituents or behavioral components. They are the building stones for the complex patterns which are available and which enter in a great many combinations, thus producing the infinity of tasks for which a higher animal can be trained" (Lenneberg 1967: 12). According to this statement, behavioral flexibility consists of the capacity to combine and recombine a limited number of behavioral units into a multitude of new behavioral patterns. More recently, Peters (1981) elaborated on this point. She proposed that flexible behavior may have been derived from fixed behavior in an evolutionary trend, in which the fixed action patterns of earlier and simpler organisms are differentiated into component units which can then be recombined in variable ways in descendant, more complex organisms (Peters 1981: 684). In section 4, it was argued that each behavioral pattern is characterized by a particular sequence of neuromuscular events. Now, it appears that behavioral flexibility derives from the capacity to differentiate these functionally complete sequences into constituent, in first instance still functionally significant, sequences. Under continuing selection pressures for more refined motor control, these latter sequences can be further differentiated into smaller, functionally insignificant constituents, finally reaching the most elementary units of motor behavior, or neuromuscular events. These constituent sequences or units, then, can be recombined to form new functionally complete sequences, following strict rules of recombination. The analogy with the organization of language is striking. In fact, it is Peters' (1981) hypothesis that the capacity for behavioral flexibility is basd on syntactic rules for the recombination of behavioral units on several levels (duality of patterning), which are very similar to the syntactic rules which govern human language: "Inflexible behavior may be compared to a sentence which, once started, must be completed in an unvarying way, while flexible behavior allows for a rearrangement and substitution of the parts to form 'new' sentences" (Peters 1981: 684).
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Since behavioral flexibility is phylogenetically much older than human language, we may rephrase the argument, and postulate that the syntactic rules of language are derived from the syntactic rules which govern all flexible behavior. In doing so, we join Lenneberg who said. "In the mechanisms of language we find a natural extension of very general principles of organization of behavior, which are biologically adapted to a highly specific ethological function" (Lenneberg 1967: 324). In addition, he has come to the conclusion that "the transformational principle in language appears to be virtually identical with the cognitive principles that underly the ability to categorize both the patterns of the environment and the patterns produced by our own movements" (Lenneberg 1967: 325), which was one of the conditions for the evolutionary success of behavioral flexibility as described in section 4.2. In conclusion, human language seems to be based on the same organizational principles which underly the capacity for all behavioral flexibility in the higher vertebrates. In language these principles appear, however, in highly specizalized forms, which are only observed in humans. No other species uses syntactic principles in natural communication, while it may readily use similar principles in voluntary movement. Even extensive training of chimpanzees, our closest living relatives, in the use of artificial syntactic communication systems, has provided no compelling evidence for their ability to use even the simplest of syntactical rules in communication (e. g. Terrace 1980; Terrace and Bever 1976). On the contrary, it is argued that chimpanzees fail to produce, in communication, the novel constituent structures from which internalized syntactical rules can be inferred (Fodor, Bever and Garret 1975).
5.1 The phylogenetic development of brain and behavior In previous sections it was argued, that in the evolutionary history of the vertebrate behavioral system a trend exists towards increasing freedom for the individual to match its behavioral responses to the particular environmental circumstances that it encounters during its life. This trend is correlated with an increasing capacity to integrate and categorize perceptive patterns, and seems to be based on an increasing capacity for the syntactic production and recombination of neuromuscular sequences.
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Comparative studies on extant species suggest that this capacity for behavioral flexibility is one of the major characteristics that differentiate the mammals from other vertebrate classes (Jerison 1973). Behavior is a consequence of brain activity. It makes therefore good sense to look for differences in brain organization between mammals and their phylogenetic ancestors, reptiles in particular, which can be correlated to the above-mentioned differences in behavioral organization. The feature that most strikingly differentiates the mammalian from the nonmammalian brain, is the possession of a greatly expanded, six-layered neocortex. Apart from this expansion of neocortical tissue and the corresponding distortion of the phylogenetically older allocortex (limbic cortex), the basic organization of the forebrain is the same in mammals as it was in reptiles, their direct phylogenetic ancestors (McPhail 1982). The phylogenetic development of the neocortex is accompanied by the process of encephalization of function, i. e. relatively greater role of the neocortex in various behavioral functions (Ganong 1979). In this process, low-level, phylogenetically older brainsystems become controlled and dominated by the new neocortical structures, and are incorporated in the generation of new functions determined by these neocortical systems, which they influence in turn (Locke 1978). Together with the neocortex the pyramidal system emerges, which also is present only in mammals, and reaches its greatest development in the primates (Ganong 1979). It connects the pyramidal cells in the motor cortex with the motor neurons of the spinal cord, and mediates the cortical control over voluntary, skilled and fine movements. It is superimposed upon the phylogenetically older extra-pyramidal pathway which is associated with grosser movements, automatic postural adjustments and stereotyped responses (Ganong 1979; Villee, Walker and Barnes 1973). The primitive allocortex and the neighboring juxtallocortex together make up the limbic cortex, which is the phylogenetically oldest part of the cerebral cortex (Ganong 1979). Together with the associated subcortical regions and brainstem nuclei (e. g. hypothalamus, amygdala, etc.), it forms the limbic system (Robinson 1976). The limbic system governs the programming of holistic patterned, species-typical hehaviors, and cannot subserve the kind of fine tuning of complex motor activity that only neocortical mediation can provide (MacLean 1973; Steklis and Hamad 1976). In addition, the limbic system is intimately concerned with adaptive and motiva-
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tional behaviors (MacLean 1958). Thus, it plays a vital role in supplying motivation for volitional acts and reinforcement in learning. In lower animals it generates complete, relatively stereotyped, species-specific behavior patterns, such as organized aggression, fighting, fear reactions, defensive and escape responses, sexual behavior, feeding, drinking, and communication (Robinson 1976). All these behaviors are directly concerned with survival and reproduction, which suggests that the limbic system plays a crucial part in the genetic control over all adaptive behavior. For example, in lower animals courtship and successful mating can occur without previous sexual experience, indicating a direct genetic control. In primates, however, learning plays an increasing role, and in humans the sexual functions have become extensively encephalized and conditioned by social and psychic factors (Ganong 1979). In short, the limbic system mediates the genetic control over the behavioral activities of the individual; either direct, through the generation of genetically preprogrammed, species-specific behavior patterns, or indirect, by controlling motivation and reinforcement. With advancing phylogeny, more functions previously governed by the limbic system become encephalized, and acquire the characteristics of neocortical, volitional control. This development is closely related to the fact that, both with advancing phylogeny and with increasing brain volume, the amount of limbic cortex decreases progressively relative to the amount of neocortex (McPhail 1982). (See Ganong 1979: 184; MacLean 1954: 29). In conclusion, the phylogenetic development of the neocortex runs parallel to that of behavioral flexibility. Moreover, the progressive encephalization of behavioral functions is invariably accompanied by more flexibility in the performance of these functions. Finally, volitional control and fine tuning of complex motor activity is mediated exclusively by the neocortical motor areas and the connecting pyramidal system. All these facts indicate that the neocortex is intimately related to the organization of behavioral flexibility. 5.2 The ontogenetic development of brain and behavior In humans the brain undergoes a very rapid weight increase during the postnatal period. In the first two years of life there is roughly a 350% weight increase, whereas at the end of the next ten years
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the weight gain is merely thirty-five percent. By about age fourteen the brain has reached its adult weight and no further increases are registered. For chimpanzees this increase is much slower; during the first two years about fifty percent. This difference is related to the fact that at birth man's brain weight is only twenty-four percent of the adult value, whereas the chimpanzee starts life with a brain that already weighs sixty percent of its final value (Lenneberg 1967). The rapid increase in cortical volume during maturation is not due to an increase in the number of neurons, but to an increase in the size of each neuron with respect to dendritic growth, and an increase in number of neuroglial cells. Thus, as the cortex expands with advancing age, the neurodensity decreases, the amount of neuroglial cells increases, and so does the amount of connectivity between neurons by virtue of increased dendritic branching (Lenneberg 1967). (See Lenneberg 1967: 160-161). In this context it is significant to note the fact that humans have an average of only 1.25 times the number of cortical neurons as chimpanzees, even though they have four times the amount of cortex (Holloway 1966). A substantial increase in dendritic branching in the cortex of humans relative to chimpanzees may be inferred. The major change that evidently occurs during the period of expansion of the neocortex, probably both in human maturation and hominid evolution, is the increased interconnection of neurons. In summary, the ontogenetic development of the neocortex is characterized by an increase in both the structural and the metabolic potential for each neuron to participate in frequent and varying firing patterns. A similar trend is likely in the development of the neocortex during hominid evolution. Lenneberg (1967: 166 — 168) reviewed data on other parameters of brain maturation, i. e. changes in chemical composition and electrophysiological changes, and reached the conclusion that these factors show a high correlation with the above-mentioned structural changes, He concluded that as the brain matures, the growing infant successively attains various developmental milestones in its behavior, such as sitting, walking, and joining words into phrases. Each of these milestones is thought of as the most outstanding characteristic of a developmental stage, and is accompanied by a whole spectrum of sensory and motor development (see Lenneberg 1967: 169).
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The following passage offers a more detailed description of the behavioral development of the human infant in relation to cerebral maturation: "With maturation the neonate begins to organize the perceptually available stimuli surrounding him and also to organize the movements of his muscles. Sensory data become grouped into as yet undifferentiated, global classes of gross patterns, and these subsequently become differentiated into more specific patterns. Both the perceived patterns and the self-produced patterns of movements become organized or grouped in functional categories, and hierarchies of categories. Members of a particular category are functionally equivalent because they either elicit an identical response or they serve one and the same function within the overall structure of a particular behavior pattern. It is these general principles of differentiation and categorization that appear in specialized form in verbal behavior. They influence the organization of perceived material as well as the organization of motor output" (Lenneberg 1967: 325). In fact, this passage gives a most elaborate description of a developing capacity for behavioral flexibility, complete with its perceptive, productive, and cognitive aspects. In conclusion, it follows that the develoment of behavioral flexibility is closely correlated with the maturation of the neocortex, as expressed in the amount of connectivity between its neurons. This correlation with connectivity between, rather than number of, neurons, is just what one would expect, given the hypothesis that behavioral flexibility consists of the syntactical recombination of a limited set of elements into a virtually unlimited set of patterns (see section 4.3). 5.3 Behavioral flexibility and the neocortex, general conclusions Both the phylogenetic and the ontogenetic development of the neocortex appear to coincide with the development of behavioral flexibility. In particular, the amount of connectivity between the cortical neurons seems to determine both the scope and degree of behavioral flexibility. Accordingly, I propose a causal relationship between neocortex and behavioral flexibility, in which the specific neural organization of the neocortex is responsible for the capacity to break up holistic patterns of neurological activity into component units on several hierarchical levels, joined with the capacity to
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recombine these units, following syntactic rules, into an infinite variety of new patterns. Crucial in this respect is the capacity for each cortical neuron to partake in a wide variety of firing patterns, which capacity increases as the connectivity between neurons increases. This capacity for unlimited, syntactical recombination is basic to all aspects of behavioral flexibility, and plays a vital role in freeing universal information-processing capacities, such as integration, categorization and differentiation, from fixed, genetic programs. In short, syntactic recombination appears to be the basic mechanism in the neocortical processing of information. As is the case for all encephalized behavioral functions, the faculty for communication acquires flexibility or syntactical 'openness' as it is reorganized under neocortical control, which is an exclusive feature of the human species.
6. Implications for the evolution of human language If the above argument would prove to be correct, then the structural characteristics of human language would reflect the general principles of information processing by the neocortex; i. e., universal grammar would be determined by the neurological organization of the neocortex. However, to explain the origin of human language, the gap must be filled between the chimpanzee, who has no neocortical control over facial expression or vocal apparatus (Myers 1976), who lacks a syntactical communication system — and who, in these respects, probably reflects the initial state in hominid evolution — and the first speaking hominids. 6.1 Prerequisites for human speech If one is to retrace the origin of human vocal language, starting from a distant ancestor with chimpanzee-like communicative abilities, then the evolutionary development of at least three major, more or less independent neural reorganizations should be accounted for. a) It has already been observed that the vocal apparatus of the chimpanzee is, as it is in all nonhuman primates, predominantly under control of the limbic system. Therefore chimpanzees lack the
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requisite flexibility and freedom of affect to engage in a humanlike form of vocal communication. At some stage in hominid evolution the control over the vocal apparatus must have become encephalized; i. e., it must have come under cortical control, as it is in Homo sapiens. This implies an extensive neural reorganization, complete with the emergence of new cortical projection areas and the related afferent and efferent pathways. Such a complex reorganization cannot be a matter of pure coincidence, it must have evolved under strong selection pressures (Dawkins 1982; Dobzhansky et al. 1977). In this respect it should be noted that the nonhuman primate communication system is highly effective as an alarm system just because of its affective nature (Marler 1980). A release from affect, necessary for the development of a vocal language, would reduce this effectiveness, and would have to be compensated for in evolutionary terms, b) Speech production is one of the most complex motor activities known. It is difficult to state the exact number of muscles that are involved in speech. However, considering that ordinarily the muscles of the thoracic and abdominal walls, the neck and face, the larynx, pharynx, and the oral cavity are all properly coordinated during the act of speaking, it becomes obvious that over 100 muscles must be controlled centrally. Since the passage from any one speech sound to another depends ultimately on differences in muscular adjustments, then, taking an average of about fourteen phonemes per second in normal conversation, fourteen times per second a neural command must be issued to every muscle, whether to contract, relax, or maintain its tonus (Lenneberg 1967). However, the readjustment does not occur simultaneously for all muscles, but various groups of muscles have characteristic timing; some are active shortly before the acoustic onset of a phoneme, some shortly after. Thus it appears that the rate at which individual muscular events occur, throughout the speech apparatus, is of an order of magnitude of several hundred events every second. Moreover, the muscular activity associated with one phoneme is influenced by the phonemes that precede and follow it. Therefore, there is no simple relation that equates one phoneme with one pattern of muscular interaction. On the contrary, the same phoneme corresponds, in different phonemic sequences, to different motor patterns. Thus, the motor patterns that are involved in speech production, are highly complex motor configurations that extend over
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relatively long periods, such as the duration of a syllable or word (Lenneberg 1967). In short, the sequential order of neuromuscular events can only be programmed once the order of phonemes is determined. The order of phonemes, in turn, depends on the order of morphemes, which depends ultimately upon the structure of the complete sentence (see Lenneberg 1967: 107). The motor coordination for the production of an average sentence or phrase, therefore, involves several thousands of neuromuscular events, the ordering of which must be programmed in advance of its production. It is evident that speech production is an extremely complex activity, which requires far more processing capacity than any of the activities that are now under neocortical control in chimpanzees. The acquisition of vocal control by our hominid ancestors must have required a substantial prior investment in neocortical capacity. Artificial language-training experiments have revealed that chimpanzees can be taught to use and understand symbolic signs in simple forms of communication. There is, however, no convincing evidence that chimpanzees can assign a different meaning to different syntactical constructions of signs; see section 4.3. In other words, chimpanzees can be trained in the use of 'lexical semantics,' but apparently lack the necessary integration of syntactic and symbolic capacities which would enable them to handle 'syntactical semantics;' see section 3.1.1. Therefore, this latter capacity represents yet another major development in hominid evolution which must have preceded the onset of proper speech. The unfolding of language capacities in human infants also shows a development from lexical to syntactial semantics, which is related to neocortical maturation (Lenneberg 1967). This fact suggests that the latter capacity requires a higher degree of connectivity in the neocortex than the former. 6.2 The developmental threshold for the evolution of speech The three points discussed above are by no means supposed to cover all the prerequisites for human speech which are not found in chimpanzees. They suffice, however, to illustrate that in hominid evolution, the capacity to use even a simple version of spoken language requires the a priori development of several extensive and
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highly complex neural reorganizations. Such complex reorganizations can evolve only through natural selection at many genetic loci; i. e., they can only be the result of gradual change, requiring several thousands of generations. In addition, each genetically based change is selected for its immediate effects on reproduction. Most changes in complex, highly adapted systems have negative effects, and are eliminated by balancing selection. Only those genetical changes, which have, under the prevailing environmental conditions, an immediate positive effect on their own reproduction, are preserved by evolution (Dawkins 1976, 1982). In short, evolution is always a matter of immediate costs and benefits (e. g. Dobzhansky et al. 1977). Since the capacity for speech requires several substantial, time-consuming evolutionary investments, any explanation of the evolution of vocal language that is based solely on the benefits derived from the use of that capacity, is confronted with an unbridgeable time-lag. Therefore, such an explanation is not valid; genes are no long-term investors. Thus, if one is to reconstruct the evolution of human language, one should take into consideration every aspect of hominid behavioral evolution, even if there is no direct link with communication, and the related development of the hominid brain. In such a way it is, theoretically, possible to reconstruct a gradual development of the necessary neural reorganizations, in which each step can be explained by immediate selective benefits. 6.3 Gestural communication as a precursor for human speech An important phase in the development of the prerequisite capacities for human speech, could have been the development of a gestural communication system in early hominids (Hewes 1976; Steklis and Harnad 1976). The evolutionary threshold for the development of a gestural language in hominid evolution, is much lower than for the development of a vocal language, because much less neural reorganization is necessary (Steklis and Harnad 1976). First of all, even in chimpanzees the forelimbs are under direct cortical control (e. g. Myers 1976), and they can actually be trained in the use of a wide variety of gestural signs. In early hominids, the manufacturing and use of stone tools provides evidence of even higher manipulative and conceptual skills (Holloway 1969), which is also reflected in an increased relative brain size. Therefore, a simple gestural communi-
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cation system, similar to that taught to chimpanzees, would have been well within their capacities. Once such a system would have been established, a gradual development of the capacity to attach a different meaning to different syntactical combinations of signs, would have been feasible. Finally, this development could have resulted in a true, syntactically open, gestural language. The evolution of a true gestural language would also lower the developmental threshold for the emergence of a spoken language. Indeed, an increased neocortical processing capacity, derived from elaborate manipulative control, together with the established cognitive capacities for syntactical semantics, would only leave the necessary neocortical control over the vocal apparatus to be developed. A transitory phase with the mixed use of vocalizations and gestures, could well have accounted for this development. Finally, a completely human, vocal language could have replaced the gestural language (Steklis and Harnad 1976). Supporting evidence for this theory can be found in the frequent and prior use of gestures in everyday conversation, and the early use of highly effective gestural communication by human infants, which invariably precedes the onset of speech. Another significant fact is that motor-dominance and language functions are, as a rule, co-lateralized in the same hemisphere (Steklis and Harnad 1976). References Chomsky, Noam 1980 Human language and other semiotic systems. In Thomas A. Sebeok and Jean Umiker-Sebeok (eds.), Speaking of Apes. 429—441. New York: Plenum. Dawkins, R. 1976 The Selfish Gene. Oxford: Oxford University Press. 1982 The Extended Phenotype. Oxford, Freeman. Dobzhansky, T., F. J. Ayala, G. L. Stebbins and J. W. Valentine 1977 Evolution. San Francisco: Freeman. Fodor, J., T. Bever and M. Garret 1975 The Psychology of Language. New York: McGraw-Hill. Fouts, R. S. 1976 Comparison of sign language projects and implications for language origins. In S. R. Harnad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 589-592. New York: The New York Academy of Sciences. Ganong, W. F. 1979 The Nervous System. Los Altos, CA: Lange Med. Publ.
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Gardner, R. A. and Β. T. Gardner 1980 Comparative psychology and language acquisition. In Thomas A. Sebeok and Jean Umiker-Sebeok (eds.), Speaking of Apes. 287 — 351. New York: Plenum. Geschwind, Ν. 1970 The organization of language and the brain. Science 170. 940—944. Glasersfeld, Ε. von 1976 The development of language as purposive behavior. In S. R. Hamad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 212 — 226. New York: The New York Academy of Sciences. Hewes, Gordon W. 1976 The current status of the gestural theory of language origin. In S. R. Hamad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 482-505. New York: The New York Academy of Sciences. Hockett, Charles F. and S. A. Altmann 1969 A note on design features. In Thomas A. Sebeok (ed.), Animal Communication. 61 — 72. Bloomington, Ind.: Indiana University Press. Holloway, R. L. 1966 Cranial capacity, neural reorganization, and hominid evolution: A search for more suitable parameters. American Anthropologist 68. 103-121. 1969 Culture: A human domain. Current Anthropology 10-4. 395—412. Jerison, Harry J. 1973 Evolution of the Brain and Intelligence. New York, Academic Press. 1983 Evolutionary neurobiology and the origin of language as a cognitive adaptation. Paper delivered at the XIth ICAES, Vancouver, August 1983. (In this volume). Lamendella, J. T. 1976 Relations between the ontogeny and phylogeny of language: A neorecapitulanionist view. In S. R. Hamad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 396-413. New York: The New York Academy of Sciences. Lashley, K. S. 1951 The problem of serial order in behavior. In L. A. Jeffres (ed.), Cerebral Mechanisms in Behavior. 112 — 136. The Hixon Symposium. New York: Wiley. Lenneberg, Eric H. 1967 Biological Foundations of Language. New York: Wiley. Limber, J. 1980 Language in child and chimp? In Thomas A. Sebeok and Jean UmikerSebeok (eds.), Speaking of Apes. 197—221. New York: Plenum. Locke, S. 1978 Motor programming and language behavior. In G. A. Miller and Ε. H. Lenneberg (eds.), Psychology and Biology of Language and Thought. 113 — 118. New York: Academic Press.
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MacLean, P. D. 1954 The limbic system and its hippocampal formation. Journal of Neurosurgery 11. 29. 1958 The limbic system with respect to selfpreservation and the preservation of the species. Journal of Nervous and Mental Disorders 127. 1 — 11. 1973 A triune concept of the brain and behavior. In T. J. Boag and D. Campbell (eds.), The Clarence M. Hincks Memorial Lecture, 1, 6—66. Toronto: Toronto University Press. MacPhail, Ε. M. 1982 Brain and Intelligence in Vertebrates. Oxford: Clarendon. Malmi, W. A. 1980 Chimpanzees and language evolution. In Thomas A. Sebeok and Jean Umiker-Sebeok (eds.), Speaking of Apes. 191-197. New York: Plenum. Marler, P. 1975 On the origin of speech from animal sounds. In J. F. Kavanagh and J. E. Cutting (eds.), The Role of Speech in Language. 11 — 37. Cambridge, MA: M.I.T. Press. 1980 Primate vocalization: Affective or symbolic? In Thomas A. Sebeok and Jean Umiker-Sebeok (eds.), Speaking of Apes. 221—231. New York: Plenum. Maruszewski, M. 1975 Language Communication and the Brain. The Hague: Mouton. Molen, P. P. van der 1983 The Evolutionary Stability of a Bi-Stable System of Emotions in Species with an Open-Ended Capacity for learning. Groningen: Heymans Bulletins, HB-83-680-EX. Moynihan, M. 1970 Control, suppression, decay, disappearance and replacement of displays. Journal of Theoretical Biology 29. 85 — 112. Myers, R. E. 1976 Comparative neurology of vocalization and speech: Proof of a dichotomy. In S. R. Harnad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 732-745. New York: The New York Academy of Sciences. Peters, Ε. H. 1981 Differentiation and syntax in the evolution of behavioral flexibility. Current Anthropology 22-6. 683 — 686. Robinson, B. W. 1976 Limbic influences on human speech. In S. R. Harnad, H. D. Steklis and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 761 — 772. New York: The New York Academy of Sciences. Rumbaugh, Duane M. 1980 Language behavior of apes. In Thomas A. Sebeok and Jean UmikerSebeok (eds.), Speaking of Apes. 231—259. New York: Plenum.
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Sperry, R. W. 1951 Mechanisms of neural maturation. In S. S. Stevens (ed.), Handbook of Experimental Psychology. 236 — 280. New York: Wiley. Steklis, Horst D. and Steven R. Harnad 1976 From hand to mouth: Some critical stages in the evolution of language. In H. D. Steklis, S. R. Harnad and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 445—4556. New York: The New York Academy of Sciences. Terrace, H. S. 1980 Is problem-solving language? In Thomas A. Sebeok, and Jean UmikerSebeok (eds.), Speaking of Apes. 385—404. New York: Plenum. Terrace, H. S. and T. G. Bever 1976 What might be learned from the chimpanzee? In H. D. Steklis, S. R. Harnad and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 579 — 589. New York: The New York Academy of Sciences. Villee, C. Α., W. F. Walker and R. D. Barnes 1973 General Zoology. Philadelphia: Saunders. Wind, Jan 1976 Phylogeny of the human vocal tract. In H. D. Steklis, S. R. Harnad and J. Lancaster (eds.), Origins and Evolution of Language and Speech. Annals of the New York Academy of Sciences, Vol. 280. 612—631. New York: The New York Academy of Sciences. Winter, Willem de 1984 Biological and cultural evolution: Different manifestations of the same principle. A. systems-theoretical approach. Journal of Human Evolution 13-1. 61-70. Young, J. Z. 1978 Programs of the Brain. Oxford: Oxford University Press.
Index
Ability to communicate 95 Accusative 123, 130 Acoustic cues 22 Acoustic cues, discrimination 31 Adaptation 3 Adaptations 4, 253 AER; see Auditory evoked response Affect 240, 241, 263 Agglutinating languages 130 Akkadian 219, 224, 225 Allocortex 258 Allomorphs 222 Allophones 222 Alphabet 1 0 1 - 1 0 2 —, phonetic 103 American Sign Language of the Deaf 76, 7 9 - 8 1 , 108, 150, 156 Amoeba 119 Animal communication 248 — 250 Animals 105, 107, 229, 255, 256, 259 Anterior cingulate gyrus 49, 53 Ape language 7 9 - 8 0 , 86 Apes 6 7 - 7 0 , 75, 8 1 - 8 2 , 9 7 - 9 8 , 150, 157, 1 6 1 - 1 6 2 —, African 47, 55 —, brain size 156 Appositives 126 Arabic 122, 128, 221 Aramaic 221 Armenian 123, 132, 133 Articles 125 Articulation 24 ASL; see American Sign Language Aspect, verbal 1 2 3 - 1 2 4 Associations, cross-modal 150 Asymmetrical functioning 14 Asymmetries, hemispheric 37, 47 Auditory evoked response (AER) 14, 1 7 - 1 9 , 21, 23, 24, 2 6 - 2 9 , 32 — perception 37 — system, primate 22 - - v o c a l system 7 Australopithecines 57, 71 - 7 2 , 84,160 — 161, 165
Australopithecus 159 Auxiliaries 125 Baboons 5 1 - 5 3 , 72 Basque 195 "Baupläne" 138 Bats 91 Bayley Scales of Infant Development 26, 28 Behavioral flexibility 247, 2 5 2 - 2 5 9 , 261-262 — pattern 256 Behaviors, homologous 55 Bengali 123 Bilabial stops 17, 21 Bilateral hemisphere effects 25 Biological components, role of in language development 11 Biology, evolutionary 3 Bioprogram 240 — 241 —, kinesics 235 - , language 2 3 5 - 2 3 6 , 238 Brain lateralization 212 — organization 12, 258 — organization, biological influence on 31 — responses 27, 30 — size, apes 70 - , human 1 4 9 - 1 6 5 , 173, 265 — tissue 5 — volume 85 — waves 26, 229 — weight 259 —, asymmetries 12 —, hominid 4 —, anatomical connectivity 50 —, split 52 —size/linguistic capacity 158 Braincases 173, 178 Brains, organization of 70 Brazelton Neonatal Assessment Scale 25, 2 8 - 3 0 Broca's area 50, 57, 150, 158
272
Index
Call perception 46 — production 46, 48 — systems 239 Calls, contact 40 —, coo 51 —, hominid 237 —, monkey 37, 252 —, monkey or ape 38 — 54 —, semantic quality 37 —, syntax of 45 —, synthesized 44 trill 45 —, warning 8, 41, 45, 249 Categorial discrimination 22 Cats 105 Cave dwelling 97 Caves, African 71 Celtic 123 Cenozoic hominids 224 Central Nervous System (CNS) 252 Cerebral asymmetries 12, 47 — asymmetries, acquired 53 — cortex 47, 258 — damage 13 — dominance, and handedness 54 — hemispheres 1, 30, 76 — lateralization 151, 211 — organization 54 — sulcal patterns 56 Chatelperronians 84 Chimpanzee "language" 9 Chimpanzees 40, 69, 71, 73-75, 8 1 82, 99, 116, 150-156, 241, 247, 257, 260, 262, 264, 266 —, cranial capacity 160 Chinchillas 105 Chinese 220 Clever Hans cueing effect 80 Clicks 82 CNS; see Central Nervous System Cognition, human 83 Cognitive adaptation 3 — capacity 161, 255 — features 237 — structures 93, 159 Communication, affective types 41 - , animal 3, 7 - 8 , 240 —, animal, content 38
—, as reality sharing 7 —, failures 3 —, prior to language 183 —, semantic types 41 Complexity, conceptual 114 Concepts of space and time 207 Consciousness 8 — of self, evolution of 4 Consonant release 17 — sound configurations 24 Control, manual 69 Conversational maxims 189 Correlatives 130 Cortex 157 —, anterior cingulate 49 —, somatosensory 53 Cotton-top tamarins 46 Cranial anatomy 173 — capacities 159 Creoles 239, 241 Cromagnon man 160, 162, 164 Cross-cultural research 232 — 235 — universality 235 Crying, in infants 94, 242 Cultural constraints 235 Dative 123 Deaf children 238 Declensions 123, 125, 130 Defense 71, 7 3 - 7 4 Degemination 132 Deixis 208 Development, logic of 93 - , mental 190 Dichotic listening paradigm 15 f — temporal processing procedures 23 Dimension 51 Displays 206 Distortions 187 — in speech 184 —, emotive 195 —, expressive 190 —, phonetic 184 —, syntactic 196 DNA 139-140, 148 Dogs 68, 86 Dolphins 107-108 Dreams 193, 241
Index Drift 121 Dual 123-124 Duality of patterning 250 Dutch 124-129 Evlaite 219 Ecosystem 90 Egyptian 219, 224 Electrocortical correlates 22 Electrophysiological changes 260 — responses 32 Encephalization 45, 259, 263 English 84, 123, 129 Enzymes 139 Epiglottis 173, 175-176, 179 Evolution of language, dates 160 —, biological 114 E, human 4, 116, 211 —, language 113, 211 —, logic of 93 —, of brain 46 —, of nervous system 46 —, speech 105 Explication 95—96 Facial expression 38 Feral children 239 Fetuses 85 Fire using 97 Fish 119 Foramen magnum 173, 175 Fossil record 176 Fossils 55, 67, 82, 158, 173, 178 French 120, 183-184, 188, 195, 220 Frogs 254 Frontal lobe 164 Functions, perceptual and cognitive 3 Future tense 164 Gatherers 164 Gender 123 Gene pool 248 Genes 116-117, 145-146, 254, 265 — and brain 140 — and language 140, 236 Geneticists 114 Genitive 123, 194 German 120, 122, 123-123, 129, 195
273
Germanic 124 Gestural language 69, 265 — 266 — language origin 228 Gesture before language 227 — language, preverbal 197 Gestures 67, 230 —, cultural constants 234 —, during communication 74 —, oral 184-185 —, prelinguistic 205 — ,prosodic 185 — 186 —, syntactic 187 —, translating 233 Gesturing, articulatory 186 —, semantic 188, 197 Glossogenetics 67, 242 Glottis 185 Glotto-chronology 220 Glottogenesis 80, 84, 205 Glottogonic studies 80 Gorillas 69, 75, 247 Gothic 124-125 Grammar, comparative 219 —, universal, meaning 250 Grammatical categories 126 Greek 132, 223 Grooming 75 Gyri 150 Hand-eye coordination 75 Handedness 76 HAS; see High Amplitude Sucking Head turning paradigm 21 Heart Rate (HR) 20 Hebrew 219, 2 2 1 - 2 2 4 Hemidecortication 13 Hemiplegia 14 Hemisphere differences 27 — responses 26 —, left 2 4 - 2 5 , 5 0 - 5 1 , 53, 76, 2 1 2 213, 249 - , right 18, 198, 2 1 1 - 2 1 3 Hemispheres, left (T3)/right(T4) 23 - , left/right 1 2 - 1 4 , 5 1 - 5 2 Hierarchy, implicational 95 Hieroglyphics 225 High Amplitude Sucking (HAS) 1 9 - 2 0 Hippocampus 5
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Index
Hittite 122 Holistic pattern recognition 106 — 107 Hominids 5, 7, 55, 72 — .cognitive processes 55 - , dates 82 —, defense 67 —, early 4, 265 —, language capacity 159 —, vocal system 56 Homo erectus 82, 160, 162-165, 173 — habilis 160-162 — sapiens 75, 160, 164-165, 173, 263 — sapiens sapiens 73, 82, 140 Homology 55 HR; see Heart Rate Human cognition 207 — development, dates 98 — language, characteristics of 102 — speech 38 Humanity, redefined 150 Humans 97 Hungarian 183-184, 195 Hunter-gatherers 71 Hunters 71, 81, 1 6 3 - 1 6 4 Hyperboles 192 Icelandic languages 234 Icon, linguistic 212 Iconic code 183 — signs 196 Iconicity 81, 208 - , linguistic 205, 213 —, meaning 213 —, syntactic 215 —, visual 211 - , vocal 211 Icons 211 Illiterates 104 Images, visual 213 Indo-Aryan 122 Indo-European 120-126, 128-132, 146, 219 Indo-European, pre-proto; dates 179 Infants 67, 74, 85, 93, 240, 261, 264, 266 Inferior parietal association area 150 Infixes 124 Innate components 21 Inner speech 83
Intelligence 97, 238 Intelligence, human 152, 164 Intonation pattern 209 Irish 132 Japanese languages 234 — 235 Japanese macaque 40, 44—45, 48, 51 Kabardian (Caucasian language) 180 Kinesics 205, 208, 227, 229, 231 LAN A project 81, 86 Langage 190 Language abilities, innate 32 — ability 12, 97 — acquisition 12, 25, 127-131, 188, 236-237 — Acquisition Device (LAD) 237 — acquisition, children 159, 161 — 163 —, disruption of 13 — and gesture 232 — and kinesics, synchronous acquisition 231 — and speech, difference 54 — capacity 247 — change, earlier acquired features 131 — evolution, meaning 113 — performance, high 30 —, low 30 —, prediction of 28 —, adaption 4 —, and cognitive maps 5 —, as response to selection pressures 4 —, biological basis of 114 — .constructed 81 —, definition 68 —, evolution 265 —, genetic basis of 118 — 119 —, human 3, 249 —, origin of 3, 37 —, as gesture 38 —, gestural models 56 —, theories 54—57 —, vocalist models 56 —, semiotic model of 205 —, sound structure of 98 —, syntax 257 Languages, analytical 127
Index
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—, progress 84 whistled 108 Langue 190 Laryngeal pulsing 16 Laryngeal 133-123, 128 Larynx 173, 175, 178-179 Lateralization 14, 25, 50 — 51 Lateralization of brain functions 12 Latin 124, 132, 220 Learning 97, 259 - , pre-natal 79, 84 Lesions 49, 50, 53 - , bilateral 50 left-sided 50 —, right-sided 50 Levels of explanation 143 Lexicon, open 68 Limbic cortex 49, 258, 259
Monkeys 107, 150, 157 —, brain size 156 —, old world 55 - , Rhesus 2 1 - 2 2 , 43, 4 8 - 5 3 , 249 Monosyllabicity 220 Monotreme 119 Mood 124 Morphemes 197, 264 Morphological changes 123 Morphology 123, 125, 130, 138-139 Mothers 7 4 - 7 5 , 84, 229, 238 Moths 91 Motoneurones 50 Mourning 229 Multivariate procedures 23 Mutations 145 Mutations, random 116
— nuclei 151 — system 259 Linguistic act 186 — capacities 102, 161 — drift 121 Linguuistics 147 Linguists 83 Locomotion 73 Lower Paleolithic 85
Natural language 86 - languages 83 - selection 115-116, 253 Nature vs. nurture 85 Neanderthal 84, 173-176 Neocortex 4 9 - 5 0 , 149, 151-152, 258, 259, 260, 261, 262, 264 Neocortical mechanisms, role in human language 38 Neonates 8 4 - 8 5 , 94, 261 Neoteny 117 Neural lesions 48 Neurobiological analysis 47 Neurobiology 3 Neuroelectrical correlates 23 Neuronal interconnect!vity 151 Neurons 154-155, 260, 261 Nouns 124-126
Mammals 68, 119, 253, 255, 258 Man, as social predator 5 — 7 Manual preference 53 Mapping 6 — 7 Mapping, as neural activity 4 Marsupial 119 McCarthy Scales of Children's Abilities 26 f, 29 Meat-eating 76 Memory, short term 6 Metaphors 189-190, 193, 197-198, 211-212
— , grammatical 193 Misuse of terms 142 Monkey food calls 43 — grunts 42 — screams 43 - , Goeldi's 45 - , squirrel 40, 47, 49, 50 - , vervet 4 1 - 4 2 , 48
Obstetric Complications Scale 25, 28-30 Old English 225 - French 120 Onomatopoeia 214, 236 Ontogeny 96, 117, 138, 235, 2 4 1 - 2 4 2 Optative 1 2 3 - 1 2 4 Orang-utans 75, 150 PA; see Place of Articulation Pakistani-Urdu languages 234
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Index
Palate 173, 176 Paleocortex 5 Paleocortical limbic structures 38 Paleontologists 115 Palestine 178 Parataxis 125 Part-whole analysis 96 Participial phrase 126 Peabody Picture Vocabulary Test 26 f, 29 Pedomoprhosis 121, 133, 137-139, 145-148 Pedomorphosis, definition 137 Perception 210 — of complex patterns 255 —, categorical 44 —, color 154 Perceptual constancy 24 — theories 104 Periphrasis 130 Pharynx 173, 175-176, 179, 185 Phonation 48, 50 Phoneme categories 19 — 20 — identification task 18 - , meaning 101-102 Phonemes 79, 197, 2 6 3 - 2 6 4 —, acoustic 103 —, articulatory 103 —, as linguistic units 101 —, as perceptual units 105 —, perceptual 104 - , reality of 223 Phonemic cues 22 — organization 98 — speech 179 — vowels 180 Phonemicization 83 Phonemicized speech 82 Phylogeny 55, 119, 128, 138, 222, 235, 241-242 —, hominid 55 Pinna 11 Place of Articulation (PA) 11, 2 2 - 2 5 , 32 Plants 90 Playback of recorded vocalizations 39 — 46 Pleistocene 71, 84, 173, 176 Pleistocene, mid 174
Pluralistic approach 116 Polysyllabicity 220 Pongids 76 Prague Linguistic Circle 195 Prehistory of languages 219 Prelinguistic features 237 Prepositions 125 Preverbal utterances of children 195 Primates 3, 6 7 - 6 8 , 73, 151, 155 —, non-human 21 Primordial speech 57 Principal components-analysis of variance procedure 27 Pronouns, personal 124 — 125 Prosimeans 155 Proto-Afro-Asiatic 220 - - g r a m m a r 183 --Indo-European 219 —language 69, 8 1 - 8 2 , 85, 121, 197 —-langugage, gestural 75 —Semitic 220 --Sino-Tibetan 179 Protolinguistic 190 Proxemics 205, 208 Psychology 93 Pygmy marmoset 40, 45 Reading 104 Reduplication 124 Reference, environments 150 Reflexes 255 Regression models 29 Relative clauses 126 Reptiles 119 Responsiveness 25 Rhinencephalon 5 Rhodesian skull 176 Right-handed 76 Romance languages 122—124, 220 Rumanian 195 Russian 123 Sandhi 219, 221 Sanskrit 126, 198, 219, 2 2 1 - 2 2 4 Scent marking system 4 — 5 Seal 119 Self-consciousness 8 --recognition 150
Index Semantic extension 190 — transfers 189 Semantics 207 Semiotics, meaning 213 Semitic languages 219 Sensorimotor areas 152 Sensory construction 152 — differentiation 152 Sentence intonation 196 — stress 196 Sentences, complex 125 —, one-word 192 Sequencing 252, 256 Shock avoidance paradigm 21 Sign language 38, 54, 67, 6 9 - 7 0 , 238 —, apes 98, 156 Signalling system 205 Signals, environmental 206 Signs, iconic 211 —, prosodic 197 —, segmental 197 Skhul V skull 178 Skulls, fossil 175 —, hominid 224 —, human 173 — 174 Slavic 123-124 Speech act 186 Soft palate 173, 175, 178 Sonar 91 Sound spectograph 39, 104 — spectrograms 103 — 104 --meaning relationship 214 --symbolism 83, 214, 236 Sounds, musical 15 —, phonetic 155 Spanish 120 Spatial information 6 — organization 207 Specialization, hemispheric 51 — 52 Speech capacity 54 — disabilities, inherited 119 — discrimination abilities 11 — of children 196 — perception 101, 105 — abilities, neonates 25 —, infants 31 — production 158, 178 — sounds 127
—, synthesized and natural 20 —, voicing 21 - , ability 97 —, emotive 184 —, phonemicized 85 Stem, invariable 124 Stimuli, speech and nonspeech 14 f Stone-tipped projectiles 97 Stops, glottalized 121-122 —, voiced 121 —, voiceless 121 Subcortical areas 47 — structures 38 Subjunctive 123, 129 Subordination 126, 130, 131 Sulci 150 Sumerian 219 Superior temporal cortex 51 Survival instincts 206 Syntax 126, 130 Syntax, change 125 synthetic Theory 116 — 116, 145 System, inherent logic of 91 —, numbers 92 —, psychological 92 —, somatic 117 Systems, evolution of 90—92 —, germinal 117 Teeth 72 Temporal 21 — planum 12 — regions 18 Tense 124 Territory 205 Testability of hypotheses 9 Testing, adults 17, 23, 25, 233 - , children 14, 18 - , infants 14, 19, 2 4 - 2 5 —, Rhesus macaque monkeys 21 —, sound sequences 106 —, Spanish-speakers 20 Tests, demographic 29 —, infant development 29 —, perinatal 29 Thalamic nuclei 151 — relay nuclei 47 Tibetan 220
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278
Index
Titi monkeys 46 Tok pisin 84 Tool-making 86 Tools 68, 71, 7 5 - 7 6 , 82, 84, 9 6 - 9 7 , 99, 149-150, 156, 159-161, 265 Toque macaques 43 Transfer features 190 Transfers, grammatical 193 —, of word categories 194 - , semantic 190-192 Triangulation procedure 55 Utterances, performative 186 Verb, compound 129 Verbs 125-126 Vision 9 1 - 9 2 —, primate 47 Vocal ability 99 - cords 175-176 - learning ability 48 - tract 11, 67, 82, 108, 252 Vocalization 67, 74
—, inhibition of 74, 76 —, learned 150 Voice-Onset-Time (VOT) 11, 2 5 - 2 6 , 32 Voiced — voiceless 21 VOT; see Voice-Onset-Time Vowel production 179 Vowels 122, 127 —, neutral 173 —, phonemic 173 - , velar 193 Weapons 6 7 - 6 8 , 7 0 - 7 7 Wernicke's area 12, 50, 57 Word order 125, 131, 187, 215 — Order, fixed 126 Writing 102, 2 2 0 - 2 2 1 —, consonants 103 —, vowels 103 Yerkish 81 Yiddish 195
16-21,