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A SE A O F G L A S S
The publisher gratefully acknowledges the generous support of the General Endowment Fund of the University of California Press Foundation.
A SEA of
GLAS S Searching for the Blaschkas’ Fragile Legacy in an Ocean at Risk drew harvell f oreword by harry w. greene
university of calif ornia press
orga n ism s a n d en v iro n m en ts Harry W. Greene, Consulting Editor
In memory of my brother,
richard k. harvell, who first inspired my interest in oceans, wild places, and art, and continues to remind me to follow my heart
Foreword by Harry W. Greene
1. I N T R O D U C T I O N The Quest for the Living Blaschka Animals
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2. ANEMONES AN D CORALS Rooted Lives of At-Risk Animals
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3. JELLYFISH The Rise of the Medusa
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4. WORMS Ecosystem Engineers Undercover
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5. SEA SLUGS Fire Stealers of the Deep
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CONTENTS
6. O C T O P US A N D S Q U I D Shape-Shifters under Pressure
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7. SEA STARS Keystone Species in Glass
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8. THE VOYAGE OF OUR BLASCHKA BIODIVERSIT Y
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Acknowledgments
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Appendix: A Primer on the Blaschka Tree of Life
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References
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List of Illustrations
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Index
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F OREWORD
A SEA OF GLASS: Searching for the Blaschkas’ Fragile Legacy in
an Ocean at Risk is the thirteenth volume in the University of California Press’s series Organisms and Environments, whose unifying themes are the diversity of plants and animals, the ways they interact with each other and their surroundings, and the implications of those relationships for science and society. We seek books that promote unusual, even unexpected connections among seemingly disparate topics and that are distinguished by the unique talents and perspectives of their authors. Previous volumes have spanned topics as diverse as Baja California reptiles and grassland ecology, but none of them have directly addressed the marine realm. Drew Harvell’s A Sea of Glass is a love story about oceans—those watery kingdoms that cover almost three-quarters of the Earth’s surface (deserts amount to only about a tenth)—and about soft, squishy critters—jellies, anemones, tubeworms, and others even less familiar to most of us; sea slugs and their better known molluscan cousins, the squid, octopuses, and cuttlefish; and sea stars, our own closest relatives among invertebrates. A Sea of Glass is also the tale of three superbly talented naturalists, the author herself and a couple of nineteenth-century Bohemian glassblowers. Through vibrant prose we accompany Drew into the marine
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realm, among the tentacled anemones and shape-shifting octopi in their cold, sometimes murky environs. Through her global travels and dives, we follow two distinctive yet obviously connected threads, the biology of those salt-water invertebrates that also fascinated the Blaschkas, and the fate of marine life on a planet increasingly threatened by the effects of human dominance. A third thread, the blurring of boundaries between science and art, runs through it all. A Sea of Glass spins together the pieces of this distinguished biologist’s career as researcher, conservation activist, and teacher. Her scientific work focuses on the ecology and evolution of coral resistance to disease—corals, as you will soon learn, are actually animals, related to anemones—and most pressingly, the impacts of a warming climate on coral reef ecosystems. To better understand these problems, she uses field observations and experiments, the latest techniques of molecular biology and chemistry, and mathematical modeling; her questions and procedures have taken her from Florida’s keys to the Yucatán Peninsula, from Hawaii to Indonesia. She’s worked with the National Center for Ecological Analysis and Synthesis and promoted coral reef research and restoration at the World Bank. And here in this volume, sailing and diving with Drew the veteran teacher, readers get a mini-course in the biology of invertebrates, a celebratory tour of those animals traditionally defined by what they don’t have and thereby taxonomically distanced from those with backbones. Invertebrates, we learn, span much of the animal tree of life, and thus shed light on our deepest ancestry. Leopold and Rudolf Blaschka, the father-son team of naturalist glassblowers, have provided what amounts to the study specimens for our class. Working from Germany, basing their efforts on illustrations in books and live animals they kept in aquaria, their
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“spineless menagerie” captivatingly portrays a wide range of marine invertebrates. Indeed, the Blaschkas’ exquisite pieces were originally commissioned for Harvard, Cornell, and other thenyoung universities because they were three-dimensional, unlike paintings, and because they retained colors, unlike the stinky, spirit-preserved corpses traditionally used as teaching material. And in fact, the structural complexity of these glass animals is so minutely portrayed that even here, on the page, they beckon as if alive. Right from the start A Sea of Glass draws us in to appreciate other life forms in their own light, with an eight-armed animal that is surely among the smartest if not the most provocative of invertebrates. The ride never lets up, and by the end we realize what’s at stake here. Underlying it all is the diversity of life itself, the astonishingly myriad ways in which creatures make their livings, under circumstances utterly foreign to us. Then there’s the health of the oceans, housing everything from sulfur-eating microbes and edible sea cucumbers to the largest mammals that have ever lived—and our ever-growing effects on water chemistry and temperature, the impact of which we cannot entirely predict but which someday might be catastrophic. Finally there are the roles of science and art in human affairs, the one providing us with facts and answers, the other affecting our values and thereby our relationships with the rest of the living world. A Sea of Glass invites us into the watery depths, to scrutinize curves and bumps of marine invertebrates, to ponder surprising combinations of color and design, and in so doing to look beyond the sharks, fishes, and whales. It invites us to learn more and thereby to care. Harry W. Greene
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1. INTRODUCTION The Quest for the Living Blaschka Animals
WHEN I FIRST MET the level gaze of two periscoped eyes and felt
suckered tentacles on my arm, I did not imagine that I would soon be holding an ink-spewing Houdini. It was otherworldly to be communing underwater with an eight-armed alien with roughly the intelligence of a cat—maybe more. For what cat can figure out how to open a child-proof bottle of Tylenol? This even eludes some people. Not surprisingly, octopus intelligence is complemented by emotions and distinct personalities. Each animal is an individual being—smart, aware, and curious. But here’s where these alchemists trump us humans: not only are they masters of shape and color, changing their appearance at will, but they have unusual powers and can taste with their tentacles and see with their lightsensitive skin. I am entranced, pulled further into this curious being’s world during one of my first dives on a quest to find the living counterparts of the glass animals created by Leopold and Rudolf Blaschka more than 150 years ago. The octopus we found in Hawaii is similar to my favorite glass piece (opposite) in the historic collection of glass sea animals housed at Cornell University, where I teach. I first saw it twenty-seven years ago, broken and dusty, its knowing eye cocked up at me, suckered tentacle stretched across the bottom of its box. I was discouraged to see the octopus so damaged, with shattered tentacles and a
Common octopus (Octopus vulgaris) in glass from the Cornell collection, restored in 2014. Photo by Gary Hodges.
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gaping hole above the eye; it looked to be beyond repair. That broken glass masterpiece is a metaphor for how some of these animals are faring in the oceans of today: like their glass counterparts, some of the living representatives are in decline. This inspired my quest to use our glass collection as a time capsule and to see how many of the living representatives we could find in today’s oceans, a quest chronicled here in A Sea of Glass. It is a continuing global journey that has taken videographer David Brown and me from the shores of Maine and Washington to far-flung locales like Indonesia, in the most diverse waters of the Coral Triangle, and the Ligurian coast of the Mediterranean. It is also a quest to bring the glass to life and show the brilliance and unusual biology of the inhabitants of the Blaschkas’ tree of life. In the 1980s, I heard from Paul Feeny, then chair of the Department of Ecology and Evolutionary Biology at Cornell, that the university had a stunning collection of glass invertebrates packed away in offsite storage. The collection had been made by the famed glass flower artists Leopold and Rudolf Blaschka. It was Paul’s idea that we should go look at the collection and think about bringing it back to campus. Paul asked Carol Yoon, then a PhD student and aspiring journalist, to come along and write up a piece about the collection for the Cornell paper. Together we made the forty-minute drive to a storage warehouse outside of Corning, New York. As we walked in the door of the huge old warehouse, I wondered why I was even there, since all we could see were boxes and boxes stacked on metal shelves that stretched endlessly across a concrete floor. As a young assistant professor trying to establish a research career studying living marine ecosystems, I really had other things to do. But once I opened the boxes, there was no turning back. I was astounded at the perfection with which so many of the invertebrate species I knew and loved had been rendered in
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glass. There before me were glass models of many species I knew well and, equally enthralling, countless ones I had never seen before: anemones, jellyfish, boxes and boxes of sea slugs—and the octopus. They were all in cardboard cartons, many wired onto their original shipping cards, with Blaschka numbers and their former taxonomic names. Some were as perfect as the day they had been made, shiny and bright; others were shattered beyond repair. I couldn’t stop looking; each box held some new wonder. In many cases it was like greeting old friends that I had once seen on some shore, long-forgotten Latin names filtering up out of the past. It was almost too much to take in at one time. Paul and Carol shared in the moment of unearthing this essentially lost treasure. Beginning with that single octopus, so perfectly made and so easily broken, I searched through all the boxes and found 569 glass animal models, acquired in 1885 by Cornell University, with the help of its first president, Andrew Dixon White, as a teaching collection (Reiling 1998). Each is an exact replica of an animal that once lived in our oceans and might still. I was enchanted that anyone could have produced such exquisite masterpieces, nearly indistinguishable from their living counterparts. That one glass octopus inspired me to begin restoration of this rare and valuable collection. When I saw its living double on a reef in Hawaii twenty-five years later, it would propel me on a worldwide quest to find more living Blaschka biodiversity. Our 150-year-old Blaschka collection is a time capsule, pulling us back to explore the biodiversity of a bygone era. This was not only a time of plentiful seas, before the Industrial Revolution, but also the age of natural history. The Blaschkas were profoundly influenced by, and initially copied, many of the spectacular anemone, jellyfish, and squid watercolors of the great naturalists Ernst Haeckel and Philip Gosse, eventually producing over 800 perfect
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glass sea creatures inhabiting many branches of the tree of life. These are the most ancient of animals on earth, animals without backbones, and they represent the fundamental body plans on our planet. Not dogs, cats, dolphins, turtles, or even fish, but rather anemones, corals, sea stars, octopuses, sea slugs, and sea squirts, animals less well known than the more common back-boned creatures and yet with big roles to play in the economy of our oceans. Some are alive and thriving to this day; others have not fared well. Some are classified as endangered in today’s oceans, and still others have been impossible to find and may even be extinct. Interestingly, the Blaschkas are not best known for their sea creatures. Historically, they are famous for their glass flowers, a major collection of which is currently housed at Harvard University. It includes over 3,000 sculptures, encompassing all major orders within the kingdom of plants. Most people don’t know that the Blaschkas created the glass menagerie of rare and mysterious sea animals first. Cornell’s collection of sea animals, acquired in 1885, may have been one of the last invertebrate collections made before they shifted to making the flowers in 1886 (Reiling 2007). The circle of Blaschka influence is vastly wider than the Harvard flower collection and the Cornell sea animal collection; Blaschka glass sea animals are shown by over fifty museums and universities across the globe and include large exhibitions in Great Britain, Ireland, Australia, Austria, the United States (at Cornell, Harvard, Tufts, and the Boston Museum of Science), Belgium, Canada, France, Italy, Germany, the Netherlands, New Zealand, Poland, and Sweden (Callaghan et al. 2013). More than 3,500 models of 800 different animals are estimated to exist. Like Cornell’s, some collections are dusty and in need of repair (Reiling 1998). Part of my work as a professor at Cornell and curator of its collection has been to sleuth out current scientific names and to restore
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the damaged models for exhibition. (An online gallery of most of Cornell’s glass invertebrates can be found at www.library.cornell .edu/blaschka-gallery. Many of the Blaschka watercolors housed in the Rakow Library at the Corning Museum of Glass are available at www.cmog.org/research/library-search/%22Blaschka%20 design%20drawings%20Marine%20invertebrates%22.) Over the past few years, in between dives inspired by the Blaschka sea animals, I have made numerous trips to the Rakow Library at the Corning Museum of Glass to explore the eight boxes of original Blaschka correspondence and watercolors in its collection. As with the glass collection, I was in turn humbled, inspired, and excited by the discovery of such a rich history; my hands shook the first time I opened those boxes. I am not by training a historian, but I felt a historian’s reverence at being able to touch the past, and excitement at the volume of material. When I leaf through the Blaschkas’ journals, letters, and watercolors, I slip back in time and feel their presence, each time learning some new detail of how and why they created something so inspiring to me. Leopold Blaschka’s background, recounted in Henri Reiling’s article (1998), offers some clues to his passion for excellence in glass. Born in 1822, he was one of three sons in a family of glassand metalworkers in the village of Böhmisch Aicha, in what is now the Czech Republic. Glassworking had been a family tradition for 300 years. Leopold’s father, Joseph, taught him the arts of glassmaking and enameling. As a boy, Leopold enjoyed natural history and displayed a talent for drawing. He was the only one of the three brothers gifted enough to be a glassworker. In 1846 Leopold married his love, Carolina Zimmermann; sadly, she died in 1850 during a cholera epidemic. This was a crushing loss, soon to be followed by another. Leopold’s beloved father died in 1852, sending him into despondence. The following year, seeking solace and
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escape, he traveled aboard the brig Pauline to North America. The boat was becalmed on the Atlantic, during which time Leopold observed several species of jellyfish, including the stunning and dangerous Portuguese man-of-war. His diary entry from this voyage, described in chapter 3, reveals that he was entranced by the forms of the jellyfish and their evening light shows of bioluminescence. This was the moment he first imagined creating a bioluminescent jellyfish spun from glass. Upon his return from the sea voyage in 1854, Leopold married Carolina Riegel and took over the management of the family business of crafting glass eyes. Rudolf, Leopold and Carolina’s only child, was born three years later, when Leopold was 35. During this time Leopold returned to his original fascination with natural history and began creating orchids in glass. These were noticed by Prince Camille de Rohan, a connoisseur of plants with a love of orchids. He requested more of Leopold’s glass orchids, some of which were inspired by strolls in the prince’s own fabulous gardens. Between 1860 and 1862, Leopold made many glass tropical plants, mostly orchids, which were mounted on artificial tree trunks. The orchids were exhibited in the prince’s palace outside Prague (Sychrov Castle is now owned by the state and open for tours). In 1863 Leopold moved to Dresden, Germany, where the prince introduced him to Heinrich Gottlieb Ludwig Reichenbach, director of the Dresden Botanical Gardens and the Dresden Natural History Museum. This was the turning point in Blaschka’s career as a glassmaker. Reichenbach was exhibiting the startling tide pool anemone lithographs from naturalist Phillip Gosse’s Actinologia Britannica (1860). Each lithographed tide pool is packed full of an impossible number of brightly colored, spotted, and striped anemones (page 22). As Leopold transitioned from making orchids to
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crafting anemones, we can see that many of his first watercolors and glass anemones are almost exact matches in posture to the Gosse lithographs. Reichenbach commissioned glass anemones and displayed them in dry aquaria as a spatial paraphrase of Gosse’s lithographs, showing idealized groups of sea animals in a natural context. Leopold’s next step marked the beginning of a period of innovation in which he would explore further branches on the tree of life. The 1872 Dresden Natural History Museum catalogue documents the transition from displaying anemones only to having forty-seven Blaschka squid models on display. The anemones and squid were the beginnings of the Blaschkas’ glass tree of life, from which would sprout a full spineless menagerie: jellyfish, sea slugs, octopuses, worms, brittle stars, sea cucumbers, and sea squirts. Only five years later, the enterprise was established, with Leopold’s now twenty-year-old son, Rudolf, as a full-time partner. Letters in the Rakow Museum archives, translated from the Old German by Henri Reiling, reveal that in 1877, Leopold ordered alcohol-preserved animals from the Naples Zoological Station on the Italian Mediterranean coast. Leopold’s correspondence reveals that soon thereafter, tanks with seawater were installed in the Blaschkas’ studio and regular shipments of living sea creatures came from suppliers in Trieste, Italy, Kiel, Germany, and Weymouth, England. In 1879, Rudolf made a field trip to upper Italy and the Adriatic (Reiling 1998). Rudolf ’s education would influence the direction in which their business developed. “I studied now very earnestly zoology and anatomy with teachers and with the help of the great Natural History library of the Imperial Academy Carol. Leopoldina which we had in Dresden that time,” we find in Henri Reiling’s translation of Rudolf ’s diary.
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Leopold and Rudolf Blaschka shaped glass by lampworking. They heated glass in an open flame (the lamp) produced by burning paraffin that melted at a low temperature. They then transformed the glass using tweezers and tongs, bending flat plate glass into different forms. They made grooves and lines in the glass with small needles positioned in a holder. They labored at a lampworker’s table with bellows and a treadle below. High temperatures could be reached by using the bellows to supply extra oxygen to the burning process in the “lamp.” The true-to-life colors on each piece were created by a combination of mixing different colors of glass or painting the glass. A stunning, technically challenging aspect of their work is the impossibly thin glass they used to craft, for example, the bell of a jellyfish. Even the expert glassworkers at the Corning Museum of Glass contend that no one today is capable of such artistry. Some part of the deeper motivation to create these masterpieces must have resided in the relationship between father and son; they shared an obsession with their work. Everyone who spent time with Leopold appears to have been charmed by him, and an afternoon of reading his correspondence reveals a kind, courtly gentleman and passionate student of natural history. He was so connected with the science of his day that he corresponded avidly with the giant of nineteenth-century marine natural history, Ernst Haeckel. Haeckel, who was widely known for his detailed, lifelike, and artistic drawings and paintings, inspired Leopold to first capture his animals in watercolor. Like their glass animals, Leopold and Rudolf ’s watercolors are mesmerizing. The Rakow Library has over 170 of them. The Blaschkas created the watercolors to
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get the pose, colors, and anatomy of each piece right before starting their work in glass. They range from simple pencil sketches, with parts crossed out and marked over, to finished works of art. The watercolors turn even lowly worms into objects of enchantment. Leopold’s watercolor of Spirorbis, a tiny feather duster worm no bigger than a ladybug, brings all the beauty and biology of the worm to light. It shows the worm pulled from its tube, revealing more than the brilliant tentacles and tiny hooks that hold it in place within the tube, and the eyespots that cue the tentacles
the Blaschkas in their dresden garden, circa 1880–1891: Leopold (right) with his second wife, carolina riegel, and their son, rudolf. Photo courtesy of the rakow research Library, corning Museum of Glass, BIB Id: 98014.
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to flicker in and out with changes in light. He shows also the eggs and the frilled, eyed larvae that are brooded by each mother worm inside her tube. I am impressed that he knew these details of this tiniest worm, holding close her brood of squirming larvae inside delicately sculpted porcelain tubes. Of course worms, even ones as brightly colored and diverse as these, aren’t for everyone. Many people are far more likely to be inspired by a startling red octopus with fierce eyes, its undulating tentacles stretched across the page, or by the possibility of one day spotting a live version of the Blaschkas’ watercolor Glaucus atlanticus, the exquisite blue-striped pelagic sea dragon (page 102), a nudibranch that feeds on the highly venomous Portuguese manof-war. Despite the allure of these carefully crafted watercolors, you may still be unprepared for the impact of the actual glass masterpieces. To see a glass-spun jellyfish, like the Portuguese man-ofwar, the prey of the sea dragon, even more vibrant in its colors and real in its form than what you could observe in nature—that is the secret of why these pieces have been cherished as art since the day they were made. To paraphrase the great Senegalese environmentalist Baba Dioum, we are moved to conserve what we understand and love. My vision is that these masterpieces of glass art motivate wonder and appreciation for our ocean world. The conservation of our Blaschka glass collection is a perfect analogy for the conservation of our fragile, living marine biodiversity. Everyone knows that glass is easily broken. For the first twenty years of curating our collection, I was unwilling to touch a single piece, so aware was I of its age and fragility. But I have watched our glass conservator, Elizabeth Brill, patiently put hundreds of them back together. Now I move them around without fear. The glass piece that taught me the enduring lesson about our living biodiversity was that first
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favorite, the octopus, now shown on the cover of this book. It was so sad and grim, dusty, faded, and broken when I saw it twentyseven years ago. Now it is restored, its tan and brown spots vibrant, its smooth, sinuous tentacles coiled, as if in wait for a crab upon which to pounce. Our glass octopus is at the same time fragile but resilient and proved capable of repair, despite the years of neglect. Likewise, every marine habitat, filled with spectacular biodiversity, is both fragile and surprisingly resilient. As with a complex piece of art like a glass octopus, a coral reef has many fragile pieces that fit together to create a whole ecosystem. Unfortunately, throughout my career, I’ve watched the pieces be lost. On many coral reefs, for example, we have lost the fish that chomp back the algae that encroaches over the corals, or the ones that eat the snails and sea star that strip the coral’s skin. These worker bees are needed to dust off and clean the reef. We have also lost many integral upstream grass beds, which are like the lungs and kidneys of a bigger ecosystem, eliminating toxins before they reach the reef. Worse, I have watched climate warming kill over twothirds of the species on a reef in a single week. Vastly worse, I have seen dynamite fishing level our most biodiverse of marine ecosystems, the reefs of the Coral Triangle near Indonesia. There are perhaps 3,000 species on these healthy reefs; how is it possible that in a single night, a single fisherman can shatter an entire ecosystem to bits? This is worse than if you collected all 569 of our glass Blaschka animals and smashed them to the ground. A devastating thought to me, because we cherish each one and have invested so much care to conserve and protect them. But if damaged, we would restore them again. This is what we are now doing with marine habitats around the planet. Keep safe and resilient the healthy ones, and pick up and restore some function to the broken ones. We can never give up hope, even for the shattered places.
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The educational value of the Blaschkas’ work has ebbed with time. This is why our collection lived dusty and unused for over a century. The collection was vital in its day, when the first president of Cornell ordered it for our students. Especially at an inland university, students could not easily travel to the coast, and the age of diving with Jacques Cousteau had not yet arrived. This was students’ only chance to appreciate the many branches (and even twigs) on this tree of life. By the mid-twentieth century, biological collecting houses like Ward’s and Carolina, as well as more specialized companies, were doing a big business in collecting and shipping live animals to universities. Who needed glass pieces when they could see the living creatures? Now, once again, we do need the Blaschka collection, both as a time capsule and as inspiration, because even with our ridiculous carbon-burning global mobility and sophisticated diving and photographic gear, many of these animals can’t be seen easily; the diversity in our oceans has declined and many of them are now rare.
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In 2011 I gave a Science Cabaret talk to a packed crowd at the Lost Dog Café in Ithaca, New York. This was my first attempt to tell the story of Cornell’s Blaschka glass animal collection and to address questions about whether I could ever find the living biodiversity that inspired it. I was surprised at the large audience and the fascination with a story I had long lived with. It would be several more years before I fully understood the key to how I held their interest: that art has enormous power to translate nature and shape our fascination in the natural world. James Prosek, a talented environmental artist, explained it to me: “To really relate emotionally to nature, many people need nature to be interpreted
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for them, through art or some experience of the juxtaposition of humans with art.” I realized that this is what our glass masterpieces do for many people who are unfamiliar with jellyfish, octopuses, or sea slugs. After my talk, in the crowd clustered around the aquarium of live sea animals that my students had brought along, I saw David Brown, a videographer, waiting and smiling as I chatted with others. David, with his boundless energy and engaging smile, dressed in the usual rumpled sport coat and jeans of the Ithaca native, looked the part of a rugged adventurer who had filmed narwhals in the Arctic and fin whales in Indonesia as a member of the Cousteau Society team. I was pleased he had shown up and intrigued when he looked me in the eye and said, “I’m hooked on your story of the glass collection and marine biodiversity as a fragile legacy. Your video clips of the live animals reflect amazingly back on the glass masterpieces. It really is a time capsule of the oceans before the industrial age; we could make an entire film about it.” That chance meeting in a bar led to some rather crazy initial dives to find animals like octopus and cuttlefish that I never thought I’d see in the wild, and set me on a different course. David and I then embarked on a series of shared underwater adventures that were by turns difficult, inspiring, and heartbreaking. We have searched and found many Blaschka lookalikes in the freezing waters of the North Atlantic, the North Pacific, and the Mediterranean, and in the warmer reefs of Hawaii and Indonesia. David’s vast experience in technical diving and underwater videography, coupled with his insatiable curiosity and enthusiasm for diving and ocean biodiversity, created the opportunity to bring the animals in our collection to life. On my own, as a research diver, I prefer the safer, well-lit waters of daytime reefs and would never have launched into nighttime black-water dives in the middle of
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the Pacific, or plunged across remote Indonesian reefs chasing octopuses, squid, and sea slugs in the dark.
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My growing passion for the quest to find the living matches to the Blaschka creatures, and my wonder at our experiences—sometimes hopeful, sometimes dispiriting—inspired me to write this book. The moment I came eye to eye with that octopus in Hawaii, I fell in love with this curious, surprisingly smart creature and felt the epic struggle it encounters in today’s oceans. In chapter 6 I talk more about encounters with its relatives, the squid and cuttlefish, and finish my story about why it’s so challenging to hold an eightarmed Houdini. The outcome was that I wanted to spend more time in the octopus’s garden and have others experience how it feels when art comes to life. A Sea of Glass uses the Blaschka collection as a time capsule to focus on animals that were abundant 150 years ago. Each chapter shows the linkages between the animals that dominate our tree of life and the threats they face in our changing oceans. I’ve added an appendix with more scientific detail about invertebrate diversity within each taxon and newly discovered relationships among the groups. There I show the full range of the tree of life that the Blaschkas included in their masterpieces. The main chapters include anemones and corals; jellyfish; soft-bodied worms; sea slugs; octopuses, squid, and cuttlefish; and sea stars and sea cucumbers. The Blaschkas were very deliberate in their efforts to show not all invertebrates, but rather the soft-bodied ones that would not preserve well and that students and the public might never see in life. You won’t find sea urchins, shrimp, crabs, or even many sea stars in the Blaschka collection. Woven throughout are my experiences
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and research on how these animals survive in the ocean. Sharing our adventures to find them amidst the ecological threats they face is an essential part of bringing others along on this project: see what dives put us in danger, where we found beautiful surprises, and where we blundered upon brutal disappointment. And see what we know of the status of these creatures and the threats to their conservation. The final chapter of the book considers how the Blaschka tree of life will likely fare in a rapidly changing ocean.
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A Sea of Glass aims to reawaken the passion of the nineteenth century for natural history and ocean exploration. As it turned out, our quest to find all the animals proved impossible; even the experts studying each group have not seen all the species that the Blaschkas depict. In our quest to find each animal or its closest lookalike, we had to start at the beginning, with names. Fully a third of the names of the original Blaschka species have changed in 150 years, and some that were once considered a single species based on their appearance are now recognized as being several species based on their genetic code. The species depicted by the Blaschkas come from all over the globe and from habitats as varied as tide pools in Wales and the Mediterranean and regions deep in the oceans, like the mid-Atlantic. My lifetime as a biologist studying marine invertebrate biodiversity and climate change impacts in the oceans makes clear to me the urgency of this project, an urgency that stems from the accelerating change in our world’s oceans. Marine biodiversity is caught up in the relentless changes that modernization, over-fishing, warming waters, and ocean acidification are bringing to our shores. Every dive is a new experience combining risk and discovery. It is never clear at the start what I will find:
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unexpected down-sweeping ocean currents or a rare sea slug running along some deep rock wall; large predators that could eat me or bioluminescent squid glowing in a dark ocean. Discovering just how the different species beloved by the Blaschkas cope with both setback and opportunity in their homes, from tide pools to reefs to blue water, is a journey full of surprises. Join me in the voyage to discover who the winners are in our climate lottery, and who is the most fragile and threatened in today’s seas.
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2. ANEMONES AND CORALS Rooted Lives of At-Risk Animals
ON ANY GIVEN DAY in the San Juan Islands, I can pick my way
across the rocky shoreline and see half a dozen different species of anemone. Although a professor at Cornell University, I am fortunate enough to spend my summers teaching at the University of Washington’s Friday Harbor Labs. The San Juan Islands, north of Seattle, are located in the middle of the Salish Sea, an ocean waterway stretching from Puget Sound and the Strait of Juan de Fuca north to the Strait of Georgia, with an unusual bounty of marine diversity. Though simple in their design, anemones come in a surprising variety of shapes, sizes, and colors. Our tide pools are carpeted with the olive green, pink-tipped elegant anemone (Anthopleura elegantissima), as common as a robin in a tree and a close match to the Blaschkas’ Anthopleura ballii. Their color comes from the combination of two solar cells (one tiny brown dinoflagellate or one bright green alga) that live within the anemone and fix carbon from the sun, much like plants do, converting it to energy. But unlike the corals, which have evolved a tight, necessary dependence on their solar cells, these anemones can opt to go without, appearing ghostly white, often in deep shady tide pools
Sea pansy (Renilla muelleri) in glass. The sea pansy is a collection of polyps; a single two-inch-long polyp makes up the base, which anchors it in the sand. The petals of the pansy are formed by large anemone-like feeding polyps. When touched, intense waves of light spread from polyp to polyp, organized by the pansy’s diffuse nerve net. The bioluminescence is caused by a chemical called green fluorescent protein (GFP). Photo by Gary Hodges.
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or beneath overhangs (below). But in between the earthy green and the white anemones exists a whole spectrum of color, shape, and form. I can easily get lost admiring their diversity, as it appears British artist Philip Henry Gosse did in his watercolors of the 1840s (Gosse 1860). elegant anemones (Anthopleura elegantissima) in a san Juan Island tide pool. The pale anemones contain no symbiotic algae. Photo by drew Harvell.
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Gosse’s peeking–into–tide pool lithographs of the British Isle anemones (page 22) inspired much of the Blaschkas’ fascination with these delicate creatures. An English naturalist, Gosse was credited with being the inventor of the aquarium after he created and stocked the first seawater exhibit at the London zoo. He was a passionate naturalist, prolific writer and illustrator, and an expert in ornithology, herpetology, and anemones. His Actinologia Britannica is a stunningly illustrated taxonomy of British sea anemones. It’s clear from Leopold Blaschka’s early watercolors, which are almost identical in style and substance to Gosse’s lithographs, that the glassmaker was influenced by the artist’s passion for anemones. Employing his uncanny ability to create subtle shades of color in glass—pinks, teals, roses, and oranges—Blaschka replicated the beauty not only of Gosse’s lithographs but also of their living equals. The Blaschkas didn’t stop there; they juxtaposed these soft colors with finely spun details like eyespots, tentacles, and tubercles— often in contrasting colors—making the glass models even more appealing. Take, for example, the snakelocks anemone (Anemonia viridis), with its many extra-long aqua tentacles grading into fuchsia tips, or the beadlet anemone (Actinia equina), a rosecolored column set with blue-green eyespots (page 23). Both species are common in shallow coastal waters today, the snakelocks in the Mediterranean and the beadlet in Wales. During their career, the Blaschkas created eighty-five glass models of sea anemones. In addition to being masters of color, they had a knack for re-creating the contours and textures of the body columns, like the lines of studs marching from tentacle to base on species like the Anthopleura ballii. And the glass triplet of the swimming anemone (Stomphia coccinea), with their peachstriped columns grading to bright-tipped tentacles, is evocative
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Lithographs of anemones in a tide pool, by Philip Henry Gosse. From Actinologia Britannica: A History of the British Sea-Anemones and Corals, 1860; courtesy of the Albert R. Mann Library, Cornell University.
Three anemones in glass (from top): snakelocks anemone (Anemonia viridis), beadlet anemone (Actinia equina), and Parantheopsis cruentata. The beadlet and snakelocks anemones are still common on European shores. Photos by Kent Loeffler.
of the exact Blaschka match housed in aquaria and living on the walls of cliffs at the Friday Harbor Labs (below). Anemones are not only the first invertebrates that the Blaschkas molded in glass at the request of Heinrich Reichenbach, director of the Dresden Natural History Museum, they are also the first form of the entire cnidarian group, evolving in Precambrian oceans over 630 million years ago—long before even fish evolved. Although distinct in color and shape, all anemones evolved as variations on the same theme, one that is the most basic and primitive in the ocean: all have a short, wide base column that houses a stomach and ovaries, along with a ring of tentacles that surround a single opening where food goes in and waste comes out. Although their static lifestyle might suggest they’re easy prey, anemones are well defended; many can move by inching across the rocks,
The swimming anemone (Stomphia coccinea) alive in the San Juan Islands (left) and in glass. This anemone swims when threatened by predatory sea stars. Photos by Drew Harvell (left) and Claire Smith.
and of course Stomphia coccinea can even swim. Anemones are largely sit-and-wait predators, quietly reposing in the bottom of a rockweed- or eelgrass-shaded tide pool until a mussel or small crab blunders into their sticky, spring-loaded tentacles. Then zap!, hundreds of threadlike barbs called nematocysts fire, snagging and stunning their prey. Perhaps in the touch tank of a public aquarium, any person can safely experience the pull of an anemone’s nematocysts; the tentacle feels sticky and adheres to the skin but doesn’t break it. So how is this soft-bodied anemone related to calcified corals? It’s all about reproduction and renewable energy. They share the same polyp-form body, and when it comes to reproducing, each elegant anemone can single-handedly make his or her own family by simply splitting in half and then in half again. These kin are all genetically identical clones to the founding anemone and can continue splitting until a single sea anemone has parted into hundreds of versions of itself in one tide pool. Perhaps this has occurred for hundreds of years, with entire sections of coastline originating from one ancestral great-grandmother anemone, who may still be there. It should be no surprise that our great-grandmother anemone is a warrior, with weapons that can be used in territorial wars with other families. Some tide pools have two genetic stocks of anemone; when they find each other they can fight to the death. Teeth and claws are replaced by an armature of stinging capsules, each neatly packed with a coiled harpoon and poison that kills nerves, firing when the trigger is pulled by chemical or mechanical signals. This harpoon may be nature’s fastest cellular mechanism, firing with the speed of a bullet; it shoots in a billionth of a second, with an acceleration of over a million g’s, and injects a lethal neurotoxin upon contact. So in spite of being sedentary, our great-grandmother anemone has the firepower and the
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chemical sensors to capture fast-moving prey and defend the family tide pool. With corals, the same dependable reproductive strategy transforms a single new baby coral into a massive cathedral housing millions of polyps. Though it might seem surprising to some, a coral reef is not a rocky ridge of inorganic substrate that’s been pushed up from the ocean floor by ancient volcanic action; it’s in fact a living colony of coral animals, formed by thousands of polyps budded from an initial parent polyp. The colony operates under one integrated nervous system that coordinates nutrient sharing and defensive behaviors. If you poke a polyp on one side of a coral colony, the tentacles on the other side will retract as a nervous impulse travels across the connected polyps. The essence of a coral or a hydroid colony is to be colonial, with each mouth connected to the next via subterranean channels. As with anemones, each monumental coral colony starts with a single swimming coral larva no larger than a sesame seed, which is tasked with the big job of picking the spot in which to settle and metamorphose into its adult polyp form. Then the magic of construction begins, with the unceasing budding of new polyps, seen beautifully in the Blaschka watercolor of soft corals, including sea pens, encrusting soft corals, and sea pansies (page 27). Now imagine that each polyp in either a sea pansy or hard coral can catch its own small baby crabs, digest them, and share the remains with the others in the colony through stomach linkages that network through the tissue. In the reef-building hard corals, each polyp secretes a complex calcareous skeleton that acts like a hall of mirrors. Like some of their anemone cousins, these polyps are solar-powered animals housing tiny marine algae in their tissues that transform sunlight into energy to build more polyps and
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skeleton. Millions of years of evolution have optimized all aspects of their biology, including the shape of their skeletons and the size of their tentacles, to use solar power. This symbiosis is at once the great miracle that allows vast reefs to form and the Achilles heel that makes them vulnerable to climate change. While the Blaschkas focused primarily on bringing anemones and soft corals to life through glass, some of their watercolors and
sea pens and sea pansies (Renilla muelleri) in a Blaschka watercolor. Courtesy of the rakow research library, Corning museum of Glass, BIB Id: 121319.
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a few models are breathtaking in their detail of reef-building corals, which so many of the Blaschka invertebrates depend on for food, habitat, and reproduction. These great cathedrals of calcium carbonate create habitats that allow coral reefs to be the richest marine ecosystems on earth. Studying the ecology, health, and status of these reef systems is my primary job, and one of my life’s quests is to understand how this most ancient of all immune systems functions in a changing climate. Scientists may disagree about many things, but there is consensus among coral reef scientists that reefs are highly endangered by the double whammy of warming sea temperatures and ocean acidification. We talk about climate change in terms like “business as usual,” meaning we project how much carbon dioxide will accumulate and contribute to increases in greenhouse gas warming if we do not cut our carbon emissions. In 2007, we predicted that under a business-as-usual scenario, most coral reefs would be functionally gone in fifty years (Hoegh-Guldberg et al. 2007). In 2057, I’ll be gone and my students will be as old as I am today, and tropical oceans will have warmed to the point where the symbiosis between most corals and their algal partners will break down. This is not argued: we have already witnessed the demise of many reefs due to “bleaching,” or the breakdown in this symbiosis from ocean warming. In 2013, I was part of a research team that contributed a chapter to the U.S. Climate Change Assessment for Oceans report showing evidence that the demise of coral reefs is one of the largest climate change impacts expected in the ocean (Doney et al. 2013). This transition of an entire ecosystem at risk is already under way. Saying “ecosystem at risk” is an understatement: more than one-third of the foundation species that build reefs are in immediate danger of extinction, twenty coral species were added to the endangered species list in 2014, and entire reef systems can
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die with a single warm event, as happened to some large tracts of reef in Palau and the Indian Ocean during the 1997–98 El Niño event (Burke et al. 2011). Also, by 2057 the average level of carbon dioxide in the tropical oceans may exceed 550 parts per million; that makes the oceans more acidic and is past the threshold at which most corals can build their carbonate skeletons. When the living corals that make up the reef die, then the anemones, sea stars, worms, fish, and turtles that depend on the reef for their home and food will also disappear.
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Long before there was any discussion about greenhouse gas– driven climate change impacts, I encountered the first evidence of their devastating influence on coral reefs. It was 1982, and I was a twenty-six-year-old PhD student from the University of Washington on a fellowship to study the fish and snails that were eating coral on the very low-diversity coral reefs of western Panama. We had steamed for thirty-six hours in the RV Benjamin, an old wooden coastal steamer with an all-Panamanian crew. We chugged out of Panama City, headed to the Uva Island Reefs in the Gulf of Chiriqui, a pristine, secluded place about eighty miles southeast of Corcovado. It was our first day in this remote, uninhabited region of densejungled shores. We were headed to the fish-filled coral reefs that framed the island. As we buckled gear onto our dive tanks and loaded our small Zodiac, we talked about how many large bull sharks would see us and whether we would also be able to see them in these low-visibility waters. I knew the dangers: these waters were packed with bull sharks, which are considered one of the most dangerous sharks in the world, since they like very shallow
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coastal water and are very aggressive, prone to mistaking people for food in low-visibility waters. Peter Glynn, a staff scientist at the Smithsonian Tropical Research Institute, was the world’s leading coral reef biologist at the time, and I felt privileged to be diving his reefs with him. But he was also making me nervous with his talk about all the sharks we would see. As it turned out, the bull sharks were ever present, continually spooking us as they loomed out of the murk. It was a still, early morning and the glass-surfaced ocean reflected the quiet green jungle as we headed to one of Peter’s longterm monitoring plots and my first dive in Chiriqui. I was not a very experienced diver at the time and I don’t mind saying my mind was split between the excitement of being there and my anxiety about big sharks. Once underwater, I forgot my fears and was surprised and confused—all the coral as far as I could see was white. I knew that living coral comes in all colors and shades of tan, brown, green, purple, and even magenta, but never white. I looked more closely and could see the coral’s delicate surface skin, with its living polyps covering the coral, so it was certainly a living reef, but it was eerie and ghostly and not right. To my eye, even the bright fish underwater appeared dazed and confused. These are very shallow reefs, and we were only in about fifteen feet of water, so we gestured to Peter and surfaced. “Why is the coral white, is it safe for us to be in the water?” we asked. He looked pretty shaken and said he’d never seen this before and didn’t know. I still remember the pulse of pure excitement that shot through me. Here I was, a brand new coral reef researcher, with the most respected, experienced coral reef scientist of our time, and he didn’t know why his reef was devoid of all pigments? At the time, none of us were aware of the import of our discovery. My excitement would have been tempered had I known that this was only the beginning of a
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horrific series of catastrophic coral bleaching and mortality events that by my mid-career would threaten the very sustainability of an entire ecosystem worldwide. As we dove back down, we started to see more shades of pale— some corals were white, while other less common coral species, like Gardinoseris and Pavona, still retained their brown pigment. These reefs are like big canyons, and as we went deeper and rounded an outcropping, we saw a flash of movement. Chilled, I realized we had an escort of several bull sharks, larger than I, looming in and out of the limits of our vision. The combination of the ghostly conditions, murky water, and shark escort was enough to drive us out of the water. After a long day in the water, we gathered on the deck of the Benjamin over beer and dinner. Peter mulled over the possible causes of what he accurately reported was a coral stress response. Perhaps it was an unusual spike in warm or cold temperature, or perhaps low salinity had caused the symbiosis between coral and algae to break down. He was visibly excited to see a response on this scale and had worked hard all day on underwater surveys of his permanent transects to record the extent and different responses among the species—some of the coral had already died, while other species appeared unaffected. The papers Peter Glynn published about this event were the first scientific recordings of a coral bleaching that ultimately killed large tracts of reefs in Costa Rica, Panama, Colombia, and the Galapagos Islands (Glynn 1983, 1984). At the time, Peter estimated that this was the result of the most severe warming event in at least 190 years. Since then, this record has been smashed by the ever-quickening pace of deadly bleaching events from the Florida Keys to Mexico to Australia, Fiji, and Palau. Although there was also a large Caribbean coral bleaching event in 1988, the next event I experienced was in 1997, in the Florida
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Keys. As an established associate professor at Cornell, I was prepared this time and understood what was happening when the scleractinian corals in the Florida Keys turned white. My postdoctoral fellow at the time, Kiho Kim, and I were working with Craig Quirolo of Reef Relief to record the impacts that a disease caused by the land-based fungus Aspergillus was having on vast stands of purple sea fans, a soft coral that was melting away Caribbeanwide (Kim and Harvell 1994). Kiho is now a gray-haired professor and chair of his department at American University, but at the time he was a newly minted PhD doing a postdoctoral residency in my lab. Together we launched a project that would be the focus of the next twenty years of my lab’s work: how climate and coastal stress were triggering new outbreaks of infectious disease on coral reefs. As an octocoral, soft-bodied and with eight tentacles, sea fans are closely related to some of the Blaschka models. One hypothesis for why these octocorals were sick with a land-based fungus was that warming was causing corals to be stressed, thus compromising their immunity and making them more susceptible to opportunistic diseases like the one the Aspergillus fungus was causing. Aspergillus can also be a human pathogen, and so there were many big questions we were trying to answer about emergent diseases in the ocean and their links with land. But our work with the sea fans was interrupted when we observed the reef turning white in Florida and another species of soft coral, Briareum asbestinum, not only turning white but suffering decaying tissue and dying in high numbers. The paper we published from that event demonstrated that some of the deaths we were attributing to bleaching and heat stress were actually caused by infectious disease (Harvell et al. 2001). As the winter of 1997–98 unfolded, we experienced the largest El Niño event in hundreds of years, and its impact stretched around the globe. This event elevated to 75
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percent the proportion of the world’s coral reefs that were considered threatened. Corals died in bleaching events that included the Caribbean, the Indian Ocean, the Great Barrier Reef, and vast tracts of the Pacific (Burke et al. 2011). In 2004, we worked on the reefs of Palau, some of the most biodiverse in the world, and observed vast stretches, tens of kilometers in length, of completely dead reef that had still not recovered from the mass mortality of 1998. In chapter 8, I discuss the heat-related mass mortalities that are plaguing the Mediterranean and putting our Blaschka match, the orange cup coral, on the endangered species list (page 34). In 2004, I received a call from Andy Hooten and Marea Hatziolos of the World Bank asking me to join a global project to improve the sustainability of coral reefs. The World Bank was worried about its investments: the economies of many developing countries are critically dependent on coral reef fisheries and other coral reef ecosystem services. Then, just as we were struggling to understand the consequences of severe warming impacts on coral reefs, the second bomb dropped at the annual meeting of our coral sustainability team in Mexico in 2006. In addition to warming caused by the accumulation of carbon dioxide in the atmosphere, the oceans were becoming detectably more acidic from the direct accumulation of carbon dioxide. The projections all showed clearly that this was going to be catastrophic. Nine years later, the beginnings of this ocean catastrophe can already be seen in the waters of the Pacific Northwest (see chapters 6 and 8). While there is agreement that coral reefs worldwide are highly endangered by climate warming and ocean acidification, there is much speculation about the details of what will happen. For example, some ask whether coral species will escape the threat of heat stress by moving to cooler waters (Precht and Aronson 2004). Certainly this is what we have witnessed in the fossil record as a
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response to climate change. Others argue that adaptation and evolutionary change will slow the pace of this catastrophe (Palumbi et al. 2014). But this increase in carbon dioxide–driven warming and acidity is vastly more rapid than ever experienced. If the amount of carbon dioxide in the atmosphere is not curbed, within fifty years the oceans will become so corrosive that most species will not be
Orange cup coral (Astroides calycularis) in glass. This nocturnal coral does not have photosynthetic algae. It is currently listed as endangered in the Mediterranean, but we saw some on a dive at Portofino, Italy. Photo by Elizabeth R. Brill.
able to calcify. We know this because in laboratory experiments, coral colonies grown in corrosive, low-pH conditions actually survive, but they dissociate from a calcified colony into a non-calcified collection of anemones, in what seems like a bizarre parody of the evolutionary process that produced corals from the more ancient anemones in the first place. A few tough, starling-like species that can tolerate both heat stress and acidic waters will persist, as we have observed in natural carbon dioxide seeps near Papua New Guinea. This is not a coral reef and will not house the tremendous biodiversity and fishery riches that a healthy reef supports (Sale 2012). So how do the Blaschkas and their fragile glass models figure here? Because so many of their living counterparts depend on coral reefs for habitat, my trips around the world to document their well-being naturally include forays into fragile reef territory. Coral reefs are the backdrop to the kaleidoscope of colorful and unique creatures I have set out to find, including the anemones. It’s ironic that of all the invertebrates on my list, anemones are the closest relatives to the corals and yet we know very little about them in terms of extinction risk.
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After years of cataloguing ecological disaster on the biodiverse reefs of the tropics, it was a relief to venture into old, familiar waters near my home in the San Juan Islands; these marine ecosystems haven’t experienced some of the ravages of climate change and are still vibrant and healthy. On this dive, David and I were looking for the living counterpart of one of the Blaschkas’ more stunning glass models. Leopold’s models of the plumose (Metridium senile) anemones, shown in the Dublin Natural History Museum
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packed tentacle by mouth into a single bank of white and beige, are just like the living anemones on deep rock walls in the San Juan Islands. They are of particular interest to us because Leopold Blaschka made a special request to have a live collection sent from Kiel, Germany, in 1880, which he planned to keep in his aquarium. As with so many of our Blaschka invertebrates, the species name has changed. Leopold asks for Actinoloba dianthus, which is now named Metridium senile. He also reveals in his letter the method of successful shipping: animals were packed moist, but without seawater, in marine algae and sent through the mail. An excerpt of his request to a Mr. Handtke in Kiel, circa July 1880, follows. It includes mention of the Christmas anemone, Tealia crassicornis, now named Urticina crassicornis and also abundant in Friday Harbor. Then I request you, to send me when it is possible for you an amount of fresh plumose anemones (Actinoloba dianthus). These may be big or small, of various colour, whatever it is possible, and I prefer it the most, when they still find themselves on the very same substrates as where they were found on. I would love it, if you would try to send me by mail a number of Actinoloba, dry, I mean with no water, only wrapped in moist algae and packed in a can or in a keg. If possible, please add a few of Tealia crassicornis as well. (Reiling 2007)
Our very first dive to seek out Blaschka lookalikes was a daytime dive to see if we could still find these deep banks of the plumose anemone in the dark, cold waters of the Pacific Northwest. Given that it’s in my own backyard, it was a natural first start. In addition, these are some of the richest waters off the continental United States, with a high number of the kinds of soft-bodied animals that the Blaschkas created: anemones, nudibranchs, worms,
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and sea cucumbers. The only issue was that I’m no longer so fond of diving in rugged, icy seas, and it requires a lot of stiff, heavy gear. In fact, I hadn’t done a cold-water dive in decades. In making the transition to working in the warm, clear waters of the tropics, I had left behind my graduate school plunges into these dark, current-driven waters. It had been almost thirty years since I’d last visited this area. The tantalizing allure of seeing the anemoneencrusted rock walls again—and reassuring myself that they were still thriving—convinced me it was worth doing. As David and I arrived at the site called Shady Cove, little more than a notch in the steep, rocky shore, I considered the dark dihedral rock that led sharply down to the enormous underwater cliff that lay fifty feet below the surface. The hope was that the overhang would hold back some of the lush kelp growth and permit us to find the giant plumose anemone (Metridium farcimen, formerly M. senile). Although it covers the undersides of many docks and pilings, we wanted to find it in a more natural habitat, framing the rich biodiversity of our deep underwater cliffs. As we suited up, I eyed the dark water swirling around us. The Pacific Northwest has some of the more dangerous diving conditions to be found anywhere, including very cold water and currents so strong we could only safely dive on the exact slack of the tide, which is the one thirty-to-sixty-minute point during each day when the tide is neither rising or falling. Unfortunately for us, because it was a full moon, the slack tide was short and would change fast, on top of which Shady Cove is known for fast and unpredictable tide changes. In long-ago dives here, we had surfaced to currents so strong it felt like being in a river. As I contemplated the moving water, our boat captain reminded us that we’d only have about thirty minutes before the tide turned, so it was now or never.
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My unwillingness to get in the water was tempered by the certainty that a high current would make it harder to stay in one site and find our anemones and nudibranchs. I grabbed my flashlight and decided to leave the camera behind, grinned at David, my co-conspirator in this endeavor, and went over the side. My wetsuit was thick, tight, and stiff, but it did a good job of slowing the icy trickle of cold water into the suit. It was hard to swim on the surface, weighed down by all the rubber and gear, so I signaled to David that I was going down. As I slowly sank away from the lighted surface, I swam toward the wall. With surprise and a growing uneasiness, I realized that the cold was not nearly as much a problem as the dark. It was the height of the summer plankton bloom and the light was so quickly attenuated that within twenty feet it was completely, disorientingly dark. I couldn’t see David, I couldn’t see the bottom, I couldn’t see the wall, and I could barely see the surface. I was breathing too fast, and my suit was too tight and confining. My panic grew at a rate almost too fast to control. I grabbed for my rented gauge and realized the tiny numbers were too small for me to read easily, so I didn’t even know my depth, and the borrowed light was tricky to turn on. I worked to calm myself: Slow your breathing, find the wall, adjust your buoyancy and breathe . . . move slowly, look at something under the kelp. It worked; I didn’t bolt for the surface. I looked at David, and out of habit only I gave him a grin and a thumbs-up, but it was enough to refocus and follow my training, adjust my buoyancy, take a slow breath, and proceed down. In thirty years of diving, this was the first time I had almost aborted a dive. I was still not happy, but I was excited to see my old invertebrate friends on the rock wall that had been the site of my very first underwater job. As an undergraduate, I worked for an invertebrate paleontologist who was researching the question of whether mussels had
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contributed to mass extinctions of brachiopods, a non-mollusc bivalve that created vast fossil reefs, by climbing over and smothering them. Shady Cove has a fantastic population of the smiling brachiopod at diving depths, so it was a good site to do experiments. I helped Charlie Thayer, then at the University of Pennsylvania, set up and photograph his experiments at a depth of about fifty feet. I also did some of my graduate work on nudibranchs and their prey in Shady Cove and had traded dives with others, including my husband-to-be, while working these cold waters. Back then, the walls of Shady Cove were cloaked with many-colored carpets of sea squirts and pink anemones, each fighting for space with the next, and canopied by the gorgeous, bright-red feeding tentacles of the armored sea cucumber. The predatory clown nudibranch and fairy-white alabaster nudibranch used to be common, cruising the wall like leopards of the deep, and we hoped to find them today. So it was like coming home to be there again and see those same colorful critters. But suddenly, out of the corner of my eye, I saw it—a big flash of white, like some giant whale or shark—twenty feet deeper. Relief flooded in as I realized the “beast” was only a specter of my imagination. Instead, we had found a band of giant plumose anemones at sixty feet—hovering like a cloud from the wall. A group of twenty huge anemones, each longer than my arm and possibly one hundred years old, stretched their stinging tentacles into the stirring current. They are magical, ghostly beings, riding the currents on their deep, ancient cliffs. For a moment I felt suspended in time as well as space, fighting the pull of the rising current, watching the columns of white bend gently as outstretched tentacles captured newly stirred plankton brushing past the wall (page 40). We moved on, fighting our way upstream, a little deeper. Once again, a ledge of ghostly white floated below,
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A creamy bank of the giant plumose anemone (Metridium farcimen), an abundant anemone in the san Juan Islands. The plush tentacles of these extremely long-lived anemones filter plankton from high currents. Photo by david o. Brown.
and we moved on to an ever-larger bank of anemones, stretched out from under an overhang, crowded at their bright bases with multicolored algae, sea squirts, sea cucumbers, and carnivorous nudibranchs. It was the highlight of my summer to see this familiar, richly biodiverse community unchanged after thirty years. As the current rose, David and I stopped kicking hard to stay in place and instead drifted back along the wall. Glimpses of orange and red, the swimming and Christmas anemones, glimmered along the rocks as we slowly ascended the wall. Illuminated in the beam of light and on film, a garden of brilliant orange sea cucumbers stretched to the edges of their rocks, capturing their piece of
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the current with sticky tentacles. Stopping, we watched as one by one, their outstretched arms were laden with plankton and wiped clean in the mouth. Then, without missing a beat, the cucumbers redeployed their arms against the quickening flow. Then there we were, twenty feet from the surface, in the warm and light, carried fast in the current as we took time out for our three-minute safety stop, allowing most of the residual nitrogen in our blood (the result of breathing compressed air at depth) to bubble out. And the show wasn’t over as we zoomed along—another of our Blaschka lookalikes drifted bright with us, a moon jellyfish, true inhabitant of the fast waters. The yard-long, pure white Metridium from Shady Cove are in contrast to other anemones in the Blaschka collection: a brightly colored diversity of tentacle forms from long, slender, and pinktipped to short, stubby, and balloon- or trident-shaped. Unlike the corals whose demise we are cataloguing carefully, much less is known about how individual anemone species slip out of even our common marine habitats. But here, beneath the familiar cold waters of my life’s work, I am moved by the elegant simplicity of this thriving white animal. It reminds me that life persists, despite the losses we catalogue every day. I let the tide carry me back to the boat, secure in my place in it all. I am ready to do it again.
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3. JELLYFISH The Rise of the Medusa
TO FIND THE WILY, often transparent jellyfish, it helps to go to
the open ocean at night, which is why David Brown, Catherine Kim, and I were headed a mile out to sea from the Big Island of Hawaii. Catherine is one of our intrepid Cornell post-graduates, so entranced with diving and the diversity of invertebrate form and function that she refused to be left behind and came along as second camera. The trade winds were up a bit and the Pacific Ocean stretched very big in the offshore sunset as we motored to deep water a mile offshore. As we left the coastline behind, the Big Island seemed very small in the darkening ocean. Of the vast groups of animals organized under the phylum Cnidaria, which includes anemones and corals, the jellyfish—or medusae—are the only mobile arm of the clan. With their long flowing tentacles, the medusae harken back to their namesake, the mythical Medusa, who had writhing snakes for hair and the ability to turn people into stone. These may be the most spectacular of the Blaschka works. They capture in detail the different forms, shapes, and colors of the free-floating medusae: the look of each delicate bell and trailing tentacle, and the different forms of jellies. This group stretches from the relatively simple but sometimes cheetahsized oceangoing scyphozoans (page 45) with their blue, orange, Portuguese man-of-war (Physalia physalis) in glass. The man-of-war has been called a superorganism because it is a complicated colony of feeding, defensive, and reproductive polyps all working together. It is venomous and common in today’s oceans. Photo by Gary Hodges.
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Blaschka watercolors showing a diverse selection of jellyfish including Physalia. Courtesy of the Rakow Research library, Corning Museum of Glass, BiB iD: 121782, 121785.
or transparent bells, long trailing mouth palps, and almost infinite tentacles, to the rather austere hydrozoans, with their high, transparent bells, and the stunningly complex, colonial forms of the giant siphonophores, which include the dread Portuguese manof-war. The siphonophores have been called superorganisms because each jelly is actually an individual comprised of polyps and medusae with different functions, all integrated by evolution into one body. I am amazed at the Blaschkas’ mastery in creating a glass siphonophore. Take, for example, Apolemia, a creature that in nature stretches to over thirty feet and is composed of a swimming bell and four different polyp types—each specialized for defense, feeding, swimming, or reproducing. The defense polyps
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lion’s mane jellyfish (Cyanea capillata) in a Blaschka watercolor (left) and glass. The lion’s mane is the world’s largest jellyfish, exceeding three feet in diameter, and is frequently seen in the san Juan islands. Watercolor courtesy of the Rakow Research library, Corning Museum of Glass, BiB iD: 122348; photo by Gary hodges.
have batteries of stinging cells, the feeding polyps have a stomach, and the reproductive polyps have eggs or sperm. Apolemia looms as the largest of our models, at over a foot of transparent glass bell and trailing tentacles (page 47). I can imagine what it is like to see this in the ocean, swimming calmly through the dark waters of the night plankton, likely lit with its own bioluminescent glow. But there is another, darker side to this group called the jellyfish. Although they don’t literally turn people to stone, these fierce carnivores are capable of taking down a person via their springloaded, fast-action harpoons loaded with neurotoxins. Some species can kill a person in two minutes. The Irukandji jelly is deeply feared by Indo-Pacific divers because this tiny, almost invisible
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creature can deliver a sting that induces severe, even lethal symptoms, including blinding headache, backache, muscle pains, chest and abdominal pain, vomiting, sweating, tachycardia, and pulmonary edema. Death by Irukandji comes in small packages, as these jellyfish are very small cubomedusans, or box jellies, with a squarish bell about half an inch wide and four tentacles that range in length from just a few inches to up to two feet. The stingers (nematocysts) are in clumps, appearing as rings of small red dots around the bell and along the tentacles. Now imagine a huge swarm of jellyfish, so large it colors the ocean surface purple and weighs tens to hundreds of tons. The Apolemia siphonophore, in addition to being huge, can travel in swarms so massive as to clog the intakes of power plants. In 2011, Apolemia shut down several stations in Wales (Gershwin 2013). Massive swarms of other jellies have caused similar closures of nuclear plants. For example, in 2013 the largest reactor in the world, in Sweden, was closed by a swarm of moon jellies, Aurelia aurita, also a Blaschka match. During the fall of 2013, swarms of another Blaschka match, Pelagia noctiluca, the mauve stinger, killed tens of thousands of salmon from the Clare Island salmon farm in Ireland, after hospitalizing a swimmer with purple welts from his eyelids to his feet (Ryan 2013). While dangerous jelly blooms affecting swimmers have long been common in the Mediterranean, warming waters may be favoring blooms in the Atlantic and causing more problems for salmon farms and power plants. My favorite story of jellyfish mayhem is when the USS Ronald Reagan, a nuclear-powered aircraft carrier, docked in Brisbane, Australia. Thousands of jellyfish were sucked into the cooling system and forced a shutdown of the ship’s onboard functions. After days of battling the jellies, the carrier was forced to leave port amid headlines like “Mighty Warship Feels the Sting.” Based on these highly publicized incidents, you might think jellyfish are everywhere, but
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Siphonophores in glass: Apolemia uvaria (left) and Rosacea cymbiformis. The Apolemia can stretch to thirty feet in length and occur in high enough densities to kill fish in farms or clog power plants. Photos by Kent Loeffler (left) and Gary Hodges.
in reality, finding these extremely delicate but often dangerous animals is not as easy as poking around in tide pools. Finding the more interesting species in the group requires diving in the open ocean.
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My students and I, ever fascinated by different habitats and invertebrate forms, had often joked that while “the black water dive” in Hawaii was a very exciting opportunity to see unusual bioluminescent plankton, it was too scary to actually do. For those of us used to working on shallow reefs in bright day, it was not appealing to imagine being set like a fishing lure in the middle of the darkened Pacific Ocean, where you’re at risk of encountering great white and tiger sharks during their prime feeding hours. Of the 480 shark species, only great whites, tigers, and bulls are responsible for double-digit attacks on humans, and both great whites and tigers are still common in the waters off Hawaii. Of course the danger to us is vanishingly small; some estimates put the probability of being attacked by a shark at one in a million, but low probability events can loom large in the dark, especially in a year that had seen a record fourteen shark attacks and two deaths in the Hawaiian Islands. On our black water dive, we would be clipped with carabiners to weighted fifty-foot lines from the boat; we would be able to swim up and down the lines but would not be in danger of dropping too deep or getting left behind if a strong wind pushed the boat too fast. Geared up in the dark rocking boat, David, Catherine, and I clipped onto our safety lines, talking about what we hoped to see on this dive. As always, David hoped to see his favorite invertebrate, which is any kind of octopus or squid. A night dive in the
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open ocean is the realm of oceanic squid and planktonic baby octopuses, some no bigger than your thumbnail. Catherine didn’t say, but I knew she was the one hoping to see sharks in the dark. My thoughts were on the bioluminescent siphonophores we might see and my hope there would not be minefields of stinging tentacles. Still talking, we slipped below the surface without lights, into darkness punctuated by bioluminescent splashes. The bioluminescence of jellyfish is also what first inspired Leopold Blaschka to craft sea animals from glass. Although his first models, inspired by the anemone watercolors of Gosse, were of anemones, in 1864 he began experimenting with jellyfish and squid in glass (Reiling 1998). Seeking solace after the death of his wife, he traveled aboard the brig Pauline to North America in 1853. The boat was becalmed on the Atlantic, and this is where Leopold observed several species of jellyfish, including the Portuguese manof-war. His diary entry from this voyage reveals how entranced he was by the forms of the jellyfish and their evening light shows of bioluminescence. This is the moment, on one of those still ocean evenings, when he first sees the live, bioluminescent jellyfish appearing as if spun from glass: We are on a sailing ship in the Atlantic Ocean, immobilised because of the calm; it is a beautiful night in May. Hopefully we look over the darkness of the sea which is as smooth as a mirror: in various places there emerges all around a flash-like bundle of light beams, like thousands of sparks, that form true bundles of fire and of other bright lighting spots, as if they are surrounded by mirrored stars. There emerges close before us a small spot in a sharp-greenish light, which becomes ever larger and larger and finally forms a bright shining sun-like figure. A second one develops, a third; ten, a hundred of these suns light up at a certain distance from the peculiarly sparkling intervals, bright lighting circles form strangely formed figures, with in between places in
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a glowing light, an indescribably beautiful scene originates . . . it is, as if they wanted to lure the enchanted observer into a realm of fairies. (Reiling 1998)
In our open-ocean realm of fairies, those bioluminescent splashes started to come by fast, but we had to drift close to identify whether they were jellyfish, ctenophores, salps, squid, or pelagic snails. Collectively, these pelagic open-ocean animals make up over a hundred of our glass models. As we settled into our depth and turned on lights, we could see a glittering stream of tiny plankton float by us. It was an eerie and unnerving experience to hang in the dark ocean, straining to see what might be coming next, completely unable to see what was below but knowing the bottom stretched hundreds upon hundreds of feet down and was full of big things that might eat us. Would great white sharks or enormous Humboldt squid come shooting from the depths? I nervously double-checked my tether, since it was my only link to the line that allowed me to know up from down. With no lighted surface for orientation, no ability to see my bubbles, and almost weightless, I could not orient myself in space. Then, at the edge of my light, I saw a whiter, glowing shape and pulled to the end of my tether to get a look. A baseball-sized lobate ctenophore, propelled with a changing rainbow of reflective purple, gold, and blue cilia, swam through the beam. These large lobate ctenophores are predators closely resembling the swimming bells of the cnidarian jellyfish. They are also called comb jellies because of the way their sparkling cilia are arranged in orderly rows, like the teeth of a comb. In a bizarre reversal of the normal case where fish eat jellies, these large lobate ctenophores are capable of gobbling small fish from the water column, and in large numbers they can impact the food web. In one instance in the 1980s,
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an invading species of ctenophore, Mnemiopsis leidyi, cleared the Black Sea of fish. Why? Partly because it was a new invader, but also because it entered an over-fished sea that lacked top predators like mackerel and offered nutrient-rich conditions that were optimal for Mnemiopsis. The lobate ctenophores are not a Blaschka match, but as this pulsing, glassy predator moves off, in glides one of its strange cousins, the Venus girdle ctenophore, Cestum veneris. It is otherworldly, a transparent, foot-wide, ribbon-thin wing swimming through the water, hunting for small zooplankton. I can see this thin transparent animal only because of the light of the flickering iridescent ridges of its comb rows as it swims steadily past. This ctenophore is only a foot wide, and the Blaschkas’ work in glass is even smaller, but the Mediterranean one can be over three feet wide. Not only does it look mysterious, but as far as I know, its role in nature is poorly understood. As this unusual Blaschka match swims off, I have time to catch my breath and look around, remembering to wonder about sharks. Happily, none have appeared. I also did not want to blunder into either a Portuguese manof-war siphonophore or an even more venomous cubomedusa, like the Irukandji, in the dark Hawaiian waters. Sure enough, the siphonophores were putting on a breathtaking show. Small, fast, and bioluminescent, they were tiny flashes of jet propulsion. When hunting, they stretch out their long tentacles to five times their contracted lengths of four inches or so. When prey is captured, they haul in their lines. And when danger bumps, giant axons fire a signal to contractile muscles that zip up the tentacles, and the bell powers into high speed; what was a foot-long string of stinging tentacles disappears in a four-inch flash of jet propulsion. Somehow the name “jellyfish” doesn’t quite capture the extravagant evolution and biology at work here.
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It was surreal and sublime to drift motionless in the middle of the Pacific Ocean, fifty feet down, watching a parade of diversity wash past us. We could feel and see the pulse of the ancient food web of the ocean, which seemed unchanged from deep time of 500 million years ago. Like the bioluminescence that first captivated Leopold Blaschka, with our lights off, we could see first a flash and then whole chains of light drifting through the water, emitted by the siphonophores and ctenophores. We continued to enjoy the light show as we slowly ascended our lines to return to the waiting boat and hot tea. But just how “unchanged” are these food webs, let alone the oceans they inhabit? I was determined to find out by going to the habitats that first inspired the Blaschkas.
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The Ligurian coast of Italy should be ground zero for finding the most Blaschka matches, because the Blaschkas had many live animals sent to them from the marine lab Stazione Zoologica Anton Dohrn in Naples. I was on the lookout not only for jellyfish but also for octopuses and small, bright nudibranchs. On my first scoping trip as part of a family vacation, I was able to do two dives on the Ligurian coast. My scientific colleague Dr. Sylvia Cocito from the Centro Ricerche Ambiente Marino di Santa Teresa dell’ENEA in La Spezia had sent me to this rocky outcrop of land called Portofino, right at the top of the Italian boot. She suggested this as the spot with the highest marine biodiversity in the Ligurian Sea. Sylvia reported that many habitats in the Ligurian Sea had been over-fished and were severely depleted, but that Portofino was a rare oasis of biodiversity and might be a refuge for some Blaschka invertebrates. I needed to see for myself how these creatures were faring.
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My target was to dive inside the no-fishing preserve on the rocky headland of Portofino. We had waited over ten days, hiking the trails of the Cinque Terre, for the extremely high winds, rough waves, and rain to pass. It finally dawned bright, the seas flat calm, and my son Nathan and I decided to give it a try. Nathan, a college senior, had trained to dive in the warmer waters of Hawaii and was adept at finding rare fish and invertebrates. We arrived at our first dive site, a shipwreck outside the preserve that was exposed to the full fetch of the Mediterranean, whose waves were crashing high plumes of spray against the sheer rock walls. We were outfitted in unfamiliar cold-water dive gear and accompanied by a divemaster who spoke only Italian, which we did not. Fortunately, many aspects of launching, conducting, and returning from a dive are prescribed by safety rules that are universal, so we understood most of the plan: drop over the side, wait at the surface buoy for the group to assemble, find your buddy, and drop slowly along the safety line to the bottom, sixty feet down. Once safely at depth, where it was nearly dark, interesting animals loomed along the wall beside the submarine-sized, somewhat ominous wreck of the old cargo ship Mohawk Deer, which sank in 1967 as it was returning to port. As we swam cautiously around the hull, uncertain of what might come zooming out of the depths, we admired a brilliant covering of orange tentacles attached to an endemic and endangered cup coral and a Blaschka match, Astroides calycularis (page 34). After rounding the spooky wreck, we moved along a sheer wall and found, tucked into a crevice, a mouse-size tube anemone with long red and black tentacles (Cerianthus membranaceaus). It was similar to our Blaschka tube anemone and was the largest and brightest tube-building anemone I had ever seen. Nathan and I communicated our excitement at what we were seeing through a series of
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squeaks, hmmunhs, and hand signals. We worked our way around the wreck, finding, spotlighting, and photographing a whole series of Blaschka matches: orange Astroides cup coral; golden star coral (Balanophyllia regia); orange sea squirt; several feather worms, including the Mediterranean feather duster; and two colonial ascidians. Always a pro at finding the right critters, Nathan eventually gestured me over to see the living counterpart of one of my favorite Blaschka watercolors, the red-tentacled tube-building worm Serpula vermicularis (page 84). I hovered there, feeling the thread of time between Leopold Blaschka and me spooling back on itself as I watched this small worm feeding in the current, much like its ancestors had when Blaschka first captured them in glass. After we circled the wreck and the wall, the divemaster gestured us toward shallower water and moved off quickly. Before I knew it, we were on an unplanned ascent to shallow water and suddenly entered the realm of the mauve stinger jelly, which I didn’t then realize was dangerous. After I finished admiring the amethyst-studded purple bells and eighteen-inch-trailing mouth palps (page 55), I noticed the almost invisible, translucent tentacles trailing twenty feet beyond the jellyfish. They were set like a minefield stretching from the bell of the jellyfish to the tips of its tentacles. While I didn’t know its reputation as a hazard, it did occur to me that they would be loaded with stinging nematocysts that could deliver a neurotoxin as potent as that of the Portuguese man-of-war. No worry, even though we were in the middle of a swarm of over thirty jellies. The water was cold, about 63°F, and I was buttoned up in neoprene so tight, from thick hood to dry suit, that I was completely impervious to tiny harpoons from even the most toxic jellyfish. What I didn’t know was that similar swarms of this jelly had just cleared the beaches of the Mediterranean from
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Catalonia to La Spezia. Its toxin-loaded tentacles had been responsible for tens of thousands of emergency room visits and even a fatality. It is also one of the more spectacular of the glass models in our Blaschka collection and one that never fails to bring me straight to the feeling of being in the open ocean. While it was awe inspiring to be in the midst of these otherworldly creatures, the sheer size of this jellyfish bloom indicated that the ecological conditions here were out of balance. The mauve stinger is a predatory jellyfish that snags small larval fish with long invisible tentacles, stunning them with harpoons
The mauve stinger (Pelagia noctiluca), a jellyfish with a sting capable of clearing Mediterranean beaches. (from left) a live jellyfish in the Mediterranean, a Blaschka jellyfish in glass, and a Blaschka watercolor. Photos by Drew harvell (left) and the Muséum d’histoire Naturelle, Geneva. Watercolor courtesy of the Rakow Research library, Corning Museum of Glass, BiB iD: 122405.
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of stinging cells, then retracts the meal to its mouth palps. But it isn’t the abundant food that is spurring these jellyfish blooms; instead, it’s what ecologists call the “top-down effect.” Put simply, the predators that once controlled jellyfish populations are missing from much of the Mediterranean, including our first dive site. Not a fish could be seen and certainly not the turtles and sunfish that normally eat the adult mauve stinger. And Pelagia wasn’t the only Blaschka-match jellyfish that was present in bloom conditions during our dives. Some of the beaches had taken on a blue sheen from the rafts of small, cobalt-blue by-the-wind sailors (Velella velella) that had washed ashore (page 57). Although the animal is no bigger than a bar of soap, the blooms were so big that the entire surface of the bay glistened from the reflections of their transparent sail-like fins. Velella is called by-the-wind sailor because it has a stiff, functional, transparent sail that catches the wind and propels the jellyfish through the water. Beneath the sail and the float that keeps it at the surface is the business part of the jelly—a bright blue collection of stinging tentacles that stretch down to ply the waters for baby fish. Look more closely at the mass of bright-blue tentacles and you will find that this is actually a colony with hundreds of polyps, some specialized for feeding, some loaded with stinging cells for defense, and others for reproduction. The reproductive polyps release hundreds of tiny medusae, each of which will sail the sea for three weeks under solar power provided by their symbiotic algae. These halfinch voyagers will mature and release eggs and sperm, which will in turn develop into a new sailor. How incredible is this adaptation of a jellyfish for voyaging the seas? Even better: some forms are right-handed and are driven by the winds in a clockwise gyre, and on others, the sail is set crosswise and travels the opposite route.
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By-the-wind sailor (Velella velella) in glass (left) and washed onto a Mediterranean beach, where it can gather into huge blue-tinted windrows. Photos by Claire smith (left) and Drew harvell.
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While some of the Blaschkas’ fascination with jellyfish originated with Leopold’s first open-ocean experiences and the animals’ glass-like appearance, another influence played prominently in the jellyfish theme. Ernst Haeckel (1834–1919), a professor at Jena University, was both a scientific giant of his time and a highly controversial figure. He described more than 2,000 genus names and more than 3,500 new species of invertebrates (Reiling 1998). Haeckel’s chief scientific interests lay in evolution and life development processes in general, which culminated in his beautifully illustrated Kunstformen der Natur (Art Forms of Nature), a collection of one hundred detailed color illustrations of animals and sea creatures. Haeckel is notorious for his biogenic law, commonly referred to as the “theory of recapitulation.” Haeckel’s recapitulation theory
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posits that the embryonic development of the individual of every species (ontogeny) fully repeats the historical development of the species (phylogeny). In other words, each successive stage in the development of an individual represents one of the adult forms that appeared in its evolutionary history. He posited that a group of related animal forms could be viewed as steps in an evolutionary series, and that by studying a succession of shapes in embryonic development, the laws that define the form of the adult organism could be clarified. For example, Haeckel proposed that the pharyngeal grooves in the neck of a human embryo not only resembled the gill slits of fish, but also signified the trace of a fishlike ancestor. When fossil records were not available, the study of embryonic stages could show scientists what the animal’s ancestors looked like. Although the ideas were appealing and captured important biological insights, some of the details have also been discredited (Gould 2000). We know from the letters that both Leopold and Rudolf wrote to Haeckel that the Blaschkas admired and followed Haeckel’s work closely, and we can see the evidence of it in their work (Reiling 1998). This influence appeared first in some of the Blaschkas’ watercolors of anemones, which copied the exact forms of watercolors by both Haeckel and Philip Henry Gosse. Henri Reiling emphasizes that the admiration was mutual and the passion was shared; Haeckel included a photograph of a Blaschka glass model, Bougainvillia fruticosa, in his book Die Natur als Künstlerin (Nature as an artist, 1913). Dresden, 11 June 1877 Highly esteemed Mr Professor, After I diligently copied and studied all that was necessary from the books by Agassiz and Milne Edwards, that you kindly lent me,
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I return these to you at the same time by mail and again I most kindly thank you for all your obliging complaisance. It enabled me indeed to execute my new catalogue more completely and only limited to scientific models. Again most kindly thanking, greeting, with all respect yours devoted L. Blaschka
Rudolf displays the same respectful, eager charm in his continuing correspondence with Haeckel a few years later (Reiling 2007): Highly esteemed Sir, On receiving your favour I thank you most kindly for your pleasing and clarifying answer. Your announcement that you intend to come to Dresden next summer and to visit us as well pleases us very much, and we request you to grant us the honour of your attendance certainly. Of your new splendid work, Das System der Medusen is the first volume already in our possession, and we do rejoice in being able to order immediately the second volume, when it is published, because your works are for our aims in replication both in description and in figures the most excellent and suitable among all books. Again friendly thanking and hoping that we see you soon in person, I remain with friendly greetings from my father and myself, With most excellent respect, Your devoted Rudolf Blaschka
The strong influence of Haeckel also turns up in the Blaschkas’ fascination with siphonophores. For example, take the Blaschkas’
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Portuguese-man-of war, complete with attached swimming bells and the dangling lures that are modified polyp stages (page 42). In addition to his interest in the developmental sequences of animals, Haeckel had an unusual interest in the division of labor that some groups like the siphonopohores and the hydrozoans show. Our glass collection includes representations of both themes, illustrated by the siphonophores. We have several series in glass showing different developmental stages, but the siphonophore version stands out in depicting stages that I’ve never seen before and that would not be easy to find in the wild. Each of the tiny sculptures in the series represents one of five stages in the siphonophore’s development, from tiny ciliated larvae to the process of budding the different polyp types that produce the multiformed adult jellyfish. The Blaschkas also designed models to show the complex variations in the division of labor within each animal. The Apolemia must be the most stunning glass in our collection, both for its size, complexity, and sheer compositional brilliance. The glass figure of Rosacea, however, comes closest to showing the actual nematocyst lures dangling down from the feeding and reproductive polyps (page 47). The models of Rosacea, Velella, Halistemma, and manof-war all show spectacular examples of division of labor; one can see the specialization of each individual zooid, or unit within the colony, that is responsible for the animal’s defense, feeding, or reproduction (Mapstone 2014). A watercolor of Halistemma rubrum depicts the basic form of a living siphonophore—the large swimming bell that is the powerhouse for fast movement and the long dangling tentacles that are the deathtraps for all manner of small shrimp and even fish, each tentacle capped with a deadly, red-tipped, neurotoxin-loaded harpoon. The differences between the flotilla of propulsive, swimming bells and the vast trailing
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armature of tentacles is easy to see, but harder to make out are the feeding polyps, nestled amid the warrior and reproductive polyps. The beauty of these creatures aside, there is a darker part to Haeckel’s interest in siphonophores. For him, a siphonophore’s physiological organization also represented a model of the hierarchy of social systems; a siphonophore should not be viewed as an individual, but as a social unit, a “state.” In German, the word for “state” is Staat, hence the name Staatsquallen, or “state jellyfish” (Reiling 1998). In a “state,” all of the differentiated polyps and medusae contributed to the benefit of the whole: some specialized in feeding, others in reproduction or floating, and still others evolved for defense, with a stiff armature of stinging capsules. Haeckel presented the Blaschkas with a signed copy of his 1869 lecture on this subject, which addressed the division of labor in nature and in human society. This lecture laid the groundwork for the further development of Social Darwinism, a controversial philosophy that posits that persons and races are subject to the same laws of natural selection as those Charles Darwin described for plants and animals. This theory was the basis for promoting the idea that the white European race was superior to others and should rule over them. The chilling crux of the idea was Haeckel’s argument that a society’s level of culture stood in direct relation to the extent of its division of labor. According to Haeckel, primitive societies were characterized by “little division of labor” (Haeckel 1900). These ideas are believed to have catalyzed Germany to support an authoritarian state power and a rigid belief in eugenics that culminated in the horrific genocide carried out by the Nazis (Gasman 2007). We do not know how important these ideas were to the Blaschkas, or whether they shared Haeckel’s political as well as scientific philosophies. We are left only with the stories that history and art tell us.
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What I really hoped yet also feared to see on our dive in Liguria were Portuguese man-of-wars. Like others within the siphonophore group, man-of-wars are fish-eaters and can pack a punch strong enough to level a diver. In fact, a student of mine was injured during a dive fifteen years ago on the Yucatán Peninsula in Mexico. We were documenting coral reef health at a remote site near Akumal; we’d surfaced from a drift dive on one of our deeper reef sites when she began screaming that she’d been hit. A brightblue tentacle was draped across her arm, torn from the Portuguese man-of-war that had stung her. I peeled it off, hoping she didn’t have other stings and would not go into allergic shock. It was a stormy, wind-filled day and in the high seas it was hard for our boat to find us. It felt like hours that I looked for the boat while calming her and hoping like I had never hoped before that she would not get worse or we would not get hit by other tentacles, invisibly deployed around us. We finally hauled her aboard the boat and poured vinegar on the sting, hoping the acidity would deactivate the neurotoxin protein. She was lucky. Other than a hugely swollen arm and a terrifying experience for us all, she was okay. In regions like Australia and the Mediterranean, an average of ten people a day are sent to the emergency room with life-threatening allergic reactions to the neurotoxin, and over 10,000 people a year are stung in Australia. Despite the dangers they pose, these are complex and beautiful creatures. Unlike the living version, our man-of-war in glass provides a safe opportunity to look closely at the parts that make up these very successful superorganisms. In contrast to many of the smaller transparent siphonophores, the man-of-war is unusual in having a bright-blue float that gives the animal buoyancy. It is
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also distinct in having three-to-five-foot blue tentacles that stretch from the bell and pinkish polyps that dangle from the gas-filled float. A close look reveals the collection of attached polyps, medusae, and poison-tipped defensive tentacles that make up the superorganism we call a siphonophore. It was only after our second Mediterranean dive, in the no-fishing preserve of Portofino, that I understood how over-fished most regions of the Mediterranean are and how this favors jellyfish. The waves were down when we reached the preserve, an hour’s motor around the headland. Anchored at the edge of a deep rocky reef, we slipped into water clear and sharp with high visibility. Big fish, little fish, red fish, blue fish! Fish of all sizes and colors surrounded us. As we descended to the bottom, Marco, the divemaster, flashed the hand signal for grouper, and there it was, nearly the size of Nathan. We were in an underwater fairyland, with rock walls carpeted with the Blaschka matches precious red coral (Corallium rubrum) and purple gorgonian (Paramuricea clavata). We swam through vast schools of anchovy and at least four other species of common plankton-loving fish. This small preserve is what the entire over-fished Mediterranean is supposed to be like! I can’t say for sure which of these fish might prey on larval or adult jellyfish, but there were definitely no mauve stingers at this site. Because plankton are notoriously patchy, I’d be a poor scientist if I argued that there had been lots of jellyfish the day before due to the lack of predatory fish at the shipwreck site and none today at this site because of the presence of fish. There could be several other explanations, including weather and chance, but the pattern did get me thinking about the widespread effects of over-fishing as a likely cause of jellyfish blooms. Ecologists describe increases in jellyfish blooms as a sign of a changing ocean. Jellyfish are one Blaschka group that will likely
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do well in warming oceans with fewer fish and turtles to control their numbers. But of course, they will not increase uniformly as a group with their diversity intact; rather, as with birds, some of the fairly common nuisance species—the jellyfish equivalent of starlings—will do well, and other examples of spectacular diversity will dwindle. So while there has been a lot of press about the danger of jellyfish taking over our oceans, I still contend diversity within this group will decline, while the population of particular species, like the mauve stinger in the Mediterranean, will increase. Fernando Boero, jellyfish expert and organizer of Jellyfish Watch, estimates that nuisance species have increased in the Mediterranean (Boero et al. 2008; De Donno et al. 2014). Many of our Blaschka pieces reside in this group. In the Pacific Northwest, Claudia Mills from the Friday Harbor Labs has studied the pelagic jellies her entire career. This region of the Pacific Northwest, tucked in protected waters near the junction of both northern and southern ranges of some species, is home to some of the world’s most diverse gelatinous zooplankton fauna. Some of us who have long worked at the labs remember well the days in the early 1980s when Osamu Shimomura was studying the Green Fluorescent Protein (GFP) that gives jellyfish their glow. Between 1961 and 1988, he hired fleets of kids to pull up bucketfuls of the crystal jelly (Aequorea victoria), a Blaschka match, from our docks. GFP is the glowing magic that is responsible for bioluminescence in many of the cnidarians and is particularly abundant in the crystal jelly, which used to dominate our plankton and still sails our seas. Shimomura and colleagues won a Nobel prize for the work done with the GFP of the crystal jellyfish. Claudia estimates that the crystal jelly is rarer now and would not support the level of research effort that was needed for Shimomura’s discovery. Claudia and others also observe that many
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Red-eye medusa (Polyorchis penicillatus) in Blaschka watercolor (left) and alive. This jellyfish has declined in the last decade in the san Juan islands (Mills 2001), although we were pleased to see several in summer 2015. Watercolor courtesy of the Rakow Research library, Corning Museum of Glass, BiB iD: 122338; photo by susan Middleton.
other jelly species have declined, although it is tough to track their status (Condon et al. 2012; Dong et al. 2010). Our red-eye medusa, Polyorchis penicillatus, a tall-belled hydromedusa and stunning Blaschka match (above), has also declined in the waters off Washington State (Mills 2001), although we were delighted to see a few in the summer of 2015. Further afield, many of the hydromedusae in the northern Adriatic Sea have declined, including two of the five species in the family Polyorchidae. What do we stand to lose? If we look to the Mediterranean, ground zero in our search for Blaschka matches, we know that marine vertebrates—back-boned animals like turtles, marine mammals, and fish (including bluefin tuna, sea bass, and hake)—are
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in danger of extinction from over-fishing, habitat degradation, and pollution, according to a report from the International Union for Conservation of Nature (see www.iucnredlist.org). More than forty species of Mediterranean fish are endangered (see chapter 8). Although we know that certain species of jellyfish are disappearing, and the diversity is diminished, it will be a long time before we have estimates on how many rare and spectacular jellyfish we are losing. Why? Pelagic animals like the jellies are difficult to catalogue because they are broadly distributed throughout the open ocean. This challenge has prompted a new global effort to track changing gelatinous zooplankton populations (Lucas et al. 2014). In the meantime, the species that are dangerous or prone to blooms, such as the mauve stinger, moon jelly, and Portuguese man-of-war, continue to sound the alarm that our oceans are out of balance. One thing is certain: the oceanic food webs that thrived 160 years ago, when Leopold Blaschka first encountered the magic of jellyfish on a nighttime sojourn across the sea, would have had far more predators on jellyfish, like octopuses, squid, and turtles, and enough sharks to have kept us out of the water.
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4. WORMS Ecosystem Engineers Undercover
ON A STILL DAY like this, the cliffed shore of Appledore Island
in Maine is a fine perch for early dawn coffee, with a soft-pinked ocean stretching west nine miles to the Portsmouth, New Hampshire, bridge. I’m teaching at the Shoals Marine Lab, a field station for the study of marine biology jointly run by Cornell and the University of New Hampshire. Although within sight of the mainland, it’s actually pretty remote; the RV John M. Kingsbury, a sturdy sixty-foot green and tan fishing boat, is our only way to reach the mainland. I see it bouncing ready at the dock. The big question is, will our band of twenty-something students be ready for a 6:00 a.m. departure? Last night, we’d reviewed the plan for the upcoming low-tide worm hunt at Creek Farm. The early departure was not a selling point for the millennials, but I hoped the prospect of hot showers and post-worm-hunt breakfast would tip the scales. There was certainly no danger of my oversleeping; I had gotten a 5:00 a.m. wake-up call from on-duty gulls outside my window, enthusiastically announcing to any of their brethren within earshot that the sun was rising. As I reached the dock, it was still devoid of students. I worried the tide might not wait for us and considered going after them, but then I saw the shuffling band of sleepy Cornell undergrads, buckets in hand, crest the The tentacled tubeworm (Pista cretacea). Inside its burrow, with only a few tentacles stretched across the sand or mud of its home, this worm would be easily overlooked. This glass rendition of a worm shows the full mass of feeding tentacles and bright red gills and the long line of bristles running the length of the body. Photo by Claire Smith.
hill—not alert, but with good-natured smiles, a bonus that early in the morning. Once again, the world felt good; we were about to embark on a muddy adventure to search out new frontiers of worm diversity from one end of a great tidal mudflat to the other. It’s easy to appreciate how the aesthetic appeal of a sea star or a jellyfish might inspire a person to capture it on canvas or in glass, but the true test of a great artist is to render the improbable as art. The Blaschkas did nothing less when they transformed a tubeworm into a mesmerizing object of art (page 68). The magic of their work lies in their artistic sense of design, coupled with a passion for natural history and the biology of form, as seen in the rendering of the tube-dwelling worm with red gills. Another example is the Serpula feather duster worm, which they re-created in both glass and watercolor (page 84), capturing perfectly the bright red tentacle crown and the red-striped operculum, a trapdoor that snaps shut to secure the closed tube. The even bigger prize for transforming the normal into extraordinary should go to their model of the burrowing lugworm Arenicola, since in glass it’s the normal worm that benefits most from an artistic eye. In their watercolor and eventually glass, the Blaschkas captured just the right curves and green body color to maximize the impact of the red gills and the signature dorsal blood vessel showing through the body, exactly as it does in a live worm (page 78). We know they thought deeply about the internal form as they worked, because in one Blaschka drawing of the lugworm, it is laid open to show a rare vision of how the external structures match up with the internal anatomy, showing the matched muscles, gills, and nephridia, which function as kidneys. The Blaschkas shape a surprising diversity of species, depicting even rare worms—or at least ones I didn’t initially recognize, like Pherusa plumosa. Pherusa, a sand-dwelling burrower,
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normally encrusted with sand grains or mud from eyespots to pygidium, is unrecognizable shimmering in glass. A more common worm, Perinereis cultrifera, the absolutely dirt-common clam worm, is majestic in its glass likeness. Nonetheless, the most arresting piece in our collection is a tube-dwelling terebellid worm, with its red glass gills and long winding feeding tentacles, which its living counterpart splays across the mud in search of food (page 68). Once again, we see the Blaschkas’ masterful ability to convey something more than the static animal. Here, they show the shimmering nature of the muscles playing underneath the transparent, flexible cuticle of the worm, each segment set off with tiny, red-studded parapodia, projecting like the stubby legs of a millipede. On each parapodium are small hooks in set rows, all facing backward, to hold tight to the burrow sides in case a predatory fish tries to pull the worm out. In all three of these worms, you can see the signature characteristic of marine worms—the projecting and elaborately ornamented appendages protruding from each body segment. The Blaschkas used mixes of colored glass on only a few of the glass animals, including the red gills of this worm, so that those who don’t have microscopes or time to look carefully can still appreciate that they are beautiful, surprising animals. Take my students. Some initially think worms are mud-dull, so it’s fun to see them sit up with interest when I share the range of worm biodiversity that exists. My lecture begins with the very consistent, logical layout of the long snake-like worm body plan, but then it’s juxtaposed against the shocking variations on this simple theme. I compare the variations in massive jaws and huge bristly appendages of the vicious, mobile, predatory bloodworms, and then we consider the differences of the array of sedentary tubeand burrow-dwelling worms. Some great families of mobile worms depicted by the Blaschkas include the clam worms, bloodworms,
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and bristle worms. To see the mighty, rather horrific curved black teeth at the end of the bloodworm’s proboscis, and to know they are armed with venom glands, makes you very glad these mobile predators are smaller than we are. However, some of the clam worms can reach two feet in length and have big jaws. The diet of these mobile worms includes other worms, corals, and small crustaceans, with some plant matter mixed in. Sedentary tube- or burrow-dwelling worms, on the other hand, are less ferocious but come in stunning colors and tentacle shapes. These worms are of several types, depending on whether they filter plankton from the water column with bright plumes of tentacles, or dredge through the sand and mud with ciliated strand-like tentacles that can stretch three feet across the bottom, or simply eat and process mud, like the lugworm. The Blaschka watercolor of Spirorbis spirorbis, a very diminutive plumed worm no bigger than a ladybug, magnifies it to the scale of a tiger. Spirorbis builds a hard, white, spiraled tube and is so tiny that most people wouldn’t even notice it in nature. Yet this is no ordinary earthworm—like the serpulid tubeworm, Spirorbis is topped with a spectacular red plume of tentacles used to filter plankton from the sea. When the tide is out, the tentacles are withdrawn, and only the innocuous white spiral is seen attached to rocks throughout the Gulf of Maine or even in the harbors of Boston and San Francisco. The Blaschkas’ watercolor shows the worm pulled from its tube, revealing more than the brilliant tentacles and tiny hooks that hold it in place within the tube, and the eyespots that cause the tentacles to flicker in and out with shadows. The watercolor also shows the eggs and frilled, eyed larvae that are brooded by each mother worm inside her tube. I am impressed that the Blaschkas knew these details of the tiniest worm, holding close her brood of squirming larvae inside delicately sculpted porcelain tubes. Our
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glass model of the sand worm, Pista cristata, is quite sensational, showing both the diminutive tentacled tubeworm and its gem-like case made of glass sand grains (below). Sally Woodin, a professor at the University of South Carolina and one of the world’s experts on the ecology of burrowing worms, tells me this worm can form large beds in places like Coos Bay, Oregon, with emergent ends of the tubes marking each burrow. A lot has changed in the 150 years since the Blaschkas spun their crystal creatures into being, including not only their conservation
Worms in glass (clockwise from left): Pherusa plumosa, Nereiphylla paretti, and Pista cristata alongside the sand grain tube it constructed. Photos by David o. Brown (Pherusa plumosa) and Gary Hodges.
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status and range in today’s marine environments, but also large upheavals in taxonomy. Bonellia viridis, our green spoon worm, is an example of the latter. In the Blaschkas’ day, it had its very own phylum, the Echiurida. The advent of modern molecular biology, however, downgrades the importance of its exceptional morphology and shows us that it is, instead, part of the fantastic variation within the vast phylum of annelid worms. On the upside, it may have lost its own phylum, but it hasn’t lost detectable ground in its distribution and abundance. The glass example we have in the Cornell collection is a female; the male is tiny, as small as a rice grain, and rare. He lives on or even inside the body of our larger girl. She lives in burrows in the sand and eats small animals or detritus. Her biggest feat is the production of an extremely toxic green pigment, bonnelin, which is capable of paralyzing small invertebrates and killing bacteria. It is so potent at killing bacteria that it is being researched as an antibiotic with applications for human health. What the Blaschkas could not have known is that both the nature of that chemical as well as sex is determined by the environment in which a baby worm finds itself. If it hits an abandoned patch of bottom, it turns into a female. If it lands near an existing female, the poisonous green pigment in her skin induces it to become a male (Jaccarini et al. 1983). This kind of sex-differentiating mechanism is thought by scientists to regulate population size. Considering what we have to learn from this diminutive but complex animal, it’s refreshing to know that it’s still common in our seas and widely distributed from the Mediterranean to the Atlantic and Pacific Oceans. My students, too, are heartened to know that the Age of Discovery is not over when it comes to searching out worms in their native habitats.
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As the Kingsbury inches us to the Creek Farm dock on the mainland, we are all anxious to get to square one for our worm hunt: an expanse of mud the size of two football fields. We’ve had to wait for a decent low tide, and it’s the first time off our very small island in two weeks. My student Reyn, always the organized one, remembers to grab the buckets and shovels as we step off the boat and head ashore. The tide flat, a vast expanse of brown mud, stretches before us, down to the glass water’s edge, with its usual muddish ocean smell, like a warm pond. Although the ground looks solid, I know differently. About halfway across, we hit the sucking mud and down goes the first student, tripped by a footfall that didn’t come loose. Although falling in the stinking mud could be viewed as bad, it comes with the territory for this group and only adds to the quest. Brad stands by to help Phoebe up and I watch nervously, hoping he won’t push her back in and start a mass mud fight this early in the trip. We slog through sucking mud to the water’s edge, eager to get as low on the tide as possible and start the dig. When you slow down to look, the mudflat is peppered with holes, burrows, and casts of all shapes and sizes. Casts are rather artful loops and even small volcanoes of coiled sand deposited by the worms after they have removed every bit of food value. We have a few tricks at our disposal to search out these unseen critters. First, it’s important to know what burrow or cast each species makes, and second, to dig fast to catch what lurks beneath. The third trick is to not sever your worm with the tip of the shovel or by pulling it too fast from the mud; worms have small, sturdy hooks for holding tight to the sides of their burrows. By the third hole, we are tired of finding just clams at the bottom. The point of this biodiversity class is to teach the lore of the mud, to recognize who makes the different-shaped and -sized worm and clam holes. We have three
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The parchment tubeworm (Phyllochaetopterus major) in glass. We found a similar chaetopterid in False Bay, san Juan Island, and on mudflats in Portsmouth, New Hampshire. Photo by Gary Hodges.
big goals on this dig, and they all involve worms. We need to find large clam worms, large burrowing lugworms, and something a little rarer, the parchment tubeworm, Chaetopterus variopedatus. David Brown calls our glass lookalike, Phyllochaetopterus major, a dragon (above). Its shimmering purple and gold likeness is indeed dragon-like. We won’t find the exact match, since P. major is a Mediterranean endemic, but Chaetopteris variopedatus is a close equivalent.
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We are finding a lot of clam worms and they are really beautiful specimens—the archetypal worm, with a long greenish body that’s studded in every segment with paired appendages called parapodia, each ornamented with stiff, bristly hairs. This is as good as it gets for a worm—highly muscular and with versatile parapodia for burrowing, crawling, and paddling through the water. These mighty mobile worms, which can reach up to a foot long, are made for hunting smaller worms. They have highly developed sensory organs on their heads—tentacles loaded with chemo- and mechano-sensory organs, eyespots, and grasping jaws. Suddenly, Phoebe yells, thrusts her hand into a hole, and slowly pulls out an impressive clam worm: eight inches of writhing Alitta succinea, bristling parapodia flashing in her hand. What Phoebe hadn’t realized is that these worms have really big jaws, and the clustered students scream as the black jaws pop out on the end of a sizeable proboscis, and Phoebe drops the worm. So it goes as the sun and steam rise over the mudflat: dig, yell, scream as each new worm surfaces. The really fun thing about a worm dig is the diversity we find; along with the clam worms, we also collect five different species from three different phyla: ribbon worms, flat worms, shimmy worms, acorn worms, and bloodworms. But our three other prizes—the parchment tubeworm, the calcareous tubeworm, and the lugworm—have so far eluded us, so we move on and try a different type of hole, one with a mud casting at its entrance. Soon enough, a bigger yell goes up, and Brad pulls the giant of all lugworms out of its deep burrow. This master burrower is eight inches long and designed like no other worm for the job of burrowing: a powerful ram-jet proboscis and a smooth body mostly lacking parapodia, except for rows of hooks on fleshy ridges, designed to grip the edges of the burrow (page 78). At first glance, it looks like a very plain brown worm, but on closer inspection, it’s actually iridescent green with a pair of bright
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Burrowing lugworms in the family Arenicolidae: Blaschka watercolor (left) and live (Abarenicola pacifica). Abarenicola pacifica is common on a mudflat near my house on san Juan Island. Watercolor courtesy of the rakow research Library, Corning museum of Glass, BIB ID: 121483; photo by Drew Harvell.
red gills on its front segments. It looks much like Leopold Blaschka’s watercolor version. This is not a carnivore; it has none of the monstrous jaws found on species like the clam worms. Instead it has a powerful proboscis that excavates u-shaped burrows by first ramming the sand like a pile driver powered by strong muscular contractions, and then irrigating with a water current. It feeds like your basic earthworm, by ingesting and processing mountains of sediment and sucking organic matter off each tiny sand grain. Unlike the inside of our jellyfish, which has only two tissue layers and no real organs, these worms are packed with every organ an animal could want—high-pressure circulatory system, several pumping hearts, pharynx, gizzard, stomach, intestine, excretory system, reproductive system, and bright red gills that act like lungs.
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My students are insatiable diggers, inspired by our high discovery rate, but we still don’t have a parchment tubeworm. To find them, we look for half-inch-diameter, flexible, chimney-like tubes on the mud surface. Although the expanse of tide flat looked homogeneous to us at first, once we start sampling, we find that the different worm types are quite distinctly zoned, with acorn worms, lugworms, and clam worms all found in slightly different tide heights and different textures of mud. We just haven’t found the parchment tube neighborhood yet. Then, from behind me, Reyn asks quietly, “Is this a parchment tubeworm?” It sure is! He shows me a six-inch worm, Chaetopteris variopedatus, encased in a soft brown parchment tube.
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Finding that delicate, rather exotic-looking worm in the mud of my native New Hampshire reminds me of my most thrilling worm sighting. David Brown and I were on a night dive off a remote shore in Wakatobi, Indonesia. The dive had not started well. We were picked up on a dark, windy beach, having signaled to a small boat with our lights, as if for a clandestine drug deal. Our captain then gunned the boat out through the surf, racing in the dark for a familiar gap between two small, rocky islands. Suddenly, our boat jolted to a stop. Someone had set a net across the gap, and our engine was ensnared. The captain and our dive guide, Jardeen, cursing in the dark, struggled to free the engine before the wind and breaking waves tossed us onto the nearby rocks. Finally, Jardeen jumped over the side and cut us loose. With what seemed like only feet to spare before hitting the rocks, the engine roared to life and we were on our way to dock with the mother ship, Patuno, which would serve as our dive platform. Once we were geared up and underwater, it still wasn’t going well: the seas were rough,
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a bit murky, and the site was either dynamited or storm tossed. We made our way across a shallow slope, weaving among a mixed jumble of overturned coral heads. There was a current moving us along, and captured in the beam of our flashlights were all the usual suspects: colorful fish and anemones, lionfish leering from ledges, crabs scuttling around the broken coral, and a lot of sand in between coral heads—a sign that coral cover was low on this impacted site. Suddenly, it got vastly better. Above the damaged coral, our lights picked up hundreds of foot-long animals undulating in the water like party streamers, swimming above the reef. Then we were in the middle of it, engulfed in an explosion of these streamers, jetting chaotically from reef to surface. I knew in a second of absolute wonder that these must be the mythic palolo worms. I would not have dared dream that we could be so lucky. We were caught in the middle of a huge spawning aggregation of these worms. Being in the middle of this felt like being in the etching by M. J. Schleiden (from Das Meer) where the ocean is dominated by every type of worm, including the swimming palolo, with weirdly metamorphosed segments. Palolo worms normally live quiet lives sequestered in branched burrows in the bottom sand. Most of the time, they look like an earthworm, a smooth-bodied worm with only small bristles on each segment, used to grip into their burrows. During their reproductive season, they make a dramatic metamorphosis to a large paddled swimming worm called an epitoke. Driven by hormonal changes and precise environmental cues, including the full moon, they swim toward the water surface. Then the gametes explode from their bodies to create a soup of swimming sperm seeking out ripe eggs. It’s not life’s end for each swimming palolo worm, because it left its head behind in the burrow to regenerate a new tail. But it is the beginning of the next generation of baby worms. David was
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beside himself with joy, filming the streamers, lit chaotically by his bright lights. I couldn’t wait to get back to my Blaschka collection and check to find if we actually had a palolo worm, since I had never imagined we’d have the luck to run into a spawning aggregation like this. Sure enough, the Blaschkas are always ahead of me and I found the worm watercolor in the Rakow Library at the Corning Museum, its modest form in watercolor belying its spectacular biology.
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Understanding how worms are faring in today’s oceans is what we call a knowledge gap. For one thing, it is hard to keep track of the myriad name changes in all the invertebrate groups, but I certainly had the most difficult time updating species names with this group. Scientists must have the correct scientific name to be able to follow the fate of any species. Not only have over a third of the species names changed since the Blaschkas created their models, but it feels like a third of the species names I learned as a graduate student have also changed. In addition, there are only a few studies showing how any worms are affected by warming or other climate factors. Sally Woodin has studied changes in worm distributions in Europe and the Pacific Northwest. She had her start as a graduate student right outside my front door, studying worms in the tide flats of False Bay, on San Juan Island. More recently, she studied a common species of subtropical lugworm (Arenicola sp.) in Europe that is expanding its range northward with warming. The lugworm Arenicola sp. is a boreal species that is disappearing from the southern part of its range in Portugal and is increasingly rare in the Spanish Bay of Biscay (Wethey and Woodin 2008; Wethey et al. 2011). It is particularly sensitive to warming because
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newly recruited juvenile worms are killed by high temperatures on low summer tides. What about impacts from ocean acidification? There are large groups of worms, like the clam worms, that freely spawn their eggs and sperm, and those from locations like the Pacific Northwest that are impacted now by great upwellings of acidic, corrosive water may suffer reduced fertilization success. Many worms, for example the lugworms, also lay egg cases in their burrows, in which tiny embryos develop into swimming or crawling larvae. We will likely soon have research that will tell us what to expect for acidification impacts to these potentially vulnerable egg cases. It is hard for biologists to track and identify what is causing silent shifts under the mud. It will matter. Although worms are often unseen and seem quiet, they dominate soft sediment bays and play a large role in the economy of this shore. Some marine worms are just like earthworms and seagrasses in that they function as ecosystem engineers. Ecosystem engineers are species that create, modify, or maintain habitats for other species and thereby amplify biodiversity. Some engineers, like the lugworm, bioturbate, processing miles of mud and, in so doing, bring surface oxygen and organic rich sediment to deeper anoxic layers. Others, like the sand mason worm (Lanice conchilega), are stabilizers, preventing sediment erosion and increasing refugia from predators, much like seagrasses do (Woodin 1978, 1981). One of Cornell’s most beautiful glass pieces, the tubeworm (Pista cretacea) with the bright red gills, is related to the sand mason worm, which forms large reefs stabilized by its tubes (Godet et al. 2011). One of the largest of these reefs in Europe is in the bay of Mont Saint-Michel in France, a vast sandy bay governed by large tidal currents. The sand mason reefs are distinctive enough to be mappable by aerial photography and in 2002 covered an area of
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approximately 475 acres, which is just over half the size of Central Park in New York City. In this huge area, there are densities of 6,700 worms per square meter (Godet et al. 2011). That is a lot of worms, and they have a huge ecological impact in that they both churn up organic material and stabilize the sediments. They’re a conservation concern because of their importance and their vulnerability to coastal disturbance. Another favorite glass piece, Serpula vermicularis (page 84), is also considered an ecosystem engineer (ten Hove and van den Hurk 1993). In Loch Creran, Scotland, the intertwining tubes of Serpula form small, hard, connected reefs that can be a foot and a half tall and almost two feet wide. Serpulid reefs in shifting muddy bays form vital stable habitat for other species, such as the 276 taxa that were identified from ten reefs in the marine protected area of Loch Creran. Serpulid reefs have been identified as a priority habitat by the UK government’s Biodiversity Action Plan (Chapman et al. 2012). Worms are also an important food source in the economy of our oceans and in some cultures. Most commercial fisheries of the world are based on fish that rely on worms for food. Worms are the link that can turn poor-quality food, like mud, into valuable human food, like fish. Worms are even a direct food source in some cultures. For example, the palolo worm spawning aggregations are a huge protein source and delicacy for Samoans, who track the lunar-phased spawning and go out on dark nights to harvest the egg-laden worms. Worm-like invertebrates cover a large swath of invertebrate diversity (annelids, nemerteans, nematomorphs, nematodes, platyhelminthes, priapulids, and molluscs—shipworms and vermetid gastropods), but in spite of the evolutionary success of their body plan, they are relatively understudied (Fisher et al.
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Serpula vermicularis in glass (left) and a Blaschka watercolor. This species is circumglobal and is commonly seen in both the Atlantic and Pacific. Photo by David o. Brown; watercolor courtesy of the rakow research Library, Corning museum of Glass, BIB ID: 95570.
2011). Segmented worms, the annelids, are currently the most diverse of the vermiform phyla, and annelids follow arthropods, molluscs, and fish in numbers of total species described by scientists (Warwick and Somerfield 2008; Costello et al. 2010). The International Union for Conservation of Nature is attempting to catalogue the global biodiversity of spineless animals. Currently, the likelihood of our detecting a problem in invertebrate biodiversity is 20 percent, compared to 80 percent for ray-finned fishes
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(Fisher et al. 2000). We have a problem with how little we know about conserving this component of biodiversity that lives right in our watery front yards. This is not something that requires rocket science; 160 years ago, the Blaschkas recognized and celebrated the central importance, the diversity, and the wonder of worms, yet to this day we have not figured out how to catalogue their changes in biodiversity.
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Back at our mudflat, the tide is beginning to take back the coastline, reducing our range to a narrow ribbon. We are now up to seven different types of worm, but I want one more. I want the Blaschkas’ serpulid worm, with its bright feather duster crown of tentacles and the trapdoor that closes off its calcareous tube. We found its tiny cousin, the two-millimeter-long spirorbid worm, with bright red tentacles and operculum, living by the hundreds on rocks and algae, filtering plankton with its powerful ciliated tentacles. It’s now 10:00 a.m., the point at which the students are usually pushing to explore the historic Creek Farm building in search of a warm breakfast and showers. This mud-encrusted group, some of them splattered from head to toe and sporting mud sculpture on their faces, refuses to leave the hunt and keeps digging, hoping to find one more new worm. Finally, the rising tide drives us off the beach, and after a successful breakfast and long, hot, showers (the first non-navy shower in weeks) we tramp back to the boat for our return to Appledore Island. As the others load up, Reyn, Courtney, and I crouch down and reach underneath the dock to pull up handfuls of critters to see what new ones we can find. Our yield is a bucket packed with anemones, mussels, feather worms, sea squirts, all abundant here,
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and crawling with even more new families of worms. Best of all, we find a few bright-colored sea slugs that are perfect Blaschka matches. And then, tucked so tightly in among the mussels that we almost missed it, is our long-awaited prize of the day: the serpulid tubeworm, a perfect match to our glass figure (page 84). It doesn’t look like much pulled into its tube, with the trapdoor shut, but we celebrate the long hard hunt for a species we thought would be common. We climb into the boat, still muddy but pleased that in this moment, the fate of this vast and diverse group of unobtrusive invertebrates is better than expected.
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5. SEA SLUGS Fire Stealers of the Deep
OUR WOODEN FISHING BOAT, Patuno, creaks and sways as we mo-
tor from the 500-year-old port of Wanci, tucked in the Wakatobi Islands of Indonesia. This marine national park is in the Coral Triangle, at the center of ocean biodiversity, rich in high numbers of species, from corals to fish, and home to many Blaschka lookalikes. Patuno, with her handcrafted wooden hull, twentyfoot-wide deck, and truncated stern, is like many of the remaining Indonesian Phinisi boats, designed in the 1500s with mast and sail and retrofitted more recently for motorized travel. We are headed for the reefs adjacent to the tiny island of Kapota, hoping to find a thriving diversity not just of sea slugs, but also of octopuses, squid, and cuttlefish—all of which were abundant here during the Blaschkas’ era. It’s easy to see why sea slugs are a group the Blaschkas singled out. Consider their unusual mix of colors, from bright reds and canary yellows to soft lavenders, leafy greens, and the biologically rare chrome blues. With their elaborate patterns of stripes, spots, and deadly feathered armor, these predatory dragons light up the deep despite their diminutive size. The smallest among them is no bigger than a ladybug. The Blaschkas captured every tiny detail.
Spotted sacoglossan (Caliphylla mediterranea) in glass. We didn’t find this very small sea slug, but it has been recorded within the past two decades on other checklists, including that of Riccardo Cattaneo-Vietti and Ferdinando Giovine (Cattaneo-Vietti and Giovine 2008). Photo by Guido Motofico, courtesy of the Natural History Museum of Ireland.
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Of the 569 Blaschka sea animals in Cornell’s collection, approximately 94 are models of these charismatic little creatures, known as nudibranchs. As Prometheus stole fire from Zeus, so these animals steal the stinging harpoons from their prey—anemones and jellyfish—and zip them into their own backs as co-opted weapons of defense. But unlike Prometheus, evolution has diversified our nudibranchs and they are favored through eternity for the theft. They thrive in the cool waters of the Mediterranean and British Isles and are most diverse in the warmer oceans of the world, including here in Southeast Asia, where I am looking for the more unusual tropical ones. There are over 700 species populating the Coral Triangle, and I’m hoping to find lots of living counterparts to the Blaschkas’ beautifully crafted replicas, but I am only cautiously optimistic. Like many ecosystems around the world, Indonesia’s once-rich marine habitats have been bedeviled by human impacts. Degraded by over-fishing and over-use, still-living reefs are littered with lost fishing gear, including lines, nets, and trash bags. Beyond that, vast stretches of standing corals, overcome by coastal pollution and too-warm oceans, lie dead and bleached, the weathered bones of a once vital ecosystem. The rich spectacle of colorful sea creatures that once depended on this environment is likewise absent, relegated to pockets of still-healthy reefs in the more remote waters of Indonesia’s less populated islands, or in protected national parks like Wakatobi’s marine preserve. Of all the problems plaguing Indonesia, however, blast fishing with bombs is the most immediately destructive. Not only do nitrogen-fertilizer bombs destroy the very framework of the reef by blowing it to smithereens, but they also remove the richest ocean habitat on our planet in the actions of a single night. It’s worrisome to me that the level of destruction from blast fishing only seems to grow with each new visit I make to Indonesia, while the
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public and many conservation managers on the outside think it has been reduced, since it is technically illegal. The only upside is that it’s also the most potentially fixable threat to marine life, since Indonesia has already legislated it as an illegal practice and, with enough resources and social programs, surveillance and protection could curtail it. This seems a far easier fix than expecting all the nations of the world to immediately adopt a carbon-reduction treaty to reduce ocean warming and acidification. My hope is that the data we gather here will help with biodiversity conservation and the development of new approaches to sustaining the lifeblood of biodiversity. But it’s difficult not to be moved by the terrible destruction in this rare and beautiful place. The rate and range of destruction cannot be overstated. I was about to see firsthand a region of coral change from pristine to devastated in the length of a football field.
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Wakatobi is in the heart of the Coral Triangle, where the biodiversity of all molluscs is high compared to the Caribbean. There are approximately 6,000 species of nudibranchs worldwide, in a dazzling diversity of colors and shapes, and approximately 151 are described in the Caribbean (Garcia and Bertsch 2009). The biodiversity of the nudibranchs in some areas of the Coral Triangle is estimated to tip the scales at over 700 species (see www.seaslugforum.net) and includes bright spotted slugs like the one depicted by the Blaschkas (page 88). Wakatobi sits east of the great Wallace Line of terrestrial faunal divide, drawn in 1859 by the British naturalist Alfred Russel Wallace, that separates the ecozones of Asia and Australia. The Wallace Line was drawn with terrestrial vertebrates in mind—think panda bears to the west and kangaroos
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and koalas to the east—and it’s only recently that scientists have been able to verify similar divisions within marine species. Faunal boundaries can be zones of unusual diversity, since the animals and plants on both sides can creep across. I like to think of this area as the Glass Triangle, due to the fragility of its marine biodiversity in this modern world. I had dived Indonesia’s Wakatobi Islands three years previously and remembered it as a beautiful area, abundant with sea life. During that trip, I’d visited the Waha Wall, which we planned to revisit on our way to Kapota Island. As a Coral Reef Rehabilitation and Management (COREMAP) site, it is part of a series of over 400 small protected areas funded through the World Bank. The goal of the project is to improve stewardship of vital marine resources, like coral reefs, which are so valuable to the local economy through fisheries and tourism. When I’d last visited, the coral wall, which extends hundreds of feet into the ocean depths, was healthy and filled with bright fish and colorful coral. This time, however, we took a wrong turn and headed south toward town rather than north to the COREMAP reserve site. I hadn’t previously seen how small the oasis of the preserve really was. As we donned our masks and surveyed the site, close to houses on shore, there was no clue to the impacts we were about to see. Once underwater, we immediately noticed scattered stands of dead coral along the top of the wall, and a lack of bright fish. We dropped over the reef edge and encountered a monstrous old fishing net, ominous and algae fouled, wrapped around the once-living coral and stretching forty feet across the reef, suffocating whole sections. More intangible, unseen killers, like coastal pollution, had killed whole colonies of coral, leaving only the dead white skeletons as a ghostly calling card. Our job changed from one of seeing the rare and beautiful creatures the Blaschkas had idealized in
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glass to one of cataloguing things killing the reef. It was uninhabitable to the creatures we sought and we came up empty, seeing no nudibranchs, octopuses, or cuttlefish. These reefs and the biodiversity they house are not just a vital source of livelihood for the coastal residents, they are also world treasures, cathedrals to living biodiversity. Leopold Blaschka could never have imagined the devastation we would wreak on the habitats of his beloved sea slugs. I was disheartened by the evidence of our disregard for nature. I hoped that when we ultimately reached Kapota, we would find a more promising environment.
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Nudibranchs are part of a larger group of snails without shells that we affectionately call sea slugs. Put simply, sea slugs include sea butterflies, sea elephants, sacoglossans, and nudibranchs, and the Blaschkas captured them all in watercolor and glass. Nudibranchs are named after the Latin term for “naked gills” because they have no shell in the adult phase and their gills are often exposed as great colorful plumes on their backs (page 105). As a group, they are divided into different families characterized by specific body forms and prey types. For example, the aeolids have bright plumes on their backs; this is the group that can transfer weaponry from their prey, anemones, to their back plumes (page 95). Members of the dorid family, which includes the bright chromodorids we will see on our dive, are somewhat flattened and have a distinctive ring of retractable gills on their backs; they mostly feed on sponges and the lesser known bryozoans. Finally, the dendronotid family is a smaller group of often large nudibranchs with elaborate plumes and branched back sculpture. Most of the Blaschka glass nudibranchs are uncannily exact matches to the living ones.
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The variable neon slug (Nembrotha kubaryana) in Indonesia’s Wakatobi Islands, where it feeds on sea squirts. This specimen was an exact match for the Blaschkas’ glass model. Photo by David O. Brown.
In photographs, it’s almost impossible to distinguish glass from living. I started my career as a biologist by studying the predatory behavior of nudibranchs in the San Juan Islands of the Salish Sea, so I can well understand the passion the Blaschkas had for this group of ferocious sea slugs. As I tramped through tide pools, turned over rocks, looked under docks, and dove in the cold water of the Salish Sea, which teems with over eighty-six species of nudibranchs, I became captivated by their spectacular beauty and unusual biology. I think the Blaschkas, like me, were mesmerized by the exquisite watercolors of Joshua Alder and Albany Hancock, naturalists who described every possible species of British nudibranch in their taxonomic treatise of 1840. Their inspiring watercolor monograph is partly the reason the Blaschkas were so enamored of nudibranchs. For example, if you compare the Blaschka watercolor and the earlier Alder and Hancock watercolor of Dendronotus, the origins of the Blaschka illustration are clear (page 96). Or the brilliant red
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Facelina bostoniensis, a nudibranch from the aeolid family, in glass (top) and alive at Shoals Marine lab in New Hampshire. Photos by Kent loeffler (top) and Drew Harvell.
Facelina (above) and the red-spotted Doto, which my student, Reyn, documented in 2013 on Appledore Island in Maine (page 97). Both of these species were common 160 years ago in Britain, when Alder and Hancock were at work, and they were common in 2013 when I taught my marine biodiversity course at Shoals Marine Lab on Appledore Island in Maine. Even Ernst Haeckel, one of the most famous biologists of the nineteenth century, was mesmerized by the forms and colors of the nudibranchs, and we know that his watercolors had a big influence on the Blaschkas’ artistry. What were the Blaschkas thinking about the life of each species as they sketched, painted, and crafted them in glass? We know from their sketchbooks that they were careful scholars when it came to external anatomy and understanding how it was linked to
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The frond aeolis (Dendronotus frondosus) in a watercolor (top) and alive. From Joshua Alder and Albany Hancock, Monograph of the British Nudibranchiate Mollusca, 1845–1910. Watercolor courtesy of the Albert R. Mann Library, Cornell University. Photo by Drew Harvell.
The crowned doto (Doto coronata) in glass (left) and alive at Shoals Marine lab. Photos by Claire Smith (left) and Reyn Yoshioka.
internal anatomy. It’s unclear, however, whether they knew enough about natural history to recognize that nudibranchs are voracious predators and actively hunt anemones and sponges, or that they are exceptionally choosy. Biologists would call them trophic, or food specialists, because each nudibranch species often only eats a single species of anemone. Surely the Blaschkas knew that the nudibranch Aeolidia papillosa, still common today on both Atlantic and Pacific shores, was a deadly force, stalking the plentiful plumose (Metridium senile) and elegant anemones (Anthopleura elegantissima). I imagine they must have perched beside tide pools and watched the cream- and ivory-colored sea slug creep up on its anemone and then pounce on the column, rasping at its tissue with a highly specialized, sharp-toothed radula. The radula is the ribbon of teeth that is a distinctive feature of all molluscs, and the
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shape and size of the teeth change with each prey type. This is a tightly coevolved predator-prey interaction that has been playing out in tide pools for millions of years. Or consider the tiny nudibranch species Doridella steinbergae, perfectly matched in white color and boxy pattern to the single species of bryozoan that it eats, Membranipora membranacea. The life cycles of predator and prey are so intertwined that the larval stage of the nudibranch will only metamorphose from its planktonic form to begin bottom life when it finds this one species of bryozoan.
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I like to think that the Blaschkas were just as intrigued by the fierce machinations of these tiny creatures as I am. What would our own team find as we prepared to enter the rich waters off Kapota Island? Our captain edges Patuno close to the reef top adjacent to Kapota Island, hovering over the edge of a coral cliff that drops from three feet to hundreds, with no bottom in sight. Once underwater, I am immediately struck by the wealth of life that’s teeming here, unlike at Waha Wall. No trash or nets or broken coral. Instead, I am greeted by towering walls of reef coral festooned with sponges, soft corals, and crinoids. I am relieved to find clear water and bright biodiversity as we begin our search for the wily nudibranchs. I hope for a high diversity of nudibranchs, but some are as small as a caterpillar and hard to find. Lucky for us, my Indonesian diving guide, Jardeen, is a talented nudibranch hunter. Like many Indonesians in this remote place, he speaks only Bahasa and understands a smattering of English. So our relationship is built on gestures and actions, which is all one needs underwater. David is here, too, camera in hand, hoping to capture some animals on film
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as I try to catalogue them. The water is sharply clear, and the bottom is alive with 80 percent coral cover and hundreds of different species. We pause transfixed by fish in every color, size, and shape zipping around like small rockets. There are wrasses and clownfish and angelfish and butterflyfish. Within seconds, it’s easy to see there must be at least fifty species of fish. It’s a carnival of sea life, filled with an exotic and breathtaking mix of creatures. Striped sea snakes undulate across the reef; green turtles zoom by, unimpressed by our presence; giant clams gape open to reveal fluorescent blue-spotted gill covers; yellow and bright pink crinoids perch high on coral outcrops (page 140). We go deeper. Once we’re along the cliff at forty feet below the surface, the current picks up. As we start to drift ever faster along the wall, we watch the pattern of Indo-Pacific biodiversity flash before us. David struggles to capture on film the multitude of brilliant sponges, bright corals in a rainbow of colors, multicolored crinoids unfurling their arms in the current, and a myriad of coral reef fish. There are sharks around, but we are so focused inward toward the reef they could be dancing behind us and we’d never see them. But where are the nudibranchs? Surely, in this diverse ecosystem, we’ll find one. Suddenly, I hear a metal clanging underwater and know that Jardeen has found something exciting and is banging signals on his tank. Sure enough, there it is, a vivid flash of blue and orange nestled on the vertical wall of sponge, a rather tiny chromodorid nudibranch, much smaller than a caterpillar. It has a bright blue body with even brighter orange tentacles, called rhinophores, and bright orange matching gills (page 105). This relatively common chromodorid, Chromodoris annae, feeds only on one group of chemically noxious sponges and absorbs as its defense the active chemicals from these sponges that are distasteful to fish (see the Sea Slug Forum, www.seaslugforum.net).
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Nudibranchs also have large value thanks to their potential for housing new drugs. As tiny alchemists with unusual powers, they not only concentrate rare and valuable chemicals from their prey, but they also add new twists in combinatorial chemistry. Nudibranchs make chemicals so unusual in their biological effects that even the most seasoned chemists are left looking like amateurs by comparison. An example is one of the chromodorids that feeds on a sponge containing the chemical manoalide; it can biotransform the manoalide into different chemicals that display antimicrobial activity against human pathogenic bacteria like Escherichia coli, known as E. coli, which is common and can be deadly (Karuso and Scheuer 2002). Other nudibranchs, such as the Spanish dancer, Hexabranchus sanguineus, are a source of novel anti-cancer chemicals. Pawlik et al. (1988) have shown that Hexabranchus sequesters manoalide from its food sponge, Halichondria sp. The dancer then concentrates the chemical in its back, releases it in mucus, and even loads it as a defense into its egg masses. There is an entire field of natural-products chemistry, funded by the National Cancer Institute and other agencies, devoted to finding valuable pharmaceuticals in marine animals. In this search, nudibranchs have been a rich source of new chemicals with novel biological effects. Those who know about nudibranchs are fascinated and perplexed in turn by their brilliant coloration and clever chemistry and understand that they are, in many ways, comparable to the better-known butterflies on land. Caterpillars are larval butterflies and the ones that do the eating; they feed on particular, often chemically defended plants. For example, monarch butterfly larvae feed on milkweed and extract toxic chemicals (cardenolide agylcones) that defend them against birds that like to eat caterpillars. Like butterflies and caterpillars, the striking colors and
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shapes of nudibranchs are closely matched to their particular prey species; they are master chemists, using their prey’s toxic chemicals in their own defense (Paul et al. 1990), as well as making up their own toxic brews; and they have elaborate mimicry complexes with lookalike animals. For example, some large flatworms are colored with stripes that match the striking warning coloration of some nudibranch species. The evolutionary story of nudibranchs is again similar to terrestrial butterflies in their capacity for striking evolutionary radiations, guided by the bounds of their prey type. One of my fun finds in Wakatobi was a bright blue, orange, and black striped flatworm that mimicked a chromodorid nudibranch; they were side by side on a steep coral wall. Several species of flatworm mimic nudibranchs that are well-armed with chemical defenses. The flatworm is not chemically defended, but derives protection from fish predation by resembling a toxic nudibranch. One of the best-armed species among the nudibranchs is the fluorescent blue-striped sea dragon (Glaucus atlanticus, page 102). It’s an open-ocean nudibranch that feeds on such dangerous prey as the Portuguese man-of-war, the lovely Porpita jellyfish, and the by-the-wind sailor. Each year, 10,000 people in Australia end up hospitalized due to a reaction to the neurotoxin in the tiny barbs of the man-of-war. Yet consider how the sea dragon nudibranch, Glaucus, received her name, which refers to the poison dress sent to Glauce by the jealous Medea. Glaucus swallows whole the toxin-loaded harpoons of the man-of-war and actually passes them through her entire digestive system. Once ingested, she mounts them as armature on the feathery projections on her back. This qualifies nicely as a poison dress, although with barbs aimed outward. It took scientists years to figure out the sea dragon’s trick. She selectively ingests and transports immature stinging cells through her digestive system to small end pockets in her
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feathery projections (Greenwood 1988). They then grow to maturity on her back, to be used as hand-me-down weapons. As I navigate the deep waters off Kapota, I consider the threats to our trio as we seek out examples of these tiny weaponized slugs. These reefs are packed with dangerous fish and invertebrates and it seemed like there was a lionfish, moray eel, or sea snake in every ledge and crevice. It’s hard to say which is the most dangerous. Lionfish, which range from mouse sized to Chihuahua sized, have venomous spines. If you are stung, the neurotoxic venom won’t kill you, but it hurts like a man-of-war sting and can trigger lethal allergic reactions. Although moray eels don’t sting and usually prefer to hide in a crevice, they scare me more. If you accidently put your hand near one’s mouth, it can easily flay your skin with its recurved teeth. The big green morays on this reef are a foot wide and ten feet long. Black and white striped sea snakes, though reputed to have the deadliest venom of all snakes, are rather docile, and their mouths are too small to even grasp your finger. But that doesn’t stop me from being startled—they have an unsettling tendency to unexpectedly pop up from the reef into our faces. The most common danger among the envenomated creatures is the one without a backbone that I haven’t mentioned yet. Remember the cnidarians with their stinging cells? My hand was blistered from the stings of a fire coral colony in an earlier expedition to Raja Ampat and, on this dive, some unknown jellyfish got into my wetsuit and turned my shoulder into a red mass of thirtyfive swollen, super-itchy blisters. Stinging hydroids and jellyfish, by the way, are one more prey favored by the ever-resourceful
a sea dragon (Glaucus atlanticus) in glass (top) and in a Blaschka watercolor. These tiny predators live in the open ocean and prey on the Porpita and Physalia jellyfish, which are also Blaschka matches. Photo by guido Motofico, courtesy of the Natural History Museum of Ireland. Watercolor courtesy of the Rakow Research library, Corning Museum of glass, BIB ID: 95575.
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nudibranchs. In one of the snazziest biological tricks ever, they don’t get blistered stomachs from eating fire coral. Although scientists still have only part of the story, we know that nudibranchs somehow select immature stinging cells as they eat. They pass these through their stomachs and zip them into special glands on their backs. Here, as if they had always belonged to the nudibranch, they continue developing as deadly harpoons. This trick raises very large biological questions. How do the nudibranchs sort immature from loaded nematocysts in their gut? How do the nudibranchs slip these foreign cells past their own vigilant immune systems and adopt them as part of their bodies?
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Finding a small nudibranch in fast water flow on an underwater cliff takes some doing. Filming one takes even more finesse. I’d lucked out in finding and cataloguing a blue and orange Anna’s nudibranch, one of the chromodorid species I hoped to find. Now, David is trying to stabilize his macro lens to capture the tiny creature on film. He gently wedges himself against an outcrop without kicking or elbowing any delicate coral colonies or nudging any lionfish. One wrong move and a head of coral could be dislodged. This is tough duty for a man used to chasing big things like beluga whales and walruses. But unlike whales or even some fish, this animal with glowing gills is blissfully unaware that it’s being filmed as it searches the wall for its favorite food, sponges. David had barely reorganized from the tough job of filming when we heard another tank clang. This time, Jardeen had found Phyllidia, a blue, orange, and black nudibranch that feeds on sponges and exudes toxins deadly enough to kill fish in an aquarium. This would turn out to be the most common of the nudibranchs we found on our trip,
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and reassuring evidence that these diminutive invertebrates seem to be doing well in the healthier pockets of reef here. Across Indonesia, we have so far seen five different species of Phyllidia, separated by their color patterns, from black and white, to black and green, to blue and white and black, to mixing in yellow. As David lines up to get a macro shot, an ever-present lionfish scuttles beneath his arm. The next tank clang is mine to sound, as I’d found a couple of beauties. Tucked into an overhang on the wall is a Blaschka lookalike the size of a mouse: Goniobranchus leopardus, with splashy brown spots patterned like a leopard; nearby lurked
Sponge-eating nudibranchs in the Wakatobi Islands. (Top, from left) leopards of the sea: Goniobranchus leopardus and Kuni’s nudibranch (G. kuniei ) near Kapota Island; (bottom) anna’s chromodoris (Chromodoris annae). Top photos by Drew Harvell (left) and David O. Brown; bottom photo by Drew Harvell.
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Goniobranchus kuniei, with iridescent blue spots as bright as a peacock (page 105). Both of these join the ranks of the sponge eaters. Day by day, we catalogue the surprisingly resilient biodiversity of Indonesia’s protected reefs in the heart of the Wakatobi National Park. Every day there are new species of nudibranchs, more clown fish in different anemones, and an impossibly high biodiversity of hard corals, soft corals, sponges, and fish. I had come with a mission, and the results have exceeded my expectations, despite the fringe of denuded reefs I’d stumbled upon at the beginning of my trip, which were outside a protected area. As we’re settling into Patuno for a long ride back across the bay after one of our last dives in Wakatobi, David asks me a tough question, one he wants included in the film: What is the value of biodiversity? It seems easy enough to answer on the surface, but it’s one that plagues scientists and conservationists who often have to prove to governments, stakeholders, and the public why protecting delicate ecosystems is important. David presses further, asking if the number of species matters. Would it be okay if we had just one species of nudibranch instead of the roughly twelve we have seen and the probably fifty-five that we haven’t seen? David’s question would be easier to answer if he had posed it about economically important fish or corals, but there is indeed a story for the ecological role of nudibranchs, even if it’s tough to put a price on. Nudibranchs, as we know, are extreme food specialists—each species only eats one food. So different species of nudibranchs are not substitutable. For example, during a dive earlier in the trip, I had led an expedition to survey coral reef health in Raja Ampat and Bali. On the very over-fished reefs with high nutrient inputs, the corals were being killed and overgrown by a platoon of sponges, sea squirts, and algae. Sponges and sea squirts are
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the absolute favorite food of nudibranchs. So if you lose the one species of nudibranch capable of eating the extremely toxic and fast-growing neon purple sponge or the terrible green sea squirt, your corals might become overgrown with the sponge and the reef will be less sustainable. Indo-Pacific sponges and sea squirts are so toxic that few animals other than nudibranchs, a few specialized fish, and hawksbill turtles eat them. In Raja Ampat, nudibranchs were few and far between. We don’t know if it was because their predators—certain fish, sea spiders, sea stars, and even some turtles—were unusually effective, or whether other aspects of their habitat had become unsuitable.
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In talking about the prospects of sea slugs in the oceans of today, we have to look also to other sea slugs, such as the pteropods, or sea butterflies and sea angels, which get their name from the transparent wing-like projections that row them through the oceans as if in flight. I periodically see the Blaschkas’ exquisite sea angel, Clione limacina (page 108), flying through the water near my lab at Friday Harbor. This tiny but vicious predator, with transparent wings and a red glowing stomach, has keen senses and a sharp radula with which to hunt and tear apart the shelled species of sea butterfly. Ancient whalers called them “whale food” because although each pteropod is small, their flocks can dominate the plankton and are the food that feeds baleen whales. The shelled pteropods, or sea butterflies, are indicator species for the impacts of acidification. Ocean acidification is the lowering of pH that occurs when there is too much carbon dioxide in the water. The oceans absorb approximately a third of the excess carbon dioxide we emit, thereby slowing adverse effects like warming in our climate system. But
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Clione limacina, one of the fierce, predatory sea angels, in glass (top) and alive at Friday Harbor. Sea angels are called naked pteropods, since they do not have a shell. Photos by gary Hodges (top) and Reyn Yoshioka.
the carbon dioxide accumulating in ocean waters has decreased the average pH across entire ocean basins by 30 percent in the last 160 years. This has tipped the scales in acidic hot spots like the Pacific Northwest, making the water actively corrosive to the point that it dissolves the shells of animals like the shelled sea
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butterfly, which live its entire life in acid waters. The link between decalcification and ocean acidification wasn’t noticed until 2007. An oceanographer from California State University San Marcos by the name of Victoria Fabry, aboard a research vessel in Alaska, noticed that the shells of oceanic pteropods were pitted and thinning from the corrosive waters in her experiment (Fabry et al. 2008). This was the first indication that our climate-changed future was here in today’s seemingly clean oceans, affecting beautiful and important marine life in ways that we could actually see. Since then, the dissolving shells of sea butterflies have been joined by dissolving shells of larval oysters, with big economic impacts as a result. Recent work has shown an increase in the percentage of pteropods with pitted shells in acid-rich parts of the Pacific, and scientists found that the highest percentage of sampled pteropods with dissolving shells were along a stretch of the continental shelf from northern Washington to central California, where 53 percent of those sampled had severely dissolved shells. They suggest ocean acidification will disrupt the great oceanic food chains that start with phytoplankton and end with whales (Bednaršek et al. 2014). Unfortunately, the nudibranchs aren’t immune from the acid waters either (Davis et al. 2013). Although they lack an adult shell, nudibranchs, like all gastropods, have thin larval shells that are sensitive to levels of acidification. The nudibranch larva is called a veliger and its shell is made of aragonite, which is more sensitive to low pH than other forms of calcium carbonate. Scientists have been finding that the larval forms of many invertebrates, like the nudibranchs, have very delicate calcareous skeletons that are sensitive to the corrosive effects of low pH. No one has checked nudibranch shells, but larval shells of other molluscs begin to dissolve at pH 7.6, a level already reached in some areas of the Pacific
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Northwest (Byrne 2011). Ocean acidification is a diabolical threat that is increasing unseen, a lurking time bomb that explodes unpredictably in cold, upwelled waters like those of the Pacific Northwest, the Arctic, and the Antarctic.
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By the time our Kapota dive had ended, we had seen eight different species of nudibranchs. David had close-up videos of them all, each recording accompanied by a soundtrack of us laughing and muttering underwater at the ridiculous spots and stripes and colors on our slugs. Even before surfacing, the excitement of a perfect dive was shared as we all three were suspended weightlessly at our fifteen-foot safety stop, floating over the reef edge. We communicated in an underwater language of shaking and nodding our heads, our hands signaling “thumbs up” and “so big” at the riches of this reef. As we surfaced, David couldn’t get his regulator out fast enough to express how amazing the reef, the nudibranchs, and the clownfish anemones were. I was satisfied to see this brilliant whale videographer so pleased with finding the wily sea slugs, and the quiet Jardeen excitedly passing around the Indonesian natural history books to the captain and mate to show them the species we saw. The chatter continued as we warmed up with tea on the deck of Patuno, joined by an Australian couple who had come here knowing it was rich in sea slugs. “It was like a nudibranch circus down there,” the woman exclaimed. We brought two of our close Blaschka matches aboard and carefully placed them in a glass-walled tank so I could identify the species and snap some photos. Afterward, I returned them to their reef, grateful to have seen them. We had come a long way to find these fierce little sea slugs, and it was reassuring to know they
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still dominated this small place. I also loved seeing that dive tourists valued the sight of nudibranch circuses and would come to Southeast Asia with that as a must-see goal. However, as a group, the nudibranchs today are no doubt much harder to find than 160 years ago, as their habitat and prey are much reduced, and the practice of blast fishing is leveling the few safe habitats remaining.
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6. OCTOPUS AND SQUID Shape-Shifters under Pressure
AS WE HEAD DOWN the Big Island’s Kohala Mountain for a night
dive on the reef, David explains that if we’re lucky enough to find an octopus during our dive, he wants to capture footage of me interacting with it. Well, how does that work? I ask. Usually when I see an octopus, which is not often, I watch it for a while and then it jets off, shifts into camouflage mode, and I never see it again. David explains that he wants me to hold it, to herd it between my hands, and gently engage with it. Apparently, this is common among recreational divers, especially with inquisitive octopus who seem just as curious as their human counterparts. My training is to only touch or collect organisms we need for research, so it’s unusual for me to handle something like an octopus. Me: “But don’t they bite?” David: “No, they never do—it won’t bite you.” Me, very dubiously: “So . . . you want me to herd it and then pick it up?” David: “Yes, you’ll see how easy it is.” I figure our chance of finding an octopus is remote, so I decide not to worry about it. Our goal is to find the day octopus, Octopus cyanea, a visual match to our Blaschka common octopus (O. vulgaris) but now shown to be slightly different genetically (Kaneko
The long-armed squid (Chiroteuthis veranyi) in glass. Photo by Guido Motofico, courtesy of the Natural History Museum of Ireland.
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et al. 2011). The common octopus is widely distributed from the Mediterranean to Japan, but the day octopus dominates in Hawaii, where it is well established. Despite their name, day octopuses are active at night and so we might actually find one out hunting at night. We are also hoping to see the rarer and more beautiful nocturnal ornate octopus, which our dive guides, Denise and David from Blue Wilderness Divers, said they’ve seen at a particular reef on recent nights. We arrive at the boat, which looks mellow in the days-end light. We set out across the pink-lit sea to our dive spot off Hawaii’s west shore. We are happy to be heading out with Denise and David, since they have been helpful, knowledgeable partners in our Cornell semester program, teaching our students to dive, taking them into their business as interns, and even putting them up during their internships. As we tie up to the mooring in the dark and sort our gear, I’m skeptical that we’ll find either octopus, but I know there will be other interesting critters on the reef at night, and some of them may be Blaschka matches. Once underwater, we hunt with our headlights on in the pitch dark for over forty minutes. We scare up a fluorescent pink flatworm and a slipper lobster. As we nudge past a few sleeping reef fish, I note there are not many on this reef, which has been heavily fished. We are watched all the while by the glowing eyes of resident shrimp. Since my face is pressed close to the bottom, on the lookout for any good finds, I keep getting lost from the group. Suddenly, someone I don’t recognize swims through the darkness, grabs my arm, and drags me along. By now, I am pretty disoriented about where we are on this reef and I have no clue where we are going. Just ahead I see a large lighted glow from dive lights. There it is—the ornate octopus! Everything runs through my mind at once: disbelief that we have found it, delight that it is there, worry that it
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will disappear too fast. The octopus sits stolidly in the light of the camera, not too bothered by the attention. It’s an unusual shade of orange with bright white spots and dashes along all its arms. It’s beautiful. I tentatively reach out a finger to touch a tentacle. It touches calmly back with its suctioned tentacles, then scuttles in the other direction, but I easily herd it back between my cupped hands. All the while it watches me with large amber eyes.
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As I mentioned, my adventures beneath the surface all started with an octopus—a glass one (page 1). I remember it eyeing me from its case and I wondered, what makes this work of art like a being I want to spend time with? The Blaschka works have a presence and allure, a sensitivity and flair that reaches beyond the mechanical imitation of nature and becomes the gestalt of nature itself, the soul of nature. This comes out vividly in the cephalopods because they are the one invertebrate imbued with clear intelligence, perhaps even consciousness. The Blaschkas knew this when they put pen to paper to sketch their models. This common octopus, now restored, seems completely self-aware as she gazes calmly at me from her display case. The Blaschkas’ glass octopus models are infused with an eerie sense of consciousness because of the depth and expressiveness of the eyes. The artistry of these eyes came from long practice, because the Blaschkas’ very first works in glass were prosthetic eyes for humans. Today, at the Corning Museum of Glass, there are bins of different-sized prosthetic eyes that were found in the Blaschkas’ workshop, awaiting adoption by humans in need. Leopold and Rudolf ’s artistic vision captures complex details of biology that are sometimes little known even to me. Only recently
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have I looked closely enough to notice black, curved hooks bristling from the tentacles of one of our squid models (Ancistroteuthis lichtensteinii) like the poised claws of a cat, or the comical, Dumbolike fins of the chubby Rossia squid. The masterpiece of the cephalopods is the mighty Chiroteuthis veranyi squid, with long coiled tentacles exactly as Haeckel portrayed them in his drawing, and eyes shadowed in periwinkle blue (page 112). Even Haeckel’s dramatic, somewhat stylized rendition of Chiroteuthis does not show this mastery. Since I had never seen a living Chiroteuthis, in preparing for my TED Talk about our collection, I turned to Bruce Robison’s videos of the living Monterey Bay Chiroteuthis, masterpieces in their own right. I knew those long coiled arms were used for prey capture, but I didn’t understand exactly how they could shoot out so fast. Think about the mechanics of it: Those arms are at least four times the body length of the squid, perhaps ten feet long, and there are no bones for muscle to contract against. When humans punch, they use the mechanical advantage of muscles contracting against bone. To punch its arms, Chiroteuthis takes advantage of what we call a hydrostatic skeleton. The longarmed squid contracts muscles to increase its internal fluid pressure, allowing it to squirt out those arms at high speed and nab a passing fish. Squid also use a hydrostatic skeleton for jet propulsion—drawing in water from their siphon and jetting it out under pressure. The dazzling part of Cornell’s glass cephalopod collection, which includes thirty-seven pieces, is its diversity. We can walk through all the major groups within this class—eight-armed octopus, tenarmed jet-propelled squid (page 117), and eight-armed shapeshifting cuttlefish, then dawdle within the amazing diversity to view tens of species of each (page 118). To this day, Leopold and Rudolf give us the chance to see both common and rare species.
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the Blaschkas’ jeweled umbrella squid (Histioteuthis bonnellii) before (top) and after restoration. Many of cornell’s models are in this condition, from early years when they were not cared for. the transformation is magical when a talented conservator like Elizabeth Brill puts a model back together. although this species of squid lives deep in mid ocean and is not commonly seen, it does appear in the stomachs of dolphins and sharks, indicating it still swims our seas. photos by Elizabeth R. Brill (top) and Kent Loeffler.
The cephalopods past and present are all top predators: fast-paced, jetpropelled, active hunters of prey from crabs to fish. In squid, this active lifestyle is supported by four hearts that power a closed, high-pressure circulatory system—a far cry from the open, slow-moving circulatory system of their relatives the sea slugs and bivalves. We call cephalopods jet propelled because their speed is provided by the same muscular body wall that controls the powerful arms. They contract rapidly enough to create an enormous pressure change that jets them through the water. The actual mechanics of the stunning jet propulsion accomplished by the body wall and its multiple layers of spirally wound fibers and opposing muscles has long been a fascination for engineers (Kier and Smith 1985). The other part of the magic trick is the fastest electrical conducting system known in animals. The giant axon or nerve is beloved of neurophysiologists because it’s
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Cephalopods in glass (clockwise from top left): common clubhook squid (Onychoteuthis banksia), stout bobtail squid (Rossia macrosoma), elegant cuttlefish (Sepia elegans), fourhorn octopus (Pteroctopus tetracirrus), curly tentacle octopus (Eledone moschata), and blanket octopus (Tremoctopus violaceus). Photo of curly tentacle octopus by Claire Smith; photos of cuttlefish and blanket octopus by Elizabeth R. Brill; all other photos by Kent Loeffler.
large enough to study and it runs the length of the squid; at a millimeter wide, it’s the same width as spaghetti. Larger diameter axons have faster conducting speeds; at eighty-two feet per second, this is the fastest unmyelinated conducting axon known (Plonsey and Barr 2007, p. 109). Humans have smaller-diameter axons, but ours have a fatty covering, called a myelin sheath, that amps up the conduction velocities of our motor neurons to over 260 feet per second. In addition to jet speed and maneuverability, cephalopods have, by comparison to other invertebrates, an unprecedented sensory system: a camera eye that rivals the structure of the vertebrate eye, including our own. This is one of the big evolutionary puzzles—that such a complex structure as the camera eye could have evolved independently twice, in both backboned animals and cephalopods. While the brain of a squid, octopus, or cuttlefish is no larger than a pea, it does serve as a central processing center for this active, highly sensed predator. But the real marvel that I relate to most in communing with cephalopods is their level of intelligence. It’s been suggested that octopuses have, on average, the intelligence of a cat. This is easy to believe when they play games with you from a tank or underwater. A lesser-known member of the cephalopods are the argonauts, the pelagic octopus called paper nautiluses. In Jules Verne’s novel Twenty Thousand Leagues under the Sea, there is a wonderful picture of Jason on his ship The Nautilus, surrounded by a fleet of argonauts with their sails lifted. The ancient Greeks believed argonauts sailed on the water by using two of their arms as sails. Because of this, they named the mollusc after the sailors of the ship Argo. They were the sailors who went to look for the Golden Fleece in the famous Greek myth. The Blaschka watercolor of the male argonaut was initially a puzzle to me. I wondered why Leopold had produced such a small,
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exquisitely detailed watercolor of a very small argonaut. I thought perhaps it was a juvenile, but after some research, I learned he was portraying, to scale, the one-inch-long adult male argonaut. In contrast, the female is five times larger, lives much longer, and makes the brilliant white, paper-thin egg case that gives these octopods the name paper nautilus (page 121). Our stunning glass female is shown without her normal paper shell, but holding her flat egg cases on specialized arms. The paper nautilus, technically an octopus, is just one of four cephalopod groups that show this extreme size dimorphism between the sexes. Another example is the blanket octopus (Tremoctopus violaceous), which the Blaschkas also sculpted in glass. The males may be only an inch long, but the female can be three feet long. The tiny males in all these dimorphic octopuses do, however, have an interesting aspect to their biology that is included in Leopold’s watercolor of the male argonaut: a detachable heterocotylus arm, which functions like a penis. I have to admit the detachable arm was a new and surprising discovery for me. This heterocotylus arm breaks off from the male and actually swims by itself to inseminate the female (Orenstein and Wood 2015). I thought this was slightly unusual but wasn’t that surprised by it, since invertebrates have some extremely kinky sex by our standards. While on the topic of sex and reproduction, we need to discuss the Achilles heel, the weak link in the life history of all the magnificent, brilliant cephalopods. All of the females and many of the males are semelparous, which means they only reproduce once in their lives and then die (think Charlotte’s Web . . . ). This seems amazing to me given the degree of social interaction involved in mating and the enormous effort invested by octopuses in brooding their clutch of eggs. For example, our common octopus carefully ventilates and guards her tiny brood for between two and six
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a Blaschka watercolor of a male argonaut (left) and a Blaschka glass model of a female argonaut (Argonauta argo). Watercolor and photo courtesy of the Rakow Research Library, corning Museum of Glass, BiB id: 122439.
months, depending on where she lives, and then dies after they hatch. The male will die soon after he mates with her. Their lives are indeed often very short. Even the giant Pacific octopus lives only three to five years in the wild. Considering their level of intelligence and how little time they have to accumulate learned experiences, I reckon an octopus that could live to be twenty might well be smart and experienced enough to take over the planet. But of all the cephalopods’ remarkable traits, there is one that researchers are still trying to wrap their heads around: the ability to quickly shape-shift, or transform, from a rock to a piece of drifting algae. For example, cuttlefish are called chameleons of the sea because of their split-second color and shape shifts. Watching two cuttlefish together is like watching a conversation in color. In competing males, low mutters of muted shades change quickly to
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emphatic shouts of sharp, dark colors. Passionate love calls between mating pairs are shared in vibrating colors that wash along the body. It boggles the mind to see two conversations occurring at the same time on a single animal; I once saw a male cuttlefish crooning a colorful love call to a female along the side of his body facing her while simultaneously edging out a male with a sharp, jagged territorial display on the other half of his body. The rather serious octopus scholar Roger Hanlon made his audience laugh with the joke that this type of two-part conversation is evidence that males have been two-faced from earliest evolutionary time. The uncanny camouflage of octopuses and cuttlefish requires large but precise color and body surface texture changes. Sacs of yellow, red, brown, and black pigment called chromatophores are opened and closed by muscles that orchestrate instant, coordinated color changes. Muscular contractions change skin texture from as smooth as glass to as craggy as a drift of algae. The degree of shape and color matching of underwater objects is a conjurer’s trick. It includes all the color and shape changes and behavior that mimics exactly the object being imitated—for example, mimicking a coconut shell bouncing along the ocean bottom or a piece of algae floating by. Once, on a dive to a very scroungy reef near a fish farm in the Philippines, I saw a foot-tall piece of floating algae start to swim purposefully away and realized it was actually an octopus. Once we started to watch her, she gave this “Uh oh, busted!” kind of shrug and went through a frantic series of shape and color matches to everything around her, from rocks to algae to coral heads. How strange to realize that in this riot of color change, octopuses are, themselves, color blind.
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Octopuses in Hawaii. drew holding the ornate octopus (Callistoctopus ornatus) on a night dive (top) and trying to entice the day octopus (Octopus cyanea, a close match with the common octopus) from its den. photos by david O. Brown.
David was right—it is pretty easy to cage an octopus between your hands—at least until it jets off over your head. But it is easy enough to follow this one swimming off into the night. This time, as I herd her again, I’m braver and ready for the jetting trick. As she lifts off, I catch her gently in midair, almost like some large bird, except one with eight sticky tentacles. Holding her at eye level, I look into her eerie, knowing eyes (above). Then a tentacle slaps onto the
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front of my mask, and the octopus crawls up my arm. I feel like the octopus whisperer. This is the moment I fall in love again with the unexpected, otherworldly, and profoundly beautiful biodiversity in our oceans— this animal is so exquisite in form, so interesting, and so unlike anything else on the planet, it’s heartbreaking to know that we are systemically, and often wantonly, destroying it and its world. I relish all my invertebrate field experiences, but this one stands apart. Luckily for me, we’re going to dive again the next day. The strategy for our next dive is to be up before sunrise and in the water with the rising sun, hoping the day octopus will be venturing out. We arrive before the sun at our shore site on the wave-crashed Kona-Kohala coastline. It is always a bit tough to clamber over the sharp lava rock laden with heavy tanks and dive weights, but we make it underwater as the sun rises. The morning glow illuminates a crystalline seascape filled with bright yellow tang fish, autumn-colored coral heads, and large lurking trumpet fish. Looking for an octopus that doesn’t want to be seen can be a tough prospect, so I am prepared for a long hunt. It seems so improbable as to be fated, because within minutes of entering the water, I spot a dark brown smudge on the edge of a coral. The smudge ripples, transforming what at first looked like rock face into a footand-a-half-tall camouflaged octopus. I can’t believe that we are so lucky as to have found the exact animal we wanted right away. As we approach, the cat-sized octopus withdraws partly into its den. But it is bold and actively watches us, soon easing back up along the rock, tentacle by tentacle. It’s clearly curious, elevating periscoped eyes as high as possible to watch us from beside the den. As I move away, it eases out further, craning its eyes to watch. It’s quite comical. After a while, it
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settles and stays put, body flickering through a kaleidoscopic color change from beige to deep brown to a mottled paisley. I try to entice it out by running my fingers back and forth and then tapping on a rock, like playing with a cat (page 123). No dice. It eases up a little further from its burrow and cocks an eye, but no tentacle reaches out to sample my game. Meanwhile, trumpet fish, attracted by David’s camera lights, have gathered to watch the drama as David tries to film, laughing as he steadies the camera. I move away a bit to see what happens. No sooner do we ease back ten feet or so than the octopus, far larger than I had realized, lifts off its rock stronghold and jets across the reef. What a spectacle—a big octopus, in full swim with long tentacles trailing three feet behind the massive webbed body. In stealthy pursuit, we watch as it settles again to the reef, with a fast-paced race through its repertoire of colors, this time from brown to maroon to beige to vibrantly striped and back to brown. This is my chance. As the octopus lifts off again, I reach to catch it in midflight. After the easy time I had with the delicate ornate octopus the night before, I am unprepared for how strong this big one is, and there briefly ensues a bout of extremely uneven interspecies grappling. Through a rain of tentacled suckers, I try with two arms to hold eight. As if that wasn’t enough, we are both suddenly engulfed in a huge, blinding cloud of dark brown smoky ink. I can say from firsthand experience that inking is the strategy to confuse a would-be predator. This marine Houdini eluded me in seconds and was once again across the reef and into the safety of another den. David continued trying to film this, but as I looked over, we both flooded our masks laughing. He had just filmed a ridiculous
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spectacle of me rolling around on the sand with this octopus, ending with us both enveloped in ink and the octopus calmly jetting off. Although the dive ended abruptly, we left pleased to have found both of these octopuses so easily. Despite strong hunting pressures in the Hawaiian Islands, they seem to be doing well.
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Some of the other cephalopods fashioned by the Blaschkas are much smaller. The small sepiolid bobtail squid created by Leopold (page 118) is charming and was likely very common once in Italy. Indeed, my first encounter with it at the dinner table suggests it might still be quite abundant. I wanted to leave the table when I found an inch-long sepiolid nestled in the pasta on my dinner plate in Italy. I can see why it’s a delicacy, but I am now too in tune with the artistry and coolness of most cephalopods to eat them. The sepiolids of Hawaii, called the Hawaiian bobtail squid, perform what feel like miracles in their husbandry of bacteria and offer the animal kingdom’s most striking example of animal symbiosis with bacteria. Many squid are brightly lit with bioluminescence at night and it turns out that the light is provided by bacteria. Margaret McFall-Ngai, professor at the University of Hawaii, has spent her career studying the regulation of this symbiosis as a model system and the details are almost too good to be true. The bacterium is Vibrio fischeri, and it lives within a bacterial commune in specialized pockets on the bottom side of the squid. The bacteria are bioluminescent and form bright light organs within the squid. The awesome biology to me is that every morning the bacteria are vented out and have to be recultured by the squid during the day in order to produce the nightly light show. McFall-Ngai speculates that the daily release prevents the bacteria from getting
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the upper hand in the symbiosis. Leopold Blaschka undoubtedly knew that these squid were bioluminescent, but he could not have known it was caused by a symbiosis with bacteria and required careful cultivation by the squid in a special light organ, with its own lens and reflective surface to focus the light. This is another cephalopod I have not seen in the wild. I think again about the wonderful sessions the Blaschkas must have had with these creatures in the late 1800s. I imagine Rudolf Blaschka peering into tide pools and bringing back to his studio aquarium this bounty from the sea. I am mystified by the Blaschkas’ ability to so beautifully capture not only the correct anatomy of their subjects but also the nuances of their exact poses in glass. Leopold once said in praise of his son, “Tact increases with each generation.” How many artists describe their artistic endeavor as requiring tact? Leopold reminds us that they were doing more than simply trying to copy animals in nature; he thought about deeper issues in the way they created art, and he conveys this awareness in his description of Rudolf ’s ability. I think about the meaning of tact: “adroitness and sensitivity in dealing with difficult issues.” The nuance in the Blaschkas’ work is what makes this collection of ocean life great, their tact in selecting the right animals and their sensitivity in bringing them to life. They chose soft-bodied invertebrates that are extravagantly beautiful but poorly known. They didn’t choose turtles or sea stars or even crabs. Viewing their art is a process of discovering the rare and beautiful in the ocean. Cephalopods are the hardest group for me to characterize. These fascinating creatures are difficult to track down in the wild, and I am concerned for the future of both currently common and rare species. Observing their behavior, from their complex mating rituals to their feats of escape, we see that they are far more intelligent
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than we can define, and this invests me emotionally. These are not cold, slimy, spineless creatures to me. I feel transformed by each experience with them, as if contacted by a fifth dimension, an intelligence previously unknown to me, and one that is quantifiable: they can learn complex tasks, reason through problems, and have been observed engaging in “play behavior” (Kuba et al. 2006). For instance, aquarists have observed octopuses in tanks throwing plastic bottles into water jets and then catching them. At the Monterey Bay Aquarium, I was entranced when the giant pacific octopus reached across her tank to touch the spot where my finger rested on the glass and then traced from her side as I moved my finger along the glass. It is also interesting that they can recognize the faces of both the aquarists they like and the ones they don’t. While at the Monterey Bay Aquarium watching a common octopus, David and I saw firsthand as one changed color and retreated when a keeper she didn’t like appeared in the room.
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My attachment to some of these animals inevitably leads to disillusionment in our quest, as on one day in particular during a long trip to Indonesia. We had looked so hard for octopuses, of any species, on all our dives. After a total of twenty-nine dives in three weeks, I had not seen a single octopus. The reefs and rocky shallows should have been teeming with them, since this is the center of marine biodiversity and the region is home to countless cephalopod species, but we continued to come up short. Since octopus is a valuable source of food and is hunted heavily in Indonesia, it was clear octopus was being overharvested. Indeed, we watched cooler after cooler packed with hundreds of octopuses being shipped from some villages.
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After five more days of looking, I decide to get smart and have the professionals help me. So I ask Jardeen, our divemaster, if he can help me find octopuses somewhere besides our reef dives. Though he doesn’t speak English, I understand that he wants me to come back in an hour and someone will take me to where the octopus are. Now we’re in business, I think, and go off to find a couple of plastic aquaria and nets. When I come back, there’s a fifteen-year-old girl on a moped waiting for me. She smiles and gestures for me to hop on behind. Hmp, I think, this is the octopus hunter? But I trust Jardeen, so I climb on and we zoom off through the coastal forest of Sulawesi. We start on a hard, one-track dirt road, but after about ten minutes it becomes a soft sand trail with overhanging branches that we duck under at high speed. The trail shifts again and becomes a dark, overgrown path that is so roughened by ruts and roots, we have to walk the moped in places. I’m feeling mildly unnerved and wonder where we’re going and what we’ll find when we arrive. We finally emerge from the jungle to a stunning coastline, pristine white sand beach giving way to expansive, healthy seagrass beds rimmed with rocky intertidal and offshore reef. The girl speaks no English, so we splash along in silence, wading through the shallow seagrass toward our rocky intertidal destination. I finally remember a Bahasa phrase to ask her name, “Sieppa nama anda?” She laughs shyly, but I get a surprised look and she answers “Meeta.” “Terrimah kasih, Meeta. Abba kabar?” Thank you Meeta, How are you? She laughs, and answers, “Bik!” Fine! Well, a pathetic showing of all the Bahasa I know, but at least she thought I was funny and probably not dangerous. After about fifteen minutes of crossing the seagrass, we run into a woman harvesting sea cucumbers,
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snails, and urchins from under rocks in the seagrass bed. After a long exchange with Meeta, she joins us to look for octopus. Her method is to look for small dens in overhangs, and then plunge a sharp metal pole into it, presumably to scare or drag the creature out. I don’t like this. After a few minutes of observing, I gesture for her to stop. Right then, another woman comes up excitedly, swinging an octopus from her hand. Apparently, word is out that the bule, the white foreigner, wants octopus. I am crushed. It’s clearly dead. I take the limp animal from her and splay it in a tide pool to gesture that it’s lifeless and I don’t want it. I hold out my aquarium to them, hoping to convey that I want a live, swimming octopus. We start back toward shore, and I feel both guilty and discouraged. Then the same woman comes back, this time with a gorgeous lively octopus, flashing green, brown, and maroon. Happy, I put it in my tank and admire it. It’s indeed vibrant and energetic, just what we need to confirm the species on film. I give the woman some rupiahs, since she had worked hard to help. It’s clear by the stunned and grateful look on her face that I have overpaid her. That’s fine with me; I like that the octopus is worth more alive than dead. It does not escape me that this transaction is a microcosm of all that is bad and good with how we commodify biodiversity. Sustainable harvesting or poaching, they’re simply two sides of the same coin, with the animal always losing. I climb carefully on the back of the moped, balancing my treasure as we bounce back to the hotel. When I return, David isn’t back from his dive. Over the course of the next hour, my lively octopus declines from bright, animated, and vibrant to dull, slow, and unhealthy. It is dying. I look more closely and can see now that the body had been pierced by the huntress’s spear. In some vain attempt to revive it, I release it onto the nearby reef, but I know better than to think it will survive.
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For me, this was the low point in our entire project, the moment when I questioned every part of what we were doing. Coming to a foreign country to film their animals in some misguided idea that we could champion biodiversity conservation—who was I to think we could create a movie that would make any difference? And what in the world was I doing trying to be some kind of Indiana Jones of Indonesian invertebrates? I was no better than the people who killed octopuses; at least they did it for food. I felt I had personally injured this animal. What a mess Indonesia was anyway, from mining to dynamite fishing to massive coastal pollution; it was just going to get worse and there was nothing I could do to stop or slow globalization, blast fishing, and rampant coastal pollution. It was a bad day, and I had lost sight of my deeper intentions in embarking on this venture. When David eventually came back, I couldn’t even talk to him about it. I just sort of mumbled something about having to release an octopus we found. He so clearly knew how badly I felt that he never said anything about it again.
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Cephalopods were once one of the dominant life forms in the world’s oceans. Today we have a smaller diversity of about 800 living species of cephalopods. Our statistics regarding endangerment are very imperfect for this group, but our high-pressure top predators are caving under the stress of over-fishing, habitat destruction, and loss of prey. As I touched on earlier, cephalopods have the particular problem of being what biologists call “semelparous,” which means they only reproduce once in their lives. This is a very risky business. For a mother octopus or squid, it means she could lose it all if she has babies in a bad year or a bad place. Most animals reproduce multiple times and have a better chance
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of creating at least one future generation. One small change helping cephalopods along is the fact that the predatory fish and shark that eat them have been reduced by over-fishing. Sadly, it’s not a win-win. The intricate ecology of place needs all its species intact, even if the loss of one is the short-term gain of another. Maybe over-fishing of their predators is why cephalopods remain abundant enough to support a vibrant fishery in the Mediterranean. Unfortunately, this is not sustainable. Although cephalopods make up only a small proportion of world fish landings (cephalopods make up approximately 3 percent of total fishery landings), there have been substantial increases during the past four decades, and total world harvests of cephalopods reached a peak of over four million tons in 2007 (Rodhouse 2014; FAO 2014). Most of the main species of commercial importance in the northeast Atlantic or the Mediterranean are represented in our Blaschka collection: octopus Octopus vulgaris and Eledone cirrhosa, cuttlefish Sepia officinalis, and squid Loligo forbesi, Loligo vulgaris, Todarodes sagittatus, and Illex coindetii (Sonderblohm et al. 2014; Regueira et al. 2014; Gamito et al. 2015). Making up the largest cephalopod component in 2012 world fisheries are the omastrephid squid, including the Humboldt squid (Dosidicus gigas) and the Japanese flying squid, Todarodes sagittatus (FAO 2014). Stocks of the Argentine shortfin squid Illex argentines are considered overfished. Blaschka match Todarodes sagittatus experienced a fishery collapse. Many other cephalopod fisheries have declined, but they are not well tracked and it’s difficult to separate natural cycles from the impacts of fishing (Rodhouse et al. 2014). Tracking is further complicated by the fact that the animals are short-lived and some squid have a migratory component to their life cycle (Hastie et al. 2009). Few cephalopod stocks are carefully managed, despite
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increasing pressure on them as finfish stocks decline and invertebrate fisheries become more prevalent (Rodhouse et al. 2014). On a positive note, as soft-bodied animals with internal fertilization, this group may well fare better than most in the acidified conditions of the future ocean. Ocean acidification poses a huge threat to successful fertilization because for many animals, the meeting of eggs and sperm takes place in the open waters of the sea. For the argonaut, on the other hand, fertilization is protected, but the female’s paper shell is highly endangered by corrosion because it is already thin and close to its calcification threshold in some waters. There is also speculation that cephalopods such as squid might be particularly affected by increased oceanic carbon dioxide because they require high levels of oxygen in their blood to sustain the energy demand of swimming, and their blood pigment, hemocyanin, is very sensitive to changes in pH. Lower pH levels can impair oxygen supplies in these species; a pH decrease of only 0.25 units can reduce oxygen capacity by about 50 percent (Rosa and Seibel 2008). In the ocean, the only invertebrate groups for which the International Union for Conservation of Nature (IUCN) is attempting to develop estimates of extinction risk are the cephalopods, lobsters, and reef-building corals. As discussed in chapter 8, the conclusion for corals is that one-third are at immediate risk of extinction. But even this hopeful case, where an assessment is under way, does not help us figure out how our Blaschka cephalopods are doing. As indicated in the IUCN Red List of Threatened Species, preliminary studies report that 24 percent of cuttlefish are classed as being of “least concern,” but a staggering 76 percent fall into the category of “data deficient,” meaning we cannot even assess their threat level or know if they have already
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disappeared. There is more information available for squid, with 57 percent classed as “least concern,” although the remaining 43 percent are again classed as “data deficient” (see www.iucnredlist .org). Assessments are ongoing. The conservation status of less than 2.5 percent of the world’s described biodiversity is currently known. Clearly this limits our understanding of the impact of humans on biodiversity, and with it the ability to make informed decisions on conservation planning and action. One of the major challenges for the IUCN Red List is assessing the larger groups in the ocean that represent the majority of the world’s biodiversity. When you think of it, there are only 800 species of cephalopod; we should be able to do better than this in assessing their risk for extinction.
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The night of our last dive in Indonesia, I am only halfheartedly in it. I am filled with self-doubt and fatalism, surrounded by degraded reefs and my own questionable, if well-intentioned, actions. I feel like we’ve just lived through some fable, like the universe is holding up a dark mirror. I don’t like what I see. But I don my gear nonetheless and drop into the dark water off the jetty. As expected, in this somewhat miserable, impacted caricature of a seascape, we come up empty. This is the same place, festooned with fishing line and grounded in garbage, where we earlier found some interesting nudibranchs. As we head back to the boat, however, I catch a slow, small flash of unexpected white out of the corner of my eye and stop for a closer look. What is this two-inch, round, bumbling critter levitating above the bottom? Nothing I have ever seen before, but suddenly I know from the way it hovers that it’s a wondrous find: a cuttlefish as small as a mouse, rather
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casually ambling and bumping around the reef edge, keeping a watchful eye on us. Who knows how long it has been along with us at the edge of our lights? As David swims up with the camera, I gently herd this ambling critter, enchanted by the calm, adorable dwarf levitating between my palms. No attempt to jet—it hovers stoically above my hand, cool dark eyes measuring the level of threat and seemingly finding it low. Our dwarf hovers and maneuvers around like a slowmotion hummingbird. Meanwhile, David is muttering happily as he films, beside himself to have found his favorite critter. This was the priority animal for us, our primary reason to come to Indonesia, since the Blaschkas produced a lot of cephalopods in glass and cuttlefish are among the most endearing, with emotions tattooed in color on their surface. They are not only smart and display elaborate social rituals, but they possess the ability to change into almost any shape or color. After a brief visit and display of colors and textures, the dwarf stumpy-spined cuttlefish rises out of my hands and jets off into the reef. After a tiring, dark dive, our team emerges heartened by the find.
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7. SEA STARS Keystone Species in Glass
THE REEFS OF Nusa Lembongan in Bali are home to some of the
most dangerous currents in the world. Despite the sometimes treacherous down-rushing currents, the region draws scientists and conservationists from around the world because it houses the world’s highest marine biodiversity—including species from all the groups the Blaschkas spun into glass. While the fast currents here make for tough working conditions, they’re nirvana for feather stars, which I was hoping to see as I worked with scientists to survey the health of coral reefs throughout Indonesia. I was also on the hunt for my last group of Blaschka matches: echinoderms. It was early in the trip, and our team was just getting the routine down. Our surveys required six two-person dive teams to identify and count every fish and coral species and evaluate the health of the corals, the living framework of the reef. Even as we dropped down at the beginning of this dive, the current was fast enough that we could not swim against it. Instead, we moved upstream by pulling ourselves hand-over-hand along the ocean floor. We had been warned that we had a narrow window of time in which to work and that the current would pick up at day’s end— which is also the best time to see feather stars. Working in such
The common sea star (Asterias rubens) as a juvenile in glass. This is part of a sequence that the Blaschkas crafted showing the development of a sea star from planktonic larva to this newly settled juvenile. Asterias rubens is a species that was decimated in 2011 in the U.S. Atlantic by the sea star wasting disease. Photo by Guido Motofico, courtesy of the Natural History Museum of Ireland.
high currents is unpredictable, and I was worried most about the safety of my Indonesian colleague Adah, who is obligated to wear her bulky shawls and hijab under all public conditions, even while diving. When I talk about the Blaschka collection as reaching back through time, I mean back over the relatively small 160-year stretch encompassing industrialization, not back 360 million years to the Devonian era. Yet when we look at the glass feather star models, this is what we are seeing: a fossil in glass that dominated the planet millions of years ago. Back then, Devonian-age stalked crinoids called sea lilies stretched to over 100 feet long and carpeted the ocean floor. While I wouldn’t find feather stars that big today, they are no less spectacular in their contemporary form. To easily find living representatives of feather stars, we have come to the Coral Triangle, the center of echinoderm biodiversity. Once we have set our survey lines by laying a thirty-foot measuring tape across the reef, we begin to identify and count corals. These corals, at such a high-current site, look terrific, with bright colors and no encroaching algae or microbial diseases. Under normal conditions, we would have floated above the reef, filling our slates with species lists and health checks, being careful not to touch anything on the bottom. But here we can hardly hold onto nearby rocks to avoid getting pulled away by the current, let alone write on our slates. We persevere until it’s time to reel in our survey lines and drift back with the current. Adah’s hijab billows behind her like a cape. I am relieved that she managed her extra layers so effortlessly along with intensive fish surveys in high currents. As we float with the growing current and fading light, the reef edge spreads before us like an underwater tapestry of reds, blues, oranges, yellows, and greens. I am struck, as always, by the magic that is the biology of the coral reef ecosystem. When healthy, reef
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ecosystems are a brilliant spectacle of life, fueled by the coral’s solar-powered cells. Clown fish dart between anemone tentacles, a mantis shrimp peers from its burrow, bright orange and blue hydrocorals grow, and a barracuda prowls for less cautious reef fish. We move on, zillions of tiny red and yellow fish darting into the branching coral for cover as we pass. Then I glimpse what I hoped most to see: the feather stars as they come out to feed. During much of the day, they hide in the reef or in branches of corals, their long spindly arms curled into a tight ball. As the sunlight fades, they rise up from hiding and make their way to the highest points of the reef, surprisingly mobile for something that looks so rooted and stiff. They unfurl their long, colorful spiked arms the same way a fiddlehead fern unfurls in the spring, except in minutes instead of weeks. Once unfurled, they spread their eight-inch-long arms wide in the current to capture microplankton, creating a multicolored spectacle, each crowding against the other for the highest spot near the greatest current (page 140).
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Collectively, echinoderms are the most iconic and ecologically important of all the marine invertebrates, and the Blaschkas spared no talent in depicting the varied symmetry of this group in watercolor and glass, portraying sea stars, ancient feather stars, brittle stars, and the unassuming sea cucumber, which, though tube shaped, is no less a star. Despite the range in their appearance, these are all echinoderms, a name that means “spiny skin.” Most have fivefold symmetry, whether it is expressed as arms in multiples of five or, in the case of the sea cucumbers, five rows of tube feet running along the wormish body. Echinoderms seem alien
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when you consider the improbability of how they actually function. Anyone who has ever watched a sea star walk, for instance, will know what I mean. While most sea stars have five arms, some, like the sunflower star in the Pacific Northwest, can have from sixteen to twenty-four arms, and each of these arms might have a hundred tiny suckered tube feet underneath, each a quarter of an inch long. A sunflower star is nothing short of spectacular, a lion of the underwater, three or even four feet across and capable of chasing down prey, like scallops, by actually running along the sea floor at a rate of three feet per ten seconds. Before the huge sea star mass mortality in 2013–14, they were as abundant as dandelions in the Washington subtidal. The ones we grow in our tanks at Friday Harbor Labs can even snatch a falling clam in midwater, like my dog catches a ball. To run across the bottom like they do, all 500 to 1,000 tube feet need to grab and release their hold on the sea floor in a perfectly coordinated way. This far exceeds the complexity of how a millipede walks. Each tube foot relies on a hydrostatic skeleton, which is a muscular, fluid-filled cavity, and the creation of suction on the bottom of the tiny foot, which is just wider than a cat’s claw. The grabbing and releasing is somehow orchestrated through a complicated water vascular system with valves and check points, activated by a fairly simple nervous system. If understanding how a sea star walks is complex, consider how some feed. Carnivorous sea stars such as the ochre or sunflower stars evert their entire stomachs onto or into a prey item, such as a clam, use digestive enzymes to turn the body of the animal into a slurry, and then absorb it. But first they have to use their tube feet to open the clam by brute force so they can insert their stomach. While the best-known sea stars are indeed predators, feeding on bivalves, barnacles, worms, snails, and even other stars, their close Feather stars in Indonesia: a crinoid feeding on a reef in Bali (top) and Drew watching a crinoid on a high current wall near Kapota Island. Photos by Drew Harvell (top) and David O. Brown.
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relatives, the sea urchins, are almost exclusively herbivores, eating algae. Some, however, are equal-opportunity omnivores that will happily munch on small crustaceans or sponges that come with the algae. Brittle stars and feather stars are completely different and feed on very small things, using feathery arms to filter plankton from the surrounding water, or hoovering up sand grains coated with organic matter. Sea cucumbers, unlike many of the sea star species, are exclusively nonpredatory and feed either by filtering plankton or by consuming detritus from the mud. However, lurking within even this simple feeding mode are new discoveries, such as the recent one that some sea cucumbers can multitask and feed with both their mouth tentacles and their “respiratory trees,” which are tucked inside their anus (Jaeckle and Strathmann 2013). It’s handy to have a backup for feeding, because when attacked by predators, sea cucumbers eviscerate their entire digestive system as a defense. Ecologically, many cucumber species are ecosystem engineers, as are worms. We see them commonly in both temperate and tropical oceans, deposit-feeding and bioturbating soft sediment communities, which helps oxygenate deeper sediments. Although some sea cucumbers are drab and wormlike, those crafted by the Blaschkas have striking colors and patterns. The Blaschkas depicted a shimmering diversity of both temperate and tropical sea cucumbers in glass. Their Trachythyone is a sparkling wonder of iridescent purple tubercles set in a body of mottled blue (page 143). Contrast this with the smooth brown body and flat feeding tentacles of Synapta fasciata. The length and coils of the sinuous, ciliated arms of the Blaschka brittle stars, in both watercolor and glass, are truly epic. Those glass arms are also very fragile, as evidenced by the pile of brittle star arms belonging to Ophiothrix serrata that we found in one
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echinoderm diversity in glass (clockwise from top left): Mediterranean crinoid Antedon mediterranea; photo courtesy of the Corning Museum of Glass. Brittle star Ophiothrix serrata; photo by Guido Motofico, courtesy of the Natural History Museum of Ireland. Sea cucumber Synapta fasciata, with smooth body and no tube feet; photo by Kent Loeffler. Sea cucumber Trachythyone peruana; photo by Kent Loeffler.
of our dusty boxes at the Corning Museum of Glass’s offsite storage facilities (page 145). A century of being shuffled around had left the needle-thin arms in a clutter of broken sections. This piece has now been restored in preparation for a large 2016 exhibition at the Corning Museum. Brittle stars like Ophiothrix serrata feed by deploying these eight-inch-long ciliated arms high into a
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fast current and catching microscopic phytoplankton on their tiny tube feet. I have seen them on day dives in the Caribbean, tightly wrapped into the reef or entwined in a mesh of sea fans. At night, they perch as high as they can get on the tops of soft coral colonies, or even seagrass blades, to snag passing food. Every brittle star is a gem of long, winding arms and often brilliant, colorful patterning on the central disk. Ecologically, they can be abundant enough to be important as a food source for hungry predators, and we have a high diversity of them in the Pacific Northwest, including the Blaschka match Ophiopholis aculeata (page 145). They are a small but important component of our oceanic biodiversity that is not present on conservation checklists and could slip silently away without being noticed. This is the opposite of the case of their close cousins, the sea stars.
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Of all the echinoderms the Blaschkas shaped into glass, the sea stars are among the most important ecologically. The five-armed sea star, a so-called keystone predator, reigns supreme in tropical and especially temperate marine ecosystems. A keystone species is one that exerts a disproportionate impact on the shape of its community, whether it’s a beaver damming rivers and creating a wetland or a sea star trimming back common mussels to make room for rare species. The term “keystone” was coined back in 1969 by my former postdoctoral adviser Bob Paine, from the University of Washington, in describing the transformative effect of removing ochre stars from shores in the Pacific Northwest. Bob, a distinguished marine ecologist, popularized the use of experiments in piecing together the linkages in natural marine ecosystems. In the 1960s, he hypothesized that the ochre star was master
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Ophiothrix serrata brittle star before (left) and after restoration. Photos by Elizabeth R. Brill (left) and the Corning Museum of Glass. Daisy brittle star (Ophiopholis aculeata) in glass (left) and alive. This is one of the most common brittle stars and is distributed worldwide. We saw this one in Friday Harbor, Washington. Photos by Elizabeth R. Brill (left) and Drew Harvell.
in determining which other animals could live in the intertidal region. In a foreshadowing of what nature is doing on those same shores today, he took all the stars off sections of the rugged rocks of Tatoosh Island on the outer Washington coast. The response was a change in the entire appearance of the intertidal. In the absence of their keystone predator, squirrel-sized mussels outcompeted all other animals and plants and took over space on the rock. A multicolored seascape of diverse sea anemones and sponges and sea squirts was replaced by what looked like a huge glacier of dark mussels spreading upward from the deep. As a graduate student, I was inspired to visit Tatoosh Island with Bob and listen to him brag about his “mussel glacier” and see the shocking difference in the intertidal sites where he had removed the ochre star. What would it look like if most of these keystone star species were removed from our waters? I can tell you firsthand. In the winter of 2013, dead and dying sea stars littered the beaches and tide pools of the Washington coast. I stood on the rocky beach, the glittering lights of the familiar Seattle skyline across Elliott Bay, and took in the carnage that lay before me. The beach, from water’s edge to high up in the rocks, was littered with the arms and twisted bodies of three species of sick stars, including ochre stars. Laura James, Chuck Greene, and I counted over 150 stars on the beach that night, and over half of them were falling off their rocks, losing arms, or had gaping lesions. I had been called to sample the dead stars on this beach by Laura James, an intrepid Seattle diver. She had earlier commented that she was witnessing “the change of her lifetime” as nineteen species of the very rich sea star diversity surrounding Seattle were dying at all her best dive sites. I’d been following the spread of this epidemic since August, but it hadn’t affected the San Juan Islands yet, and it was ominous to see our three dominant species of star melting away within sight
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Healthy populations of the keystone star Pisaster ochraceus eating back the mussel bed in Bamfield, British Columbia. Photo by Drew Harvell.
of Seattle’s lights. Part of the dread was that the syndrome, known as “sea star wasting,” had been thought to affect only a single species and only during the warm months. Now we were seeing it in colder winter waters. This was a new and unsettling development, and we had no idea what was killing the sea stars; it was either a new, undescribed infection, a further decline in the ocean’s pH, or even something else.
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At the time of this writing in 2015, at least twenty species of sea stars from Alaska to Mexico are still experiencing mortality, disappearing in piles of spicules and detached arms. It begins with the star looking a bit flattened and deflated, then lesions appear on their arms, and then suddenly an arm walks away and organs spill out. By 2014, sea stars had become rare in places they were once abundant and iconic, from California all the way up to Washington State. Our Alki Beach observation in December 2013 was important because it occurred in cold water, and stars on other cold beaches stayed healthy. Many other star populations in Washington and Oregon did not decline until the summer warming hit, fully six months later. The epidemic had actually started a year earlier on the East Coast, where it devastated populations of the Blaschka match common sea star, Asterias rubens (page 136). Laura was surprised to see over a hundred stars still alive on that beach, since on dives to the subtidal waters below, she had recorded thousands dying. She showed us video footage of them falling off the pilings into huge piles of spicules. This same footage, coupled with environmental reporter Katie Campbell’s compelling story for CNN, would in 2015 win them a shared Emmy Award for environmental reporting. That night at Alki Beach, half the ochre and mottled stars fell apart, leaving the beach littered with still-moving arms. The other half died in the following two weeks, leaving a body count of over two thousand dead stars at the one site. This mass mortality continued into January at certain sites around Puget Sound, including Alki Beach, Tacoma beaches, and Mukilteo. Adding to the mystery, stars in the nearby San Juan Islands remained healthy through March (Eisenlord et al., in review). However, by the end of summer 2014, our stars in the San Juans had also suffered a massive hit, and we had solved one big
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mystery—the cause of the epidemic. It turned out to be a killer virus. After three months of detailed molecular work sifting through thousands of bacterial and viral genetic sequences, Ian Hewson from Cornell identified a candidate virus. Further experimentation by Colleen Burge and Morgan Eisenlord, also working in my lab at Cornell, confirmed it. They injected fifteen healthy sunflower sea stars with a slurry of virus-sized particles from sick ones. All became sick and died, while the controls remained healthy (Hewson et al. 2014). Here was the sad evidence that one of our most important ecological keystone species was taken down by the smallest of infectious agents, a virus. It also represented a new and foreboding discovery about the triggers of ecosystem collapse. This is the largest disease epidemic of unfarmed species ever seen in the oceans, and it has, for now, robbed our shores of once bright sea star biodiversity. The populations of over twenty species have been decimated, including those of the iconic purple, orange, and pink gem-like ochre stars that grace half the T-shirts sold in the San Juan Islands and that are beloved of every child who plays on those beaches. As of 2015, ochre stars are completely gone from many California shores and are rare on Washington shores. The giant sunflower star (Pycnopodia helianthoides), once as common underwater as starlings are in the air, is completely missing from our deeper subtidal waters. Disease, under the ocean as well as on land, is one of the silent thieves of biodiversity. This epidemic was well studied because it spilled into the intertidal and was seen by many people. Will the ochre star and the other nineteen species affected recover? It depends on whether the new baby stars recruited to our shores in the fall survive the next season. It depends on whether stars evolve resistance to this new killing virus. It depends on whether the levels of ocean acidification increase and interfere
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with the successful free-spawning of the few surviving stars. Sea stars are in the group that has been identified as vulnerable to increasing levels of acidification, both because they free-spawn in the ocean, exposing the critical fertilization process to pH stress, and also because the developing larvae have fragile skeletons dissolved by corrosive waters. The eventual recovery of the sea stars also depends on how far north the killing epidemic spreads, since Alaska is the last refuge for these endemic stars. All we can do now is wait for the answers in the next warm season. Infectious diseases are silent killers that stalk our oceans unseen. As with human diseases, the probability of a wildlife outbreak depends on the relationships among the pathogenic microorganism, the host, and the environment. A change in any one of the three can trigger an outbreak. We are still trying to understand the role of changes in the environment, like warming oceans and coastal pollution, for the sea star epidemic. We do know of other cases where underwater biodiversity has taken a big hit from disease that was aided by warming waters. Two species of Caribbean coral and two species of California abalone have been driven onto the endangered species list by disease (Burge et al. 2014), coupled with warming waters. In 2014 alone, twenty species of coral were added to the endangered species list (Keller 2014), nudged to endangerment by losses from disease. Large mammals such as dolphins, seals, and sea lions have suffered catastrophic losses in multiple large epidemics as well (Burge et al. 2014). It’s also worth remembering that on land, the chytrid fungus of frogs and salamanders has already driven perhaps a hundred species to extinction (Crawford et al. 2010). Infectious diseases have the same potential to drive species to extinction in the oceans; it’s just vastly harder to detect these events. The unusual susceptibility of some echinoderm and coral groups to disease is a sentinel, like the canary in
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the coal mine, warning us to take heed of looming danger. How many other, less iconic or less visible underwater species have already been silently stolen by disease? Certainly, no one is watching the health of feather stars or brittle stars in the high-current waters of Bali.
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As we are carried fast now with the current in the growing dark, we see that the feather stars aren’t the only echinoderms that creep from the safety of the reef. Brittle stars are a favorite food for fish and spend their days hidden under corals or rocks or tightly furled in the branches of soft corals. As daylight wanes, the long-armed brittle stars also wind their way to the highest points and reach stiff, filtering arms into the current. Sea cucumbers are easier to miss, but one barrel sponge we pass is covered with tiny, apodous Synapta lamperti. “Apodous” means without feet; this family of sea cucumbers does not have tube feet. The Blaschkas re-created nine different species in the Synapta genus alone. On the reef edge, I spot a huge foot-long black-spotted cucumber, slowly dredging through the sediment one tentacled arm at a time. It’s striking, with its spots and large, jet-black arms, but what I really want to see is the juvenile of this species, because the youngster has orange spots on a mottled black and white background; it’s a dead ringer for an unusually colored species of toxic, brightly colored nudibranch. This is a spectacular example of using the warning coloration of the nudibranch for its own protection, exactly like the Batesian mimicry of butterflies, played out across whole phyla of invertebrates. After the trauma of our recent star outbreak, I am happy to reflect on this display of echinoderm biodiversity, out to greet the advancing dark.
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8. THE VOYAGE OF OUR
BLASCHKA BIODIVERSITY
THE UNDERWATER CLIFF FACE loomed beside me as I struggled to
catch up to the other divers. I had stopped in mid-breath when I saw the hamster-sized brown-spotted nudibranch Discodoris atromaculata, popularly known as the sea cow. A somewhat undignified name for a predatory mollusk, but the big brown and white blotches are definitely Guernsey-like. I am alone now, way behind the group, but it is oddly pleasant having the seascape all to myself. We are two-thirds of the way through our dive in the marine reserve at Portofino, Italy, and I’m happy, having been lucky enough to find four species of nudibranchs, including a tiny zebra slug, small as a yellow jacket wasp, glittering bright blue with yellow stripes (page 154). The current zooms me along, and sixty feet ahead I see a cliff edge carpeted with bright purple and gold sea whips and colonies of red precious coral, Corallium rubrum. It’s a happy place, a protected corner of the ocean, with zooming big fish, foundation species like the sea whips and corals, and bright gems of biodiversity like the nudibranchs. I have shared a global voyage of discovery with the Blaschkas, exploring the tree of invertebrate life, following the trail of these soft-bodied creatures from the coast of Washington to the heart of the Indo-Pacific, with several stops in between. The most satisfying The Mediterranean coral Dendrophyllia ramea in glass. This is a nonphotosynthesizing coral endangered by warming-related mass mortality in the Mediterranean. Photo by Guido Motofico, courtesy of the Natural History Museum of Ireland.
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a zebra slug ( Felimare picta) on an underwater cliff in the Mediterranean. Photo by david o. Brown.
news is that I have observed Blaschka matches at all these sites, but especially in the Mediterranean. We find them in every habitat we explore. Along the Ligurian coast, there were rafts of by-the-wind sailors washed up on the beaches, and we were surrounded by flotillas of the mauve stinger jellyfish during one dive. The fish markets were packed with cephalopod matches, probably as they were during the Blaschkas’ time: the common octopus, the curly tentacle octopus, the bobtail squid, and the common cuttlefish. Two species of the tiny sepiolid squid turned up on our dinner plates. Underneath the docks and attached to wrecks are nudibranchs, anemones, bright feather duster worms, brittle stars, octopuses, and cuttlefish. Inside the no-fishing preserve at Portofino, the sheer rock walls are carpeted with sea whips, precious corals, sponges, and sea squirts. Predatory nudibranchs and red sea stars prowl
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these same rock walls. Having seen them previously as Blaschka glass masterpieces, I find their natural splendor elevated by translation into art forms. We still have within our reach the fragile legacy of the Blaschkas. Although it is clear from the mastery of their glass pieces that Leopold and Rudolf loved the natural world to the point of obsession, I enjoy hearing it in Rudolf ’s own words. Rudolf writes in a letter to an American colleague, Walter Deane (a founding member of the New England Botanical Club), “I think I belong to that same order of men as you, to the true lovers of nature. On every walk I take, there must be something to study of nature, it may be a plant or insect or bird or whatever. I think a man can never finish these studies and is never too old to learn from nature” (Rossi-Wilcox and Whitehouse 2007). In another letter, to Mary Ware at Harvard in 1908, Rudolf reflects back on his time making and observing sea creatures in his aquarium: “In thinking of Marine Zoology I am getting quite young again, so much is this science amalgamated with my own development. I remember of the time of 28 years ago when we had established for our studies an Aquarium-room filled with seawater-tanks, and of the eagerness and pleasure in observing the life of the wonderful delicate beings from the sea” (Reiling 2007). When Leopold and Rudolf Blaschka crafted their first marine masterpieces in 1863, the oceans were healthy and sea animals plentiful. There were six billion fewer humans alive, and the planet still held many wild places yet to be discovered—and exploited— by man. The combustion engine was still in its nascent stages, having been created in 1859, and the first fuel-powered automobile was still two decades away. The Wright brothers wouldn’t launch the world’s first airplane for another forty years. People communicated by telegraph and only a few owned personal radio sets. Much has changed since then.
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It would have been impossible for the Blaschkas to comprehend the world of today. They never could have imagined that the world’s population would surpass seven billion, nor could they have imagined the technological achievements of our era, from autos to iPhones. Certainly, they might have begun to see the early signs of industrial pollution, but it’s unlikely that they could have imagined the eventual toll it would take on their beloved ocean environment: first acid rain and then the wholesale change in the global ocean’s pH, creating a hot acid soup that dissolves the very skeletons of its lifeblood. To the Blaschkas, the ocean was a vast, immeasurable realm, not even fully charted and abundant with magical creatures that most of the world had no idea existed— which is what inspired them to spin these glass creatures in the first place. What would they make of today’s despoiled oceans— the millions of tons of plastic waste floating in endless gyres, bigger even than small countries; dead zones that span full hundreds of miles in once species-rich regions; the precious corals and tide pools evoked by Gosse bleached out and dead? It would be the stuff of nightmares, to be sure. In writing this book, I occasionally imagine myself sitting, especially with Leopold, and explaining all that has happened and how it affects the ocean biodiversity he loved so much. This is what I would say. I share with you a passion for the artistry of the ocean’s diverse invertebrates. It is painful to describe how, in our quest for improved life and material goods, humans have squandered the riches of our planet, including the ocean. Some of the 800 invertebrates you have created to teach my students are at risk in today’s oceans. In the past 160 years, the world’s population has grown from one to seven billion and over-fishing, coastal pollution, and habitat destruction have taken a big toll on the diversity of all marine animals. We still have lots of jellyfish, anemones,
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nudibranchs, and even some cephalopods in our oceans, but we cannot easily find as many different kinds as you had at your fingertips. It turns out to be surprisingly hard to track the fate of the many animals you saw so easily. You could have gone to the shore at Naples and found twenty species of nudibranchs and five species of octopus in a single day. Even with equipment to breathe underwater, our team spent nearly a week diving in Spain and Italy and found only six species of nudibranchs, a single octopus, and a single cuttlefish. If you had dived in the night ocean at Naples in 1868, you might have seen an ocean alive with five times as many squid, octopus, and cuttlefish species as today. If you were stationed beside a tide pool, perhaps fifteen anemone species would be at hand. I’m sorry to tell you that industrialization has filled our skies and oceans with a gaseous pollutant, carbon dioxide, which is changing our climate and rapidly warming the entire planet. The oceans are doing their job of absorbing almost 30 percent of the pollutant, but in so doing they have become 30 percent more acidic globally. Some spots are already so acidic that sea butterflies and oysters are dissolving and the fertilization of new eggs fails. Perhaps the worst of the news is that messing with the atmosphere on this planetary scale has set a change in motion that will continue for fifty years even if we reduce the emissions today. Climate change, which has caused all the world’s oceans to warm, is taking a huge and continuing toll on your brilliant undersea beds of precious corals, soft corals, and sponges. The impact that warming and rising seas will have on humans living near the sea in countries like Indonesia is too sad to even tell you about. No matter how I describe the changes of the last 160 years to Leopold, it sounds more like science fiction than fact. We are living near a vastly different ocean that puts our living biodiversity at risk.
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Although our data are poor, what undeniable changes have we seen in the species that were common in Leopold and Rudolf ’s day and that are part of our collection? The Blaschkas selected many invertebrates that were easy to collect, abundant, and found throughout the world, but a full 25 percent of them are not widespread; they are endemic to the Mediterranean and found nowhere else on the planet. Some of these species are among the rare or unconfirmed on my list. Although we found healthy ones in northern Italy, the gorgeous orange cup coral, Astroides calycularis, is an endemic species and is listed as endangered in the Mediterranean. The solitary cup coral, Balanophyllia europaea, has been endangered by repeated warming events in the north Adriatic, with over 80 percent killed at some sites in the 2012 warming (Kruži´ c and Popijaˇc 2015). I also had hoped the different octopus and squid species would be more common. I’m concerned about the jeweled squid and the paper nautilus. The paper nautilus, Argonauta argo, lives in tropical and subtropical seas, including the Mediterranean, and is reported to be susceptible to mass mortalities in California, these being possibly associated with red tides (caused by toxic algae called dinoflagellates). Interestingly, the baby nautilus, in its early life, resides in salps and some jellyfish and so is reliant on their populations being healthy (Orenstein and Wood n.d.). Chiroteuthis veranyi, the long-tentacled squid, and Histioteuthis bonnellii, the jeweled umbrella squid, are present in deep Pacific waters off Monterey, California, but rarely seen directly by cephalopod expert Maurizio Wurtz (University of Genova) in the Mediterranean. He knows they are still present because both turn up as prey in the stomachs of dolphins and sharks. Although it was always possible to find a nudibranch or two, there were many we could not find, and many were quite rare.
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In the Mediterranean today, important foundation species that create habitat, many of them Blaschka matches, are at risk. Matches at risk include the precious coral (Corallium rubrum), sea whip (Eunicella verrucosa), solitary coral (Balanophyllia europaea), endemic cup coral (Astroides calycularis), and sponge (Axinella sp.). They continue to be heavily impacted in the series of mass mortalities that has rocked Mediterranean biodiversity (Garrabou et al. 2009). Perhaps the most well-studied impacts have been recorded for the precious red coral, since it has been commercially harvested since the Blaschkas created their models in the 1860s. A recent study around the Bay of Naples, using remote operated vehicles to resurvey many of the historical red coral banks, shows huge declines relative to historical surveys from a hundred years ago, even in very deep waters (Bavestrello et al. 2014). This series of shallow- and deeper-water mass mortalities in the Mediterranean, the seat of Blaschka biodiversity, alerts us to climate-linked impacts on ocean life. A 2014 study confirmed that warming events that started in 1983 and have increased in frequency have caused large-scale mass mortality of Mediterranean invertebrates (Rivetti et al. 2014), largely affecting precious and gorgonian corals and sponges, with fourteen events recorded between 1983 and 2011. In some years, over a third of the biomass of habitat-forming species died. A look at the species affected shows there are quite a few Blaschka animals in this group. No one has even tried to detect the impact of these mortality events on the mobile animals such as the cephalopods, worms, and nudibranchs. These animals are also likely diminished in these events through direct heat stress, new outbreaks of disease, and loss of habitat or prey. As discussed in chapter 6, when we look up the twenty-five currently accepted species of cephalopods in Cornell’s collection in the IUCN checklist, eleven are not assessed, six are classified as “data deficient,” and the remaining eight are considered of “least
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concern.” That tells us nothing except that we do not have good numbers. So I cannot say yet how many of our Blaschka animals are endangered or even extinct. We do know that a few are considered endangered and that Mediterranean biodiversity has been seriously impacted in the past two decades. Our invertebrates are not the only animals at risk. The Mediterranean is considered a world hot spot of marine biodiversity, with over 17,000 reported marine species, a fifth of which are found nowhere else (Coll et al. 2010). However, Mediterranean marine life is among the most endangered in the world, due to increasing human threats that affect all levels of biodiversity (Costello et al. 2010; Coll et al. 2012), severe impacts from climate change, and biological invasions ( Katsanevakis et al. 2014). We know far more about the fate of our backboned ocean biodiversity than we do about the fate of invertebrates. For instance, the IUCN reports that over 40 percent of Mediterranean fish are endangered, including popular commercial fish such as bluefin tuna, sea bass, and hake (www.iucnredlist.org). The IUCN cites overfishing, marine habitat degradation, and pollution as the drivers, all stresses that impact our Blaschka matches as well. IUCN records indicate that almost half the species of Mediterranean sharks and rays and over half the species of Mediterranean dolphins and whales are threatened with extinction, as are a third of all crabs and crayfish. What is the prospect for our oceans? We have just passed 400 parts per million (ppm) of carbon dioxide in our atmosphere. It was 280 ppm in 1860, while the Blaschkas were creating our collection. In 2000, it was 370. This huge change in CO2 has contributed to significant climate warming, which is already endangering all the world’s coral reefs and the non-reef corals of the Mediterranean. We are also experiencing a more than 30 percent
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increase in the acidity of our oceans. In considering what levels of CO2 are dangerous for invertebrate biodiversity, I have my eye on 500 ppm because it is a tipping point for the ability of animals like snails and corals and brittle stars to make their skeletons. Big change happens quickly once you pass that point. At what point will our calcified animals not make skeletons? At what point will reproduction and fertilization be impaired for our ocean biota? Our job as scientists is to go and find out. Israeli researchers grew corals at different levels of CO2 and found that above 700 ppm CO2, they grow as small, disconnected anemones and do not calcify into reefs (Fine and Tchernov 2007). The complete failure to calcify is an extreme tipping point. Long before this is reached, we expect to see many calcified animals with thinning skeletons, such as the almost transparent limpets observed in the high-CO2 seeps near Naples, Italy. This is already happening. Even though we know that there will be variation among species in their sensitivity to changing levels of CO2, we can be confident that waters in excess of 500 ppm CO2 will present big problems for many animals with calcareous skeletons. Despite not having enough survey data on our Blaschka invertebrate biodiversity, we do have warning signs. In spring 2014, sea butterflies made headlines and were shown on the cover of Science magazine along with the news that they were actively dissolving in the oceans off Washington State (Bednaršek et al. 2014). The 2013 report from the Intergovernmental Panel on Climate Change, which is comprised of the world’s leading climate scientists, put it this way: Human influence has been detected in warming of the atmosphere and the ocean, in changes in the global water cycle, in reductions in snow and ice, in global mean sea level rise, and in changes in
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some climate extremes. . . . It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century. . . . The consistency of these observations demonstrates that the pH of surface waters has decreased as a result of ocean uptake of anthropogenic [human-caused] CO2 from the atmosphere. (IPCC 2013)
Once the pH shifts to the point that a species cannot reproduce, as discussed in chapter 7, it’s merely a matter of time until it goes extinct. It is sobering to imagine that many sea animals may experience halved reproductive success in the next fifty years; the results would be catastrophic. We know that successful fertilization of sperm and egg is very pH dependent. We know that many invertebrates and fish in the ocean free-spawn; that means they release their eggs and sperm into the ocean water and rely on the correct acidity to facilitate fertilization. Experiments with sea urchins (Stronglylocentrotus nudus) have shown that fertilization success decreased to 45 percent even at 450 parts per million of carbon dioxide (Sung et al. 2014). Other studies confirm that an increase in CO2 can cause pH to drop and reduce fertilization success. Jon Havenhand (2008) has shown that at a pH of 7.7, 24 percent fewer eggs of urchins were successfully fertilized, because sperm stop swimming and do poorly in low-pH water. Another impact of a changing ocean is the spread of diseases that normally wouldn’t survive in cooler waters. Until recently, this kind of emerging catastrophic epidemic was documented best with terrestrial species, primarily amphibians. Over the past two decades, more than one hundred species from around the world have been extirpated by a commonly occurring fungus that was once non-lethal (Pounds et al. 2006). However, as conditions changed, this fungus morphed into a deadly parasite, leaving rain
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forest rivers and High Sierra lakes filled with the fungus-ridden bodies of dead frogs. Scientists watched whole populations disappear overnight (Crawford et al. 2010). We are also now seeing entire marine species diminished by pathogenic microbes. As I discussed in chapter 7, we are currently living through the sad story of a mass viral epidemic decimating over twenty species of West Coast sea star, stretching from Alaska to Mexico (Hewson et al. 2014). Although we’re still working out the full story of what triggered this massive sea star epidemic, all evidence points to elevated temperatures and other stressors increasing the susceptibility of sea stars to a viral disease (Eisenlord et al., in review). It is fair to conclude that the industrialization driven by fossil fuels is the root of most of the evils plaguing our ocean biodiversity. First, it has fueled the massive industrialized fishing fleets that have decimated fish populations on our coastlines and scoured the furthest reaches of our oceans (Ponti et al. 2014; McCauley et al. 2014). Second, it has put greenhouse gases into both the oceans and the atmosphere. Both over-fishing and carbon pollution seem like huge, insoluble problems that have no borders. They are not. For species ranging from East Coast cod to sharks in Hawaii and Asia, new fisheries policies are rapidly preventing a spiral into extinction. This year nine U.S. states passed new laws outlawing the finning and even possession of any shark products. We hope the rest of the world will follow. In contrast to most of my publications, there is only one graph in this book (page 165). It depicts the projected future scenario of CO2 emissions and shows quite clearly the problem we have with inertia. RCP 8.5 is the trajectory we are currently on, and it will lead without question to massive ocean extinctions in the next fifty years, as well as untold human misery due to increased storms,
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rising sea levels, and increased sickness. RCP 2.6 represents one plot of hope, the chance to avert the worst of the catastrophe if we act immediately. Even under this hopelessly optimistic scenario, it would still take until 2050 to begin to dial back emissions levels. Under any of these scenarios, we face big impacts in the next fifty years.
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Fixing the carbon dioxide problem is tricky because it requires such a large and concerted global effort and its effects are played out over long time spans that are hard for us to grasp given the average human life expectancy. Most of my college students were born in the years 1992–1996 and will be over sixty before CO2 levels would begin to drop under the most ambitious, optimistic projections. If we think outside the box, we might be able to do better. We have reached the point where we need not only to reduce our emissions, but also to reduce existing carbon dioxide levels. There is interest now in carbon-reduction methods such as bioenergy with carbon capture and storage. One of the possible solutions for renewable, non-carbon-based energy comes from the oceans. Consider the miracle of biofuels from solar-powered marine algae that require no freshwater and, if their use is properly designed, can also capture carbon and remove it from the atmosphere (Greene et al. 2010). I consider the hopefulness of human ingenuity as I explore the vivid tapestry of soft and precious corals carpeting the underwater cliffside in Liguria, still unmolested by these so-called wicked problems. This entire dive in the marine preserve tucked at the top of the Italian boot has been a fairyland of Mediterranean biodiversity, including bountiful fish, from tiny, sparkling plankton-eaters to
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Emission rate (GtC/y)
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Twenty-first century emission rate trajectories 2025
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Carbon dioxide concentration (ppm)
Year 1,000 800 600 400
Twenty-first century 200 2000
atmospheric CO2 trajectories 2025
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Mean global temperature (degrees C)
Year 5 4 3 2
Twenty-first century
1 0 2000
mean global temperature trajectories 2025
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Projected effects of four different emission reduction scenarios on atmospheric CO2 concentration and mean global temperature. The scenarios, calculated in 2010, show business as usual (BAU), in which the emission rate rises so that by 2100 it increases 500 percent relative to the 2005 rate; aggressive reduction (AR), in which the emission rate begins to decline in 2015 and reaches 20 percent of the 2005 rate in 2050; very aggressive reduction (VAR), in which the emission rate begins to decline in 2015 and reaches zero in 2050; and impossibly aggressive reduction (IAR), in which the emission rate drops to zero immediately. This last scenario is the only one that keeps temperature increases below 2°C up to 2100. (Adapted with permission from Greene et al., 2010)
huge, looming groupers. Although our ocean biodiversity is as fragile a legacy as our Blaschka glass, this place reminds me there is so much we can do to chart a more positive future. I can feel Leopold nodding gravely in satisfaction at seeing how his stunning glass has persisted through times of neglect to emerge as an inspiration to protect the sea animals he loved. I hope we will act to preserve the staggering ocean biodiversity still on our planet.
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ACKNOWLEDGM ENTS
THIS IS MY first book, and it did take a village of wonderful people
to help make it a reality. The book was inspired by my continued wonder at the Blaschka masterpieces and the adventure of finding the living matches. The best gift is the continuing collaboration with David Brown, both through the writing of this book and through his Fragile Legacy film project, as well as in the epic quest that the Blaschkas have sent us on. I also owe great thanks to Jeff Del Viscio, who embraced the early days of our quest and collaborated in producing a rather stunning New York Times animated piece. My son, Nathan, and daughter, Morgan, patiently read early chapters and advised how to make them more readable. From the outset, Morgan pushed me to share my story rather than catalogue scientific findings and facts. Nathan scrawled “show, don’t tell” all over my early drafts and reminded me repeatedly that chapters needed to build toward some kind of payoff for the reader. Merrik Bush-Pirkle at the University of California Press helped with almost every word and showed me how to set up what payoffs there were. Merrik’s steady patience, creativity, and deep insight about good writing structure have been huge gifts in this process. I am grateful also to Blake Edgar for his consistent help and enthusiasm, and to Claudia Smelser for her magic in crafting
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composite figures. Reyn Yoshioka, Cornell honors student turned lab coordinator and book assistant, helped with every chapter, did a lot of fact-checking, and contributed some amazing photographs. Reyn’s attention to detail and passion for the project were epic. He patiently checked and found new references, triple-checked and updated species names, and emailed the second he found a new Blaschka match. I am grateful to the Corning Museum of Glass for our long partnership, beginning with its safe storage of our collection, and to Jim Galbraith in the Rakow Research Library for graciously sharing images of the watercolors. I look forward to our shared endeavor to display Cornell’s collection of Blaschka pieces at the Corning Museum. Warm thanks to Karel Wight, Audrey Whitty, Warren Bunn, Lori Fuller, and Marv Bolt. Cornell’s Atkinson Center for a Sustainable Future (ACSF) and the Corning Foundation provided funds for the film Fragile Legacy, thus helping to defray the costs of our research trips. I am grateful to ACSF director Frank DiSalvo and to Lauren Chambliss for their enthusiasm and help. I am grateful to Paul Feeny for his initial impulse to launch our Blaschka project, and to him and Mary Berens for financial help with our collection. I thank Susan Syversen for her help in restoring our common octopus and several other models. I thank all our donors for their contributions toward restoring our collection and Elizabeth Brill for her brilliant work with our models. The other members of my village are fellow scientists who filled in correct details of taxonomy and ecology. Jim Morin offered his systematic and invertebrate expertise and helped in the initial effort to update to the current names. A wonderful group of colleagues read early versions of chapters: Sara Lindsey, Rachel Merz, and Sarah Woodin helped with worms, Claudia Mills with jellyfish, Morgan Mouchka and Megan Dethier with anemones,
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Richard Strathmann and Morgan Eisenlord with echinoderms, Brian Penny with nudibranchs. Charles Greene helped with the concluding chapter. Allison Tracy commented on several chapters but helped most (in the eleventh hour!) with the concluding chapter and the appendix. John Pearse and Peter Sale read the entire book and contributed enthusiasm and many helpful suggestions. Thanks to Harry Greene for being my “book buddy” and encouraging and advising me about early stages of the writing and publishing process, and to Thor Hansen for advice along the way. Finally, I thank my husband, Charles Greene, for so many discussions about themes in this book, for pitching in to read chapters when I really needed help, and for giving me Haeckel’s Art Forms in Nature—but most of all, for patiently encouraging my two-year obsession with writing this book.
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Polychaetes
Octopuses
Squid
Echiurans Gastropods
Platyhelminthes Ascidians Nemerteans
Sea cucumbers
Brittle stars
Priapulids Larvaceans
Hydrozoans
Scyphomedusae
Anthozoans Ctenophores
APPENDIX A Primer on the Blaschka Tree of Life
THE OCEAN IS the cradle of life, housing the greatest diversity of
living organisms on the planet. When I look at the sea, I imagine it roiling underneath with all the invertebrates, fish, and whales that occupied it hundreds of years ago. It would look just like one of the Philip Henry Gosse prints of tide pools packed with all colors, shapes, and sizes of sea anemones, or one of Ray Troll’s ocean fish prints (www.trollart.com). In this appendix, I introduce relationships in the ocean’s tree of life, the backstory that will link my larger quest to find our star actors. Who was that first, most ancient of invertebrates, and who is its closest relative? Do we humans have any relatives among the Blaschka masterpieces? What are sea slugs anyway, and what is the link within the molluscs between sea slugs and octopuses? Our Blaschka collection is made for telling this story, since we have representatives from most of the branches on this animal tree of life, and some pretty amazing detail on the twigs. It’s possible that when I say “tree of life” you imagine a tree dominated by zebras, lions, gazelles, humans, and turtles. Wonderful though those animals are, they are only twigs on one very small branch, the Vertebrata (meaning animals with backbones), that sits very far from the base of the tree. Being very far from the base means having evolved relatively recently in evolutionary time.
The tree of spineless life, rendered in Blaschka glass.
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It’s the base of the tree and the lower branches that count the most in showing us ancient body plans. The tree’s base is dominated by our spineless wonders, all the animals without backbones that reveal the time-tested forms of life. This is where all the evolutionary action was, and maybe still is. In our introductory evolutionary biology course at Cornell University, our complete tree of life includes all life on the planet, from viruses and bacteria to bigger things called eukaryotes, which are plants and animals with a membrane around the nucleus in each cell. On that complete tree of life, all animals—from sponges to humans—are only one branch amid twenty-six. For this book, I’ve zoomed in on the base of this animal branch. If you look on the internet, you will see many trees of life, some of which are quite complicated and don’t look anything like trees. I’m telling a simpler story in this book, but it is correct and up to date in its details. Like a living tree, our reconstruction of animal relationships is constantly changing as we continue to discover new life and redraw taxonomic relationships as new information emerges. A Sea of Glass sculpts, with the Blaschkas, a tree of spineless life. This to me is the most beautiful of all art—the epic picture of our animal biodiversity, the most ancient of all roots. For hundreds of years, scientists have puzzled over the relationships shown in the illustration on page 170, assembling and reassembling the lineages in the tree. What was the first animal? What is the most ancient body plan? Who branched from that first one and when? How do they all fit together? What is the pattern of extinction and subsequent diversification through the history of time? Can we find all the pieces to solve this puzzle before the increasing pace of extinction, which has finally reached the oceans, overwhelms us?
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Scientists divide the tree of life into large groups, or phyla, of related animals or plants. Each phylum is distinguished by some uniformity of body plan. For example, within the phylum Echinodermata, all animals have fivefold symmetry, showing up as five arms on the sea star and brittle star and five rows of tiny tube feet on the sea cucumber. Echinoderms are also united by deep, shared secrets in their embryonic development, and this links them even to our human phylum, Chordata. This primer shows the larger branches on the tree of spineless life, the phyla, and how the subdivisions, the classes, fit within them. For exam ple, sea cucumbers, sea stars, brittle stars, and sea feathers are all classes within the phylum Echinodermata. Similarly, cephalopods and gastropods are classes within the phylum Mollusca. Cornell’s Blaschka collection has approximately 569 glass invertebrate models, which makes it the largest Blaschka animal collection in the world. The Blaschkas focused the most effort in showing the diversity within two phyla: more than 440 models are either a cni darian (227) or a mollusc (214). These include the anemones and relatives (130 sculptures), the sea jellies and relatives (71 sculp tures), the sea slugs (137 sculptures), and the octopuses and cuttle fish (38 sculptures). But the Blaschkas’ reach embraces more than the cnidarians and molluscs and spans much of the spineless tree of life, including approximately 22 annelid worms, 45 echino derms, 25 chordates, and a dozen animals from other minor taxa. If there are a few branches missing from our Cornell collection, we can fill them in from the 800 different glass animals the Blaschkas made that are scattered around the world in other collections. It is also enlightening to consider some of the very interesting gaps and missing branches in the Blaschka collection, since their omis sion also tells a story.
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The Blaschkas drew from many of the branches for their glass models, although the focus of their effort was to depict softbodied animals, such as jellyfish, anemones, sea slugs, octopuses, and worms. The Blaschkas wanted to create, in glass, those spineless animals that could not be easily seen by people. For example, a crab is hard bodied and can be easily preserved, but an octopus or jellyfish loses its distinctive shape and color when it dies, and it can’t be stuffed like a mountain lion or badger. But I am getting ahead of myself; let’s start at the beginning. Which animal is the most ancient, and do we have a model to show it? SPONGES
Sponges, the phylum Porifera, have long been considered by many biologists to be the most ancient of animals. They are distinguished by special cells called choanocytes that are both pumps that move water and food filters deep in the chambers of a sponge. They are a trick of nature, instrumental in an animal that works well with no tissues or organs and only a collection of cells. Biologists view sponges as the key to understanding how tiny, unicellular organisms propelled by thread-like flagellae aggregated to form the first multicellular animal, which might have looked like a sponge. We no longer have a single sponge in our collection, but the collections at the Natural History Museum of Ireland, in Dublin, and the Museum of Comparative Zoology at Harvard University have models of a Mediterranean sponge. CTENOPHORES
With the advent of DNA sequencing, the relationships in the tree of life are constantly being rewritten, so even the most basic question, “Which is the first branch?” is not settled. For instance, until recently, scientists like myself believed that sponges were the
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Ctenophora: Hormiphora plumosa in glass. photo by Kent Loeffler.
most basal branch of animals. However, a groundbreaking study first published in 2013 (Ryan et al. 2013; Moroz et al. 2014) nudges sponges aside. The prize of earliest branch in the tree of life now goes to the comb jellies, in the phylum Ctenophora. Comb jellies are distinguished by having a special adhesive cell called a colloblast, used to capture tiny plankton, and rows (or combs, hence their name) of iridescent cilia for propulsion. It is exciting that its ancestry as one of the oldest animals was confirmed in 2012 in work done at our own Friday Harbor Laboratories in the San Juan Islands. John Finnerty, professor of biology at Boston University, comments on the implications: “If the split between ctenophores and all other animals was the earliest split in animal evolution, it suggests some unintuitive facts about evolution. . . . For example, that sponges, which are very simple animals that lack a nervous system and lack muscle cells, actually came from an ancestor (the ctenophores) that had those features” (Williams 2013). The Friday Harbor team made its discovery by extracting DNA from ctenophore embryos, sequencing the entire genome, and comparing it with whole genome sequences of twelve species from other animal phyla. Billie Swalla, director of Friday Harbor Labs, says, “We feel pretty confident that ctenophores are the sister group to the rest of the extant animals we studied and therefore the most basal living ancestor.” There are several ctenophores in Cornell’s collection, even though
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the Blaschkas could never have known, in 1868, that these represented the first branch on the animal tree of life. CNIDARIA
This phylum brings us to a close ctenophore relative, a giant phylum on the Blaschka tree of life that contains both the anemones and the jellyfishes. At 227 models, a big portion of our collection is made up of cnidarians. Both the beauty and the biological complexity of this group are dazzling, and it’s a daunting job to pick the most elemental characters and relationships. All the cnidarians are defined by having stinging capsules called nematocysts, described in detail in chapter 3. The stinging capsules are very similar in form and function to the ctenophore’s colloblasts, which secrete an adhesive (instead of a venom) for prey capture. The similarity in these capsules is more evidence for the close relationship between the cnidarians and ctenophores. The cnidarians come in two basic forms, either a medusa, also known as a jellyfish, or a polyp, also known as an anemone. They look vastly different, since the medusa floats and voyages the great oceans and the polyp sits rooted to the bottom and never goes anywhere. The seventy-one medusae or jellyfish are found in three distinct classes: the scyphozoans, the hydrozoans, and the cubozoans. The scyphozoans are the true ocean-going jellies; some, like the lion’s mane jellyfish, reaching sizes as big as a diver. Some species never touch the bottom in any part of their life cycle. One exception are the stauromedusae, which live attached to the bottom as a kind of upside-down jellyfish and have been recently elevated to their own class, the Staurozoa. The cubozoans are the rather lethal venomous box jellies, smaller than a mouse. But it’s the hydrozoans that are the most exciting group to me, because they include colonial forms made up of both the medusae and the polyp. They also
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Hydrozoa: Leuckartiara octona in glass, showing both the polyp and attached medusa. note the tiny “actual size” model in the lower left, which reveals how magnified the detail model is. photo courtesy of the Corning Museum of Glass.
include the siphonophores, famed as superorganisms and beloved by the Blaschkas for their complicated division of labor, as discussed in chapter 3. The hydrozoans are the pinnacle of complexity and coolness, and the hydrozoan medusae are the most intricate models in our collection. Think about how a bottom-dwelling hydrozoan colony starts from a single planktonic baby, much smaller than a ladybug, called a larva. This larva snuffles along the bottom until it finds a very good spot, and then it begins to bud. First it buds more polyps, which are good at catching food to fuel further expansion of the colony. After making enough food polyps, our growing colony makes special defensive polyps, and it finally ends by budding
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reproductive polyps. Here is the big surprise, the stuff of science fiction, and the reason I love this group so much: the reproductives are sometimes not polyps. They turn out as jellyfish that can stay attached to a branch. Or they can be polyps, but inside they grow tiny jellyfish that are released and swim away to release eggs and sperm to make new babies. What this means is that over evolutionary time, the genetic blueprint for making both a stationary polyp and a medusa has become integrated into a single animal’s genetic code. The anemones are in the class Anthozoa and also exist in several forms, starting with one simple polyp, like an anemone. The anthozoans are then divided into polyps with six- or eightfold symmetry. The anemones and reef-building corals are in the sixfold symmetry group (subclass Hexacorallia), and the soft corals with no calcareous skeleton and eight pinnate tentacles are in the eightfold group (subclass Octocorallia). Members of the Hexacorallia go from the form of an anemone to a reef-building coral simply by budding a lot of polyps that stay attached to each other, share food, and secrete a massive skeleton. PLATYHELMINTHES, NEMERTEA, PRIAPULIDA, AND ANNELIDA
The next major group to place on our tree of life includes the four phyla of worms. The extraordinary thing about the worm is that it is a life form that has evolved multiple times in different phyla, so worms are scattered all over our tree. The Blaschkas were extravagant in their efforts to instruct and inspire us about worms, which are all soft-bodied, and they included what were then five phyla of worms in their creations: Platyhelminthes (flatworms), Nemertea (ribbon worms), Priapulida (penis worms), Echiura (spoon worms), and Annelida (segmented worms). The flatworms
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platyhelminthes: the flatworm Acanthozoon ovale in glass. photo by david O. Brown.
have the simplest of worm body plans and are just worm-shaped sacs, a crawling stomach with a mouth and no exit, no anus. The Blaschkas seemed to like these simple flatworms and we have twenty-one in our collection. Next in complexity are the ribbon worms in the phylum Nemertea. They also tend toward flatness but are greatly elongated and stretchy. They are characterized by having a large eversible proboscis studded with huge venom-filled jaws. What more can I say about the appearance of the priapulids, also known as penis worms? They are a very small group but significant in that they molt and so are more closely related to the phylum containing crabs than to the other worms. I’ll bet most people are not familiar with the penis worms, nor with the spoon worms in the group Echiura. Back in the Blaschkas’ day, these were their own separate phylum. We now know they are one twig on the largest, most spectacular branch of worms on earth, the segmented annelid worms. Some scientists, such as my good friends and worm experts Sally Woodin and Rachel Merz, would say the most fabulous
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echiura: the spoon worm Bonellia viridis in glass. photo by elizabeth R. Brill.
of the Blaschka pieces—for their intricacy and sheer brilliance— are the marine segmented worms, within the class Polychaeta. The Blaschkas may well have agreed, since we have twenty-two of these very intricate worms in our collection, many painted or crafted from mixes of colored glass. Worm biodiversity is, paradoxically, one of my favorite themes in teaching invertebrate biodiversity, because of the very consistent, logical layout of the worm body plan and the absolutely delightful variations on the theme. How much fun it is to compare the variations in massive jaws and bristly parapodia among the powerful, mobile hunting worms and then move on to consider the evolutionary modifications of the array of sessile tube- and burrowdwelling worms. Worms do indeed come in these two types, the errant mobile worms and the sedentary ones (page 73). The great common families of mobile worms include the Nereids, the Glycerids, and the Phyllodocids. These are accompanied by the Blaschka models of the rarer and wonderful errant families the Syllids and the Hesionids. Some of the clam worms (nereids) can reach three feet long, and when picked up or attacking their prey,
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extrude a long proboscis with very visible black, curved teeth at the end. I dream there could be a human-sized one lurking in the deep somewhere. The diet of these mobile hunting worms includes other worms, corals, and small crabs. The other great arm of worm diversity encompasses the sedentary tube-dwelling worms, characterized by bright plumes of feeding tentacles, or by tentacle lines strung across the bottom of the ocean. I think of these in turn as being of two types, depending on whether they filter plankton from the water column with large ciliated plumes or dredge endlessly through the sand and mud with ciliated long strands. MOLLUSCA
The Mollusca are a huge, beloved phylum of spineless animals treasured for the spectacular shells made by snails and clams and the culinary heights reached by meals featuring oysters, clams, snails, and squid. They are closely related to the annelids in the large group Lophotrochozoa, which is characterized by shared patterns of embryonic and larval development, cementing our certainty that they are kin. Embryonic lophotrochozoans all develop by spiral cleaving, which means each new cell of the embryo comes off at a twist from the one below, and they can be asymmetrically sized. Both molluscs and annelids develop through a common larval stage called a trochophore, which can be either free swimming in the plankton or embedded in an egg case. Molluscs are divided into seven classes, the best known of which are the big five: the gastropods (including snails and sea slugs), bivalves, cephalopods (including octopus and squid), chitons, and tooth shells. Here is where we have a funny disconnect between the artistry of the Blaschkas and our tree of life. The Blaschkas focused on soft-bodied critters without shells, so they pretty much
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skipped the numerically dominant groups of molluscs like the bivalves, tooth shells, and chitons. They skipped most of the shelled snails, but focused in exciting detail on many soft-bodied molluscs within the gastropods, depicting the less-known sea slugs, including the brightly colored nudibranchs in their full glory. The Blaschkas produced so many of these different groups of soft-bodied sea slugs that it’s important to describe their relationships in some detail, although this repeats some of what I said in chapter 5. Sea slugs differ from shelled snails in having no shell and undergoing a mysterious process called detorsion. Shelled snails undergo torsion during development, so the back end with the anus ends up facing forward, on top of the body mass. This seems to help with positioning the body to carry a shell. Detorsion is an unwinding of this process and is a sign of an evolutionary transition. During development, a sea slug first undergoes normal torsion like a gastropod, and then undoes it in detorsion. The sea slugs include the sea butterflies, sea elephants, sacoglossans, and nudibranchs. The nudibranchs, so-called naked gills because the adults have no shell and their gills are often exposed as great plumes on their backs, are the single largest group in the Blaschka collection. As a group, nudibranchs are divided into families characterized by specific body forms and prey types, which are described in chapter 5. The prey taken by this group of fierce predators defies characterization and includes tube-dwelling anemones, soft corals, hydroids, and even, in the case of the hooded nudibranchs, small mobile crustaceans. The aeolids, often the most brilliantly colored, with fields of bright plumes on their backs called cerata, are well known for feeding on anemones, hydroids, and even jellyfish. They are master chemists and feed on the most chemically defended, toxic animals. Included in the sea slug chapter are other snail relatives that are closely related to the nudibranchs and share their absence or
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nudibranchia: the sea slug Plocamopherus imperialis in glass. photo by Kent Loeffler.
near absence of a shell. This includes the cephalaspids, or headshield slugs, the plant-eating sacoglossans, like the bright green Stilliger ornatus and the spotted Caliphylla tricolor, which are solar-powered by virtue of the algal cells they steal from their prey, and the plankton-dwelling pteropods, the sea butterflies and sea elephants. The pteropods are a group of sea slugs that include both shelled and unshelled forms. The lovely unshelled pteropods, called sea angels and represented in our collection by Clione limacina, are in fact vicious predators that fly through the water on a mission of death and literally tear apart shelled pteropods. As discussed in chapter 8, the shelled pteropods—the sea butterflies, in the genus Limacina—are the canary in the coal mine when it comes to the effects of ocean acidification. The sea elephant, Carinaria, I have never seen in nature. With its reduced shell and a special type of radula, it is actually closely related to shelled gastropods, as opposed to the shell-less opisthobranchs. This strange foot-long mollusc is pelagic, with a muscular ventral fin, but it swims upside down, hunting for prey in the plankton. It feeds on some unusual invertebrate chordates, arrow worms, and fish. The Blaschkas also went completely wild with the cephalopods, still within the phylum Mollusca. Although I know some things
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about invertebrate biodiversity, my specialty is corals, and I’m pretty good with nudibranchs, but as I wrote this book, I learned much about cephalopods from the Blaschkas. The cephalopods are divided into squid, octopus, cuttlefish, and nautilus. They are separated by their numbers and types of arms. The octopuses are distinctive in having eight arms and usually lacking fins. Then there are three groups that are quite closely related and to my eye overlap somewhat. The teuthid squid, as decapods, have ten arms—eight arms plus two specialized hunting or reproductive tentacles—and they have fins. The sepiolid squid are the adorable, puppy-like bobtail squid, in an order separate from the teuthid squid and having reduced fins, but still with ten arms or tentacles. The cuttlefish (order Sepiidae) also have eight arms and two tentacles and are distinguished by having an internal shell or cuttlebone. I’ve called the cuttlefish and octopus shape-shifters because of their surprising ability to transform from looking like a rock to a piece of drifting algae. Cuttlefish in particular are called chameleons of the sea because of their transformative color shifts. I am pleased to report we did it! Without your even realizing it, we just completed a survey of most of the great arm of invertebrates called the lophotrochozoans. We left out quite a few small groups, but that’s okay, since the Blaschkas did also. The Lophotrochozoa and the Ecdysozoa are the huge basal branches of the tree of life that form the earliest group of spineless animals, the protostomes. So to complete our look at protostomes, we need to consider the Ecdysozoa, the group defined by the necessity to molt or shed an exoskeleton. The Ecdysozoa include the very largest of all invertebrate animal groups, the arthropods, which is of course home to the insects. Here is my favorite part: the Blaschkas did not include any arthropods in their collection! There are no crabs, insects, shrimp, copepods, or barnacles. Leopold and Rudolf simply
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Cephalopoda: the squid Chtenopteryx sicula in glass. photo by david O. Brown.
excluded the crustaceans, the largest, most biodiverse group of spineless animals. They also left out the nematode worms, another large group of ecdysozoans. We assume the reason is that they wanted to focus on soft-bodied invertebrates, which are difficult to preserve. Perhaps they felt the world was already overrun with models of insects, crabs, and shrimp? At any rate, if you look at our evolutionary tree, the big branch for the ecdysozoans is devoid of glass models except for one, the penis worm, Priapulis caudatus, representing a rather diminutive phylum of wormlike invertebrates. Here is one seemingly small piece of soul that I share with the Blaschkas, but it feels like everything: We are rebellious and anachronistic and unruly and eclectic, driven by passion for what we love, and we love jellyfish, corals, nudibranchs, cephalopods, and even worms. We do not actually love crustaceans, and we are willing to leave them out. But I digress.
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Now that we have finished with the protostomes, we can launch into the group that humans belong to, the deuterostomes, the second major arm, or superphylum, that also encompasses spineless animals. Deuterostomes include echinoderms and chordates; the latter include us humans as well as the other vertebrates. Deuterostomes likely evolved from very early protostomes. They differ in the hidden but important details of their embryonic and larval development. In their very earliest development, the gastrula stage, the first opening into a protostome embryo will form the mouth, and the second opening will be the anus. The opposite is true for us deuterostomes: our butt forms first. (In Greek, deuterostome means “mouth second.”) This means that as deuterostome embryos, we are upside down relative to protostomes: our dorsal surface is their ventral surface. It’s probably okay if this revelation does not rock your world. ECHINODERMS
The Blaschkas selectively depicted animals from two of the deuterostome phyla, the chordates and the echinoderms. The echinoderm classes include sea stars, brittle stars, sea cucumbers, sea urchins, and feather stars. “Echinoderm” comes from the Latin echin- and -dermata, meaning spiny skin, and that’s what unites the group. The echinoderms are also united in having a water vascular system that controls the many tube feet they use for running around, or that the stars use for pulling open clams to eat. Showing their depth of knowledge, the Blaschkas focused on the lesser known soft-bodied part of this group and skipped the iconic sea urchins and made very few sea stars. The sea cucumbers look like worms but have rows of tube feet for mobility (except for a small group of apodous cucumber that are bereft of tube feet) and the same water vascular system as the other echinoderms. The sea
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Crinoidea: the sea feather Antedon mediterranea in glass. photo courtesy of the Corning Museum of Glass.
feathers, or crinoids, are distinguished by having a mouth on their top surface as opposed to underneath, as with most echinoderms. They have many arms, although these usually occur in multiples of five. The brittle stars, or ophiuroids, always have five long, jointed, whiplike arms. Many of the echinoderms are brightly colored and beautiful underwater, and the Blaschkas of course captured this in both glass and some rather magnificent watercolors. CHORDATES
The evolutionary apex of the deuterostome lineage includes the chordates and that “small” branch of vertebrates, which we won’t bother with here. The non-vertebrate branches of the chordates are mostly spineless, contained in a subphylum called the Urochordata.
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You may think that sea squirts do not hold any wonder for you, but wait until you observe how gloriously beautiful the sea squirts are and see how extraordinary the differences are among the three classes: the Ascidicea, the Larvacea, and the Thaliacea. An adult sea squirt gives few clues of its relatedness to us, but the larval form, called a tadpole larva, is a dead ringer for an adult salamander or a frog larva, also called a tadpole. Over evolutionary time, we humans lost most of our tail, but we do have a vestigial tailbone, a nerve cord, and a notochord in early development. A tadpole also has gills and gill arches, characteristics we share in early development. This is the imprint of evolution; these linkages show our shared ancestry. For those who balk at the idea of our close relationships with the apes, to be related to sea squirts has to be an even more bitter pill to swallow. There can be no denying, however, that these larvae show our shared ancestry. I see these signs of relatedness as truly comforting; we really are a part of this great kaleidoscope of creatures spun by evolution over eons of time. The sea squirts are the one group with a siphon on each side of this big divide of being spined or spineless. The cool part of their biology is that when the plankton-voyaging larva is ready to become an adult, it undergoes metamorphosis (like when a frog larva changes into an adult): using special suckers, it attaches to the sea bottom in a kind of headstand, sucking in its tail as the notochord dissolves and expanding the gill basket underneath its mighty new siphons, which will be used for processing millions of liters of water. Voilà, most vestiges of the chordate are gone, and we have a spineless sea squirt. An examination of the three classes of the chordates is, once again, a shocking stroll through big evolutionary changes in features. The basic body plan of a sea squirt, with a gill basket and notochorded larva, is transformed by evolution in different ways
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Chordata: the sea squirt Boltenia ovifera, or sea peach, in glass. photo by Gary Hodges.
in each of the classes. One class, the sea squirts, has an attached adult with a big gill basket and a small, brief swimming tadpole larva. Another class, called the salps, takes that attached adult and makes it a jet-propelled, transparent gill basket, swimming the open oceans. The final class, the larvaceans, loses the adult form and turns the tadpole larva into a reproducing adult. This process, by which a larval form evolves to become a reproducing adult, is called paedomorphosis. Another example of this, perhaps more familiar, is the life cycle of the axolotl (Mexican salamander or Mexican walking fish), where the adult retains the finned tail and gills of the larva and never metamorphoses into a form like other adult salamanders, with lungs and no tail fin. There is irony in the fact that the Blaschkas’ chordate offerings are very thin. This is our group on the tree of life, our closest kin, united with us in a few shared characteristics. Fittingly enough, our linkages with the spineless chordates hearken back to Ernst Haeckel’s controversial theme from 160 years ago: ontogeny recapitulates phylogeny. In this context, our phylogeny, or relatedness to sea squirts, is most closely revealed in early ontogeny, or when we are both larvae. While there are only a few spineless chordates in our Blaschka collection, the key classes are represented, ready to fit into our tree of life.
°
°
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It would be fun to share with the Blaschkas our brief primer on the spineless tree of life and the never-ending discoveries that stretch from before the 1860s and will continue well past our time. They would be entranced by the discoveries made over the past 160 years about relatedness among the spineless groups. I like to imagine their wonder at the discovery that ctenophores instead of sponges are the oldest invertebrates, that nematodes are most closely related to arthropods via the process of molting, and that most worms are far more closely related to nudibranchs and cephalopods than to crabs and insects. Most of the other facts about animal development and phylogeny are things the Blaschkas knew already and highlighted in their comprehensive collection.
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ILLU S TRATIONS
Page xii
Common octopus (Octopus vulgaris) in glass from the Cornell collection
Page 9
The Blaschkas in their Dresden garden, circa 1880–1891
Page 18
Sea pansy (Renilla muelleri) in glass
Page 20
Elegant anemones (Anthopleura elegantissima) in a Juan Island tide pool
Page 22
Lithographs of anemones in a tide pool, by Philip Henry Gosse
Page 23
Anemones in glass: snakelocks anemone (Anemonia viridis), beadlet anemone (Actinia equina), and Parantheopsis cruentata
Page 24
The swimming anemone (Stomphia coccinea) alive in the San Juan Islands and in glass
Page 27
Sea pens and sea pansies (Renilla muelleri) in a Blaschka watercolor
Page 34
Orange cup coral (Astroides calycularis) in glass
Page 40
A creamy bank of the giant plumose anemone (Metridium farcimen)
Page 42
Portuguese man-of-war (Physalia physalis) in glass
Page 44
Blaschka watercolors showing a diverse selection of jellyfish
Page 45
Lion’s mane jellyfish (Cyanea capillata) in a Blaschka watercolor and glass
Page 47
Siphonophores in glass: Apolemia uvaria and Rosacea cymbiformis
199
Page 55
The mauve stinger (Pelagia noctiluca): a live jellyfish in the Mediterranean, a Blaschka jellyfish in glass, and a Blaschka watercolor
Page 57
By-the-wind sailor (Velella velella) in glass and washed onto a Mediterranean beach
Page 65
Red-eye medusa (Polyorchis penicillatus) in a Blaschka watercolor and alive
Page 68
The tentacled tubeworm (Pista cretacea) in glass
Page 73
Worms in glass: Pherusa plumosa, Nereiphylla paretti, and Pista cristata alongside the sand grain tube it constructed
Page 76
The parchment tubeworm (Phyllochaetopterus major) in glass
Page 78
Burrowing lugworms in the family Arenicolidae: a Blaschka watercolor and live (Abarenicola pacifica)
Page 84
Serpula vermicularis in glass and a Blaschka watercolor
Page 88
Spotted sacoglossan (Caliphylla mediterranea) in glass
Page 94
The variable neon slug (Nembrotha kubaryana) in Indonesia’s Wakatobi Islands
Page 95
Facelina bostoniensis, a nudibranch from the aeolid family, in glass and alive at Shoals Marine Lab in New Hampshire
Page 96
The frond aeolis (Dendronotus frondosus) in a watercolor and alive
Page 97
The crowned doto (Doto coronata) in glass and alive at Shoals Marine Lab
Page 102
A sea dragon (Glaucus atlanticus) in glass and in a Blaschka watercolor
Page 105
Sponge-eating nudibranchs in the Wakatobi Islands: Goniobranchus leopardus and Kuni’s nudibranch (G. kuniei) near Kapota Island, and Anna’s chromodoris (Chromodoris annae)
Page 108
Clione limacina, a sea angel, in glass and alive at Friday Harbor
Page 112
The long-armed squid (Chiroteuthis veranyi) in glass
200
I l l u s t r at I o n s
Page 117
The Blaschkas’ jeweled umbrella squid (Histioteuthis bonnellii) before and after restoration
Page 118
Cephalopods in glass: the common clubhook squid (Onychoteuthis banksia), stout bobtail squid (Rossia macrosoma), elegant cuttlefish (Sepia elegans), fourhorn octopus (Pteroctopus tetracirrus), curly tentacle octopus (Eledone moschata), and blanket octopus (Tremoctopus violaceus)
Page 121
Blaschka watercolor of a male argonaut and a Blaschka glass model of a female argonaut (Argonauta argo)
Page 123
The ornate octopus (Callistoctopus ornatus) and day octopus (Octopus cyanea) in Hawaii
Page 136
The common sea star (Asterias rubens) as a juvenile in glass
Page 140
Feather stars feeding on a reef in Bali and on a high current wall near Kapota Island, Indonesia
Page 143
Echinoderm diversity in glass: Mediterranean crinoid Antedon mediterranea, brittle star Ophiothrix serrata, sea cucumber Synapta fasciata, and sea cucumber Trachythyone peruana
Page 145
Ophiothrix serrata brittle star before and after restoration
Page 145
Daisy brittle star (Ophiopholis aculeata) in glass and alive in Friday Harbor, Washington
Page 147
Healthy populations of the keystone star Pisaster ochraceus eating back the mussel bed in Bamfield, British Columbia
Page 152
The Mediterranean coral Dendrophyllia ramea in glass
Page 154
A zebra slug (Felimare picta) on an underwater cliff in the Mediterranean
Page 165
Projected effects of four different emission reduction scenarios on atmospheric CO2 concentration and mean global temperature
Page 170
The tree of spineless life, rendered in Blaschka glass
Page 175
Ctenophora: Hormiphora plumosa in glass
Page 177
Hydrozoa: Leuckartiara octona in glass, showing the polyp and attached medusa
I l l u s t r at I o n s
201
Page 179
Platyhelminthes: the flatworm Acanthozoon ovale in glass
Page 180
Echiura: the spoon worm Bonellia viridis in glass
Page 183
Nudibranchia: the sea slug Plocamopherus imperialis in glass
Page 185
Cephalopoda: the squid Chtenopteryx sicula in glass
Page 187
Crinoidea: the sea feather Antedon mediterranea in glass
Page 189
Chordata: the sea squirt Boltenia ovifera, or sea peach, in glass
202
I l l u s t r at I o n s
INDEX
abalone, 150 Abarenicola pacifica, 78 fig. acidification. See ocean acidification acorn worms, 77, 79 Actinia equina (beadlet anemone), 21, 23 fig. Actinoloba dianthus, 36 See also Metridium senile Actinologia Britannica: A History of the British Sea-Anemones and Corals (Gosse), 6–7, 20, 22 fig., 58 Aeolidia papillosa, 97 aeolid nudibranchs, 93, 97, 182 Aequorea victoria (crystal jelly), 64 Agassiz, Louis, 58 alabaster nudibranch, 39 Alder, Joshua, 94 algae, 158, 164, 183 symbiosis with anemones and corals, 11, 19–20, 26–27, 28 Alitta succinea, 77 amphibians, disease in, 150, 162–63 Ancistroteuthis lichtensteinii, 115–16 anemones, 19–26, 53–54, 176 biology and behavior, 19–21, 24– 26, 176, 178 in glass, 7, 21, 23 fig., 24 fig., 35– 36, 173
in search of Blaschka matches, 35–41 as nudibranch prey, 90, 93, 97 photographs, 20 fig., 24 fig. threats and conservation status, 156–57 in watercolors and lithographs, 6–7, 20–21, 22 fig., 58 See also specific taxa Anemonia viridis (snakelocks anemone), 21, 23 fig. Anna’s chromodoris (Chromodoris annae), 99, 104, 105 fig. annelid worms, 74, 84, 178, 179–80, 181 See also specific taxa Antedon mediterranea, 143 fig., 187 fig. Anthopleura ballii, 19, 21 Anthopleura elegantissima (elegant anemone), 19–20, 20 fig., 97 anthozoans, 170 fig., 178 antimicrobial chemicals, 74, 100 Apolemia, 44–45, 46, 47 fig., 60 Arenicola, 70, 77–78, 78 fig., 81–82 Arenicolidae (lugworms), 70, 72, 77– 78, 78 fig., 81–82 Argentine shortfin squid (Illex argentines), 132
203
argonaut (Argonauta argo), 119–20, 121 fig., 133, 158 armored sea cucumber, 39 arthropods, 184–85, 190 ascidians, 54, 170 fig., 188 See also sea squirts Aspergillus, 32 Asterias rubens (common sea star), 136 fig., 148 Astroides calycularis (orange cup coral), 33, 34 fig., 53, 54, 158, 159 Aurelia aurita (moon jelly), 41, 46, 66 Axinella, 159 axolotl, 189 bacteria antimicrobial chemicals, 74, 100 Vibrio fischeri and squid bioluminescence, 126–27 Balanophyllia europaea (solitary cup coral), 158, 159 Balanophyllia regia (golden star coral), 54 Bali dives, 136, 137–39 beadlet anemone (Actinia equina), 21, 23 fig. biodiversity. See marine biodiversity biofuels, from marine sources, 164 bioluminescence, 19, 45, 49–50, 52, 64, 126–27 biomimicry, 101, 122, 151 bivalves, 181, 182, 184 blanket octopus (Tremoctopus violaceus), 118 fig., 120 Blaschka, Joseph, 5 Blaschka, Leopold, 5–9, 9 fig., 36, 49–50, 57, 58–59, 127, 156 Blaschka, Rudolf, 6, 7, 8–9, 9 fig., 58, 59, 127, 155–56 Blaschka correspondence and journals, 5, 7, 8, 36, 49–50, 58–59, 155
204
INDEX
Blaschka glass models, 1–12, 171–74 background and techniques, 5–9, 49 Cornell collection, 1–5, 10–11, 12, 173 damage and restoration, 1–2, 3, 4–5, 10–11, 117, 142–43, 145 fig. efforts to find living matches, 2, 13–14, 15–16, 153–55 extent and diversity of, 3–4, 7, 14, 173–74, 181–82, 184–85, 189 flowers and plants, 4, 6, 58 name and taxonomic changes, 15, 81 other artists’ influences on, 3, 6–8, 21, 57–61, 94–95 value and influence of, 10–13, 127 watercolor studies for, 8–10, 21 See also specific marine taxa Blaschka watercolors, 8–10, 21 jellyfish, 44 fig., 45 fig., 55 fig., 65 fig. octopuses, 119–20, 121 fig. other artists’ influences on, 3, 6–8, 21, 57–61, 94–95 sea pens and sea pansies, 18 fig., 27 fig. sea slugs, 94–95, 102 fig. worms, 9–10, 78 fig., 84 fig. blast fishing, 11, 90–91, 111 bloodworms, 71, 72 bluefin tuna, 160 Blue Wilderness Divers, 114 bobtail (sepiolid) squid, 126, 154, 184 Rossia macrosoma, 116, 118 fig., 126 Boero, Fernando, 64 Boltenia ovifera (sea peach), 189 fig. Bonellia viridis (green spoon worm), 74, 180 fig.
bonnelin, 74 box jellies (cubomedusans), 46, 51, 176 Brill, Elizabeth, 10, 117 bristle worms, 72 brittle stars (ophiuroids), 142–44, 151, 154, 161, 170 fig., 173, 186 biology and behavior, 143–44, 151, 173, 187 in glass, 142–43, 143 fig., 145 figs. Brown, David, 2, 13 bull shark, 29–30, 31, 48 Burge, Colleen, 149 burrowing worms. See worms; specific taxa butterflies, 100 by-the-wind sailor (Velella velella), 56, 57 fig., 60, 101, 154 calcification, CO2 levels and, 29, 34–35, 161 Caliphylla mediterranea (spotted sacoglossan), 88 fig. Caliphylla tricolor, 183 Callistoctopus ornatus (ornate octopus), 114–15, 123–24, 123 fig. Campbell, Katie, 148 carbon dioxide levels, 28–29, 33, 34– 35, 157, 160, 161 future scenarios, 163–64, 165 fig. See also climate change impacts; ocean acidification; ocean warming; warming Carinaria (sea elephant), 182, 183 caterpillars, 100 Cattaneo-Vietti, Riccardo, 89 Centro Ricerche Ambiente Marino di Santa Teresa dell’ENEA, 52 cephalaspids (head-shield slugs), 183 cephalopods, 112–35, 173, 181, 183– 84, 190
biology and behavior, 117, 119, 120–22, 127–28, 131–32, 184 in glass, 115–16, 127, 173, 183–84 in Indonesian waters, 89, 128–31, 134–35 in search of Blaschka matches, 113–15, 123–26, 128–31, 134–35 as jellyfish predators, 66 in Mediterranean, 126, 154, 157, 158, 159 photographs, 118 fig. threats and conservation status, 131–34, 157, 158, 159–60 in watercolor, 121 fig. See also cuttlefish; octopuses; squid; specific taxa Cerianthus membranaceaus, 53 Cestum veneris (Venus girdle ctenophore), 51 Chaetopteris variopedatus (parchment tubeworm), 76, 79 Chiroteuthis veranyi (long-armed squid), 112 fig., 116, 158 chitons, 181, 182 chordates, 173, 187–89 See also salps; sea squirts Christmas anemone (Urticina crassicornis), 36, 40 chromatophores, 122 chromodorid nudibranchs, 93, 99, 100, 101, 104, 105 fig. Chromodoris annae (Anna’s chromodoris), 99, 104, 105 fig. Chtenopteryx sicula, 185 fig. chytrid fungus, 150, 162–63 clam worms (nereids), 71, 73 fig., 77, 79, 82, 180–81 climate change impacts, 157, 161–62 on coral reefs, 28–35, 150, 157, 158, 159
INDEX
205
climate change impacts (continued) jellyfish and, 63–64 on Mediterranean marine life, 158, 159, 160 sea star wasting and, 150 worms and, 81–82 See also carbon dioxide levels; ocean acidification; ocean warming; warming Clione limacina, 107, 108 fig., 183 clown fish, 106 clown nudibranch, 39 cnidarians, 24, 103, 173, 176–78 sea pansies, 18 fig., 26–27, 27 fig. sea pens, 27 fig. See also anemones; corals; jellyfish; specific taxa coastal disturbance and pollution, 32, 83, 92–93, 131, 150, 156 Cocito, Sylvia, 52 cod, 163 colonial organisms corals as, 26 jellyfish as, 43, 44, 56, 60–61, 176– 78, 177 fig. coloration cephalopods, 121–22, 184 mimicry, 101, 122, 151 nudibranchs, 101 sea cucumbers, 151 comb jellies (ctenophores), 50–51, 52, 170 fig., 174–76, 175 fig., 190 common clubhook squid (Onychoteuthis banksia), 118 fig. common octopus (Octopus vulgaris), 113–14, 120–21, 128, 132, 154 in glass, xii fig., 1–2, 10–11, 115 common sea star (Asterias rubens), 136 fig., 148 Corallium rubrum (precious red coral), 63, 159
206
INDEX
Coral Reef Rehabilitation and Management (COREMAP) sites, 92 corals, 25, 26–35, 178 biology and ecology, 25, 26–27, 138–39, 178 CO2 sensitivity, 161 current conservation status, 28– 29, 33–35, 133, 150, 153, 158, 159 in glass and watercolor, 34 fig., 152 fig. in Indonesia, 11, 90–91, 92–93, 99, 106–7, 138 living Blaschka matches, 33, 53, 54, 63, 158, 159 in Mediterranean, 33, 53, 54, 153, 154, 158, 159 threats and declines, 11, 28–35, 90–91, 92–93, 106–7, 150, 157, 158, 159 See also specific taxa Coral Triangle, 11, 90, 91, 138 See also Indonesian dives COREMAP (Coral Reef Rehabilitation and Management) sites, 92 Corning Museum of Glass, 5, 8, 115, 143 crabs, 160 crayfish, 160 crinoids (sea feathers, feather stars), 99, 137, 173 biology and behavior, 138, 139, 142, 186–87 in glass, 143 fig., 187 fig. photographs, 140 fig. crowned doto (Doto coronata), 95, 97 fig. crustaceans, 184–85 crystal jelly (Aequorea victoria), 64
ctenophores (comb jellies), 50–51, 52, 170 fig., 174–76, 175 fig., 190 cubozoans (cubomedusans)(box jellies), 46, 51, 176 curly tentacle octopus (Eledone moschata), 118 fig., 154 cuttlefish, 154 biology and behavior, 119, 121–22, 134–35, 184 conservation status, 133–34, 157 in glass, 118 fig., 132 See also cephalopods; specific taxa Cyanea capillata (lion’s mane jellyfish), 45 fig., 176 daisy brittle star (Ophiopholis aculeata), 144, 145 fig. Darwin, Charles, 61 day octopus (Octopus cyanea), 113, 114, 123 fig., 124–26 Deane, Walter, 155 dendronotid nudibranchs, 93 Dendronotus frondosus (frond aeolis), 94, 96 fig. Dendrophyllia ramea, 152 fig. deuterostomes, 186 See also specific taxa dinoflagellates, 19, 158 Dioum, Baba, 10 Discodoris atromaculata (sea cow), 153 disease, 150–51 in corals, 32, 150 ocean warming and, 162–63 sea star wasting, 146–50, 163 dolphins, 160 Doridella steinbergae, 98 dorid nudibranchs, 93 Dosidicus gigas (Humboldt squid), 132
Doto coronata (crowned doto), 95, 97 fig. Dresden Botanical Garden and Natural History Museum, 6–7, 24 Dublin Natural History Museum, 35–36 E. coli, 100 ecdysozoans, 184–85 echinoderms, 136–51, 173 biology and behavior, 138, 139, 141–44, 151, 186–87 ecological importance, 142, 144, 146 in glass, 139, 143 fig., 186, 187 in search of Blaschka matches, 137–39, 151 photographs, 140 fig., 145 fig. threats and conservation status, 146–51 See also brittle stars; crinoids; sea cucumbers; sea stars; other specific taxa Echiura (spoon worms), 74, 170 fig., 178, 179, 180 fig. ecosystem engineers, 82–83, 142 Edwards, Milne, 58 Eisenlord, Morgan, 149 Eledone cirrhosa, 132 Eledone moschata (curly tentacle octopus), 118 fig., 154 elegant anemone (Anthopleura elegantissima), 19–20, 20 fig., 97 elegant cuttlefish (Sepia elegans), 118 fig. El Niño events, 29, 32–33 endangered species and ecosystems, 159–60 IUCN Red List, 133–34, 159–60 See also marine biodiversity declines; specific taxa
INDEX
207
eugenics, 61 Eunicella verrucosa (sea whip), 159 evolutionary relationships. See tree of life evolutionary theory, Haeckel’s theories and their influence, 57–58, 61 Facelina bostoniensis, 94–95, 95 fig. feather duster worms, 9–10, 54, 85, 154 Serpula vermicularis, 54, 70, 83, 84 fig., 85, 86 feather stars. See crinoids Feeny, Paul, 2, 3 Felimare picta (zebra slug), 153, 154 fig. Finnerty, John, 175 fire coral, 103, 104 fisheries declines, 65–66, 163 cephalopods and, 132, 133 Indonesia, 90–91 jellyfish and, 56, 63–64 Mediterranean, 56, 63, 66, 132, 160 fisheries policy, 163 flatworms (Platyhelminthes), 101, 178–79, 179 fig. flowers, Blaschka glass models of, 4, 6, 58 fourhorn octopus (Pteroctopus tetracirrus), 118 fig. Friday Harbor Labs, 19, 64, 175 frogs, 150, 162–63 frond aeolis (Dendronotus frondosus), 94, 96 fig. fungal disease, 32, 150, 162–63 gastropods, 170 fig., 173, 181, 182–83 See also nudibranchs; sea slugs; specific taxa Germany, Social Darwinism in, 61
208
INDEX
GFP (green fluorescent protein), 19, 64 giant plumose anemone (Metridium farcimen), 37, 39–40, 40 fig., 41 Giovine, Ferdinando, 89 Glaucus atlanticus (sea dragon), 10, 101, 102 fig., 103 global warming. See climate change Glynn, Peter, 30, 31 golden star coral (Balanophyllia regia), 54 Goniobranchus kuniei (Kuni’s nudibranch), 105–6, 105 fig. Goniobranchus leopardus (leopard of the sea), 105, 105 fig., 106 gorgonian corals, 63, 159 See also sea fans Gosse, Phillip Henry, 3, 6–7, 20–21, 22 fig., 58 great white shark, 48 Greene, Chuck, 146 green fluorescent protein (GFP), 19, 64 green spoon worm (Bonellia viridis), 74, 180 fig. Haeckel, Ernst, 3, 8–9, 57–61, 95, 116 hake, 160 Halichondria, 100 Halistemma rubrum, 60–61 Hancock, Albany, 94 Hanlon, Roger, 122 Harvard glass flower collection, 4 Hatziolos, Marea, 33 Havenhand, Jon, 162 Hawaiian bobtail squid, 126 Hawaiian dives, 43, 48–52, 113–15, 123–26 head-shield slugs (cephalaspids), 183 Hewson, Ian, 149
Hexabranchus sanguineus (Spanish dancer), 100 Hexacorallia, 178 See also corals; specific taxa Histioteuthis bonnellii ( jeweled umbrella squid), 117 fig., 158 Hooten, Andy, 33 Hormiphora plumosa, 175 fig. human biology and evolution, 176, 183, 188, 189 Humboldt squid (Dosidicus gigas), 132 hydroids, 26, 103, 182 hydrozoans (hydromedusae), 44, 60, 170 fig., 176–78, 177 fig. Illex argentines (Argentine shortfin squid), 132 Illex coindetii, 132 illustrations. See Blaschka watercolors; watercolors and prints Indonesian blast fishing, 11, 90–91, 111 Indonesian dives cephalopod search, 128–29, 134–35 echinoderm search, 137–39, 151 nudibranch search, 89, 92–93, 98– 101, 103, 104–6, 110–11 spawning worms sighting, 79–81 Intergovernmental Panel on Climate Change, 161–62 CO2 emissions projections, 165 fig. International Union for Conservation of Nature, 66, 84 Red List, 133–34, 159–60 Irukandji jelly, 45–46, 51 Italian dives. See Mediterranean dives James, Laura, 146, 148 Japanese flying squid (Todarodes sagittatus), 132
jellyfish, 42–66, 154, 176–78 biology and behavior, 43–46, 49– 50, 54–56, 60–61, 62–64, 176–78 in glass, 8, 10, 42 fig., 45 fig., 47 fig., 55 fig., 57 fig., 173, 177 fig. Haeckel’s influence on Blaschka models, 57–61 in search of Blaschka matches, 43, 48–56, 62, 63, 154 as nudibranch prey, 90, 101, 103–4 paper nautilus and, 158 photographs, 55 fig., 57 fig., 65 fig. threats and conservation status, 64–66, 156 in watercolor, 44 fig., 45 fig., 55 fig., 65 fig. See also specific taxa jeweled umbrella squid (Histioteuthis bonnellii), 117 fig., 158 keystone species, 144 Kim, Catherine, 43, 48, 49 Kim, Kiho, 32 Kuni’s nudibranch (Goniobranchus kuniei), 105–6, 105 fig. Kunstformen der Natur (Art Forms of Nature) (Haeckel), 57 Lanice conchilega (sand mason worm), 82–83 larvaceans, 170 fig., 188, 189 See also sea squirts leopards of the sea (Goniobranchus), 105, 105 fig., 106 Leuckartiara octona, 177 fig. Limacina, 183 limpets, 161 lionfish, 103, 105 lion’s mane jellyfish (Cyanea capillata), 45 fig., 176
INDEX
209
lobate ctenophores, 50–51 Loligo forbesi, 132 Loligo vulgaris, 132 long-armed squid (Chiroteuthis veranyi), 112 fig., 116, 158 lophotrochozoans, 181, 184 See also specific taxa lugworms (Arenicolidae), 70, 72, 77– 78, 78 fig., 81–82 manoalide, 100 marine biodiversity, 11, 15, 52, 91–92, 106–7, 138 marine biodiversity declines, 156–66 factors in, 156, 157, 158, 160–63 Mediterranean declines since the Blaschkas’ day, 156–60 vertebrate declines, 65–66, 150, 160 See also climate change impacts; fisheries declines; ocean acidification; specific taxa mauve stinger (Pelagia noctiluca), 46, 54–56, 55 fig., 63, 64, 66, 154 McFall-Ngai, Margaret, 126–27 Mediterranean dives, 153–55, 164, 166 jellyfish search, 52–56, 62, 63 Mediterranean feather duster, 54 Mediterranean fishery declines, 56, 63, 66, 132, 160 Mediterranean invertebrate declines, 156–60 medusae, 43, 44, 175 See also jellyfish Membranipora membranacea, 98 metamorphosis, 188 Metridium farcimen (giant plumose anemone), 37, 39–40, 40 fig., 41 Metridium senile (plumose anemone), 35–37, 41, 97
210
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Mexican salamander, Mexican walking fish, 189 Mills, Claudia, 64–65 mimicry, 101, 122, 151 mobile worms, 71–72, 180–81 See also worms; specific taxa molluscs, 109–10, 173, 181–86 See also cephalopods; sea slugs; other specific taxa molting, 185, 190 monarch butterfly, 100 Monograph of the British Nudibranchiate Mollusca (Alder and Hancock), 94–95, 96 fig. Monterey Bay Aquarium, 128 moon jelly (Aurelia aurita), 41, 46, 66 moray eel, 103 mottled star, 148 Naples Zoological Station, 7 Die Natur als Künstlerin (Nature as an Artist) (Haeckel), 58 nematocysts, 25, 60, 104, 176 See also toxins; venomous animals nematode worms, 185, 190 Nembrotha kubaryana (variable neon slug), 94 fig. Nemertea (ribbon worms), 170 fig., 178, 179 nereid worms (clam worms), 71, 73 fig., 77, 79, 82, 180–81 Nereiphylla paretti, 73 fig. notochord, 188 nuclear plant closures, 46 nudibranchs, 10, 190 biology and behavior, 10, 90, 93– 95, 97–98, 99–101, 103–4, 182 diversity and value of, 106–7, 110–11
in glass, 93–94, 95 fig., 96 fig., 102 fig., 183 fig. in search of Blaschka matches, 89, 92–93, 98–101, 103, 104–6, 110–11 in Mediterranean, 154–55, 157, 158, 159 photographs, 94 fig., 95 fig., 96 fig., 105 fig., 154 fig. in Salish Sea, 39, 40, 94 threats and conservation status, 90–91, 109–10, 111, 157, 159 in watercolor, 94–95, 96 fig., 102 fig. See also sea slugs; specific taxa ocean acidification, 107–8, 157, 160– 61, 162, 183 cephalopods and, 133 corals and, 28, 29, 33 sea slugs and, 107–10 sea stars and, 149–50 worms and, 82 ocean pollution, 156 See also coastal disturbance and pollution ocean warming, 28–29, 33–34, 157, 158, 160, 162–63 ochre star (Pisaster ochraceus), 141, 144, 146, 147 fig., 149 octocorals, 32, 178 See also corals; specific taxa Octopus cyanea (day octopus), 113, 114, 123 fig., 124–26 octopuses, 14, 154, 170 fig., 184 biology and behavior, 113, 115, 119, 120–21, 122, 128 in glass, xii fig., 1, 11, 115–16, 118 fig., 120, 121 fig. in search of Blaschka matches, 113–15, 123–26, 128–31
photographs, 123 fig. threats and conservation status, 128, 130–34, 157, 158 in watercolor, 119–20, 121 fig. See also cephalopods; specific taxa Octopus vulgaris (common octopus), 113–14, 120–21, 128, 132, 154 in glass, xii fig., 1–2, 10–11, 115 omastrephid squid, 132 Onychoteuthis banksia (common clubhook squid), 118 fig. Ophiopholis aculeata (daisy brittle star), 144, 145 fig. Ophiothrix serrata, 142–43, 143 fig. ophiuroids. See brittle stars orange cup coral (Astroides calycularis), 33, 34 fig., 53, 54, 158, 159 ornate octopus (Callistoctopus ornatus), 114–15, 123–24, 123 fig. oysters, 157 paedomorphosis, 189 Paine, Bob, 144, 146 palolo worms, 80–81, 83 paper nautilus (argonaut), 119–20, 121 fig., 133, 158 Paramuricea clavata (purple gorgonian), 63 Parantheopsis cruentata, 23 fig. parchment tubeworms, 76, 76 fig., 79 Pelagia noctiluca (mauve stinger), 46, 54–56, 55 fig., 63, 64, 66, 154 penis worms (priapulids), 170 fig., 178, 179, 185 Perinereis cultrifera, 71 pharmaceuticals, derived from marine animals, 74, 100 Pherusa plumosa, 70–71, 73 fig. Phyllidia, 104–5 Phyllochaetopterus major (parchment tubeworm), 76, 76 fig.
INDEX
211
Physalia physalis. See Portuguese man-of-war Pisaster ochraceus (ochre star), 141, 144, 146, 147 fig., 149 Pista cretacea (tentacled tubeworm), 68 fig., 82 Pista cristata (sand worm), 73, 73 fig. plants and flowers, Blaschka glass models of, 4, 6, 58 Platyhelminthes (flatworms), 101, 178–79, 179 fig. Plocamopherus imperialis, 183 fig. plumose anemone (Metridium senile), 35–37, 41, 97 Polychaeta, 170 fig., 180 See also worms Polyorchis penicillatus (red-eye medusa), 65, 65 fig. polyps, 176 anemones and corals, 19, 25, 26–27, 176 jellyfish, 44–45, 176, 177–78, 177 fig. Porifera. See sponges Porpita, 101, 103 Portuguese man-of-war (Physalia physalis), 44, 51, 66 biology and behavior, 43, 62–63 Blaschka’s observation of, 6, 49 in glass, 10, 42 fig., 60 as nudibranch prey, 10, 101 precious red coral (Corallium rubrum), 63, 159 predator-prey interactions, 10, 97– 98, 100–101, 103–4, 106–7, 182 priapulids (penis worms), 170 fig., 178, 179, 185 Priapulis caudatus, 185 prints. See watercolors and prints Prosek, James, 12–13 protostomes, 184 See also specific taxa
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Pteroctopus tetracirrus (fourhorn octopus), 118 fig. pteropods, 107–9, 108 fig., 183 See also sea angels; sea butterflies purple gorgonian (Paramuricea clavata), 63 purple sea fan, 32 Pycnopodia helianthoides (sunflower star), 141, 149 Quirolo, Craig, 32 Rakow Museum and Library, 7, 8 rays, 160 recapitulation theory, 57–58 red-eye medusa (Polyorchis penicillatus), 65, 65 fig. red tides, 158 Reichenbach, Heinrich Gottlieb Ludwig, 6, 7, 24 Reiling, Henri, 5, 7, 58 See also Blaschka correspondence and journals Renilla muelleri (sea pansy), 18 fig., 27 fig. ribbon worms (Nemertea), 77, 170 fig., 178, 179 Riegel, Carolina, 6, 9 fig. Robison, Bruce, 116 Rohan, Camille de, Prince, 6 Rosacea cymbiformis, 47 fig., 60 Rossia macrosoma (stout bobtail squid), 116, 118 fig., 126 sacoglossans, 93, 182, 183 See also sea slugs; specific taxa salamanders, 150 salmon kills, 46 salps, 158, 189 sand mason worm (Lanice conchilega), 82–83
sand worm (Pista cristata), 73, 73 fig. Schleiden, M. J., 80 scyphozoans (scyphomedusae), 43– 44, 170 fig., 176 sea angels, 107, 108 fig., 183 sea bass, 160 sea butterflies, 93, 107, 157, 161, 182, 183 sea cow (Discodoris atromaculata), 153 sea cucumbers, 39, 129, 170 fig., 173, 186 biology and behavior, 40–41, 139, 142, 151, 173, 186 in glass, 142, 143 fig. sea dragon (Glaucus atlanticus), 10, 101, 102 fig., 103 sea elephant (Carinaria), 182, 183 sea fans, 32 See also gorgonian corals sea feathers. See crinoids sea pansies, 18 fig., 26–27, 27 fig. sea peach (Boltenia ovifera), 189 fig. sea pens, 27 fig. sea slugs, 88–111, 182–83 biology and behavior, 89–90, 182 diversity of, 90, 91 photographs, 94 fig., 95 fig., 96 fig., 108 fig. sea angels and sea butterflies, 93, 107–9, 108 fig., 157, 161, 182, 183 taxonomy of, 93–94, 182–83 in watercolor, 94–95, 96 fig., 102 fig. See also nudibranchs; other specific taxa sea snakes, 103 sea squirts, 39, 40, 54, 106–7, 188– 89, 189 fig. See also ascidians
sea stars, 136 fig., 147 fig., 154–55, 173, 186 biology and behavior, 141–42, 173 ecological importance, 144, 146 threats and conservation status, 137, 141, 146–51, 163 See also echinoderms; specific taxa sea star wasting, 146–50, 163 sea urchins, 142, 162, 186 sea whip (Eunicella verrucosa), 159 segmented worms (Annelida), 74, 84, 178, 179–80, 181 See also specific taxa semelparity, 120–21, 131–32 Sepia elegans (elegant cuttlefish), 118 fig. Sepia officinalis, 132 Sepiidae. See cuttlefish sepiolid (bobtail) squid, 126, 154, 184 Rossia macrosoma, 116, 118 fig., 126 Serpula vermicularis, 54, 70, 83, 84 fig., 85, 86 sharks, 29–30, 31, 48, 66, 160, 163 Shimomura, Osamu, 64 Shoals Marine Lab, 69, 95 siphonophores, 49, 59–61, 176–77 biology and behavior, 44–45, 51– 52, 60–61, 62–63 in glass, 44–45, 47 fig., 59–60 See also specific taxa snails, 161, 181, 182 snakelocks anemone (Anemonia viridis), 21, 23 fig. Social Darwinism, 61 solar energy, 19–20, 26–27, 183 solitary cup coral (Balanophyllia europaea), 158, 159 Spanish dancer (Hexabranchus sanguineus), 100 spiral cleaving, 181 Spirorbis, 9, 72, 85
INDEX
213
sponges, 154, 159, 174–75, 190 as nudibranch prey, 99, 100, 104, 106–7 spoon worms, 74, 170 fig., 178, 179, 180 fig. spotted sacoglossan (Caliphylla mediterranea), 88 fig. squid, 132, 154, 170 fig. biology and behavior, 115–16, 117, 126–27, 184 in glass, 7, 112 fig., 115–16, 117 fig., 118 fig., 126, 132, 185 fig. threats and conservation status, 132, 133, 134, 157, 158 See also cephalopods; specific taxa staurozoans (stauromedusae), 176 Stazione Zoologica Anton Dohrn, 52 Stilliger ornatus, 183 Stomphia coccinea (swimming anemone), 21, 24, 24 fig., 25, 40 stout bobtail squid (Rossia macrosoma), 116, 118 fig., 126 Stronglylocentrotus nudus, 162 stumpy-spined cuttlefish, 134–35 sunflower star (Pycnopodia helianthoides), 141, 149 Swalla, Billie, 175 swimming anemone (Stomphia coccinea), 21, 24, 24 fig., 25, 40 syllid worms, 180 symbiosis algae-coral and algae-anemone symbiosis, 11, 19–20, 26–27, 28 squid bioluminescence as, 126–27 Synapta fasciata, 142, 143 fig. Synapta lamperti, 151 Das System der Medusen (Haeckel), 59 tadpoles, 188, 189 Tealia crassicornis (Christmas anemone), 36, 40
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tentacled tubeworm (Pista cretacea), 68 fig., 82 teuthid squid, 184 See also specific taxa Thaliacea, 188 See also salps Thayer, Charlie, 39 threatened and endangered species and ecosystems, 159–60 IUCN Red List, 133–34, 159–60 See also marine biodiversity declines; specific taxa tiger shark, 48 Todarodes sagittatus (Japanese flying squid), 132 tooth shells, 181, 182 torsion, 182 toxins toxic prey, 10, 100–101, 103–4, 106–7, 182 See also venomous animals Trachythyone peruana, 142, 143 fig. tree of life, 170 fig., 171–73 overviews of marine phyla, 174–84 Tremoctopus violaceus (blanket octopus), 118 fig., 120 trochophores, 181 Troll, Ray, 171 tube anemones, 53 tubeworms, 54, 180, 181 in glass and watercolor, 68 fig., 70– 71, 76 fig., 84 fig. See also feather duster worms; specific taxa tuna, 160 Twenty Thousand Leagues under the Sea (Verne), 119
urochordates, 187–89, 189 fig. Urticina crassicornis (Christmas anemone), 36, 40 USS Ronald Reagan, 46 variable neon slug (Nembrotha kubaryana), 94 fig. Velella velella (by-the-wind sailor), 56, 57 fig., 60, 101, 154 venomous animals, 103 anemones as, 25–26 jellyfish as, 45–46, 51, 54–56, 60– 61, 62, 101 nudibranchs as, 90, 93, 104 as prey, 10, 100–101, 103–4, 106–7, 182 worms as, 74 Venus girdle ctenophore (Cestum veneris), 51 Verne, Jules, 119 Vibrio fischeri, 126–27 Wakatobi National Park (Indonesia), 89, 90, 91–92 See also Indonesian dives Wallace, Alfred Russel, 91 Wallace Line, 91–92 Ware, Mary, 155 warming, 33, 160 ocean warming, 28–29, 33–34, 157, 158, 160, 162–63 See also climate change impacts; ocean acidification
watercolors and prints, 3 other artists’ influences on Blaschkas, 3, 6–8, 21, 57–61, 94–95 See also Blaschka watercolors whales, 160 White, Andrew Dixon, 3 Williams, R., 175 Woodin, Sally, 73, 81 World Bank, 33 worms, 68–86, 170 fig., 178–81, 190 biology and behavior, 71–72, 73, 74, 77–79, 80–81, 178–79, 180–81 diversity and value of, 77, 83–84, 180–81 in glass, 68 fig., 70–71, 72–73, 73 fig., 76 fig., 84 fig., 173, 178–80, 179 fig., 180 fig. in search of Blaschka matches, 69– 70, 75–79, 84 fig., 85–86 nematodes, 185, 190 threats and conservation status, 81–83, 159 in watercolor, 9–10, 70, 72, 78 fig., 81, 84 fig. Wurtz, Maurizio, 158 Yoon, Carol, 2, 3 zebra slug (Felimare picta), 153, 154 fig. Zimmermann, Carolina, 5
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215
orga n ism s a n d en v iro n m en ts Harry W. Greene, Consulting Editor 1. The View from Bald Hill: Thirty Years in an Arizona Grassland, by Carl E. Bock and Jane H. Bock 2. Tupai: A Field Study of Bornean Treeshrews, by Louise H. Emmons 3. Singing the Turtles to Sea: The Comcáac (Seri) Art and Science of Reptiles, by Gary Paul Nabhan 4. Amphibians and Reptiles of Baja California, Including Its Pacific Islands and the Islands in the Sea of Cortés, by L. Lee Grismer 5. Lizards: Windows to the Evolution of Diversity, by Eric R. Pianka and Laurie J. Vitt 6. American Bison: A Natural History, by Dale F. Lott 7. A Bat Man in the Tropics: Chasing El Duende, by Theodore H. Fleming 8. Twilight of the Mammoths: Ice Age Extinctions and the Rewilding of America, by Paul S. Martin 9. Biology of Gila Monsters and Beaded Lizards, by Daniel D. Beck 10. Lizards in the Evolutionary Tree, by Jonathan B. Losos 11. Grass: In Search of Human Habitat, by Joe C. Truett 12. Evolution’s Wedge: Competition and the Origins of Diversity, by David W. Pfennig and Karin S. Pfennig 13. A Sea of Glass: Searching for the Blaschkas’ Fragile Legacy in an Ocean at Risk, by Drew Harvell
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LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA
Harvell, C. Drew, 1954– author. A sea of glass : searching for the Blaschkas’ fragile legacy in an ocean at risk / Drew Harvell. pages cm. — (Organisms and Environments ; 13) Includes bibliographical references and index. isbn 978-0-520-28568-2 (cloth : alk. paper) isbn 978-0-520-96111-1 (ebook) 1. Marine biodiversity conservation. 2. Marine invertebrates. 3. Marine invertebrates—Models. 4. Glass animals. 5. Blaschka, Leopold, 1822–1895. 6. Blaschka, Rudolf, 1857–1939. I. Title. II. Series: Organisms and environments ; 13. QH91.8.B6H37 2016 333.95'616—dc23 2015029740 Printed in China 24
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