4 August 2018, No3189 New Scientist (Australia) 1401650052, 1401650756

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STRETCHED STARLIGHT

Black hole test proves Einstein right

A QUICK SHARPENER

Light drinking may protect against dementia

RED PLANET BLUES

It won't be so easy to colonise Mars

WEEKLY 4 August 2018 No3189 Australia $9.50 (Inc. GST) New Zealand NZ$9.50 (Inc. GST) Print Post Approved 100007877

IT’S GETTING HOT UP HERE

BECAUSE OF WHAT’S GOING ON DOWN HERE INSIDE DOPE

Does medical cannabis even work?

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Volume 239 No 3189

Insight We’re not equipped to deal with a warming world 18

On the cover

Leaders

14 Stretched starlight Black hole test proves Einstein right 7

6

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MONTAGE: WILLYAM BRADBERRY/SHUTTERSTOCK

Executive chairman Bernard Gray Finance director Jenni Prince Chief technology officer Chris Corderoy Marketing director Jo Adams Human resources Shirley Spencer Non-executive director Louise Rogers

A quick sharpener Light drinking may protect against dementia

3

News 4

THIS WEEK VR helps people who are blind see again. Blame climate change for heatwave. Troubled future for ISS

6

NEWS & TECHNOLOGY We can’t terraform Mars. Biology’s secret shape. AI does Shakespeare. Does alcohol protect against dementia? Tsunami mystery of Stone Age mass graves. Women have more miscarriages than live births. Face recognition helps find you an egg donor. What do chimps get up to at night? Nuclear inspector school. Star stretched by black hole. First new endometriosis drug in a decade

Red Planet blues It won’t be so easy to colonise Mars

24 It’s getting hot up here Because of what’s going on down here 28 Inside dope Does medical cannabis even work? Plus Nuclear inspector school (13). AI does Shakespeare (7). Brexit stockpiling (21). Biology’s secret shape (6)

Debate over medical cannabis is welcome. Extreme weather brings home reality of climate change

16 IN BRIEF Insect sex spree on drugs. Brain parasite linked to entrepreneurship. Self-fixing graphene. Why wounds heal faster in your mouth

Analysis 18 INSIGHT How badly designed buildings make heatwaves worse 20 COMMENT Does Earth Overshoot Day matter? 21 ANALYSIS The scientific guide to stockpiling food for “no-deal” Brexit

Features 24 It’s getting hot up here... We have disrupted the Atlantic’s churn, and that could make future weather even more extreme 28 Inside dope Medical cannabis is sweeping the world, but we are hazy about how it works 38 Robot laws What rules should machines follow when they interact with us? 42 Something in the water Mona Hanna-Attisha risked her career to expose the Flint water poisoning crisis

Culture 44 Through a screen, darkly Why the information age threatens us 45 Way of the whale Earth’s giants are still mysteries to us. PLUS: This week’s cultural picks 46 Nature in a new light There is illumination in dark places

Regulars 22 APERTURE Bob the flamingo 52 LETTERS The world is in for a rough ride 55 OLD SCIENTIST Augusts past 56 FEEDBACK Spontaneously combustible snack 57 THE LAST WORD Mixed leaf salad

4 August 2018 | NewScientist | 1

Humanity will need the equivalent of 2 Earths to support itself by 2030.

People lying down solve anagrams in 10% less time than people standing up.

About 6 in 100 babies (mostly boys) are born with an extra nipple.

60% of us experience ‘inner speech’ where everyday thoughts take a back-and-forth conversational style. We spend 50% of our lives daydreaming.

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Drug science before dogma Moves to legalise medical cannabis stimulate welcome debate

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DURING the cold war, the term “domino effect” was popularised to describe how, if one country succumbed to communism, its neighbours would also topple. It is now being applied to another object of 1950s American paranoia: cannabis. Over the past 22 years, waves of reform have spread across the US, with state after state legalising medical cannabis in one form or another. The UK is the latest domino to topple, or at least shift its position. After a public outcry over two children with severe epilepsy being denied cannabis oil, last week Home Secretary Sajid Javid announced that cannabis-derived

medicinal products will soon be available on prescription. Exactly what this means remains hazy: health authorities have been asked to define what a cannabisderived medicinal product is. The UK has already approved Sativex, an oral spray derived from cannabis plants, for treating muscle spasms in people with multiple sclerosis, although the National Health Service will not pay for it because it is not considered cost-effective. The announcement is welcome progress towards an evidencebased system for regulating cannabis. New Scientist has long argued for such an approach for

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EUROPE swelters. Greece, California and even the Arctic burn. Following record-breaking flooding, Japan is now being hit by a record-breaking heatwave. No one can say we weren’t warned. The reality of humanmade climate change has been apparent for decades to anyone with even a tenuous grip of basic physics and chemistry.

Climate science remains an imperfect science. Researchers have been unable to directly attribute specific weather events to a warming planet even as they build evidence of an overall trend, a reticence seized upon by climate denialists as evidence of uncertainty in the science. No longer. It seems likely that climate change made the current

all drugs. Rigid prohibitionist ideology has not worked. But evidence cuts both ways – and that for the effectiveness of medical cannabis is surprisingly thin (see page 28). At the same time, there are dangers in allowing medical cannabis, not least that it could lead to backdoor legalisation of recreational use without proper debate. But at least we are now having the discussion, which should allow policy to be guided by science rather than dogma. If the tumbling of the medical cannabis domino sets in train a more rational debate across the board, let it fall. ■

European heatwave twice as probable, and that disruption from similar extreme weather is a certainty we must now adapt to (see pages 5 and 18). Less certainly, rumblings of change deep in the north Atlantic Ocean suggest far worse is to come (see page 24). Human-made climate change risks becoming a human tragedy. Those who wilfully deny its reality, or play the fool for the crowd or in defence of vested interests, must be called out. ■ 4 August 2018 | NewScientist | 3

THIS WEEK

Vision restored with virtual reality VR headsets can help people who are blind, finds Catherine de Lange

IRISVISION

A VIRTUAL reality headset has restored sight to people who are legally blind. While it didn’t cure the physical cause of their blindness, the device let people with severe macular degeneration resume activities like reading and gardening – tasks they previously found impossible. Macular degeneration is a common, age-related condition. It affects around 11 million people in the US and around 600,000 people in the UK. Damage to blood vessels causes the central part of the eye, called the macular, to degrade. This leaves people with a blind spot in the centre of their vision, and can make those with the condition legally blind. “You can still see with your periphery, but it’s difficult or impossible to recognise people, to read, to perform everyday experience. “I sensed that I could activities,” says Bob Massof at see again and the tears started Johns Hopkins University in coming,” he says. Maryland. “If I were to look at my wife – The new system, called and I’m standing 4 or 5 feet away – IrisVision, uses VR to make my blind spot is so large I can’t the most of peripheral vision. see her head at all,” says Perski. The user puts on a VR headset But when he uses IrisVision the that holds a Samsung Galaxy magnification causes the blind phone. It records the person’s spot to be relatively much smaller, surroundings and displays so that it no longer covers his them in real time, but the user wife’s whole head, just a small can magnify the image as many part of her face. “If I just move times as they need for their that blind spot I can see her peripheral vision to become “People like that it is an allclear. Doing so also helps to in-one. They read with it, effectively reduce or eliminate watch television, see faces their blind spot. of friends and family” “Everything around the blind spot looks, say, 10 times bigger, so the relative size of the blind whole face and her expression spot looks so much smaller and everything,” he says. that the brain can’t perceive it The software also automatically anymore,” says Tom Perski at focuses on what the person is IrisVision, who also has severe looking at, enabling them to go macular degeneration. from reading a book on their lap When he first started using to looking at the distance without the device it was an emotional adjusting the magnification or 4 | NewScientist | 4 August 2018

Vision of the future: the headset augments your view of the world

zoom manually. Colours are given a boost because many people with macular degeneration have trouble distinguishing them, and users can place a magnification bubble over anything they want to see in even more detail, for example to read small print. In a trial, 30 people used the system for two weeks, filling out questionnaires on their ability to complete daily activities before and after the period. “They can now read, they can watch TV, they can interact with people, they can do gardening. They can do stuff that for years was not even a consideration,” says David Rhew at Samsung Electronics Americas. According to Rhew, the vision of participants was all but restored with the headset. “The baseline rate of vision in the individuals came in at 20/400, which is legally

blind, and with the use of this technology it improved to 20/30, which is pretty close to 20/20 vision,” he says. The results were presented at the Association for Research in Vision and Ophthalmology annual meeting. The headset is now being used in 80 ophthalmology centres around the US, and the next step is to adapt the software to work for other vision disorders. Melissa Chun, at the Stein Eye Institute at the University of California, Los Angeles, is one of those who has been working with the system. “My patients who have used it like that it is an all-in-one. They read with it, watch television, see faces of friends and family,” says Chun, although some have commented that it is heavy for long periods of use. Many people with macular degeneration regularly use eight to 10 different tools, such as telescopes and magnifying glasses, to help them with daily life, but IrisVision can replace them all, says Perski. The system costs $2500, which includes a Samsung Gear VR headset and a Galaxy S7 or S8 smartphone customised with the software. In previous work, Samsung has used the headset to help treat people with chronic pain using immersive virtual reality experiences such as swimming with blue whales or painting. Some of the participants continued to feel the effects up to 48 hours after they stopped using the device. “Maybe down the road we may have to create a VR pharmacy, based on different content for different people with difference conditions,” says Rhew. ■

For new stories every day, visit newscientist.com/news

Climate’s role in heatwave precisely these sorts of events.” “This analysis confirms what we already know – that we are suffering an extreme weather event caused by climate change,” says Gareth Redmond-King, a climate-change specialist at conservation body WWF. The team estimates that similar heatwaves will return. For example, comparable ones will now strike Ireland and the Netherlands every four to seven years in the current climate.

THE current European heatwave was made twice as likely by climate change, according to a preliminary analysis. Temperatures have soared across much of Europe over the past month, regularly exceeding 30°C, and several temperature records have been broken. The conditions have been so extreme that wildfires have broken out in Sweden and the UK. In Greece, the death toll from wildfires at a holiday resort has risen to 91. Elsewhere in the northern hemisphere, firefighters have struggled to control huge wildfires in California. The fires, which began last week, have claimed six lives so far, destroyed more than 500 buildings and triggered the evacuation of 38,000 residents, many from a residential district in Redding (pictured below). And in Japan, record-breaking temperatures have been blamed for more than 100 deaths. Heatwaves are one of the most

“There are many surprises lurking in the greenhouse and they are unlikely to be welcome surprises” “In fact, I think that these sorts of analyses are overly conservative,” says Mann. This summer’s extreme weather in the northern hemisphere is related to the jet stream of air currents being stuck in position. Such patterns have been implicated in “many of the most extreme, persistent summer weather events in recent years”, says Mann.

likely consequences of climate change. As the average global temperature rises because of higher levels of greenhouse gases, more extreme bouts of high temperatures follow. But heatwaves happen anyway. To

In a study published last year, he and his colleagues showed that

find out if the European heatwave was made more likely by climate change, a team at World Weather Attribution partnership led by Friederike Otto of the University of Oxford has conducted a rapid-response study.

have such a heat or higher is generally more than two times higher today than if human activities had not altered climate,” the team reports. The study should be treated with some scepticism because it hasn’t yet been peer-reviewed, says Michael Mann of Pennsylvania State University. “But these findings are consistent with a broader body of work indicating a profound impact of climate change on

JUSTIN SULLIVAN/GETTY IMAGES

They ran climate models with and without our greenhouse gas emissions and tracked how often heatwaves like the current one occurred in both cases. “We estimate that the probability to

ISS end will mean trouble for NASA

such patterns are becoming more common as a result of human-caused climate change (Scientific Reports,

THE International Space Station (ISS) is nearing its expiry date, but NASA isn’t ready.

doi.org/f9vwxh). “Events like the massive wildfires breaking out around the Arctic circle really have no precedent in modern history,” says Mann. “It is a reminder that there are many surprises lurking in the greenhouse and they are unlikely to be welcome surprises.” Meanwhile,farmers have warned

The US plans to stop funding the ISS in 2024, leaving its future uncertain. But without it, NASA won’t be able to study the health risks of spaceflight or test technology that will enable deep-space exploration.

of impacts on harvests following the UK heatwave. Many parts of England and Wales have seen little or no rain since May, and despite thunderstorms breaking the heatwave last weekend, many crops remain in drought conditions, including those needed as animal feed. The National Farmers’ Union has planned an emergency summit on 1 August to address this crisis. “It’s a timely reminder that we shouldn’t take food production for granted,” says NFU president Minette Batters. ■

Read more: Leader (page 3); designing buildings for the heat (page 18); why ocean systems could cause future heatwaves (page 24).

A report from NASA’s Office of Inspector General predicts that at least 10 ongoing studies won’t be completed before the end of the ISS. These include research into how vision and motor functions degrade in microgravity, risks of cognitive and behavioural problems, and long-term life support in space. NASA is working on plans to complete these studies without the ISS, including doing some tests on the ground. Part of the reason to get rid of the ISS is to free up funds for NASA to go to Mars, but without this essential research, such a trip won’t be possible.

Gene-edited food classed as GMO IF A plant or animal’s DNA has been deliberately altered, including by CRISPR gene editing, it should be subject to the European Union laws governing genetically modified organisms, the European Court of Justice ruled last week. The decision has delighted a few environmental activists, but dismayed those involved in plant breeding and research, as it will make it far more difficult and expensive to introduce varieties of gene-edited crops. The plants we eat today are genetically different to their ancestors. Starting in the 1950s, many were created by zapping cells with X-rays to induce thousands of random, unknown mutations. However, the EU laws specifically exclude this crude method, meaning crops created this way won’t count as GM – only those created by newer, more precise methods. 4 August 2018 | NewScientist | 5

NEWS & TECHNOLOGY

University used results from several spacecraft to figure out whether moving all of Mars’s CO2 from the ground into the atmosphere would create high enough temperatures and pressures for life. Right now, Mars has an atmospheric pressure of about 6 millibars – tiny compared with the 1 bar at sea level on Earth. “We would need something like a million ice cubes of CO2 ice that are a thousand kilometres across in order to get to 1 bar,” says Jakosky. At 1 bar, the temperature would be just above 0°C, allowing

WE HAVE long dreamed of turning Mars into a second Earth, a place where humans could live without having to put on spacesuits. The easiest way to do that would be to use the carbon dioxide already on Mars to create a new atmosphere, but now that seems to be impossible. Terraforming Mars to make its surface habitable for Earth life would involve raising both its surface temperature and pressure by adding an atmosphere made of heat-trapping greenhouse gases. The only ones present on “We know how to warm up Mars in large quantities are CO2 a planet – we’re doing it on and water vapour, both frozen. Earth. But is there enough “If there is enough CO2, we could warm up Mars in 100 years once carbon dioxide on Mars?” we start,” says Chris McKay at NASA’s Ames Research Center in liquid water, and thus life, on the California. “We know how to warm surface. The atmosphere wouldn’t up a planet – we’re doing it on be breathable, but humans could Earth. The fundamental question get by with breathing masks, not is, ‘Is there enough stuff?’” full spacesuits. No, it turns out. Bruce Jakosky But Jakosky and Edwards at the University of Colorado, found that there is probably only Boulder, and Christopher enough CO2 in the Martian polar ice caps, dust and rocks to raise Edwards at Northern Arizona

Complex new shape found hidden in cells

We had assumed that these cells adopted prism- or pyramid-like shapes to make such complex structures. But now Luis Escudero of the University of Seville in Spain and his colleagues have modelled curved

The Red Planet is too cold and airless for us to inhabit at present

The newly discovered scutoid shape explains how cells are packed together in nature

a particular prism-like shape with five

a fishing expedition – there’s no guarantee that these things exist.” There is another factor at play, too – we also need nitrogen, and we don’t know how much Mars has. “If there’s not enough CO2, terraforming would take thousands of years or more, but it’s still possible,” says McKay. “If there’s not enough nitrogen, you need Star Trek. You need warp drive and tractor beams, you need to pull nitrogen from the atmosphere of Jupiter. It becomes science fiction.” ■

edges at one end, and six at the other, and with one of the side edges divided into a Y shape (see diagram). These scutoids slot neatly together (Nature

surfaces that have very different

Communications, doi.org/gdvqc6). The team also identified scutoids in zebrafish tissues, and

areas at their top and bottom.

a preliminary check found them in

In particular, the team wanted to explain a strange finding from

mammalian cells too, indicating that

SAY hello to the scutoid, a new shape that has been discovered in our cells. This addition to geometry explains how nature packs cells efficiently into three-dimensional structures. All animals are formed from

tissues where the cells have to “pave”

tissues that bend into complex shapes. The building blocks of these structures are epithelial cells, which pack tightly together to form the lining of blood vessels and organs.

epithelial cells can have different

6 | NewScientist | 4 August 2018

the pressure to 20 millibars. So we can’t terraform Mars with existing technology (Nature Astronomy, doi.org/csk4). “It’s not that terraforming itself isn’t possible, it’s just that it’s not as easy as some people are currently saying,” says Jakosky. “We can’t just explode a few nukes over the ice caps.” There may be hidden reservoirs of carbon deep under the surface that could make the job easier, says Robin Wordsworth at Harvard University. “If you could develop the technology to look for those and extract it, that might get you close to the bar,” he says. “But it’d be kind of

previous research showing that types of neighbours at their top and bottom surfaces. The modelling showed that the only way to achieve this pattern was for the cells to adopt

+ SOURCE: NATURE COMMUNICATIONS

Leah Crane

MARK GARLICK/SPL/GETTY

Plan to terraform Mars is out of gas

they are widely used by nature. The discovery has important implications for tissue engineering and the creation of artificial organs, which rely on understanding and mimicking the 3D organisation of cells. Alison George ■

For daily news stories, visit newscientist.com/news

AI poet learns by copying Shakespeare

Sonnets come in many different variations but they always have 14 lines and usually include a regular rhyme scheme of some sort. Shakespeare pioneered his own version in which the lines were divided into three verses (or stanzas) of four lines (quatrains), finished with a rhyming couplet. A team led by Jey Han Lau at IBM Research Australia decided to use deep learning, a type of artificial intelligence, to generate sonnets. The AI was trained on data from 2600 or so sonnets — around 367,000 words in total — taken from a free online database of out-of-copyright books called Project Gutenberg. The AI generated its own Shakespearean sonnet quatrains by first selecting a rhyming pattern and then generating one word at a time until it had completed a verse (arxiv. org/abs/1807.03491). When the team asked workers from a crowdsourcing website to rate the generated poems, they were unable to distinguish them from the real deal because of their strict adherence to rhyme and meter – but the oftennonsensical content meant that poetry experts were not so easily fooled. Poet and broadcaster Michael Symmons Roberts says the AIgenerated sonnets do not come close to the “richness or complexity” of Shakespeare. And he points out that the AI wasn’t able to emulate the “interweaving networks of meaning and emotion and beauty and purpose that make a poem”. “At the moment, intriguing as it is, Shakespeare wins it by a country mile,” he says. A selection of the AI’s best verses can be found at newscientist.com/ AI-shakespeare. Niall Firth ■

GRETA RYBUS/PLAINPICTURE

SHALL I compare thee to a summer’s day? It’s one of the most famous opening lines in poetry and comes from one of Shakespeare’s bestknown sonnets. Now artificial intelligence is trying to come up with its own version of the form.

A few drinks might help stave off dementia LIGHT drinking helps prevent dementia, total abstention from dementia, and now we may know alcohol carries a slightly higher why: it revs up the brain’s waste risk than low to moderate disposal system. drinking. But it was unclear why. Brain cells are surrounded The reason may be the brain’s by a network of ultra-thin tubes waste disposal system, known as that flush toxins and cell waste the glymphatic system, which was products away. Work in mice only discovered in 2012. We know shows that low levels of alcohol it ramps up its activity during stimulate this system, while sleep. Among the toxins it clears higher amounts hinder it. is a protein called beta-amyloid, If the findings apply to people, which makes up the sticky the low levels would be equivalent “Abstention from alcohol to about two units of alcohol causes a slightly higher a day, which is about a pint of risk of dementia than low beer or a medium glass of wine. to moderate drinking” Alcohol has been getting a bad press lately. Excessive drinking causes liver damage plaques found in the brains of and has been linked with several people with Alzheimer’s disease. kinds of cancer. In the UK, the Some studies have suggested recommendation for how much it that long-term sleep disruption is safe to drink has been cut, with may contribute to Alzheimer’s both men and women advised to by causing amyloid build-up. stick to 14 units or fewer a week. Iben Lundgaard of the The latest UK government report University of Rochester in New said even drinking at very low York and her colleagues looked levels carries some risk. However, at the effects of alcohol on this this relates to a slightly higher network, by injecting a dye into rate of cancers that are fairly rare – mouse brains then removing such as those of the oesophagus. them half an hour later to see When it comes to more how much had got into the tubes. common conditions, such as Low doses of alcohol boosted

Here’s to our health! A little bit of alcohol could be good for the brain

the amount cleared by 40 per cent compared with mice that had no alcohol. Intermediate and high doses had the opposite effect, cutting it by about 30 per cent. It is unclear how much that would affect people’s risk of Alzheimer’s. Roxana Carare of the University of Southampton, UK, says that the reason a low dose of alcohol has this effect may be because it raises the heart rate, and the pumping of blood helps drive fluid through the glymphatic system. “But there’s a lot we still don’t know about the normal functioning of the glymph system. We don’t know how this translates to humans.” At the Federation of European Neuroscience Societies meeting in Berlin last month, Lundgaard said that light drinking does seem to benefit the glymph system, but that more data would be needed before people make decisions about how much they drink based on this work, especially as it was in mice: “I think that would be a little bit too soon.” Lundgaard says that as well as considering how alcohol affects their risk of Alzheimer’s, people might also want to consider the effect on cancer. Clare Wilson ■ 4 August 2018 | NewScientist | 7

NEWS & TECHNOLOGY Miscarriage rate much higher than assumed MOST fertilised eggs miscarry rather than developing into healthy babies. However, most miscarriages usually occur very early in pregnancy, without a woman even being aware she was pregnant. A few previous studies have suggested that miscarriages are the most common outcome of conception. Now a meta-analysis claims to have JIM RICHARDSON/GETTY

“unambiguously” confirmed it. For women in their 20s, conception is as likely to end in miscarriage as it is in a live birth, says William Rice, an evolutionary biologist at the University of California, Santa Barbara. “It is not an abnormality,”

Tsunami mystery of Stone Age graves Michael Marshall

STONE AGE mass graves on UK islands might be filled with the victims of a prehistoric tsunami, according to a controversial new study. Orkney and Shetland are archipelagos that lie off the north coast of Great Britain. Both have been inhabited for thousands of years; Orkney is home to prehistoric villages including Skara Brae, while Shetland boasts Jarlshof, among others. There are many stone cairns on Orkney, containing multiple graves, including one that may hold more than 300 bodies. Cairns are also found on Shetland but they are less well-preserved. Most archaeologists think the cairns are a sign of religious practices, or that they had a social function such as asserting ownership over land. But Genevieve Cain at the University of Oxford and her colleagues have an alternative suggestion: that 8 | NewScientist | 4 August 2018

some, at least, are the mass graves of tsunami victims. Tsunamis occur in the seas around the UK, albeit rarely. Cain and her colleagues focused on one that happened about 5500 years ago. Geological evidence from Garth in Shetland suggests the sea rose by 10 metres, enough to swamp coastal communities. In the face of such a disaster, bodies must have been buried hastily in mass graves. “There are many mass burial sites and their ages at least

“There are many mass burial sites and their ages approximate to a tsunami 5500 years ago” approximate to the timing of the Garth tsunami,” says Cain. “This has never been proposed as a cause, largely because the sites were not studied with this in mind.” Cain admits the link is speculative and wants to look for marine microorganisms called

If a tsunami did hit Orkney it would have inundated coastal villages

he says. “It’s the norm.” The rate shoots up as women age, with women in their late 40s having

diatoms that enter the blood and then bone marrow of people who have drowned in seawater (Journal of Archaeological Method and Theory, doi.org/csmd). “If it did inundate Shetland and Orkney as we think, then it probably affected the majority of the coastal communities – and to be honest, most of the communities in the islands are coastal,” says co-author James Goff at the University of New South Wales, Australia. Other archaeologists are intrigued but sceptical. “The architecture of the tombs themselves does nothing to suggest anything carried out in haste,” says Rebecca Crozier at the University of Aberdeen, UK. “They are sophisticated and complex structures, indicative of careful planning.” “I would be extremely cautious,” says Alasdair Whittle of Cardiff University in the UK. He accepts that coastal mass graves elsewhere, especially in the Pacific, could hold prehistoric tsunami victims, but isn’t yet convinced by the evidence on Orkney and Shetland. ■

more than 30 miscarriages per newborn. “It starts high and it gets extremely high,” says Rice. He combined data from a number of sources to work out the frequency of all miscarriages, including the very early miscarriages that women aren’t usually aware of. For instance, IVF records reveal how many live births result per embryo implanted. Other studies have looked at how the rate of lethal chromosomal abnormalities in eggs rises as women age. For example, women in Denmark, who have free access to birth control and elective abortions up to 12 weeks, have 1.7 children on average. These women have 2.1 miscarriages in their lifetime on average, Rice calculates, along with 0.4 elective abortions (bioRxiv, doi.org/csmg). There is no doubt that miscarriages are common and that in most cases women don’t know they have occurred, says Ruth Bender Atik, director of the Miscarriage Association in the UK. “I do think it would be enormously helpful if there were more education and thus awareness that it can take time to conceive and that many pregnancies do end in miscarriage,” she says. “That often comes as a shock.” Michael Le Page ■

NEWS & TECHNOLOGY

Egg donors paired by face recognition

photograph of the donor when they donate an egg. An algorithm analyses their face and records key features in an encrypted database. A prospective parent can take a picture of themselves with a smartphone or tablet, and see how many available egg donations are from women who match their appearance. The system took a year to develop, says Yus, the bulk of which involved creating a

face-matching algorithm. For some people, having a child who closely resembles them is an important part of starting a family. Selma from London, who wished to keep her surname anonymous, turned to egg donation after undergoing three unsuccessful cycles of IVF with her own eggs. Although her UK clinician is able to see photos of the donor, she is not. “Already the thought of you using someone else’s egg is impersonal, even though you’re carrying it, you think I’m carrying someone else’s child,” she says. Selma didn’t use Ovobank’s service, but says that using face-matching technology to get a stronger physical resemblance could make her feel closer to a child. The service has good science behind it, says Peter Claes at the Catholic University of Leuven (KUL) in Belgium. “We can see a lot of genetic information from faces,” he says. The forehead, eyes, nose and chin are all under strong genetic control, says Claes. So a baby from an egg donated by someone with similar facial features to the recipient is more likely to resemble the recipient. However, the likelihood of getting a close match will depend on the size of the database, he says. The bigger it is, the more likely you are to find someone similar. ■

a very beautiful service”. Ovobank announced the facematching service at the European Society of Human Reproduction and Embryology annual meeting in Barcelona, earlier this month. It has launched the service in two clinics, in Barcelona and Marbella. The system works by taking a

Eggs from similar-looking donors produce similar-looking babies

Chimps are busy at night but we don’t know why

evening and the following morning

doing,” says McCarthy. “It could be

but McCarthy says it could be much

has largely been a mystery.” However,

they were travelling to feeding sites

more. For one thing, the cameras will

in 2014 it emerged that chimps in

and feeding in the night, or it could

Uganda raid farmers’ crops at night.

be they were changing from one nest

have missed activity up in the trees. A study published in February

McCarthy and her colleagues compiled data from 22 chimp study

location to another.” Lone males were

found that chimps in Fongoli,

the most frequently observed. “It

Senegal, were most active when the

THE chimpanzees are up to something. A large study suggests a lot of them are active at night, but it can’t tell us why. Chimps’ nocturnal behaviours have

sites in Africa, and used ground-based

could be males either doing patrolling

moon was out and during the dry

camera traps to try to see what the

behaviours, or seeking out mating

season – perhaps feeding at night

animals were up to. The traps spotted chimps out and about at night at 18 of the 22 sites.

opportunities,” she says. About 2 per cent of the chimps’ recorded activity took place at night,

rather than in the heat of the day. McCarthy and her colleagues were surprised to find that chimps were

barely been studied, says Maureen McCarthy of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany. “What happens between the time they nest in the

It happened at all hours of the night,

AN EGG bank in Spain is using face-recognition technology to match prospective parents with donors who look like them. The idea is that mothers get a child who resembles them even though they aren’t genetically related. Egg donation is relatively common in Spain compared with in other European nations. The country has strict laws protecting the anonymity of the donor, and is a popular destination for women across Europe seeking eggs for IVF. Basic physical characteristics such as ethnicity, hair colour and eye colour are recorded at the time of donation, but this still leaves a lot to the imagination. So Spanish company Ovobank is using face-recognition algorithms to match prospective mothers with donor eggs. Its service provides a score of how much the donor looks like the mother, says Ana Yus Castan at Ovobank, who created the service with her husband following her own experience of IVF. “Patients stress about the resemblance of the child,” says Yus. “So for us it is

10 | NewScientist | 4 August 2018

SCIENCE PHOTO LIBRARY/ZEPHYR/GETTY

Frank Swain

but was most common at twilight. In most cases, the chimps were simply snapped moving past the camera. “We don’t know what they were

more active at night in areas with few

“What happens between the time chimps nest and the following morning has largely been a mystery”

humans. Many animals are becoming more nocturnal to avoid encounters with humans, but chimps buck that trend. Michael Marshall ■

NEW SCIENTIST DgS CO VE RY

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WHAT IF TIME STARTED FLOWING BACKWARDS?

WHAT IF THE RUSSIANS GOT TO THE MOON

FIRST?

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NEWS & TECHNOLOGY FIELD NOTES Los Alamos National Laboratory

working with plutonium. Geist reassured us we were safe. After a morning of lectures, we went into the lab. First up was detecting gamma rays. “Gamma rays are like a fingerprint. They can uniquely identify a material,” said Ram Venkataraman, one of the instructors from Oak Ridge National Laboratory, Tennessee. I saw what he meant when we placed a sample of cobalt-60 in front of a sodium-iodide detector and mountains of red bars took over the computer screen. The peaks and valleys represented the energy levels of the X-rays and gamma rays emanating from the sample. Each radioactive isotope has a distinct readout. The cobalt-60 samples we used were contained in nested boxes. The biggest was a small plastic container with a blue lid, the kind you might use to store salad dressing. Within that was a smaller plastic box and inside that was a coin of metal. At its centre, a dot of cobalt was barely visible.

Chelsea Whyte

IT WAS a blisteringly hot morning when I reported to Los Alamos National Laboratory for nuclear inspector school. The lab is the old home of the Manhattan Project, the secret effort to develop the first nuclear weapons. It sits atop a plateau north of Santa Fe, New Mexico, isolated by geography and security checkpoints. I was driven down “Plutonium Corridor”, a main road that passes a building encased in five layers of barbed wire fencing where they

“I had to stick to a few strict rules: no phones, no computers and no touching the plutonium”

Handheld detectors can track down radioactive materials like uranium

LOS ALAMOS NATIONAL LABORATORY

design and maintain nuclear bombs. Elsewhere, the lab trains international inspectors to detect plutonium and enriched uranium – the hallmarks of a nuclear weapons programme. The increasing fears over North Korea and Iran developing the bomb show why such lessons are needed. One goal is to build partnerships with countries as they start to use nuclear power, instead of trying to police a nuclear programme that has run unchecked for years, says Danielle Watts at the US National Nuclear Security Administration. I had been invited to join the training session for two days, provided I stick to a few strict rules: no phones, no computers and no touching the plutonium. Our host, Bill Geist, started by handing out dosimeters to track any radiation we received. Some of the students immediately seemed concerned – it brought home that we were going to be

LOS ALAMOS NATIONAL LABORATORY

Hunting potential nuclear bombs

Then things got serious. Our instructor, Robert WeinmannSmith, pulled out a metal canister about the size of a paint can with a makeshift handle of yellow duct tape. “Let’s measure plutonium,” he said, setting it on the table with a loud clank. The sample emitted so many X-rays that it overloaded the detector, so we had to add shielding to reduce the intensity. Finally, we had a mystery sample, simply marked “NUCLEAR MATERIAL”. Studying the pattern of gamma radiation, we cracked it: uranium. The next day we were given handheld detectors, which show a red bar that grows as you get closer to a radioactive source.

Los Alamos was the birthplace of nuclear weapons

We pointed them under chairs and behind computers until we found something radioactive in a desk drawer. Figuring out what was inside proved difficult because it was a mixture of several materials: sodium, thorium and caesium. The radiation given off by a combination of fairly innocuous materials can look like plutonium or uranium to the untrained eye. We also learned to determine how enriched a sample of uranium is and calculate the mass of nuclear material inside a sealed container. That is an important skill, because people attempting to make a bomb could skim off a small amount from each canister at a nuclear fuel plant. At times, piecing all this together felt like a game of Cluedo: which isotope, how much of it, and how enriched is it? But then I would remember what Weinmann-Smith told me: there is at least enough nuclear material in the world to make 200,000 bombs, and the International Atomic Energy Agency speculates that 30 countries have the capability to do so. Given the current climate, this work is deadly serious. ■ 4 August 2018 | NewScientist | 13

NEWS & TECHNOLOGY Endometriosis drug approved in the US A PILL for treating endometriosisrelated pain will soon be available in the US after being approved by the US Food and Drug Administration. Endometriosis occurs when tissue from the uterus spreads to other parts of the body, usually within the pelvis. It can cause severe pelvic pain during menstruation and sex, or all the time, and affects up to one in 10 women ESO/M. KORNMESSER

before they reach menopause. Endometriosis-related pain is normally managed with painkillers, contraceptives that shorten or suppress menstruation, or injectable hormone treatments.

Starlight stretched by black hole Sarah Leach

that don’t exist in other places. The team spent 10 years observing S2 before it made a close approach to the black hole in 2002. But the telescope available at the time limited what they could learn from it. They knew the star would pass just as close 16 years later, in May 2018, and started planning an upgrade. In the end, they used four telescopes in Chile to give them

A STAR hurtling towards the supermassive black hole at the centre of the Milky Way has helped astronomers test Albert Einstein’s theory of general relativity, showing that it holds up even under some of the most extreme conditions found within our galaxy. For a long time, astronomers at the European Southern “General relativity holds up Observatory in Germany have even under some of the had their equipment trained on most extreme conditions a star very near Sagittarius A*, found within our galaxy” the supermassive black hole at the centre of our galaxy. The star, called S2, passes less than 20 the equivalent of a 120-metre million kilometres from the black diameter telescope, powerful hole, or about four times further enough to see objects on the than Neptune is from the sun. moon just centimetres across. “The galactic centre is an ideal When the team observed the laboratory,” says team member star passing close to the black hole Reinhard Genzel of the Max again, they were able to carefully Planck Institute for Extraterrestrial measure its light and found a Physics in Germany. This is change in its colour as it moved. because the extreme gravity This alone wouldn’t be too creates a perfect opportunity to exciting. Objects often change see effects of general relativity colour in space, through 14 | NewScientist | 4 August 2018

Albert Einstein predicted that stars would turn red near black holes

For many women with the condition, these treatments either don’t work, trigger side effects like

something known as the Doppler effect. Anything moving towards an observer has its light waves squished together, making them shorter and therefore bluer. Objects moving away, however, have their light stretched a bit to longer, redder wavelengths. But in this case the team found that the gravitational pull of the black hole was responsible (Astronomy & Astrophysics, doi. org/cshv). This gravitational red shift occurs when the waves of light from an object are stretched by the gravity of another object. “Gravitational red shift is a core element of general relativity,” says Feryal Ozel of Arizona State University. “It has been previously measured for the sun, nearby stars and white dwarfs, but it is the first time we see it from an object so far away in the galaxy and one that is orbiting a black hole.” In this case, the red shift was exactly as predicted by general relativity. However, the researchers point out that this doesn’t mean relativity is absolutely correct. “We know Einstein’s theory must break down at very small scales and extreme conditions around the universe,” says Genzel. ■

weight gain or mood swings, or can only be taken for short periods due to their effect on bone density. The newly approved drug, elagolix, can be taken for longer, but still has side effects. In a placebo-controlled clinical trial involving almost 900 women with moderate to severe endometriosis pain, elagolix reduced menstrual pain in over 40 per cent of women and non-menstrual pelvic pain in over 50 per cent when taken as a once-daily pill. Participants also reported lower average pain during sex. The drug works by reducing oestrogen, the hormone that drives endometriosis. Because it only lowers oestrogen slightly, it can be taken for up to two years. In contrast, more powerful injectable hormone treatments can only be taken for six months because they cause bone loss. The trial found that elagolix was associated with several side effects including hot flushes and headaches in about 20 per cent of women, and nausea in about 10 per cent. Any extra options for treating endometriosis are welcome, says Elizabeth Farrell at women’s health organisation Jean Hailes in Australia. However, at a cost of $845 per month, elagolix is unlikely to be a first-line treatment, she says. Alice Klein ■

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IN BRIEF Graphene’s latest trick? Fixing itself

Water, water, everywhere, but just a drop of wilderness left

included, too, because it can affect coastal habitats.

THE ocean is barely wild anymore. A map of ocean wildernesses shows that only 13 per cent of global waters remain undisturbed by human activity.

Of the 16 ocean realms the team studied, the surface waters with the largest portion of wilderness left are parts of the Southern Ocean closest to Antarctica, which are 88.5 per cent wilderness. Arctic waters are also less disrupted than other areas, although both may soon change as the loss of sea ice increases, says Jones.

Kendall Jones at the University of Queensland in Australia and his colleagues analysed the effects of 19 human stressors on the seas, which fall into four broad categories: fishing, pollution, climate change and shipping. Transporting vast quantities of goods across the ocean can disturb habitats, pollute the water and move invasive species around. And pollution doesn’t just include physical contaminants – light pollution is

In the temperate areas of the Atlantic – between Europe and North America, and between Africa and South America – wilderness is almost entirely gone, with less than 0.5 per cent of waters undisturbed. Two-thirds of all the ocean wilderness is in international waters. And of that left in coastal areas and the open seas, Jones found that less than 5 per cent is protected (Current Biology, doi.org/csh5).

Woes of a half-male, half-female cricket AN EXTREMELY rare cricket with female sex organs but male wings is giving biologists insights into sexual behaviour. Gynandromorphs are creatures that possess both male and female characteristics. Kazuhiro Tanaka at the Miyagi Gakuin Women’s University in Sendai, Japan, and his team caught the unusual lawn ground cricket (Polionemobius mikado) east of Tokyo. 16 | NewScientist | 4 August 2018

They found it had wings like those of a male and the egg-laying organ of a female. The researchers wanted to see whether it behaved more like a male or female. Male crickets make chirps with their wings to attract receptive females, during sex and to repel other males. But Tanaka says that in laboratory containers, the gynandromorph tried to chirp but couldn’t make a sound. It still

tried to serenade females put in its container, but they didn’t let it get too close. Male crickets seemed to take a liking to the gynandromorph and one even tried to deposit a sperm package. But the gynandromorph tried to chirp aggressively at the males, and bit one (Entomological Science, doi.org/csj3). Tanaka says such organisms offer opportunities to study the molecular mechanisms of sex determination or sex behaviour.

OFTEN hailed as a miracle material, graphene, an atom-thick layer of carbon, now comes in a self-healing version. Hongwei Zhu at Tsinghua University in China and his colleagues have made a graphene gel that is tough and rigid when dry, but squidgy, stretchy and self-healing when wet. They mixed graphene sheets with water, then added polyacrylic acid, which has good water-absorbing properties, and then calcium carbonate. The result is a stable gel. It dries into a hard, plastic-like substance, strengthened by the graphene, and can be formed into a solid shape, a thin film or a foam, all with potential applications, Zhu says. When the team cut a piece in half and placed the halves back together, they fused easily. Eventually, Zhu says, it could be used to make a robot that can heal itself (Advanced Materials, doi.org/gdtc47).

Mouths primed to heal wounds fast IT IS true – wounds in the mouth really do mend much faster than cuts to the skin. A study has found that cells in the mouth are always primed for healing, a result that could hint at ways to improve wound-healing elsewhere. J.Silvio Gutkind at the University of California, San Diego, and his team made small wounds in the mouths and on the upper arms of 30 volunteers. The oral damage healed about 5 to 10 times faster. Biopsies revealed networks of healing genes are permanently active or on standby in the cells of the mouth lining, but not in skin cells. When the team altered mice to activate these networks in skin, external wounds healed faster (Science Translational Medicine, doi.org/cshs).

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CASTRATION and then involuntary simulated chemsex. That’s the fate that awaits cicadas infected by the Massospora fungus, according to researchers who discovered psychoactive compounds in fungal growths in the stricken insects. Massospora infections in cicadas are associated with “hypersexual” activity, including cases in which, for example, males suddenly attempt to mate with other males. This appears to help spread the fungus. But the fungus makes these forays a miserable venture. When infected cicadas first try to mate, the end of their abdomens, including genitalia, are often pulled off. This abdominal mass is replaced by a large fungal “plug” (the white part of the cicada in the image below). Matt Kasson at West Virginia University and his colleagues looked at 56 plugs and found that about half contained either an amphetamine, or psilocybin or psilocin, the active ingredients of magic mushrooms (bioRxiv, doi.org/csk2). It isn’t clear exactly what function these chemicals play, but it is plausible that they help improve the insects’ endurance as they embark on fungus-fuelled sex, says Charissa de Bekker at the University of Central Florida. She and her colleagues have shown that Ophiocordyceps fungal infections

DOUG WECHSLER/NATUREPL

in ants secrete LSD-like compounds.

Entrepreneurial spirit more likely if you have cat parasite STUDENTS in the US who have a type of brain parasite carried by cats are more likely to be majoring in business studies. The pets are hosts for the protozoan parasite Toxoplasma gondii. It can infect people through contact with cat faeces, contaminated water or poorly cooked meat from infected livestock. As many as one-third of the world’s population may have it. The parasite doesn’t usually make us feel sick, but it forms cysts in the brain where it can remain for the rest of a person’s

life. Some studies have linked infection with slower reaction times, bipolar disorder, schizophrenia, suicidal behaviour and explosive anger. Now an analysis of almost 1300 US students has found that those who had been exposed to the parasite were 1.7 times more likely to be doing a business major. In particular, they were more likely to be focusing on management and entrepreneurship than other business-related areas. The study also found that professionals attending business

events were almost twice as likely to have started their own business if they were T. gondii positive, and that countries with a higher prevalence of the infection show more entrepreneurial activity. The team behind the study say their results suggests that the parasite may be involved in reducing a person’s fear of failure and high-risk, high-reward ventures. Rodents infected with T. gondii are known to become less fearful of encountering cats (Proceedings of the Royal Society B, doi.org/csh7). HIROSHI ISHIGURO LABORATORY, ATR

Sex-mad cicadas are on drugs

Blockchain can tell if cannabis is legit THE software behind the bitcoin cryptocurrency has found an unlikely use – spotting counterfeit drugs. Using edible barcodes and a blockchain, TruTag Technologies in Hawaii believes it can track cannabis sold legally in the US (for more on the topic see page 28). The firm tags cannabis edibles, such as brownies or lollipops, with silica particles described as edible barcodes. The idea is that these barcodes are very difficult to imitate and can be scanned to reveal if a product is legitimate. Similar tags have been used for medication since 2016. The tags are created by etching a thin silicon wafer with a pattern of tiny holes. The wafer is ground into microscopic particles that retain the code, and these are attached to the surface of the cannabis. Anyone can then read the codes with a handheld scanner and check them online. The online portion of the system is a blockchain-based database developed by Tag-It Tech, based in Seattle. Blockchain is a form of digital ledger originally developed for cryptocurrencies that can publicly record information in a way that is difficult to tamper with.

Ever felt a third arm might be handy? EIGHT people have reliably used a mind-controlled robotic arm at the same time as their own arms, letting them do two things at once. Participants in the experiment

to move a ball around on a tray. The team at the Advanced

to pick up on the differences in brain patterns when participants imagined it grasping and releasing a bottle.

Telecommunications Research Institute International in Kyoto, Japan, found that eight out of the 15 participants could reliably roll the ball to target points on the tray while grasping and releasing the bottle with the robotic arm, but the rest were only successful about half the time (Science Robotics, doi.org/csht). Robotic arms like this could be

To test their skills, volunteers had to perform two tasks simultaneously: hold and release a bottle using the robotic arm and use their real arms

useful for people who work in factories, for example, by helping to lift heavy objects or just providing an extra hand when needed.

had to learn to control a robotic arm using a brain-machine interface with electrodes on their head to capture brain activity. The arm was calibrated

4 August | NewScientist | 17

INSIGHT SURVIVING THE HEAT

We must build for a warmer future Badly designed homes make heatwaves worse, says Michael Le Page

TEMPERATURES have been soaring in much of the northern hemisphere recently (see page 5). In southern parts of the UK, they have been pushing 30°C for weeks, and health warnings about the heatwave have been flying. That has attracted some derision from those living in hotter places, such as the city of Darwin in Australia. “In Darwin that’s called winter,” was one mocking response. Yes, it gets much hotter elsewhere. But hot places are geared up to cope with heat. By contrast, when temperatures soar in normally cooler cities like London, people commute on crowded trains that breach temperature limits for transporting livestock, work in buildings with limited cooling systems and struggle to sleep in stuffy houses designed for cold winters. Hot summers will soon be the norm in temperature climes because of climate change. So unless more is done to adapt buildings and transport systems to the heat, summers are going to become ever more miserable for millions – and ever more deadly to young, ill and old people.

RICHARD BAKER/GETTY

Preventable deaths

Glass skyscrapers such as London’s “WalkieTalkie” are ill-adapted for climate change

18 | NewScientist | 4 August 2018

“Without further action, the number of heat-related deaths could increase from 2000 per year today to 7000 in the 2050s,” says Kathryn Brown, head of adaptation at the UK Committee on Climate Change. If a flood killed that many people, there would be a massive outcry, says Bob Ward of the Grantham Research Institute on Climate Change in the UK. “It’s a scandal that hundreds of people are dying,” he says. “Many of those are preventable deaths.” A report published last week by the UK’s Environmental Audit Committee says the problem is so serious that the country should have a dedicated government minister to tackle the issue. But what can be done?

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Countries like the UK are simply not doing enough to fix buildings that are poorly designed for staying cool in hot summers. Worse still, new buildings are being designed in such a way that they require vast amounts of energy to cool. It is more than just a matter of comfort. High temperatures reduce the productivity of workers and affect how well children learn, lowering exam scores with potentially life-long impacts. Countries must do three things to protect their citizens’ lives and livelihoods. First, existing infrastructure – from homes and hospitals to schools, offices and trains – needs to be modified to cope with the extremes expected as the planet warms, including longer and hotter heatwaves. Second, new buildings and transport systems need to be designed with future heatwaves in mind. Third, cities as a whole need to minimise the “urban heat island” effect that can boost local temperatures by several degrees. We can keep buildings cool by actively removing excess heat – air conditioning, in other words. We can also stop them getting too hot in the first place. Needless to say, prevention is better than cure. The problem with air conditioning is that it produces yet more heat. A study in Paris concluded that air conditioning could warm the city by as much as an extra 2°C. It is also expensive to install and run, because air conditioners use a lot of energy. In fact, 10 per cent of electricity globally is used to power air conditioners and this is expected to soar as the world gets hotter and more people can afford air con, according to a recent International Energy Agency report. That is a huge problem, because most electricity is still generated from fossil fuels. In other words, the more air conditioning we use, the hotter the planet will become. The focus, then, should be on creating buildings that can stay warm in winter and cool in summer. Architects and planners

Building smarter homes would help people living at mid- and high-latitudes to keep cool without energy-intensive air conditioning Cool shades Eaves, balconies, shutters and awnings block the sun

SUMMER SUN

Easy on the glass Minimises heat gain in summer and heat loss in winter

WINTER SUN Cubism Buildings with this shape are slow to warm up in summer and retain heat in winter

Thermal mass Thick walls and solid loors slow warming during heat of the day

don’t seem to have realised this, Designer homes often feature says eco-designer Sue Roaf, wall-to-ceiling windows, and most co-author of the book Adapting new office buildings are all-glass Buildings and Cities for Climate skyscrapers with no shading and Change. “They just don’t get it.” sealed windows. Current architectural crazes Glass is very energy inefficient – are for lightweight glass buildings it leaks heat in the winter, and that would become unbearably soaks it up in the summer. The hot without energy-intensive air bottom line is that people who conditioning systems. Roaf lives live in a warming world should in an eco-house with a much more not build glass houses. “It’s a sensible approach. no-brainer,” says Roaf. The first step is to think about the shape of the building, and the “The bottom line is that people who live in a size and placement of windows, warming world should in relation to the path of the sun. not build glass houses” The basic idea is to find ways to minimise the amount of sunshine So why have we fallen into this entering windows in summer glass trap? Partly, it is a matter of but maximise it in winter, such culture. Glass is fashionable, and as through long roof eaves (see most architects don’t understand diagram, above). that buildings need to be designed Besides good insulation to keep differently in a world facing the heat out, buildings should catastrophic global warming. be slow to warm up. That means Although that is starting to having a high thermal mass, such change, Roaf says, much of the as thick walls made of a dense focus has been on energy material, or sinking the building efficiency. So if engineers design a into the ground. It should also cooling system for a building that be possible to get a good air flow requires less energy, it is hailed as through the house at night – for a “green” building. Few are trying instance, by having windows that to create buildings that don’t need can be left wide open without cooling systems in the first place. compromising security. To tackle this, governments All this means we should be building relatively low-rise, cube- must introduce building standards that force designers shaped buildings with thick walls to create truly green buildings. and few windows on the sunny But nothing is being done in the side. That is pretty much the UK, warns the Environmental opposite of what is being done.

Audit Committee. “The government should recognise the importance of protecting public health by introducing building regulations to stop new buildings overheating,” says its report. Can badly designed buildings be fixed? With skyscrapers, there is often little that can be done, but with smaller buildings and houses there is often scope for making them cooler without resorting to air conditioning. The first thing is obviously to insulate them – but the UK has abandoned insulation schemes and rates of its installation have plummeted. The next thing is to stop the 500 watts of heat per square metre you get when sun shines in through a window, says Roland Ennos at the University of Hull, UK. Drawing curtains will help a bit, but it is better to stop the sunshine getting through in the first place. This can be done by installing external shutters, awnings or pergolas, or by planting trees or climbers to shade the exterior. Authorities also need to look at the big picture. The urban heat island effect can warm cities like London by as much as an extra 7°C. But measures like tree planting can drop urban temperatures by several degrees, reducing the need for cooling city-wide and making such places more pleasant. For buildings that do need cooling, there are greener alternatives to air conditioners. For instance, ground-source heat pumps that warm buildings in winter can be reversed in summer to cool them. But these systems are expensive and won’t be affordable for everyone. We need to be doing all these things and more to adapt our homes and cities to a world of ever more extreme weather. Introducing better standards for new buildings is especially urgent, because these buildings could be around for centuries. If they are not fit for purpose, we will all pay the price. Or as Roaf puts it: “The government has to wake up and smell the coffins.” ■ 4 August 2018 | NewScientist | 19

COMMENT

Day of reckoning Earth Overshoot Day is a hugely popular way to highlight our global environmental impact. Here are two views on it… MATHIS WACKERNAGEL

CHARLES PONZI is unfairly blamed for the Ponzi scheme, a scam in which you rob Peter to pay Paul. It’s yet another gender bias in history, because fraudster Sarah Howe predated Ponzi by at least 40 years, swindling Boston ladies. Later, Bernie Madoff took the Ponzi crown – he relied on new investments to provide “returns” to earlier investors, taking from the future to pay for the present. In fact, even Madoff has been outdone: our current economies are running the largest Ponzi scheme ever. We are using Earth’s future resources to power present activities. Currently, humanity consumes the planet’s natural resources more quickly than Earth can replenish them. Debt

“We are running the largest Ponzi scheme ever, using Earth’s future resources to power present activities” balloons will eventually burst. Our ecological debt shows up as carbon in the atmosphere, collapsing fish stocks, shrinking forests, eroding soils and drying up groundwater. Let me be more precise and give you the numbers. That is what ecological footprint accounting was designed for. These accounts are the most pedestrian science you can imagine. For objectivity, they use UN data. They build on the premise that Earth’s ability to renew its resources is the most limiting material factor for the human 20 | NewScientist | 4 August 2018

economy. The accounts add up demands for biologically productive space, given our needs for food, timber, carbon sequestration and room for infrastructure. The sum of this demand is humanity’s “ecological footprint”, now 20.9 billion hectares. But those surfaces of our planet that can provide for this “biocapacity” amount to 12.2 billion hectares. In other words, we are 9 billion hectares short. This means that humanity is currently using nature 1.7 times faster than ecosystems replenish, akin to using 1.7 Earths. This excessive demand can be turned into a date, Earth Overshoot Day. Essentially, it is the date humanity

has used as much as the planet’s ecosystems can handle without going into the red. In 2018, it falls on 1 August, the earliest so far. Currently, carbon emissions are 60 per cent of our footprint. About 150 years ago, that part was negligible. If we want to live up to the Paris Agreement, the carbon footprint should be zero again before 2050. While our planet is finite, human possibilities are not. The transformation to a sustainable, carbon-neutral world will succeed if we apply our greatest strengths: foresight and innovation. This is not only technologically possible, it is also economically beneficial and our best chance for a

prosperous future. If we moved back Earth Overshoot Day by five days every year, we would shift from 1.7 Earths to below 1 before 2050. It is not that hard. Ponzi schemes are bound to come to an end; the question is whether by design or disaster. I prefer design. But it requires honest accounting. And resolve. Most countries say Ponzi schemes are illegal. So what are we waiting for? ■

FRED PEARCE

WELCOME to Earth Overshoot Day – the date when humanity exceeds the resources our planet can provide in a year. For the next five months, we are in eco-debt. Well, kind of. There is no problem with the assertion that we are trashing the planet. We surely are. But I contend that the science behind overshoot day is not a good measure of our use of the planet’s resources. It is a dysfunctional proxy. The analysis sets out to compare our consumption of resources with nature’s ability to renew them, its “bio-capacity”. But the central problem lies in trying to measure our ecological footprint in terms of the size of the planet. The analysis assesses biocapacity at around 12 billion hectares. But it finds that we will use that up by 1 August. In 2018 we will need the biocapacity of 1.7 planets. Rather obviously we don’t actually have 1.7 planets. So, the logic goes, we are drawing down the natural capital of the one we do have.

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Mathis Wackernagel is president of Global Footprint Network, a research organisation based in California. Fred Pearce is a consultant for New Scientist. Calculate your own personal Overshoot Day at footprintcalculator.org

ANALYSIS Brexit stockpiling

FRANK ADAM/GETTY

But individual parts of the analysis are troublesome. We can calculate whether we fell more trees than nature can regrow. It uses UN data, which finds that forest growth outstrips loss. How about cropland and pasture? These are harvested, not consumed. The question is whether we over-harvest, creating deserts or eroding soils. Global Footprint Network (GFN), which does the calculation, admits that no collection of data on annual soil loss exists. So its estimate of cropland and pasture “use” is just a measure of the hectares of such land – essentially identical to the biocapacity. Again, no overshoot. It is not GFN’s fault, but this surely negates what people think the analysis is intended to do. Even so, we have an overshoot overall. How come? The answer lies in the final part of the calculation: climate change. This cannot be measured in hectares, so the metric is a proxy – hectares of forests needed to soak up the carbon dioxide accumulating in the atmosphere. GFN puts this at around 8 billion, or a bit over half Earth’s land surface. These virtual forests don’t exist, which is why the climate is changing. But without them, the analysis would give a 30 per cent undershoot. None of my criticisms deny the importance of climate change. Nor the poor state of ecosystems. In many respects, things are far worse than the overshoot analysis suggests. Soils are being eroded fast; biodiversity is suffering; mismanagement of water is emptying lakes and rivers and polluting oceans. The trouble is none of these can be measured in hectares – and none are in the overshoot analysis. Which, I suggest, is not fit for purpose. ■

The scientific guide to hoarding food Clare Wilson

lentils, are easy to store discreetly. “Lentils and rice is a staple diet for hundreds of millions of people. They take up no space and essentially never go off,” says Lewis Dartnell, author of The Knowledge: How to rebuild our world from scratch. Even with a worst-case Brexit outcome, though, the risk is not so much that the UK may have no food at all, but that the stuff that comes from Europe will be subject to shortages or price increases. About 30 per cent of UK food is imported from European member states and another 10 per cent comes

WATER. Baked beans. Shotguns? Many people occasionally wonder what they should stockpile to prepare for the collapse of civilisation, but don’t get round to doing anything about it. It’s usually the kind of idle speculation that occurs after watching one too many zombie movies. But now the question has become somewhat more pertinent for people in the UK, where the government has announced it is taking steps to make sure the country has enough food if there is a “no deal” Brexit. Prime Minister Theresa May said “For your basic apocalyptic last week that people should be scenario, your main “comforted” by this news. concern is stockpiling Of course, the UK has some enough calories” experience of limited food supplies – rationing began during the second world war and lasted until the from countries the UK has trade deals mid-1950s. But why rely on the with by virtue of being in the EU. This government? If you want to stockpile covers a wide range of food types: for yourself, let science guide the way. fruit, vegetables, eggs, cheeses, For your basic apocalyptic scenario, pork, beef and chicken. Lamb is the your main concern would be exception, coming mainly from British stockpiling enough calories without or New Zealand farmers. taking up too much space. Dried foods, The UK is especially reliant on like wholegrain rice, porridge and Europe for fruit and veg in the winter.

The UK climate does not allow much to grow between December and early March other than potatoes, leeks, root vegetables and brassicas. Obviously most fresh fruit and vegetables cannot be stored for very long. One option for anyone keen to get their five a day would be to stock up on canned produce. But Alex Richardson of the University of Oxford says frozen fruit and vegetables would be better because they have more nutrients. “If you must stockpile, it might be worth investing in a chest freezer,” she says. And speaking of nutrition, you probably shouldn’t forget your omega-3 fatty acids, the best source of which is fish. Here, we shouldn’t turn up our noses at cans, such as tinned mackerel, pilchards and salmon. Tuna that has been tinned in water is OK, but the kind tinned in vegetable oil has little omega-3s left. All this stockpiling – not to mention buying a second freezer – would be less possible for poorer households, of course. The food consequences of a bad Brexit will inevitably be more of a threat for those on lower incomes, who may already be struggling to feed their families. Supermarkets have estimated that if the UK crashes out of Europe without a trade deal, a fallback to World Trade Organization tariffs would bump up the price of European foods by an average of 22 per cent. For some families, that would be no joke. ■ 4 August 2018 | NewScientist | 21

APERTURE

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Star attraction NO WONDER this child is clamouring to touch Bob the tame flamingo. He has become a local superstar on the Caribbean island of Curaçao, after injuring himself by flying into a window of the island’s Hilton Hotel and collapsing unconscious by its swimming pool. Odette Doest, a local vet, treated Bob for concussion, and has since kept him at a wildlife rehabilitation centre she runs as part of her charity, Fundashon Dier en Onderwijs Cariben. Since his crash, Bob’s life has been transformed and he is now an ambassador for the charity. Doest takes him into schools to meet children and reinforce her message about the importance of protecting the island’s wildlife and the fragile habitats on which it depends. The island supports at least three large populations of wild flamingos. The main picture shows Bob’s visit earlier this month to the A. E. Goilo School in Willemstad, Curaçao’s capital city. The photo below shows Bob en route to one of his many celebrity engagements. Andy Coghlan

Photographer Jasper Doest jasperdoest.com

4 August 2018 | NewScientist | 23

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We’ve disrupted the Atlantic’s churn – and that could make future weather even more extreme, finds Michael Marshall

PHOTOMONTAGE: ANDREY POLIVANOV/CHANTAWUTE CHIMWAN/SHUTTERSTOCK

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HE northern hemisphere is roasting. Greece is battling lethal wildfires, and even the UK’s weather has been so hot and dry that record-breaking fires have broken out in its usually damp climes. In Oman on the Arabian peninsula, thermometers registered the hottest night on record anywhere on Earth on 28 June: the temperature never fell below 42.6°C. Climatologists have been quick to point out that extremes are to be expected in a warming world. But there may be more to it than that. The ongoing European heatwave may have been made worse by a consequence of climate change rearing its head after decades of Cassandra-like warnings. For more than a century, the oceans have been changing right under our noses, as a powerful Atlantic current has weakened. The result, it seems increasingly likely, is more extremes of both heat and cold on both sides of the Atlantic – and the prospect of even more dramatic switches to come. The object of concern is the Atlantic ocean conveyor belt, also known as the Atlantic meridional overturning circulation or AMOC. It is part of a global network of currents that push all the water in the oceans up and down the length, breadth and depth of the various interconnected basins. From the tropical Atlantic off the coast of South America, warm surface water flows north towards Greenland and western Europe, bringing with it an uncharacteristically warm climate, carried by the Gulf Stream. The water becomes saltier as it evaporates, and cools as it moves north. Both factors make it denser so that by the time it reaches the Norwegian and Greenland seas, it has sunk by 2 or 3 kilometres. From there, it makes its way back south at depth (see map, page 26). Changes in salinity and temperature in the north Atlantic drive the entire set-up, which has caused concerns that chaos might ensue if anything changes in that region. In 1961 oceanographer Henry Stommel showed that, in theory, these currents could exist in one of two states, with water flowing in opposite directions depending on the balance of temperature and density. At the time, this was just a curiosity. In the 1980s, growing evidence that greenhouse gas

emissions were heating up the planet caused concern that much of the Arctic’s ice would melt, including Greenland’s ice sheet. Climatologists warned that fresh water pouring into the north Atlantic would slow the natural sinking of AMOC waters, and put a brake on one end of the conveyor belt. Then came the finding that the Atlantic conveyor belt had stalled during the last ice age, between 110,000 and 12,000 years ago, when much of northern Eurasia and North America were covered in ice. Battalions of

“Intense heatwaves could be one result of a weaker conveyor belt ” icebergs periodically broke off and went marauding around the Atlantic. Spiked by fresh water, the AMOC weakened. “Because there were similarities between what happened then and what we were predicting in the future, that caused concern that the AMOC could weaken in the future,” says David Thornalley at University College London. The notion was made famous with the 2004 disaster movie The Day After Tomorrow, in which the AMOC shuts down in a matter of days, triggering a snap ice age across Eurasia and North America and ocean-spanning megastorms. In just one of the many exaggerated scenes, characters run away from a wave of extreme cold that instantaneously freezes anything in its path. In reality, a total collapse would probably take decades or a century. The most likely effect would be extreme sea level rise on the US eastern seaboard, extreme heat in Europe and chaotic monsoons in Africa and Asia (see “The consequences of collapse”, page 26). By coincidence, the year after The Day After Tomorrow was released, Harry Bryden of the National Oceanography Centre in Southampton, UK, and his colleagues claimed that the current had recently slowed by 30 per cent. Using data collected on five research cruises that crossed the Atlantic between 1957 and 2004, they found that the amount of heat being transported north had dropped > 4 August 2018 | NewScientist | 25

Atlantic conveyor belt The warm surface waters of the Gulf Stream cool and sink as they move north, then low back south in the deep western boundary current (DWBC) Shallow and hot Deep and cold

BC DW

significantly. A media storm ensued, but Bryden’s evidence was sparse. The main issue was that the current’s strength might vary naturally, from day to day, season to season or decade to decade. Bryden’s study could have mistaken a temporary wobble for a long-term decline. At the same time, climate models suggested that his slowdown was, in fact, down to natural variability. Nevertheless, researchers started keeping a closer eye on trends. In 2004, instruments were deployed to monitor the AMOC. One of these, the RAPID array, relies on an undersea

“The Atlantic slowdown is unprecedented in the past millennium” cable running beneath the current, from Florida to the Bahamas. Because the AMOC carries lots of salt, it contains charged ions, and their movement sets up a voltage in the cable, which can be used to estimate the current’s strength. Later, a second array was installed from Labrador in Canada to Scotland. Thanks to RAPID, we now have 14 years of continuous data. “It basically showed that the AMOC has huge variability,” says Laura Jackson at the UK Met Office. Bryden himself co-authored a study of the first four years of RAPID data, showing that the current is strongest in the northern hemisphere autumn and weakest in spring. In it he acknowledged that seasonal changes “might have accounted

AM TRE LF S U G

for a large part of the inferred slowdown”. This comforting conclusion was reinforced by further data. In the winter of 2009-10, the AMOC weakened by 30 per cent, but recovered the following year. The belief is that strong surface winds blowing against the current might have put the brakes on. In this light, Jackson says, many people concluded that the original finding was “a fluke”.

Things began shifting three years ago. To get around the variability problem, researchers sought data spanning even longer timescales. Stefan Rahmstorf at the Potsdam Institute for Climate Impact Research in Germany and his colleagues looked at how sea surface temperatures varied worldwide from 1901 to 2013. Mostly, they found a warming trend, but in the north Atlantic, a blob-shaped region had cooled, particularly since 1970. Tellingly, climate models suggest that such a cool spot is a sign of a weak AMOC. Just months after Rahmstorf’s study was published in March 2015, Europe was hit by a scorching summer that broke a number of temperature records. The following year, Aurélie Duchez of the National Oceanography Centre in Southampton, UK, showed it was linked to the cold spot in the north Atlantic. In the past, similar heatwaves were more likely if the cold spot was more intense. We now have evidence that this mechanism has operated for millennia. It seems the AMOC moderates Europe’s weather, reducing both winter storms and summer heatwaves. Losing it unleashes both. A related possibility is that the recent spate of extremely cold winters and snowstorms in the eastern US might be linked to the current’s weakening. The idea is that the cold patch in the north Atlantic affects the jet streams over North America, unleashing blizzard after blizzard. Back in Rahmstorf’s team, there was another significant finding. Michael Mann of Penn State University had previously estimated

THE CONSEQUENCES OF COLLAPSE The Gulf Stream is notorious for the warm glow it brings to the UK and the rest of western Europe. But if the Atlantic Ocean conveyor belt (or AMOC) were to collapse, the Gulf Stream would vanish, cooling Europe and possibly beyond.

extremely rapid sea level rise along the US east coast – adding 15 to 21 centimetres at New York City by 2100 according to one estimate. This would bring more severe flooding whenever storms hit. It also isn’t certain that there

Some have painted this as a good thing. After all, as temperatures soar because of climate change, surely a bit of fresh air can’t hurt? One study argued that an AMOC slowdown would avoid the many harms a rapidly warming climate would unleash on Europe. Not so fast. For starters, a

would be cooling. A recent study suggests that a weaker AMOC might reduce the deep ocean’s ability to store heat, boosting atmospheric warming. Any cooling that did occur would be localised. “The heat has to go somewhere,” says David Thornalley at University College London. “The north Atlantic might get colder, but it means everyone else is getting

weaker AMOC would shift water around the Atlantic, leading to 26 | NewScientist | 4 August 2018

a bit warmer.” The effects for the rest of the world are murderous. In Central America, Africa and southern Asia, billions of people depend on monsoon rains. A weakened AMOC would shift them hundreds or thousands of kilometres north or south, leaving many regions parched. “Collapsing the [AMOC] would probably be very bad news for the west African Sahel monsoon,” says Tim Lenton of the University of Exeter, UK, adding that the people living there are already among the most vulnerable to climate change. Back in Europe, cooler

temperatures mean less water evaporating to form clouds, which would also make everything drier and affect farmers. The region would get more severe heatwaves, more winter storms and floods; the US may also suffer more extreme winters. Some of these effects are already being felt (see main copy). Finally, a weaker AMOC would affect marine life, including some we depend on. “Important fisheries like cod and mackerel, will migrate with changing circulation patterns,” says Thornalley, adding that some currents play a key role in spreading larvae.

NETHERLANDS MINISTRY OF DEFENCE/EYEVINE

A total collapse of the Atlantic conveyor belt could raise sea levels (left) and shift monsoon rains, with devastating results (below)

enough to sink properly. More often than not, a quarter of the fresh water was still there as spring broke, suggesting the convection current wasn’t working as it should. Then in April, Rahmstorf returned to the fray, armed with better evidence that the north Atlantic cool blob really was a signature of a weak current. His team also reconstructed how the current had changed from 1870 to 2016, and showed that it had weakened by 15 per cent since the middle of the 20th century and, after a brief recovery in the 1990s, had been declining steadily throughout the 21st century. Finally, Thornalley and his colleagues examined Rahmstorf’s claim that the weakening was bigger than anything in the

PRABHAT KUMAR VERMA/EYEVINE

how surface temperatures had changed since AD 900, using records contained in tree rings, marine sediments, ice cores and corals. In that data, the team found no previous signs of a north Atlantic cool spot. They concluded that the AMOC slowdown since 1970 was “an unprecedented event in the past millennium”. “When that came out it was quite controversial,” says Jackson. Some questioned whether the cold blob might simply have been caused by something else. That looks increasingly unlikely. For one thing, it turns out that the older climate models – the ones that had suggested the AMOC was stable during the 20th century – were probably biased towards producing a stable current. For example, Wei Liu of the Scripps Institution of Oceanography in California showed last year that the models don’t capture how salt moves around the oceans. When this issue was resolved, the simulated AMOC became more prone to collapse. Better models have shown that the current can be pushed into an “off” state by fresh water – coming from a melting Arctic, for instance – and will then stay off for more than 400 years. Earlier this year, three studies offered critical evidence that a slowdown is already under way. The first was led by Marilena Oltmanns at the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany. She and her colleagues focused on the Irminger Sea south of Greenland from 2002 to 2014. They found it to be unusually warm and low in salt for several summers, particularly 2010 – exactly the conditions that would weaken the AMOC. What’s more, the winters that followed were so mild that the water never cooled

past 1000 years. They focused on one part of the current: the deep western boundary current or DWBC, which carries the cold waters back south (see map, page 26). To find out how it had changed over centuries, they used sediment cores that had been drilled out of layers of mud and sand on the bottom of the Labrador Sea. The team measured the sediment grains – bigger grains meant a faster current. “A fast-flowing mountain stream has a rocky boulder bed, whereas a slow meandering river has sediments at the bottom,” says Thornalley. In this way, the sediments offered direct evidence of what was happening in the deep-sea currents. They found that the DWBC began weakening around 1750. By 1870, it was significantly weaker than at any point in the previous 1500 years. It has slowed ever since.

Total collapse Put all the evidence together, and the case that the AMOC is getting weaker starts to look quite strong. “From a whole range of different types of evidence, we get the same answer,” says Thornalley. “If I had to guess, I would say the AMOC is decreasing and it’s not just an internal variability that is occurring,” says Giovanni Sgubin at the University of Bordeaux in France. Jackson and Oltmanns remain cautious. Jackson wants a few more years of RAPID data, among others, before she accepts that a slowdown is under way. So a weak AMOC could already be affecting weather patterns, but what about the more extreme possibility: a collapse, with the more violent climatic impacts that would follow? The core problem with predicting that eventuality, says Rahmstorf, is that even after decades of study, it is unclear how big a “push” is needed for collapse. As the AMOC slows down, it comes closer and closer to a theoretical tipping point that would lead to its collapse, but “we still don’t know how close to that threshold we are”. “Although we think it’s very unlikely that you would get a sudden collapse of the AMOC, obviously the impacts from that would be huge,” says Jackson. She calls it “a low-probability, high-impact event” – like a financial crash. Only with far worse consequences. ■ Michael Marshall is a writer based in Devon, UK 4 August 2018 | NewScientist | 27

COVER STORY

INSIDE DOPE Medical cannabis is sweeping the world, but we’re hazy about how it works – or if it even does, says Graham Lawton

HEY say that to see the future, you should go to California. So when the Golden State legalised medical cannabis in 1996, we should have seen what was coming. Sure enough, where California led, others followed. Today more than half the citizens of the US have legal access to medical cannabis of one form or another, as do those of a further 44 countries. The United Nations recently convened a special meeting to assess the state of knowledge on medical cannabis, the first time it has ever looked at the drug since blanket prohibition almost six decades ago. As a report on the health effects of cannabis published in 2017 by the US National Academies of Science, Engineering, and Medicine concluded, “this is a pivotal time in the world of cannabis policy and research”. The UK is the latest front line. Public controversy has led to a review of strict prohibition, and upped the likelihood that the country will join the list of those allowing the medical use of cannabis in some form. Whether that is a good idea is hard to call, not least because the term “medical cannabis” covers a multitude of possibilities. At one extreme are freewheeling US states like California and Colorado, where it is all but indistinguishable from recreational use. At the other are tightly controlled systems that closely resemble mainstream medicine. Both

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have their pros and cons. Which should a country choose? Cannabis has been used medicinally for centuries, but it was not widely known in the West until the 1840s. By the 1850s, it was sanctioned as a painkiller, sleep aid and anticonvulsant. But growing concerns about the potential for abuse led to a gradual retreat. In 1961, the UN put cannabis on schedule 1 of its Single Convention on Narcotic Drugs, the strictest level of prohibition and a global diktat to criminalise cannabis for all uses. Modern moves to legalise the medical use of cannabis began in San Francisco in the early 1990s, initially driven by AIDS activists who argued that it could alleviate the nausea and wasting associated with the late stages of the disease. The movement quickly blossomed into Proposition 215, a state-wide referendum that legalised use, possession and cultivation of medical cannabis.

2.1

million people legally use medical cannabis in the US SOURCE: US Census Bureau

That small bud has grown into a rambling weed of medical marijuana legalisation across the US and beyond. Currently 31 US states plus the District of Columbia, Puerto Rico and Guam have legalised it, and an estimated 2.1 million Americans use it legally. Other countries where medical cannabis is allowed include Canada, Australia and Germany (see maps, page 30). The UK’s debate has been sparked by the case of 12-year-old Billy Caldwell, whose cannabis oil, bought in Canada to control a rare form of epilepsy, was confiscated on his return to the country. The outcry has prompted a Home Office review of the law, and doctors in the UK will be allowed to prescribe cannabis-derived medicinal products. But what are countries that legalise such medical use buying into? Smoke or ingest cannabis and you are flooding your body with at least 400 compounds, about 100 of which are classed as cannabinoids. This means that they interact with an important signalling network spread throughout the nervous and immune systems. The endocannabinoid system consists of a group of neurotransmitters that latch onto receptors modulating things including pain, appetite, mood and learning, and which are also involved in brain development and maturation. This is how cannabis exerts its wide>

SARA STATHAS / ALAMY STOCK PHOTO

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TA K E T H E H I G H R O A D Since 1996, when California became the first jurisdiction to legalise cannabis for medical use, many parts of the world have followed suit – leading to a booming global trade

End of prohibition The world, and particularly the US, is a patchwork of different approaches to regulating medical cannabis. Only Canada, Uruguay and a handful of US states have gone the whole hog and legalised recreational cannabis too

Worldwide Fully legal Medical cannabis legal Sativex mouthspray only

US Fully legal Medical use Medical cannabis illegal, but limited use of High-CBD/low-THC oil Illegal

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US states and territories have legalised medical cannabis

Alaska Hawaii

Cannabis is also fully legalised in the District of Columbia and for medical use in the territories of Guam and Puerto Rico

25%

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fewer opioid painkiller deaths in US states where medical cannabis is legal SOURCE: JAMA Internal Medicine vol 174 p1668

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Stocks

Production

Main producers (2016, tonnes)

Consumption

220

95

200 81

180 160

Total

140

210

120

tonnes

100 80 60

21

40 9.3

20

1.5 1.4 0.6 0.5

0 2000

2005

2010

2015

UK Ca na Po da rt ug al Ne Isr th ael er la nd s Ch ile Sw itz US er la nd

As prohibition has rolled back, production has ramped up, with the UK and Canada the largest suppliers and the US the largest importer

As more jurisdictions have legalised medicinal cannabis, business has boomed globally

Medical and scientiic research cannabis (tonnes)

On a roll

44

countries worldwide have legalised medical cannabis

ranging effects, although, with so many compounds sloshing about, it is not clear exactly what is going on. Nobody knows which cannabinoids activate which receptor, or how they interact. Especially mysterious are “entourage effects”, meaning certain cannabinoids are only active in the presence of others. That alone is enough to rule out cannabis in its most basic form as an orthodox medicine, at least within existing systems. Regulatory agencies such as the US Food and Drug Administration (FDA) only stamp their approval on single, highly purified active compounds or, at a push, a mixture of two or three. Yet, in many places, patients can ask for a prescription for “whole” cannabis – in other words the flowers, buds and leaves – which they are free to consume, and in some cases grow, as they please. This has sent global production and consumption of cannabis for medical use soaring (see graphics, left), but is largely a result of persistent lobbying rather than careful scientific research. In the US and Canada, much of what passes for medical cannabis is actually a smokescreen to legalise recreational use, says Robin Murray at the Institute of Psychiatry, King’s College London.

Wild West system

Main importers (2016, tonnes)

0.7

Ita ly

Ge rm an y

US

1.6

SOURCE: incb.org

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That is not to say that cannabis or its constituents have no role in medicine. Despite being classified as a schedule 1 drug by the UN and the FDA, meaning it has no accepted medical use, there is convincing evidence that it helps with a number of conditions. That number is three. Or seven, depending on how you count them. The shorter list is as follows: pain, spasticity from multiple sclerosis, and nausea and vomiting caused by chemotherapy. According to the National Academies report, these are the only conditions for which there is “conclusive or substantial” evidence of effectiveness. The longer list also includes appetite loss caused by AIDS and cancer and two rare forms of epilepsy, on the basis that cannabis-based drugs have been approved to treat them. But the list of other conditions for which cannabis has been claimed to be effective is much, much longer and reads like a medical encyclopaedia. There are more than 80 of them, including some of the world’s most burdensome diseases – cancer, depression, Alzheimer’s, hepatitis C and addiction – plus everything else from asthma and chronic kidney failure to autism.

CANNABIS VS OPIOIDS One good reason for considering legalisation of cannabis or cannabis extracts to treat pain is that this may reduce consumption of another class of drugs that cause enormous harm: opioids. In the US, some 100 people a day die from accidental overdoses of these drugs. Most of the deaths are among people who became hooked on prescription opioids given to treat chronic pain. The crisis is now spreading to other countries. There is some evidence that legalising medical cannabis can reduce the consumption of opioids and the resulting death toll. In 2014, a team led by Marcus Bachhuber, then at the Philadelphia Veterans Affairs Medical Center, collated data on opioid  deaths across all 50 US states from 1999 to 2010. They found that states where medical cannabis was legal – just California, Oregon and Washington at the start of the time slice, joined by Alaska, Colorado, Hawaii, Maine, Michigan, Montana, Nevada, New Mexico, Rhode Island, and Vermont at the end – experienced 25 per cent fewer overdose deaths. More recently, other researchers have found that opioid prescriptions fall when states legalise medical cannabis. The drug is much safer than opioids, with no recorded deaths due to overdose. It is also less addictive.

Many of these conditions have found their way onto official lists of conditions that are eligible for a cannabis prescription, despite there being no scientific evidence that cannabis is effective for them. California, for example, includes anorexia, arthritis, cancer, glaucoma and migraine. Several US states have recently included post-traumatic stress disorder. Illinois lists 40 qualifying conditions. Across all US states with legal medical marijuana, a total of 53 are recognised, says Kevin Hill, an addiction psychiatrist at Harvard Medical School. Most US states with medical cannabis also allow doctors to prescribe cannabis for “any other illness for which marijuana provides relief”, which opens the door to it being prescribed for almost anything. For many people with these conditions, access to medical cannabis makes their > 4 August 2018 | NewScientist | 31

Psychotic risks The exact make-up of what is being ingested is often not clear. Different cannabis strains vary widely in their constituents, especially in their ratio of the two most abundant cannabinoids: delta-9-tetrahydrocannabinol (THC), which is powerfully psychoactive, and cannabidiol (CBD), which is not. That’s true even for medical-grade cannabis grown under controlled conditions. The Canadian grower Tilray, for example, sells products with specified amounts of THC and CBD, but they all come with a disclaimer that THC and CBD levels may vary considerably. This is a serious problem, says D’Souza. “Patients will have to experiment with different strains and doses to achieve the desired effects.” The use of whole cannabis also opens people up to some of the well-known risks that recreational users face. One is dependence, which despite cannabis’s reputation as a nonaddictive drug is a real risk. According to Murray, about 1 in 11 people who try cannabis become dependent on it. People also become tolerant to the drug and need to escalate doses to get the same effect. Next on the checklist of concerns is psychosis. Cannabis consumption is a proven 32 | NewScientist | 4 August 2018

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Approximate number of conditions for which cannabis has been claimed to be effective risk factor for short-term psychotic breaks as well as chronic psychoses including schizophrenia. “We can say with absolute certainty that cannabis carries severe risks,” says Adrian James, registrar of the UK Royal College of Psychiatrists. A body of work by many research groups suggests that the average cannabis user is about twice as likely as a non-user to develop a psychotic disorder. These risks seem to be caused by THC, and are exacerbated by heavy consumption, especially early in life. For that reason, says Murray, they are mainly a worry for recreational users, who tend to be young and consume more. The cannabis plant makes both THC and CBD from the same precursor chemical, and the more there is of one, the less there is of the other. The black market is increasingly dominated by high-THC “skunk” cannabis, which many users say gives them a better high. Since the 1970s, the average THC content of street cannabis has more than

doubled, from about 6 to 14 per cent, and it now contains little or no CBD. CBD seems to counteract the addictive and psychotic effects of THC; it may be a useful antipsychotic medicine in its own right and is the active ingredient in the “cannabis oils” recently approved to treat rare forms of epilepsy. Contrary to popular belief, these conditions do not respond to THC. Addiction and psychosis ought to be a minor problem for medical cannabis. Some strains are bred to have high CBD and low THC content, and others are close to 50:50. But even in this market there is evidence of a consumer preference for high THC varieties. For example, Dutch grower Bedrocan’s most commonly used whole cannabis contains 22 per cent THC and almost no CBD. A recent study found that most commercial cannabis products fall into the high-THC bracket. As yet there is little sign of an actual problem. Medical cannabis has been freely available in California for more than two decades, and there is no hint of an epidemic of addiction or mental health problems. Ditto in the Netherlands, which effectively legalised cannabis decades ago. Nor is there much evidence that medical cannabis increases the rate of traffic accidents or is a gateway to other, more harmful drugs – common complaints from opponents of legalisation. The reverse is The case of a boy called Billy Caldwell sparked a debate in the UK about medical cannabis

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quality of life immeasurably better. “I’ve worked with many people who are medical users of cannabis and I’ve seen some truly remarkable effects,” says Peter Reynolds, president of UK campaign group CLEAR Cannabis Law Reform. However, the lack of scientific and regulatory rigour both worries and irks mainstream medics. It is not clear why the approval process for medical cannabis should be any different from that for other drugs, says Deepak D’Souza of Yale School of Medicine: evidence supporting its use should come from large, double-blind, randomised, placebocontrolled clinical trials. Murray agrees. “My view would be that they should just go through the regular medicines approval system.” The Wild West approach is made worse by the variety of cannabis preparations, recommended doses and methods of administration. Besides the buds, leaves and flowers of whole cannabis, there are resins, oils, waxes, tinctures, creams and patches. Cannabis can be smoked, vaped, eaten, drunk, popped under the tongue, applied to the skin and inserted into the anus or vagina. Some is cultivated by commercial farms, but much is home-grown.

BLAINE HARRINGTON III / ALAMY STOCK PHOTO

true, in fact: US states where medical cannabis is legal have significantly lower rates of death from addiction to opioid painkillers (see “Cannabis vs opioids”, page 31). But little is known about the long-term effects of using cannabis, especially on those who start as adolescents and young adults. This issue really worries some researchers. There is growing evidence that the endocannabinoid system has a pivotal role in neural development, guiding the generation, and growth of brain cells and the process of synaptic pruning, a major event in brain maturation occurring mainly in adolescence that weeds out unnecessary connections.

Cheaper and easier The effects of flooding this system with powerful chemicals such as THC are not well-known, but animal studies and studies of teens who use cannabis regularly hint that it can lead to long-lasting emotional, cognitive and behavioural problems, including a drop in IQ. Given that brain development continues into the mid-20s, this suggests that medical cannabis should be prescribed sparingly to people under 25, says D’Souza. Perhaps the answer is to rein cannabis in and allow only treatments that satisfy normal standards of evidence. This is the principle used in less freewheeling jurisdictions, where the prescription of medical cannabis dovetails more-or-less seamlessly with orthodox medicine. Patients are diagnosed in the normal way, then prescribed standardised drugs based on compounds in cannabis or extracted from it. Many countries, for example, allow Sativex – an oral cannabis extract containing roughly equal amounts of THC and CBD – for muscle spasticity and pain associated with muscular dystrophy. This approach would annoy the cannabis lobby, but arguably would be no great loss to medicine. For the conditions for which good evidence exists, medical cannabis does not necessarily mean smoking a joint or drinking cannabis tea. All can be – and often are – successfully treated with synthetic cannabinoid pharmaceuticals or standardised cannabis extracts. Some may not require cannabis at all. A recent review carried out in Germany, where medical cannabis use is soaring after a ruling that health insurers must cover the cost, concluded that conventional drugs were usually more effective. Where cannabis was the right choice, synthetic

cannabinoids were better, cheaper and easier to administer than herbal cannabis. That doesn’t impress some advocates of medical cannabis, who argue that the whole plant is more effective for the very reason it is seen as problematic: it contains a cocktail of interacting ingredients rather than just one purified molecule. “It can’t be regarded in the same simplistic sense as single-molecule medicines, that is why it is so difficult to come up with a way of regulating it,” says Reynolds. And it is true, says Hill, that our current medical exploitation of cannabinoids is poor. Thus far, mainstream pharmacology has only

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Number of conditions with “conclusive or substantial” evidence of cannabis being effective SOURCE: US National Academies of Science, Engineering and Medicine explored THC and, to a lesser extent, CBD. “We’ve got 100-plus cannabinoids,” says Hill. “Maybe the other cannabinoids, or combinations of cannabinoids, can do better than what we’ve got”. “There may be a lot of mileage in cannabis products,” agrees Murray. The fact that the evidence is lacking may simply reflect a dearth of research, which is perhaps no surprise given that the drug is listed on schedule 1 and is

Taking weed “whole” might not be the most effective option for medical treatments

expensive and complicated to study. Performing large and high-quality clinical trials of whole cannabis is possible, but difficult. The lack of standardisation is a problem, and the characteristic taste and odour makes finding a placebo tricky. A review by the World Health Organization found only 12 placebo-controlled trials of whole cannabis; most were small and inconclusive. That said, the existing system does not stop new cannabis-based drugs from coming on to the market. Epidiolex, recently approved in the US to treat two rare forms of childhood epilepsy, is essentially purified CBD extracted from cannabis plants, and similar to the cannabis oil confiscated from Billy Caldwell. All the signs are that the UK will opt for a conservative, but evidence-based approach, perhaps legalising the prescription of cannabis-based pharmaceuticals for a narrow list of conditions, but not medical weed. To many, that would be welcome progress from the rigid prohibition of the past without opening the back door to full legalisation. “I’m not against medical cannabis, there’s merit in it,” says Murray. “But it can also be a foot in the door towards recreational cannabis.” Nine US states, including California and the District of Columbia, plus Canada and Uruguay, have gone all the way and legalised recreational cannabis after experimenting with medical use for a few years. That is a whole different debate – but where California leads, others follow. ■ Graham Lawton is a feature writer for New Scientist 4 August 2018 | NewScientist | 33

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Robot laws What rules should machines follow when they interact with us, asks Douglas Heaven

38 | NewScientist | 4 August 2018

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HE car’s computer saw Elaine Herzberg pushing her bicycle across the highway a full six seconds before it struck her. Travelling at just under 70 kilometres per hour, it had more than enough time to stop or swerve. But it did neither, hitting her head on. Herzberg died in hospital, the first pedestrian to be killed by an autonomous vehicle. A preliminary investigation by the US National Transport Safety Board into the collision, which happened in Tempe, Arizona, in March, found that the emergency brakes of the Uber-operated car were designed to be disabled when driving autonomously to ensure a smoother ride. It was also not designed to alert the human operator of danger. We are a far cry from Isaac Asimov’s First Law of Robotics: a robot may not injure a human or, through inaction, allow a human to come to harm. Of course, Asimov’s laws are fictional. They are also 75 years old. But the idea of rigid rules that keep wayward robots in check has stuck around in the popular imagination. Today, we find ourselves in a world fast filling with robots. They are driving our cars, performing our medical procedures, influencing our elections and threatening to take our jobs. It is obvious we can’t live without them, but the deeper question of how we live with them remains unanswered. The past couple of years has seen a slew of

reports from governments and think tanks offering policy recommendations, but so far Asimov’s model of neat self-contained commandments remains a fantasy. How do we change that? Mady Delvaux, a member of the European Parliament for Luxembourg and author of an EU report on laws for robotics, compares the present situation to when cars first started to appear on roads. “The first drivers had no rules,” she says. “They each did what they thought sensible or prudent. But as technology spreads, society needs rules.” The trouble is, robotic intervention into human affairs is going to require something far more comprehensive than the highway code. Legislation that protects passengers and pedestrians from driverless cars, for example, will be powerless to stop data-scraping algorithms from influencing our vote. Medical robots programmed to diagnose and treat people will need different regulations from those sent onto the battlefield. “AI is not a single thing that can be regulated,” says Steven Croft, the Bishop of Oxford, who sits on the UK House of Lords Select Committee on Artificial Intelligence. “There are different risks, different physical and emotional dangers.”

Code of conduct There is another hurdle, too. Interpreting rules requires common sense. It’s not clear how you would encode even Asimov’s clearcut commandments in a way that a machine could be trusted to follow, says Ulrich Furbach at the University of Koblenz in Germany, who works on automated reasoning. He knows because he has tried. “I gave up, it’s much too difficult,” he says. The trouble is that the laws are too general and don’t allow for context. For Asimov, this was probably part of the point. Many of his stories explore the unintended consequences of robots trying to apply the laws in different scenarios. In Runaround, the 1942 story in which they first appeared in print, a robot gets stuck in a loop when it tries to satisfy the Second Law (obey the orders given to it by human) and Third Law (protect its own existence) at the same time. “Asimov’s laws are perfect for novels but not for putting into practice,” says Delvaux. Ultimately, the debate boils down to questions of ethics rather than technology. What values do we as a society consider to be worth protecting? Croft stresses the need to avoid the “philosophy of extreme libertarianism” of places like Silicon Valley > 4 August 2018 | NewScientist | 39

“AI will need a new ethics – one shaped by society rather than shaping it” One scenario often invoked to show the dangers of letting AI decide for itself is the so-called trolley problem, in which a driverless car must choose who to kill in the event of an accident that is certain to be fatal to either the car’s occupants or pedestrians, depending on its action. But Ryan Calo at the University of Washington in Seattle finds the thought experiment ridiculous. It is an odd assumption to make that a robot has no choice but to kill, says Furbach. “Nobody asked me about the 40 | NewScientist | 4 August 2018

FIVE COMMANDMENTS Any universal laws of robotics will probably include the following

Law #1: A robot may not injure a human or allow a human to come to harm – unless it is being supervised by another human. Law #2: A robot must be able to explain itself. Law #3: AI should resist the urge to pigeon-hole. Law #4: A robot must not impersonate a human. Law #5: A robot should always have an off switch.

trolley problem when I took my driving test.” More interesting are the new possibilities that technology brings about. Here is one scenario suggested by Calo. Imagine an autonomous car with a hybrid motor that can charge its battery by running its petrol engine. One of this car’s goals might be to maximise its fuel efficiency. After a few days on the road it learns that it is most efficient if it starts out each morning with a fully charged battery and decides to run its engine in the garage overnight, killing everyone in the household through carbon monoxide poisoning. This would be a clear violation of any do-noharm-to-humans law but one that was hard to foresee. In such cases, how do we work out what went wrong and who is to blame? “There will be accidents,” says Rebecca Crootof at Yale University. “The question is, will we let the harm fall where it lands, or will we figure out how to hold appropriate entities accountable and ensure that victims are compensated?” Delvaux believes that responsibility for robots lies with the manufacturers. “If you put something on the market you should be liable for it,” she says. Croft agrees: “Responsibility extends to the things you create,” he says. To manage liability, Delvaux suggests that robots should be given an e-personality that would act as a handle for the group of people behind it, in much the same way as companies are treated as individuals under the law to ensure collective responsibility for their actions. “A corporation has humans behind it,” she says. “It’s the same for a robot.” The trouble is that liability law typically

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or the totalitarian approach employed by countries such as China. “The new power that AI brings needs a new kind of ethics,” he says. “It’s going to be vital for the sake of human flourishing that this is shaped by society rather than shaping society. It’s in the interest of individuals not to allow private companies to set the agenda.” As Croft’s remarks highlight, different places have different cultures and different cultures breed different laws. Japan is much more comfortable with the idea of companion robots than many other countries, for example. And as shown by the recent fuss over GDPR, Europe has different attitudes towards privacy and data collection than the US. Nonetheless, there are surely some guidelines that everyone might be willing to sign on to. Not allowing robots to harm humans seems like a no-brainer. A UN ban on autonomous weapons has widespread support, for example. But some argue that letting robots kill might actually save lives, by reducing the number of lethal mistakes made by human soldiers. A similar argument is used to justify the occasional fatal accident with driverless cars and medical robots: we cannot cut the risk of harm to zero, but humans will be far safer with machines than we are with one another. Many find such utilitarian reasoning unpalatable, however. “The taking of life in war can only be justified in the most extreme circumstances,” says Croft. “Human judgement is therefore a very important part of the regrettable waging of war. Anything that moves away from that is ultimately dehumanising.” Wherever robots have the capacity to inflict harm, therefore – in the operating theatre, on the battlefield or on the road – human oversight is essential.

requires defendants to have foreseen the outcomes of their actions. But with artificial intelligence software that learns, this may not be reasonable – as in Calo’s battery-charging scenario. To avoid such unpredictable behaviour from ever arising, one German commission has suggested that there should be no self-learning components in driverless cars, says Furbach, “Which is silly. You want it to be able to improve.” What we can ask for instead is that a robot is able to explain itself. AI is starting to be used to predict our fitness for a job or the likelihood that we will commit a crime, for example – decisions that we should have a right to question. The AI Now Institute, a cross-

Hear roboticist Patricia Vargas discuss whether robots should have rights at New Scientist Live 20-23 September. › More information newscientistlive.com/mag

In Japan, human-like companion robots are already accepted

disciplinary research centre at New York University, recommends that organisations involved in high-stakes domains like welfare, criminal justice, healthcare and education should no longer use black-box systems whose algorithms cannot be scrutinised. Ensuring the responsible use of algorithms may mean we need new hybrid approaches to AI, where machine learning software is combined with techniques that are more easy for humans to understand. This is an exciting new research area, says Furbach. For Anne-Marie Imafidon, a trustee at the

attachments easily. We have barely begun Institute for the Future of Work in Palo Alto, California, if we want AI to provide maximum to consider what types of emotional relationships people might have with humanbenefit with the least harm, the key is not just to make machines understandable to humans, like companion robots, for example. Cultural but to make them better than we ever could be. differences may come into play. “In Japan, robots caring for the elderly is completely Her answer is to make sure machines don’t acceptable,” says Furbach. “In Germany, it’s share our obsession with categorising things. considered inhuman.” That way we might avoid some of the bias But we can probably all agree that however that creeps into our AI and skews automated lifelike a machine appears to be, we should decision-making. always be able to tell whether we are in fact When we train software, we typically ask it interacting with a machine or human. “We to label things – is this a dog or a cat? But once can’t prevent manufacturers from putting you lump something into a category – black human-like robots on the market because male age 18-25, woman over 65 – a lot of consumers will buy them,” says Delvaux. assumptions come into play that may not “But we should make people aware if they be relevant to the task at hand. interact with a robot that it is not a human.” Imafidon cites Netflix as an example of categorisation done well. If you go to the cinema to see a film soon after it is released, “We must be careful it you sometimes get asked what you thought isn’t only employers that of it. Your response is then dumped in with those of your demographic: women of this age benefit from robots” like this film, for example. But Netflix tailors In other settings, even if robots don’t look its recommendations to individuals: people particularly like us, they might still be able to who liked this film also liked that one. Your take our place. “Robots could be a liberating gender and age have nothing to do with it. force by taking away routine work,” says Tom Getting machines to treat people more as Watson, deputy leader of the UK’s Labour individuals is the most important principle Party who set up the Future of Work we should aim for, says Imafidon. Yet such Commission last year to look at how new laws could easily infringe on our privacy, technologies will affect employment. He is, watching our every move and learning our however, concerned about the imbalance in every preference before using that data to power between those calling the robot shots make a profile that gets used against us. and the rest of us. “We’ve got to be careful that AI-assisted profiling is already exacerbating big corporations and employers don’t amass big problems in society, such as Russian all the benefits while ordinary workers are left agents using Facebook’s algorithms to to lump the negatives,” he says. seed the social network with tailor-made In our increasingly automated world, it is propaganda. Perhaps we would see more easy to forget that machines are programmed, of the advantages if we had some guarantee owned and operated by humans. Like any that the data was used in an unbiased way. other invention, their decisions, purpose If we can overcome these challenges, and function are all designed with some machines that save lives, account for their higher, all-too-human goal in mind: safety, actions and treat us all fairly would be comfort, efficiency, profit. Designing laws for welcomed into most societies. But as we machines to follow is an entertaining thought become capable of creating AI and robots experiment, but ultimately a distraction. that are more and more human-like, we The real robot laws need to be written to keep must consider the kind of interactions we people in check, not machines. are comfortable having with the machines. “This is a debate for everyone in the world,” Voice-recognition technology lets us talk says Croft. “As a human race, we need to access to our devices more or less naturally. Google’s deep traditions of wisdom to address these Duplex software lets AI-controlled virtual fundamental questions. We cannot answer assistants book appointments over the phone them through technology alone.” using a synthetic voice that is realistic enough There is at least one technological fix to make a person on the other end of the line we might all agree on, however. “A human think they are talking to another human. should always be able to shut down a And roboticists are crafting humanoid robots machine,” says Delvaux. ■ with lifelike flesh and hair. Uncanny, certainly. But there is a bigger Douglas Heaven is a New Scientist consultant concern here. Humans form emotional 4 August 2018 | NewScientist | 41

PROFILE

Something in the water When Mona Hanna-Attisha discovered the children of Flint were being poisoned, she risked her career to expose it. Colin Barras meets her

Flint residents protested again and again about the state of their drinking water 42 | NewScientist | 4 August 2018

Mona Hanna-Attisha, and the river at the centre of the crisis

By early 2015 the Flint authorities admitted that the water had initially contained potentially harmful contaminants, but stressed that it was now safe to drink. Hanna-Attisha had trusted that line. Born in the UK to Iraqi parents, HannaAttisha has lived in Michigan since she was a child; her father was a GM engineer. It was a chance conversation with a childhood friend that alerted her to the problem. The friend, an environmental engineer, told her about a report by Miguel Del Toral at the Environmental Protection Agency. He and Flint resident LeeAnne Walters had concluded

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T’S the morning of 24 September 2015, and Mona Hanna-Attisha is hours away from the biggest moment of her scientific career. Then her phone rings. As she recalls in her new book, it was a representative from her medical school at Michigan State University, calling to say the institution wasn’t in a position to support her in what she was about to do. “I felt like I was being thrown under a bus,” she says. Hanna-Attisha was about to go public with some controversial and horrifying evidence: that the children in Flint, Michigan, were being poisoned by lead in the drinking water. Her revelation went against the state, the scientific consensus – and now her university. Just a month or so earlier, Hanna-Attisha had been urging the children in her care to drink the water in place of unhealthy sugary drinks – she felt it was her duty as an associate professor at MSU’s College of Medicine in Flint and a paediatrician in the city’s Hurley Medical Center. What had changed? Concerns had been growing about Flint’s water supply for well over a year. When car giant General Motors (GM), founded in Flint, began downsizing its operations there in 1978, the city’s economy went into a long decline. In April 2014, as a money-saving measure, the city stopped buying its water supply from nearby Detroit, opting instead to pull water from the Flint river. It wasn’t long before locals began to complain that the water smelled and tasted bad.

that the Flint River water was not being treated properly and as a result had begun to corrode the city’s aged water pipes. They reported lead in the water supply and speculated that it was coming from those pipes. There is no safe level of lead in drinking water. It affects every organ in the body and especially the nervous system. “Lead is a neurotoxin,” says Hanna-Attisha. “It is potent and its effects are irreversible.” Children are particularly vulnerable because their brains are still developing. “Even the lowest levels can cause steep declines in cognition,” she says. The level of lead in Flint’s water wasn’t low: some samples contained 13.2 milligrams of lead per litre. It wasn’t just unsafe to drink, it should have been handled as hazardous waste. “It was a call to action,” says Hanna-Attisha, and she immediately tried to draw attention to the problem. To her dismay, she says, the authorities showed no desire to act. Even some of her colleagues seemed unconcerned: they agreed that children are at risk from paint – lead was once added as a pigment – but not from water. Papers from as early as the 1980s concluded that lead in water can leach into the body, but

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other studies found no clear link. Although the EPA considers water with a high lead concentration to be hazardous, this historical confusion seems to linger. If she was to change minds, Hanna-Attisha realised she would need evidence that lead levels in the blood of Flint residents had risen after the water switch. The clock was ticking: thousands of people were drinking Flint river water. But getting access to such data can take years. When a similar crisis played out in Washington DC in the early 2000s, Marc Edwards of Virginia Tech in Blacksburg was only able to show that lead poisoning had occurred four years after the crisis ended. But Hanna-Attisha is a doctor and the Hurley Medical Center tests the blood lead levels of Flint’s children as part of routine healthcare. She already had the data. She and her team worked round the clock. “We checked, we double-checked, we triplechecked, we quadruple-checked this data,” she says, and the results were clear. The number of children with high levels of lead in their blood had risen significantly following the change in water supply.

On 21 September, she went to the local authorities with her results, but she says they seemed unwilling to act. Hanna-Attisha felt she had no choice but to go public. As the hour of the press conference approached, the room filled with journalists and camera crews. Flanked by her team, Hanna-Attisha remembers her voice sounding calm and assured – even as her heart thudded in her

“When the entire state is telling you you’re wrong… it is hard not to believe them” chest. She had felt like the holder of an awful secret, and it was a relief to set it free. By early evening she was national news. Instead of being congratulated for her work, however, she found herself under attack. A spokesperson for the Michigan Department of Environmental Quality called her conclusions “unfortunate” in a time of “near hysteria”. The state governor’s office went further, saying Hanna-Attisha’s team had “spliced and diced” the data. “That was definitely the lowest point,” she says. “When the entire state is telling you

you’re wrong, that feels like crap. And it’s hard not to believe them at a certain point.” Days passed. Hanna-Attisha says she was sick with worry. What if she was wrong and worrying people needlessly? Or, worse, she was right and nothing was going to happen? Then, suddenly, the local authority declared a public health emergency. On 1 October it announced that residents should drink bottled water or use water filters. Significantly, some reporters had analysed figures the state had released to counter Hanna-Attisha’s findings and found that they actually supported her claims. Her conclusions were accepted. A fortnight later, Flint was reconnected to Detroit’s water supply – something the state had spent months claiming wasn’t feasible. It was just 52 days since Hanna-Attisha had become aware of the lead problem. The full impact of the crisis remains to be seen. Some research suggests there was a rise in Flint’s miscarriage rate during the period water came from the Flint river. Other studies link the improperly treated water to an outbreak of Legionnaire’s disease in which 12 people died. Some people connected with the Flint water crisis may face charges of involuntary manslaughter. And there are still some concerns around Flint’s water: all of the lead pipes need replacing, and that has not yet happened. Lead exposure causes permanent damage. The only option is to try to mitigate its effects, and that is where Hanna-Attisha is directing her attention. When I visit, she takes me on a tour of the Hurley centre. It’s an ultra-modern, colourful space, and is where she now leads the Pediatric Public Health Initiative, a multipronged project to provide as much health and social support as possible for Flint’s children. Although the parents coming and going from the centre with their children look just like parents everywhere, Hanna-Attisha says that below the surface they are angry – and anxious about what the future holds. Whatever that may be, there is no doubt Hanna-Attisha’s intervention prevented an even worse situation. When Washington DC had its lead problem, the people drank the water for more than three years. “It felt like I was the right person at the right time in the right place and with the right team,” she says. ■ Colin Barras is a science writer based in Ann Arbor, Michigan. Mona Hanna-Attisha’s book What the Eyes Don’t See: A story of crisis, resistance, and hope in an American city is out now (One World) 4 August 2018 | NewScientist | 43

CULTURE

Through a screen, darkly The information age threatens human progress, finds Pat Kane

HILLINGDON Hospital in Greater London is a somewhat crumbly modernist slab of a building. It is fully part of the NHS ragtime: staff shortages, some troubling past safety records for patients and workers, barely sufficient budgets. But stand outside the gates, look to the building’s roof, and you will see giant microwave dishes mounted there. Their function? According to artist James Bridle’s investigations (his knowledge was gleaned through freedom of information requests), they boost the signals of highfrequency financial trading. In that business, nanoseconds matter; the dishes infinitesimally accelerate transmissions between the London Stock Exchange’s data centre in Slough, and the New York Stock Exchange’s servers in Basildon. Staggering amounts of capital, billions and billions, surge across the hospital’s rooftops, slip through relays positioned above a tube depot in Upminster, and go skipping over a Gold’s Gym in Dagenham and high-rises in Barking and Upton Park. Ignore the futuristic blarney, stick to the here and now, and you can locate the kit that sustains our oh-so-chromed virtual future. It is Bridle’s willingness to expend shoe leather in this practice that makes his book much more than the techno-sceptic jeremiad its title would suggest. 44 | NewScientist | 4 August 2018

ISTOCK/GETTY IMAGES

New Dark Age: Technology and the end of the future by James Bridle, Verso

The flow of futuristic-sounding digitised capital shapes our lives

Bridle expresses moral distaste at the excesses and cruelties of digital culture, with its devastating access to our rawest selves, and its historical links to war and imperialism. But he also possesses a nearBuddhist acceptance of how inescapably we are caught up in it. Perhaps this is why he writes so approvingly of initiatives

At one point, he hangs around Farnborough Airport, pointing his camera at the sky to capture twin turboprop aircraft – which he identifies as security-service “sigints”, monitoring the activity of London’s mobile phone networks. Elsewhere, Bridle jumps down a digital rabbit hole to report on the “Stick to the here and now, eerie world of algorithm-generated and you can locate the kit that sustains our oh-sochildren’s TV on YouTube – shows chromed virtual future” with titles like Wrong Heads Disney Wrong Ears Wrong Legs Kids Learn Colors Finger Family like “centaur” chess, in which 2017 Nursery Rhymes. Feedback humans team up with AIs so that loops assemble and reassemble together they can beat the most the heads and body parts advanced programmes. of various cartoon icons. The “darkness” in Bridle’s title Toddlers love it; the BBC series is generated by the unthinkable Teletubbies was derived from density of our information the same child psychology. worlds, and the growing Now human performers are inscrutability of the machine beginning to copy these uncanny intelligences that tend them. We machine-generated montages, can’t afford to be overwhelmed from the US to Thailand, under by all this, he says. Global channels with names like Toy warming’s knowledge explosion, Freaks and Freak Family. for example, compels all good

citizens to be amateur statisticians. But we should understand the scale and intractability of the problem: “Complexity is not a condition to be tamed,” Bridle cautions, “but a lesson to be learned.” The book derives its title from an essay by a founding father of horror fiction, H.P. Lovecraft. “Some day,” wrote Lovecraft, “the piecing together of dissociated knowledge will open up such terrifying vistas of reality, and of our frightful position therein, that we shall either go mad from the revelation or flee from the light into the peace and safety of a new dark age.” In this original and provocative book, Bridle asks us to observe our concrete social surroundings closely, and be ready for strange forces to step out of the current techno-cultural murk. Pray that they aren’t monsters – though what else can they possibly be? ■ Pat Kane is lead curator of FutureFest, and author of The Play Ethic

For more books and arts coverage, visit newscientist.com/culture

DON’T MISS

Ways of the whale

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WHALES might as well be aliens. They live on the same planet as us but we seldom cross paths: hidden in the ocean depths, they remain mysterious. Take their size. Blue whales are the biggest species that has ever lived, exceeding any dinosaurs. The heaviest reliably measured specimen weighed 136.4 tonnes, more than the weight of a Boeing 757 at take-off. Intriguingly, their ancestors were much smaller. Why did they evolve to be giants – and how do they capture enough food to sustain themselves? These are just a few of the big questions that Nick Pyenson, curator of fossil marine mammals at the Smithsonian Institution’s National Museum of Natural Humpback whales behave in ways we are only starting to uncover

History, tries to answer. In his fascinating book, Spying On Whales, we follow his adventures travelling from Antarctica to Alaska to tag whales, hunt their fossils or gain access to their dead bodies, which are hard to come by. Tales of Pyenson’s fieldwork often read like detective stories. Take the events at Cerro Balena, Spanish for “whale hill”. A construction company busy widening the Pan-American Highway in Chile’s Atacama Desert uncovered the site, with dozens of complete skeletons of whales, seals and sloths. Pyenson and his team had to race against the clock to study them: roadworks were due to begin in less than a month. Removing the huge fossils and preserving them would be no easy task, not to mention the fact that by displacing them the team would lose valuable clues about how the whale skeletons ended up there. Was this a mass stranding? Some other catastrophe? Or did they just pile up over time? Spying on Whales delves into the evolutionary history of these mysterious marine mammals,

ESPEN BERGERSEN/NATUREPL.COM

Spying on Whales: The past, present, and future of Earth’s most awesome creatures by Nick Pyenson, Viking

from their beginnings on land to their transition to the sea over a mere 10 million years. At times, however, explanations can get in the way of the drama. But what Pyenson highlights so well is the struggle to address our shocking ignorance. Some parts of whale anatomy, for example, and many body functions are still unknown. Pyenson describes his own accidental discovery of a peculiar sensory organ in rorqual whales when working at a whaling station in Hvalfjordur, Iceland. While advancing our knowledge will mostly depend on disciplines working together, Pyenson’s stint in Iceland also involved a more uncomfortable partnership. Industrial-scale whale hunting has been banned since 1986 in most countries, after nearly 3 million cetaceans were wiped out in the last century for their meat, oil and blubber. But Iceland continued to hunt, albeit with an annual quota. This gave Pyenson a rare chance to access carcasses. He rationalised his situation by telling himself that the whales would be killed anyway and at least he was putting their deaths to good use. Even so, the repercussions of whaling haunt us as we look to the future. Some populations, such as minke whales, have recovered, but others, among them the blue whale, are now endangered. Our inability to clean up our act in terms of climate change and pollution only adds to the challenges facing their survival. Adapting will be key, as “they live at the mercy and curse of human civilization”, writes Pyenson. ■

Read We consume sand more than any other solid resource. So it ‘s no surprise that we are running out of it. Journalist Vince Beiser explores The World in a Grain: The story of sand and how it transformed civilization (Riverhead).

Last chance Difference Engine at the Lisson Gallery in New York takes a surrealist view of our cybernetic age with art that asks: “Do the machines know something we don’t?” Show closes 10 August.

Watch From the company that brought us Netflix hit Stranger Things, The Darkest Minds (pictured) is an outwardly familiar tale of teenagers discovering their superpowers, played at a positively apocalyptic scale. In UK cinemas 10 August.

Play Unexplored: Unlocked Edition, released on 9 August for Nintendo Switch, reinvigorates Dungeons and Dragons-style videogaming. PS4 and Xbox One versions follow soon.

DANIEL MCFADDEN/TWENTIETH CENTURY FOX CORPORATION

Cetaceans are still mysteries to us, finds Sandrine Ceurstemont

The Naked Scientists are here to help us understand. Recent subjects covered by their irreverent science and medicine podcast include addiction and the idiosyncrasies of fighter aircraft.

Sandrine Ceurstemont is a writer based in Morocco 4 August 2018 | NewScientist | 45

CULTURE

Nature in a new light Simon Ings finds illumination in a nocturnal show

AT SOME point in the past couple of years, someone at London’s Natural History Museum must have decided that its exhibitions should be beautiful. The museum’s 2016 show Colour and Vision set a high bar. Its latest, Life in the Dark, shows just how far that process has come. Parts of Life in the Dark are designed by the Jason Bruges Studio, better known for its huge, open-ended, algorithmic artworks, such as the digital crowd massing along a 145-metre-long wall at Sunderland’s train station. And there is its liquid-crystal digital waterfall at the Westfield shopping centre in Stratford, east London, which, years ahead of the competition, proved that bytes, set free with the right algorithms, could be just as unpredictable and fascinating as actual water droplets. The studio’s work at the museum is on a more modest scale, but unobtrusive it is not. One room is hung with card mobiles and a complex lighting track that fills with phantom bats as you walk through it, like a 3D flickerbook. And the final room is lit by bioluminescent denizens of the deep ocean – or at least, their digital avatars. Hung from a false ceiling, Jason Bruges’s complex 3D, 3000-point display accurately reflects the behaviour and movement of more than half a dozen species. Naturally, in the interests of realism, there has been some poetic licence with the light show’s strength and density. Rare sighting: Atlantic footballfish only live in extreme ocean depths 46 | NewScientist | 4 August 2018

It is a moot point whether needle-like middle finger, tapping visitors will appreciate the careful for grubs under the bark of trees research that has gone into all at night, is bad enough, and it those different blues dangling comes as no comfort to read and flashing above their heads, that “If you go into a cave in or whether anyone will notice Central America, you will likely that the animated badger and see huge mounds of guano (bat hedgehog are programmed not poo) covered with feasting to approach each other on the cockroaches”. video wall that greets you when Given enough time, everything you enter the exhibition. The that lives in caves evolves to go journey as a whole is what matters. Life in the Dark’s curators lead “The show is a powerful exercise in letting go of us from English woods at sunset, everything you thought through caves of ever-increasing was normal in nature” depth and strangeness, into the deep ocean where suddenly everything and anything seems blind. Everything shrinks. biologically possible, and not Everything bleaches itself always in a good way. out – except for African dwarf The show is an extraordinarily crocodiles, which turn a sickly powerful (not to say downright orange thanks to the diet of creepy) exercise in letting go their prey. of everything you thought was One inadvertent effect of this normal in nature. The aye-aye’s show was to confirm my lifelong

© THE TRUSTEES OF THE NATURAL HISTORY MUSEUM, LONDON

Life in the Dark, Natural History Museum, London, to 6 January 2019

aversion to caves. On learning that giant centipedes, Scolopendra gigantea, hang from cave walls to pounce on passing bats, I hightailed it to the section about the deep ocean. Here, oddly for an environment that is mostly lightless, virtually no animal is blind. Those that inhabit the middle ranges of the water column use bioluminescence for camouflage, matching their self-made light to the dwindling intensity of sunlight that reaches these depths. Take the spook fish, Opisthoproctus sp, with eyes that point upwards to detect prey, while mirror-like structures in its belly reflect the bioluminescence produced in its gut, breaking up its silhouette from below. Lower still, brittle stars, Ophiomusium lymani, flash brightly to temporarily blind predators, while others produce a gently glowing mucus to signal their toxicity. The Atolla jellyfish, confronting a predator, uses a swirling “burglar alarm” display to attract even bigger predators, triggering the deep-sea equivalent of a bar-room brawl, through which the jellyfish makes an unobtrusive exit. New nocturnal species are turning up all the time, only 5 per cent of the sea floor of the world’s oceans has been explored, and there are bound to be cave ecosystems still awaiting discovery. It is appropriate, then, as well as interesting, that the show contains information about the contributing researchers. Who knows, the videos in this show may inspire a new generation of researchers. They will have to be a lot less squeamish than I am, though. ■

The Department of Psychology anticipates making a tenure-track appointment at the assistant professor level to begin July 1, 2019.

Department of Chemistry Faculty Position in Chemistry The Department of Chemistry at the University of California, Berkeley invites applications for a tenured faculty position at the associate/full professor level with an expected start date of January 1, 2019 LQWKHEURDGO\GH¿QHG¿HOGRIFKHPLFDOELRORJ\$ 3K'RUHTXLYDOHQWGHJUHHLQFKHPLVWU\RUDUHODWHG ¿HOGLVUHTXLUHGDWWKHWLPHRIDSSOLFDWLRQDVZHOO DVGHPRQVWUDWHGOHDGHUVKLSLQFKHPLFDOELRORJ\ WKURXJKSXEOLVKHGSDSHUVSHHUUHYLHZHGJUDQW support, invited lectures at national and international PHHWLQJVDQGXQLYHUVLWLHVDQGUHFRJQLWLRQWKURXJK DZDUGV $OODSSOLFDQWVVKRXOGVXEPLWDFRYHUOHWWHUDQ updated curriculum vitae, and a succinct summary of IXWXUHUHVHDUFKSODQVDQGSDVWWHDFKLQJH[SHULHQFH $GGLWLRQDOO\SOHDVHSURYLGHFRQWDFWLQIRUPDWLRQ IRUWKUHHWR¿YHUHIHUHQFHV:HZLOORQO\FRQWDFW \RXUUHIHUHHVLI\RXDUHD¿QDOLVWIRUWKHSRVLWLRQ DQGZHZLOOVHHN\RXUSHUPLVVLRQEHIRUHGRLQJVR $SSOLFDWLRQVVKRXOGEHVXEPLWWHGHOHFWURQLFDOO\ WKURXJKRXUZHEEDVHGV\VWHPDW https://aprecruit.berkeley.edu/apply/JPF01609 $OOUHFRPPHQGDWLRQOHWWHUVZLOOEHWUHDWHGDV FRQ¿GHQWLDOSHU8QLYHUVLW\RI&DOLIRUQLDSROLF\DQG &DOLIRUQLDVWDWHODZ3OHDVHUHIHUSRWHQWLDOUHIHUHHV LQFOXGLQJZKHQOHWWHUVDUHSURYLGHGYLDDWKLUGSDUW\ LHGRVVLHUVHUYLFHRUFDUHHUFHQWHU WRWKH8& VWDWHPHQWRQFRQ¿GHQWLDOLW\http://apo.berkeley. edu/evalltr.html SULRUWRVXEPLWWLQJWKHLUOHWWHUV The deadline for receipt of application material is -XO\3OHDVHGLUHFWTXHVWLRQVWR/DXUHQ Nakashima ([email protected]  7KH8QLYHUVLW\RI&DOLIRUQLDLVDQ(TXDO2SSRUWXQLW\$I¿UPDWLYH $FWLRQ(PSOR\HU$OOTXDOL¿HGDSSOLFDQWVZLOOUHFHLYHFRQVLGHUDWLRQIRU HPSOR\PHQWZLWKRXWUHJDUGWRUDFHFRORUUHOLJLRQVH[VH[XDORULHQWDWLRQ JHQGHULGHQWLW\QDWLRQDORULJLQGLVDELOLW\DJHRUSURWHFWHGYHWHUDQ VWDWXV)RUWKHFRPSOHWH8QLYHUVLW\RI&DOLIRUQLDQRQGLVFULPLQDWLRQ DQGDI¿UPDWLYHDFWLRQSROLF\VHHKWWSSROLF\XFRSHGXGRF 1RQGLVFULP$I¿UP$FW 8&%HUNHOH\LVFRPPLWWHGWRGLYHUVLW\LQDOODVSHFWVRIRXUPLVVLRQDQGWR DGGUHVVLQJWKHIDPLO\QHHGVRIIDFXOW\LQFOXGLQJGXDOFDUHHUFRXSOHVDQG VLQJOHSDUHQWV7KH'HSDUWPHQWRI&KHPLVWU\LVLQWHUHVWHGLQFDQGLGDWHV ZKRZLOOFRQWULEXWHWRGLYHUVLW\DQGHTXDORSSRUWXQLW\LQKLJKHUHGXFDWLRQ WKURXJKWKHLUWHDFKLQJUHVHDUFKDQGVHUYLFH

We seek candidates with expertise in developmental cognitive science, broadly conceived. Our interest is less in specific topic areas or methods than in innovation and excellence in the applicant’s research program. For instance, in addition to experimental behavioral research on human children, successful candidates might employ cognitive neuroscience, animal cognition, cross-cultural ethnographic work or computational modeling, among approaches. Topics of study might include perception, action planning, conceptual representation, social cognition, reasoning, decision-making or language, among other topics. We seek candidates whose research complements research already going on in the Department, taking it in clearly new directions. The appointment is expected to begin on July 1, 2019. Candidates at all levels are encouraged to apply. Candidates must have a strong doctoral record and have completed their Ph.D. Candidates should have demonstrated a promise of excellence in both research and teaching. Teaching duties will include offerings at both undergraduate and graduate levels. Please submit a cover letter, curriculum vitae, research and teaching statements, up to three representative reprints, and names and contact information of three to five references (three letters of recommendation are required, and the application is complete only when all three letters have been submitted) to http://academicpositions.harvard.edu/postings/8336. Questions regarding this position can be addressed to [email protected]. The committee will consider completed applications starting immediately and on a rolling basis until September 15. Interviews will be conducted in October and November.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, disability status, protected veteran status, gender identity, sexual orientation, pregnancy and pregnancy-related conditions or any other characteristic protected by law.

The Department of Psychology anticipates making a tenure-track appointment at the assistant professor level to begin July 1, 2019. We seek candidates with core expertise in clinical psychology/clinical science whose research programs also bridge to other domains in psychology, neuroscience, or related disciplines. Our interest is less in specific areas than it is in innovation and excellence. The appointment is expected to begin on July 1, 2019. Candidates at all levels are encouraged to apply. Candidates must have a strong doctoral record and have completed their Ph.D. Candidates should have demonstrated a promise of excellence in both research and teaching. Teaching duties will include offerings at both undergraduate and graduate levels. Please submit a cover letter, curriculum vitae, research and teaching statements, up to three representative reprints, and names and contact information of three to five references. In addition, please arrange for three letters of recommendation to be submitted to http://academicpositions.harvard.edu/ postings/8335. The application will be complete only when all three letters have been submitted. Questions regarding this position can be addressed to Jill Hooley at [email protected]. The committee will consider completed applications starting immediately on a rolling basis through October 1. We expect to begin conducting Interviews in October and November.

We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, national origin, disability status, protected veteran status, gender identity, sexual orientation, pregnancy and pregnancy-related conditions or any other characteristic protected by law.

Fellowships for Postdoctoral Scholars "1_oѲ-uv_brv-u;-ˆ-bѲ-0Ѳ;|om;‰ouu;1;m|7o1|ou-Ѳ]u-7†-|;vbm7bˆ;uv;-u;-vo=u;v;-u1_ĸrrѲb1-ࢼomv‰bѲѲ0; accepted from doctoral recipients with research interests associated with the following: Departments - Applicants who wish to conduct research on topics of general interest to one or more of the departments are encouraged to apply. Interdepartmental research is also encouraged. The Departments are: ƒApplied Ocean Physics & Engineering ƒBiology ƒGeology & Geophysics ƒMarine Chemistry & Geochemistry ƒPhysical Oceanography

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6HHLW2QOLQHJobs.newscientist.com/job/1401650052 50 | NewScientist | 4 August 2018

newscientistjobs.com

School of Medicine-Open Rank-Radiation Oncology The Department of Radiation Oncology at the University of Alabama at Birmingham is seeking one or two Ph.D. level scientists with expertise in immune-oncology or DNA repair at the level of Assistant/Associate Professor. This is a tenure earning position. Our goal is the delivery of technically advanced radiotherapy in combination with anew agents developed in the laboratory to enhance cancer care and provide treatment in a pleasing and educational environment. Current recruiting activities are focused on individuals with interest in translational and clinical research. They will have the opportunity to interface with a collaborative group of clinical faculty and laboratory scientists. The University of Alabama at Birmingham (UAB) is a comprehensive urban university with DVWURQJPHGLFDOFHQWHU7RGD\8$%·VFDPSXVFRPSULVHVFLW\EORFNVDQGWKHXQLYHUVLW\LVNQRZQ worldwide for its outstanding research and patient care as well as its innovative educational programs. To learn more about UAB and Birmingham, Alabama, please visit www.uab.edu or www.uab.edu/radonc. You will join 23 other faculty members in the Department of Radiation Oncology. The Department is part of the UAB Comprehensive Cancer Center, a NCI designated Comprehensive Cancer Center. Salary to be commensurate with experience and ability. Please contact Dr. James A. Bonner at [email protected] for more information.

Interested applicants are encouraged to apply online: uab.peopleadmin.com/postings/1826

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LETTERS EDITOR’S PICK

Much of the world is in for a rough ride

From Chris Milligan, Golden Beach, Queensland, Australia Michael Le Page discusses record temperatures across the northern hemisphere (14 July, p 25). Here in Australia, climate modelling by the federal agency CSIRO and elsewhere has led to some sobering predictions for Australian cities in 2100.

52 | NewScientist | 4 August 2018

Prolonged conditions above 35°C and 85 per cent humidity are considered to be beyond human tolerance or habitability. Northern cities like Darwin and Cairns now have several days each year that exceed these limits. It is predicted that in 2100 Darwin will be uninhabitable for a large part of the year without fulltime artificial modification to living conditions. Rural production in almost all mainland Australia will be affected, particularly in northern areas, by this habitability limitation for livestock and humans, as well as the threat of increased bush fires, greater cyclone severity and drought. Regions with similar climatic zones, such as the Middle East, parts of Africa and South Asia, are likely to have a similar experience. The world is in for a rough ride.

Back in the world as it is, protect medical data From Sam Edge, Ringwood, Hampshire, UK Luke Allen calls for “a single, integrated electronic record” for patient data (14 July, p 24). Given ethical, competent and efficient politicians, civil servants, medical professionals and IT contractors this would be a great idea. But we have none of these. We would get an expensive, insecure, inaccurate and buggy system, with records sold or given to companies as in the DeepMind affair (15 July 2017, p 24). No thanks.

The chat-doctor is in the doctor’s waiting room From Neil Doherty, Barnsley, South Yorkshire, UK Clare Wilson reports doctors saying that you cannot replace

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their wealth of experience and “gut feeling” during consultations (7 July, p 25). But when discussion or examination of a patient isn’t enough, doctors rightly send them for tests. We all dislike incursions into our expertise, but sometimes it can be more expert still with more back-up systems. A computer consultation while the patient waits to be seen could give their doctor a head start and cut the appointment time.

How much are farmers to blame for wildlife woes? From Hugh Boyd, Glasgow, UK Chris Packham points out the role of agriculture in wildlife depletion (14 July, p 24). Farming has been blamed for years. Surely readers and viewers would be better stimulated into action by talking about the adverse effect of their

“So the space goat eating ice cream and telling me it needs a new lawnmower is OK… Phew” Rob Z Tobor is somewhat reassured that we have started to uncover the true purpose of dreams (21 July, p 4)

gardening methods and pets. Garden centres have metres of shelves stocked with herbicides, pesticides and fungicides to give gardeners their “perfect” monoculture lawn and tidy beds. Domestic cats kill vast numbers of birds, and dogs, given the freedom of the countryside, wreak havoc on ground-nesting birds. If people got their own plots in order, the birds and insects might come back to reward them. From Michael Hampden-Smith, Zennor, Cornwall, UK Packham confuses cause and effect when he says intensive farming is to blame for the loss of wildlife. The cause is in the low prices paid by supermarkets to food producers, which lead to intensive agriculture. The United Nations Agricultural Outlook report published on 3 July predicts that prices will fall by

10 to 20 per cent for most food commodities, despite this not covering the cost of production in the UK, for instance. In order to survive, food producers will have to intensify even further. If Packham really wants to make a difference, he should lobby government and supermarkets to make sure producers are paid more for their produce.

Pasture land could be nature’s carbon sink From A. K. Vijayakumar, Chandigarh, India Chester Peterson makes the point that not all the pasture land that livestock graze on can produce crops (Letters, 2 June). Instead of using it for grazing, why not allow this land to be reclaimed by forest, or even afforest it, and let nature’s carbon sink do its job?

Why must we listen to public views on GM? From Glenn Pure, Canberra, Australia You accompanied an article on the public acceptance of genetically modified food with a comment piece by Lesley Paterson in favour of scientists asking for public views on where to take GM food (7 July, p 23). This is superficially appealing, but problematic. Such consultations don’t happen for most areas of science – so why for this? Should we ditch research on particle physics if we find that most people don’t care or would rather see the money spent elsewhere? Governments do intervene in capitalist markets, arguing that this is to correct market failures, for example “externalities” such as environmental costs not priced into the market. Unless GM food

has a negative externality, we should allow business to produce food and consumers to chose. In this case, I see governments’ main role being to ensure honesty in marketing, though that shouldn’t mean mandatory GM labelling. Governments also intervene where there are ethical concerns. But do we really want to elevate these when most of the genetic manipulation with techniques such as CRISPR looks remarkably similar to the genetic effect of traditional breeding, but less random, and evidence of it causing harm is lacking? From Kevin Privett, Llandough, Glamorgan, UK I was interested to read about how the GM debate may turn into the gene-editing debate (7 July, p 22). Has anyone done any research asking people who are against gene-edited foods whether or >

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LETTERS not they are also against using gene editing in treatments for, say, cancer?

Human evolution could lead to longer lifespans From James Stone, Sheffield, UK I am surprised Tom Kirkwood is so circumspect about the limits of human longevity (7 July, p 24). Most ideas about ageing explain how we age – mechanisms such as the shrinkage of telomeres at the ends of our chromosomes – not why we age, for example offering evolutionary reasons for an observed lifespan. A notable exception is an idea proposed by Kirkwood himself, involving “disposable soma”. This predicts that lifespan is negatively correlated with death rate; highly predated species should have short lifespans. In support of this is the difference in lifespan between mice, which are heavily predated and live for up to three years, and pipistrelle bats, which are not and can live up to 12 years. This suggests that, in the absence of predation and other TOM GAULD

non-ageing causes of death, humans would have evolved to have lifespans much longer than the current record of 122 years. Tom Kirkwood writes: Q I was asked to comment on a report that was concerned chiefly with mortality plateaus. I touched briefly on the debate over a limit to human lifespan given our current biology. But you address a third point: whether there might be a physical limit preventing humans evolving longer lifespans in the future. I agree that it is conceivable that future evolution could increase human longevity, as it has done in the past. But this would take many generations.

subtly primed by hard-liners to accept “no-deal” as a valid option. Now that the UK prime minister has four politicians who originally supported remaining in the EU in the highest offices of state, those who want total separation will be concocting strategies for the time until the UK is due to leave. If I were one of their number, I would see delay, sabotage and undermining of the hopelessly weak official programme as my priority. Those of us who believe that the entire business is a load of monstrous nonsense need to sustain our vigilance to prevent hard-liners getting what they wanted by default.

I hope for a vaccine Vigilance needed against against Alzheimer’s crashing out by default From Bryn Glover, Kirkby Malzeard, North Yorkshire, UK I was pleased by the unequivocal line you are taking concerning the possibility of a “no-deal” Brexit (Leader, 14 July). The phrase “crash out” would be most appropriate. I hope you sustain this approach, as I fear that already we are being

From Linda Shields, Bathurst, New South Wales, Australia. Sam Wong reports a link between herpes infection and Alzheimer’s disease (30 June, p 12). This made me wonder whether a vaccine could help prevent Alzheimer’s. Immunisation against varicella zoster virus protects children and some others against chicken pox,

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and people over 60 against shingles. This virus is a member of the herpes family. Will it be too much of a stretch to develop vaccines against herpes viruses 6 and 7, which were found in the brains of people who had Alzheimer’s? Perhaps longitudinal studies of those who have been immunised against chicken pox and shingles will reveal a decline in the prevalence of Alzheimer’s. The editor writes: Q It is worth investigating. But we don’t yet know whether herpes causes Alzheimer’s, or in how many cases it may have an effect.

Small is more beautiful than big energy schemes From Paul Whiteley, Bittaford, Devon, UK Tidal lagoons aren’t an easy solution to our energy problems, as Hans van Haren correctly argues (23 June, p 24). Private industry has been trying to get the UK government and taxpayers to underwrite large-scale energy projects like these for years. We should instead spend the money putting solar hot water panels on people’s roofs. Everyone uses hot water and it can be stored easily. If the £20 billion subsidy for the Hinkley Point C nuclear reactor was used to install such systems, they could be fitted in 4 million homes. The payback time is as short as eight years.

For the record Q In 2015, Norway’s sovereign wealth fund was worth around $900 billion (21 July, p 27).

Letters should be sent to: Letters to the Editor, New Scientist, 25 Bedford Street, London, WC2E 9ES Email: [email protected] Include your full postal address and telephone number, and a reference (issue, page number, title) to articles. We reserve the right to edit letters. New Scientist Ltd reserves the right to use any submissions sent to the letters column of New Scientist magazine, in any other format.

54 | NewScientist | 4 August 2018

OLD SCIENTIST What was New Scientist talking about in Augusts past?

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IT’S twice as nice with ice. Most people are usually referring to their gin and tonic, but in August 1961 we were more concerned with fish. Evidence was emerging that the UK’s fishmongers weren’t heeding the adage, and fish were warming up too rapidly in their displays. We reported on 3 August that the spoilage rate of cod increases with temperature at a constant rate between its freezing point and 25°C and pointed out that flavour becomes more unpalatable with every degree of warming. We recommended refrigerated slabs in addition to the usual ice piled around the display. And who knew that the freezing point of a cod was -1°C? We learned more about low temperatures in our 27 August 1981 edition. “Frozen nerves lead to speedy recovery,” we announced. Instead of administering drugs for pain relief after surgery, surgeons at Colindale hospital in London had discovered that freezing nerves around the surgery site – a process they called cryoanalgesia – removed nearly all the pain people experience postsurgery. It was especially effective in chest surgery where ribs have to be parted to allow the surgeon access to the lungs or heart. Patients who were frequently in agony following surgery could move, sit up and – critically – cough to removed phlegm from recovering lungs. Unfortunately, Siberian mammoths didn’t receive the same benefits from freezing temperatures. On 13 August 1994, we reported that mammoths living on the Siberian steppes had died of malnutrition, thanks to the cold and a lack of vegetation. Ironically, the cold had preserved their bodies, allowing researchers to date them as being between 10,000 and 12,000 years old. Gilles Pacaud of the French National Museum of Natural History told New Scientist that the animals “were using up more calories feeding themselves than they were ingesting from the vegetation”. Mick O’Hare

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For more feedback, visit newscientist.com/feedback

FEEDBACK

the cloth-reel Panorama is snippy compared to today’s Hollywood epics, but at least the heavyweight format of this buccaneering tale offers excellent protection against piracy.

Druid Stuart Jeffrey is campaigning for change, pointing out that although only 0.2 per cent of Britons identify as pagans according to 2011 census data, the slot features speakers from religions such as Buddhism and Judaism, which represent 0.4 and

THE UK is wilting in an unseasonable summer, and many organisations are keen to help citizens through the shimmering haze to autumn. Lightfoot describes itself as “a fresh, vibrant and highly innovative cleantech engineering company”, and has tackled an important question for motorists: “Does aircon use petrol?”

FIREFIGHTERS were called to a tortilla chip factory in Austin, Texas, after the snacks spontaneously combusted time and time again. Several pallets of food waste – presumably from the extra spicy variety – set fire to themselves at the unnamed factory, following a new disposal method that “didn’t work out so well”, according to a Facebook post from the Austin Fire Department. “Tortilla chips are big business around these parts,” it said. “So imagine how distressed we were to be called to a fire at a tortilla chip factory earlier this week...not once, but twice!”

PAUL MCDEVITT

If ever there was a time to heap generous portions of cool salsa onto hot chips it was this, but the firefighters opted to quench the flames with traditional water hoses instead.

WHAT do you call a very long, hugely popular story about an ocean voyage that culminates in a spectacle of death in icy water?

Not James Cameron’s Titanic, but the premier cinematic experience of 1848 – now returning to theatres in the US. The Grand Panorama of a Whaling Voyage ’Round the World is North America’s longest painting, so long that it is kept on five spools rather than in a frame. All great sagas need good source material, and the Panorama has 388 metres of it, in the form of painted cotton cloth. The sidescrolling adventure details the four-year voyage of whaling vessel Kutusoff, which set off from Massachusetts in 1841. A travelling show, the mural was drawn between two spools as the co-creator (and former Kutusoff crew member) Benjamin Russell narrated the events to an audience. Following restoration work, the epic has now gone on display at the New Bedford Whaling Museum in Massachusetts. With a running time of 2 hours,

“Major champions are growing younger,” announces The Daily Telegraph. “I knew that golf was good for us,” says Bruce Denness, “but I didn’t know it was that good” 56 | NewScientist | 4 August 2018

Paul Trewavas, who spotted the post, notes that part of the answer reads: “Though it seems hard to believe in our current heatwave, the British climate rarely offers more than 48 hours of consecutive sunshine, so it’s unlikely you’ll always have the aircon on”. “Given that the whole of the UK lies south of the Arctic circle,” says Paul, “I don’t find it at all hard to believe that we never get 48 hours of consecutive sunshine.”

A ZOO in Egypt has been accused of painting black stripes on two donkeys in an attempt to pass them off as zebra. Student Mahmoud Sarhan snapped a photo of one of the cryptids during a visit to the International Garden municipal park in Cairo. With long ears and what looks like crudely-daubed stripes (complete with paint smudges around the head), the effect was more basic than Batesian mimicry. The director of the zoo, Mohamed Sultan, denied trying to make an ass of his customers, insisting to local radio Nogoum FM that the zebra were legitimate. With such airbrushing on offer, are we setting unrealistic beauty standards for natural zebra?

0.5 per cent of Britons respectively. A compelling argument, although Feedback is moved to add that in the same census, 0.7 per cent of Britons identified themselves as Jedis. Could they compel the BBC to include Master Yoda’s homilies on current events? As he might have said: do or do not – there is no try.

A DISCOVERY of some gravity: “it looks like the Chinese have almost cracked anti-gravity,” says Margaret Selby. The shipping label on her new lawnmower cites a gross weight of 7.6 kilograms and a net weight of 9.2 kg. “By putting my lawnmower into a large cardboard carton, they have reduced its weight by 17 per cent,” she says.

Packaging that reduces the weight of the contents would certainly be a boon to delivery companies such as Amazon. Of course, it might also encourage sending small items in ridiculously oversized packages. Perhaps Amazon has its hands on this technology too.

PAGANS have demanded greater representation from the BBC, protesting that their views should be included in the broadcaster’s faith-based Thought For The Day slot on Radio 4.

You can send stories to Feedback by email at [email protected]. Please include your home address. This week’s and past Feedbacks can be seen on our website.

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THE LAST WORD Mixed leaf salad This tree (see photo) has both variegated and normal leaves, with leaves of both types on the same branch. Can anyone explain this distribution of different leaves on the same plant?

Q The form of variegation in this maple tree is called a periclinal chimera. Leaves consist of several layers of cells, each of which develops separately, without mixing cells between layers. In variegated leaves of this type, there is a green inner layer covered by a white outer layer, much like a green hand in a white glove. This entire tree is a combination of cell layers containing either the genes for normal green leaves or genes with a mutation that can’t make the green pigment chlorophyll. When leaves are very young, they consist of only a few cells in a growth tip (the meristem). The cell that will become the outer layer of the leaf comes from the outer layer of the twig, and if it contains the mutation, the layer will be white. But in this early stage of development, cells can accidentally end up in a different layer. That way you can get solid green leaves or completely white leaves. Maple leaves have three cell layers, so even more variation is possible – if the outer layer is white it will give the leaf a narrow white edge; but if both outer layers are white the leaf will have a wide white edge. If you want to propagate such

Q There are two other possibilities for the outcome seen in the photo. The tree may have been infected by a virus that is causing the variegation and this virus may be affecting only parts of the tree. Or the variegated branches could be the result of grafting. Grafting is a technique commonly used by gardeners to reproduce ornamental varieties of plants

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a tree, you have to make sure youtake a cutting from a twig that has variegated leaves. If you take it from a green-leaved one, the resulting tree will have only green leaves. Seeds are formed from just one of the layers, so seedlings from these variegated trees are usually solid green. Any solid white ones won’t survive. Margareth Hop Nursery stock breeder The Netherlands

that cannot be grown from seed. In such a situation, the graft is attached to root stock from a closely related plant. Without pruning, the root stock can also produce branches that appear different to the graft – in this

“The tree may have been partly infected by a virus that is causing the variegation” instance the variegated branches could be from a graft and the ordinary green branches could be from the root stock. Adrian Clayton Biology and Environmental Studies The Sixth Form College Farnborough, Hampshire, UK Q Plants with variegated leaves are often special varieties bought from garden centres or plant

nurseries – they have less lightenergy absorbing chlorophyll than their all-green relatives and so do not compete well in the wild. A variegated form generally first occurs as a “sport”, a random genetic mutation. This could be the result of a stray cosmic ray hitting the DNA of a particular cell in a particular bud, which gives rise to a leaf – and eventually a whole branch – that is variegated. If this is a desired trait, new individuals can be propagated by taking cuttings from the sport, and then cuttings can be taken from those and so on. The result is thousands of cloned individuals all having the same mutated genetic code. This is known as a cultivar. It is common for these variegated clones to suffer a similar fate – a random genetic mutation that leads to a reversion to an all-green leaf. Hence you often find an all-green sport on an otherwise variegated plant. It is worth noting that the allgreen sport will grow faster than the rest of the plant because it has more chlorophyll. Nicholas Hall St Just, Cornwall, UK

This week’s question NECKING IT

Do giraffes get struck by lightning more often than shorter animals like zebras? Nick Ewans London, UK