27 January 2018 
New Scientist

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SPECI A L R EPORT

MAKING MONKEYS

First cloned primates promise a medical revolution

WEEKLY 27 January 2018

OUT OF ARABIA Searching for human origins in war-torn Yemen

SHOULD YOU GO VEGAN?

What it will mean for your life, health and the planet

No3162 £4.10 US/CAN$6.99

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PLUS STRATOSPHERIC SPY BALLOONS / WORKPLACE STRESS / COLLAPSING GLACIERS / BLACK HOLE BLASTS / NO CLIMATE REPRIEVE / ANCIENT DICE / AFRICA’S ANTEATER

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CONTENTS

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Volume 237 No 3162

News Spy balloons watch from above 8

On the cover

Leaders

Special report: Making monkeys First cloned primates promise a medical revolution

40 Out of Arabia Searching for human origins in war-torn Yemen 26 Should you go vegan? What it will mean for your life, health and the planet Plus Stratospheric spy balloons (8). Workplace stress (10). Collapsing glaciers (6). Black hole blasts (7). No climate reprieve (23). Ancient dice (14). Africa’s anteater (24)

3

Monkey cloning won’t change the ethical question. Vegans need facts, not bandwagons

News 4

THIS WEEK Cloned monkeys unveiled in China

6

NEWS & TECHNOLOGY Glacier collapse triggers avalanches. How insect wings evolved. Black holes fire triple-dose of speedy particles. AI cracks ancient cipher. Spy balloons. Thankless boss to blame for work stress. Bitcoin’s failed utopia. Deadly stellar flares may also seed life. People who name smells as easily as colours. How dice became fair. Testosterone makes you a metal head

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17 IN BRIEF Exoplanet mirages. Tiny wild cats under threat. Hot yoga no better than cold. Inhalable drug mends damaged hearts

Analysis 20 YouTube Kids We can’t leave it to algorithms to decide what children watch online 22 COMMENT A messy, loud debate over depression is welcome. This “shithole” continent is not half bad 23 INSIGHT Climate doom has not been averted yet

Features 26 Living on the veg What going vegan means for your life, health and the planet 34 Peril at sea The shipping industry is in troubled waters, with sinking vessels still surprisingly common 40 Out of Arabia Ella Al-Shamahi believes our evolutionary secrets are buried in war-torn Yemen

Culture 42 Hiding in plain sight Genomic innovations are appearing so quickly, we’re struggling to identify, understand and regulate them 44 Backdoor to the future In a highly networked, increasingly insecure cyberworld, smartphones make us powerful and powerless as never before

Regulars 24 APERTURE Peekaboo pangolin hides its face 52 LETTERS A new anaerobic age 55 MAKE Pedal-powered veggie-shredder 56 FEEDBACK Astrology as a science 57 THE LAST WORD Hair of the dog?

27 January 2018 | NewScientist | 1

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More monkey business Cloning breakthrough changes less than it appears STUFFED and displayed in an Edinburgh museum, Dolly the sheep seems a distant memory – like the technique used to create her more than 20 years ago. But with the news that Chinese researchers have cloned two macaques (see page 4), Dolly suddenly feels relevant again. The long-awaited success revives not just memories of the sheep herself, but also the moral panic that greeted her. The fear then was that we had opened a Pandora’s box of cloned humans. Cloning primates seemingly brings that prospect even closer. It didn’t happen then and it probably won’t now. If anything,

the breakthrough confirms what we already knew: that cloning humans from adult cells remains a formidable technical challenge. The macaques were created from fetal cells, not adult ones. Nonetheless, there are still ethical implications. The Chinese team says its aim is to better understand harrowing human diseases. For that there is a good scientific rationale to the clones. Macaques are a better human analogue than mice, and cloning gives a level of precision that conventional breeding cannot. But is there a moral case too? Generating meaningful results would require cloning and

The veg of reason IT IS easy to dismiss veganism as a passing fad – more a celebrityfuelled fashion statement than a considered choice. The vegan lifestyle has clearly been boosted by some high-status advocates, but its credentials are more solidly established than those of most other trendy diets, such as the largely discredited “clean eating”. If done wisely, it can

have major benefits for the environment and animal welfare without affecting your health or social life (see page 26). For people wanting to live a more ethically and environmentally responsible life, quitting animal products has plenty going for it. But a word of warning: before making radical changes to your diet, seek advice from a dietician.

experimentation on a massive scale. Team leader Mu-ming Poo of the Shanghai Institute of Neuroscience is on record as saying he thinks primate research is worth it – as long as appropriate ethical standards are applied. In reality, however, the creation of clones doesn’t alter the ethical equation. The procedure is still inefficient and legions of cloned macaques appear unlikely; meanwhile, China has embarked on a major research programme using conventionally bred and GM primates. The ethical debate is very much alive, but clones are not where the action is – at least for now. ■

It is theoretically possible to get all the nourishment you need from a plant-based diet, but without knowledge and discipline it is also possible to sleepwalk into nutritional deficiency. And if you believe veganism is the right thing for you and want other people to change their diets, arm yourself with knowledge about the benefits and pitfalls. Veganism should be an informed and evidence-based choice, not a sashay onto a bandwagon. ■ 27 January 2018 | NewScientist | 3

NEWS & TECHNOLOGY

Say hello to cloned monkeys Clones will herald new therapies, but will they be accepted, asks Andy Coghlan

QIANG SUN AND MU-MING POO, CHINESE ACADEMY OF SCIENCES

MEET Zhong Zhong and Hua Hua, the world’s first monkeys cloned using the technique that gave us Dolly the sheep. The female long-tailed macaques represent a technical milestone. It should make it possible to create customisable and genetically uniform populations of monkeys, which could speed up treatments for diseases such as Parkinson’s, Alzheimer’s and cancer. But the breakthrough will inevitably raise fears that human cloning is closer than ever. The monkeys hold such huge potential because they all inherit exactly the same genetic material, says the Chinese team that cloned them. This would enable scientists to tweak genes the monkeys have that are linked to human disease, and then monitor how this alters the animals’ biology, comparing it against animals that are genetically identical except for the alterations. It could accelerate the hunt for genes and processes that go wrong in these diseases, and ways to correct them, the team says. Although 23 species of mammal have been cloned since Dolly – including pigs, cats, dogs, rats and cattle – monkeys have, until now, proved resistant to the technique (see “A brief history of mammal technique used to produce Dolly cloning”, opposite). to create a theoretically limitless In 2000, researchers cloned number of clones. monkeys for the first time, but did Called somatic cell nuclear so by splitting an embryo after it transfer, the method involves had been fertilised, essentially removing the nucleus from a just producing a genetically donor egg cell and replacing it identical twin. This method can with one taken out of a cell from only be used to create a maximum another animal. of four identical animals. Now, Qiang Sun at the Chinese “This could accelerate the hunt for genes that Academy of Sciences Institute of go wrong in disease, and Neuroscience in Shanghai and ways to correct them” his colleagues have tweaked the 4 | NewScientist | 27 January 2018

An electric current is used to trick the egg into thinking it has been fertilised, and it starts to develop into an early embryo. When implanted into the uterus of a surrogate mother, the embryo will grow into a carbon copy of the animal that donated the nucleus (see diagram, opposite). Previous attempts to do this in monkeys have never progressed beyond an early embryonic stage called a blastocyst. Sun and his colleagues went

Zhong Zhong and Hua Hua, not one of a kind–

further by introducing two new ingredients to the soup of nutrients and growth factors that help cloned embryos grow before being placed into the surrogate. The ingredients – messenger RNA and a compound called trichostatin A – awakened at least 2000 genes that are vital for various stages of embryonic development, enabling

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development to proceed. The team also discovered that it is easier to clone macaques if you use cells from fetal macaques rather than adults. Zhong Zhong and Hua Hua were both created using cells destined to form connective tissue, extracted from an aborted female fetus. Altogether, 79 embryos were implanted into 21 surrogates. The pair were the only live births from six pregnancies (Cell, DOI: 10.1016/j.cell.2018.01.020). Dolly was the only success from 277 implanted embryos.

Human clones Although attempts to perform the technique using cells taken from adult macaques also produced two live animals, both died soon after birth, and one had abnormal body development. “For many cell types, reprogramming is more difficult for adult cells than for fetal cells,” says Robert Lanza, chief scientist at the Astellas Institute for Regenerative Medicine in Massachusetts, whose team cloned human adult skin cells for the first time in 2014. “That appears to be the case here as well,” he says. This technical hurdle may put to rest fears often expressed after cloning successes: that it could lead to a Never Let Me Go scenario – the science fiction novel in which human clones are created for spare organs. Post-Dolly, the Raëlian movement in California claimed it had cloned human babies. It set up a firm called Clonaid but its efforts were dismissed as a hoax. “It could be a step towards human cloning, but why would you do it?” says Peter Andrews at the University of Sheffield, UK. “In terms of human biology, it’s illegal to clone a human in Britain and many other countries, and I don’t think anyone would rationally want to do it.” The Chinese team says its focus is to use the cloned monkeys to create better animal models of

The same technique used to create Dolly the sheep has produced Zhong Zhong and Hua Hua, two long-tailed macaque clones Monkey A (fetus)

Fetal cell provides connective tissue cell

NEW STEP Add organic compounds and RNA molecules to awaken genes vital for embryonic development

Implant in surrogate

Nucleus removed

Monkey B (adult)

Adult monkey provides unfertilised egg cell

Nucleus removed

Nucleus from monkey A placed in empty egg cell from monkey B and electric current applied

Cloned animal born with the same DNA as monkey A

disease in order to accelerate medical therapies. Andrews says this concept has merit, especially given the long-standing difficulties of trying to mimic complex diseases like Alzheimer’s and Parkinson’s in mice. To date, all therapies that have treated Alzheimer’s-like symptoms in mice have failed when trialled in humans. One potential reason for the repeated failure is that the Alzheimer’s mouse model is not a close enough replica of the human

version of the disease. The most recent UK assessment Now it might be possible to on the ethics of primate research, better model Alzheimer’s in published in 2006, found cloned monkeys by knocking out “a strong scientific case for genes that have a similar role in the carefully regulated use of monkeys and humans, such as non-human primates where one that triggers the production “It may put to rest fears that of beta-amyloid plaques that it could lead to a Never Let clog up Alzheimer’s brains. Me Go scenario of creating There are issues though, says human clones for organs” Andrews. “Not least the cost of keeping primates, and that you’d need to breed many of them for it there are no other means to to be useful. You would then run address clearly defined questions into ethical problems – you can of particular importance”. see why people would object.” In 2013, the US announced plans to retire all but 50 of its 360 research chimpanzees and phase A BRIEF HISTORY OF MAMMAL CLONING out the majority of research on 1996 Dolly the sheep is born using a 2004 South Korean scientist, Woo these animals that it previously technique called somatic cell nuclear Suk Hwang, claims to have obtained supported. It is also reviewing its transfer, in which the DNA from one embryonic stem cells from cloned policies on other related animals. animal is placed into an empty donor human embryos. In contrast, China plans to egg. The two components are 2005 Snuppy, the world’s first accelerate medical therapies by stimulated with an electric current cloned dog is unveiled, also by Woo studying cloned and genetically and given nutrients that stimulate Suk Hwang. engineered monkeys. them to grow into an embryo. 2006 Woo Suk Hwang’s claims of At a conference in May 2016, 2000 First monkey cloned, but not cloning human embryos are found Mu-ming Poo of the Institute using the Dolly technique. Instead, to have been fraudulent. of Neuroscience in Shanghai a monkey embryo is split to create 2013 Embryonic stem cells are unveiled the world’s first more embryos. This method can extracted from cloned human genetically engineered monkey only be used to create a maximum embryos by Shoukhrat Mitalipov with a version of Parkinson’s of four clones. at the Oregon Regional Primate disease and presented 2001 The first attempt at using Research Center. ambitious plans to expand cloning to boost an endangered 2016 Mu-ming Poo at the Institute the use of monkeys to study species fails after a cloned bison of Neuroscience in Shanghai, China, neurodegenerative disease. called Noah dies soon after birth. unveils the world’s first genetically He made the same case in New 2001 The first cloned cat arrives, engineered monkey with a version Scientist shortly after, arguing called “Cc”, short for “carbon copy”. of Parkinson’s disease. that because monkeys are so 2004 The first cloned monkey 2018 The world’s first cloned closely related to us and have embryos are created using the monkeys using the Dolly technique advanced minds and complex Dolly technique, but none survive are unveiled in China. They are called social networks, they will tell us long enough to be implanted. Zhong Zhong and Hua Hua. much more about diseases of the brain than mice ever could. ■ 27 January 2018 | NewScientist | 5

NEWS & TECHNOLOGY

What caused freak glacier collapse? and killed nine people, all animal herders. Kääb’s team estimates that the collapse of Aru-1 released 68 million cubic metres of ice. Two months later, on 21 September, a second glacier called Aru-2 also fell apart just 2.6 km away. This time its bottom

IN 2016, two glaciers in Tibet fell apart triggering huge avalanches that caused widespread devastation. Such a collapse had only been seen once before, so the events suggested that glaciers collapse more frequently than anybody realised. But we don’t yet know which other ones are at risk. Andreas Kääb of the University of Oslo, Norway, and his colleagues have combined eyewitness reports with remotesensing images and other data to better understand how the glaciers came to disintegrate. They have also spotted the telltale signs of impending collapse, knowledge that could be used to warn people nearby. The first glacier to give way was in the Aru Range on the western Tibetan plateau. The researchers dubbed it Aru-1. On 17 July 2016, almost half of the glacier broke off in one huge chunk and went sliding and crashing down the valley. The ensuing avalanche covered more than 8 kilometres

Origin of insect wings revealed by gene editing INSECTS first evolved wings around 400 million years ago, and winged insects have thrived ever since. But how did that crucial first step happen? Biologists have debated several rival ideas for over a century, but no fossil insects with “proto-wings” have been found, so there have been no conclusions. Now two groups have used the gene-editing method CRISPR to narrow down the possibilities. Heather Bruce and Nipam Patel at the University of California, Berkeley, 6 | NewScientist | 27 January 2018

Avalanche: nine people died after the Aru-1 glacier snapped in two

XINHUA NEWS AGENCY/EYEVINE

Michael Marshall

half sheared off in two distinct chunks, totalling 83 million cubic metres. Each event was terrifyingly fast, taking just 2 or 3 minutes. The ice moved at an average speed of 20 metres per second. Kääb’s team analysed satellite photos of the glaciers taken in the months leading up to the collapses. They spotted telltale crevasses in the middle of the

looked at how insects evolved from crustaceans. Insects have six leg segments, but most crustaceans have seven, so insects lost at least one. Bruce used CRISPR to disable leg genes in a crustacean called Parhyale hawaiensis, to find which segments relate to parts of the insect body. They found this only made sense if modern crustaceans and insects had a common ancestor with eight leg segments. Modern crustaceans lost one segment, but for insects, two fused with the body, and the wings evolved from them (bioRxiv, doi.org/cjm7). Yoshinori Tomoyasu at Miami University in Ohio and his colleagues have also used CRISPR to disable the genes in P. hawaiensis that

correspond to wing genes in modern insects. He used other genetic techniques to make the flour beetle Tribolium grow wings on its abdomen, tracing which tissues give rise to them. These studies show that two tissues that are quite separate in crustaceans merge to form the wings of insects (bioRxiv, doi.org/cjnb and PNAS, doi.org/cjnc). “Two distinct tissues are cooperating to form one structure,” says Tomoyasu. This “dual origin hypothesis” was first proposed in

“Maybe wings evolved in tree-living insects that glided to safety when threatened”

glacier, which had formed over that time period and were roughly where it split in two. They also looked at seismometer data in the area to check that no earthquakes might have set off the collapse (Nature Geoscience, doi.org/cjnm). So are glaciers breaking up more often? The world is warming as a result of our greenhouse gas emissions, and this has caused glaciers around the world to retreat. Intuitively, then, it would make sense if some disintegrated as a result, but Kääb says it is too early to tell. “Some of the factors that we’re pretty sure were involved in the collapses… are changing through climate change,” he says. However, some factors like the type of bedrock are not, and they are just as influential in the potential break-up of a glacier. It is also impossible to tell which areas are more at risk. “They could happen in places it didn’t happen before and nobody was thinking it could happen,” says Kääb. He hopes local people will come forward with stories of collapses, which will help scientists. The good news is that warning signs seem to be visible in satellite imagery. “We know now, if we see specifically a special type of crevasse, in our heads alarm bells go,” says Kääb. ■

1916, but until recently it was just one of several rival ideas. The new studies, plus a fossil insect described in 2017, support the dual origins hypothesis, but Bruce’s study suggests the process was more complex than originally envisaged. “The papers fairly conclusively show the developmental origins of wings in insects,” says Morgan Jackson at the University of Guelph in Canada. However, they don’t tell us why wings evolved. One idea is that wings evolved in insects that walked on water and harnessed the wind to sail across the surface. Alternatively, maybe wings evolved in tree-living insects that glided to safety when threatened. Michael Le Page ■

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THREE of the strangest cosmic signals that we detect on Earth may come from the same place. Ultra-high energy cosmic rays, high-energy neutrinos and powerful gamma rays could all be born in the chaos of a black hole jet. Ultra-high energy cosmic rays have energies millions of times higher than anything we produce in accelerators on Earth. No one knows for sure where they originate. The same is true for neutrinos and gamma rays with extremely high energies. Now, Ke Fang at the University of Maryland and Kohta Murase at Pennsylvania State University have found a way to get all three types of particles from a single source (Nature Physics, doi.org/cjqn). They suspected the particles might share a common origin because they all bring about the same amount of energy to detectors on Earth. “Each particle has a different energy, but somehow the total energy supply from each type is very comparable,” says Murase. “This is very weird, and it implies that they might have a physical connection.” Murase and Fang simulated a cosmic ray’s path from the centre of a cluster of galaxies to our detectors. Protons that make up cosmic rays are accelerated by jets of plasma shooting out of supermassive black holes. The resulting ultra-high energy cosmic rays bounce around within a cluster of galaxies, smashing into clouds of gas and other matter. These interactions create particles called pions, which then decay into neutrinos and gamma radiation. The cosmic rays, along with their offspring, eventually leak into intergalactic space, where some of them make their way towards Earth. Kim Weaver at NASA’s Goddard Space Flight Center says this solution to the mystery is plausible. “If you get the high-energy cosmic rays produced in the jets, you’re also going to get the others,” she says. “It’s an elegant solution.” Leah Crane ■

FRANK CHMURA/MIRA/PLAINPICTURE

Black hole jets have the oddest offspring

Code-cracking AI could unlock robot translation SECRET code or foreign language? another part determines For machines, it might not matter. whether the result makes sense Without any prior knowledge, an based on what it has learned artificial intelligence algorithm about English. If it doesn’t, the has cracked two classic forms of algorithm updates its next encryption: the Caesar cipher and guesses accordingly. This process Vigenère cipher. As translating was then repeated thousands of languages is similar to decoding times, until the GAN reached near a cipher, the approach may perfect accuracy on coded text improve translation software. generated by the Caesar cipher, To break the ciphers, Aidan named after Julius Caesar, who Gomez and colleagues at the “One part of the system University of Toronto and tries to guess the cipher Google used a type of algorithm and the other bit checks called a generative adversarial if the results make sense” network. The GAN started with no knowledge of ciphers or language, used it, and the Vigenère cipher, but by analysing thousands of invented in the 16th century English sentences and lines of (arxiv.org/abs/1801.04883). coded text, it was able to start The GAN broke the ciphers by switching between the two. The learning a technique similar to texts were in no way related. For frequency analysis. This method instance, the GAN could have relies on knowing how often each started with Alice’s Adventures letter appears in a language and in Wonderland in English and To Kill a Mockingbird in cipher text. then trying to match all the letters After analysing the texts, one by looking at the frequencies they part of the algorithm makes crop up in the cipher text. For guesses about the cipher and example, “e” is the most common

letter in English, occurring nearly 13 per cent of the time. Whatever “e” corresponds to in the cipher text should also appear with a similar frequency, giving a clue on how to break the code. For frequency analysis to work effectively, you need a lot of text to ensure accurate frequencies. But this is rarely available when intercepting secret messages, so the method is often more thought-provoking than useful at cracking actual codes. “For cryptanalysis, their results are way behind current achievements,” says Bernhard Esslinger, who runs an opensource code-cracking project called CrypTool. “But for automated translation of human languages, this could be interesting.” When learning to translate, it is usually easy to get plenty of examples of the two languages: just raid a library or scrape text off the internet. The tricky bit is working out how to switch between the two. The best current translation software learns from pairs of translated sentences. For example, Google Translate originally learned to translate between French and English by analysing thousands of professionally translated documents from the United Nations and European Parliament. But such accurate translations don’t exist for many language pairings. So translation engines normally use English as a stepping stone, first translating to English and then to the actual target language. As the new approach doesn’t require paired sentences, the stepping stone could be ditched. This process, called unsupervised translation, is something that Facebook and Google are also exploring. “Unsupervised translation is super-hot right now,” says Gomez. “It’s not just an interesting idea, it’s getting really impressive results.” Timothy Revell ■ 27 January 2018 | NewScientist | 7

NEWS & TECHNOLOGY cost hundreds of thousands of dollars, compared with millions for a satellite. “We think this has the potential to be a game changer for us,” says US admiral Kurt Tidd, commander of US Southern Command, which handles US military operations in

WORLD VIEW

“Images taken from the Stratollite are detailed enough to distinguish a pickup truck from a car”

Spy balloons for catching pirates David Hambling

UP, UP and away! High-altitude balloons called Stratollites might soon be giving the US military and NASA permanent and relatively low-cost eyes in the sky over any part of the planet they want. Developed by US firm World View, Stratollites are uncrewed hydrogen or helium-filled balloons that tour the stratosphere at between 10 and 46 kilometres up, with cameras and sensors on board. As the wind in each layer of the stratosphere blows in a different direction, a Stratollite’s path can be changed simply by moving to a different height and hitching a ride. The balloons are controlled from the ground. World View has used dozens of flights to refine the computer models and algorithms used to move the balloons. Along the way, the company claims to have carried out the biggest controlled altitude-change manoeuvre ever by a balloon, switching nearly 8 | NewScientist | 27 January 2018

8 kilometres in one sweep. The firm aims to have balloons that can permanently linger over a very small spot, by continually adjusting their height, with onboard solar arrays providing all the power they will need. “Multiple times we’ve demonstrated the ability to stay within a very tight radial area – under 50-kilometre radius for over 24 hours,” says

Unlike spy satellites, Stratollites could linger over one spot–

Andrew Antonio, World View’s director of marketing. The firm released images from one Stratollite this month with a resolution of half a metre. This is enough to distinguish a pickup truck from a car, and is comparable to high-quality commercial satellite imagery. Current spy satellites revisit a given point less than once a day, but a Stratollite can theoretically keep watch 24/7. It will also be cheaper: Antonio says that a onemonth Stratollite mission will

BALLOON MANIA THROUGH THE AGES 1670 Francesco Lana de Terzi, an Italian priest, designs a “flying ship” lifted by four copper spheres with all the air sucked out, making them lighter than air. Unfortunately, for the spheres not to collapse they would need to be so thick that the ship would be too heavy to take off. 1783 The first successful crewed balloon flight takes off from the Palace of Versailles in France. Two years later Jean-Pierre Blanchard crosses the channel from England to France in a balloon filled with

hydrogen that had flapping wings for propulsion. The journey took two and a half hours. 1937 Moments before landing, the Hindenburg airship burst into flames. Thirty-six people died and public confidence in hydrogen-filled airships disintegrated. 2018 Airships are rarely used for transport, but are still inflated for geological surveys, filming events and advertising. More uses, such as Google’s Project Loon, are on their way (see main story).

Central and South America and the Caribbean. Southern Command has been testing Stratollites since last August, and is interested in using them for combating drug trafficking and piracy in remote areas, something it currently uses drones for. Once deployed, Stratollites and drones can both be spotted from the ground by a keen observer, but whereas drones are noisy, Stratollites are silent. NASA is also testing the balloons. The agency has operated stratospheric balloons for decades to monitor everything from Earth’s surface to cosmic rays, but once the balloons are in the sky, the direction of travel isn’t controllable. Alan Stern, who leads NASA’s New Horizons mission, which completed a fly-by of Pluto last year, is a co-founder of World View. Alphabet, Google’s parent organisation, has its own stratospheric balloon project called Project Loon. It plans to use the balloons to provide mobile communication in remote areas. Last year the company deployed balloons to provide mobile phone communications in Puerto Rico after Hurricane Maria destroyed infrastructure. Steering Stratollites isn’t always going to be easy, however. In some places winds may blow predominantly in one direction, says Neal Butchart at the UK Met Office’s Hadley Centre. “Success is likely to vary with the latitude band and hemisphere the balloon is flying in,” he says. ■

NEWS & TECHNOLOGY

What makes your job so stressful suggests that the level of independence a person has, and the amount of support they receive from colleagues and bosses, determines how stressful a job is. The other that the effort a person puts into work, versus how much reward they get back, is more important. To investigate these ideas,

DO YOU give your all to your job but get little recognition? A study of workplace stress suggests that throwing yourself into work that you love, but not receiving appropriate reward, is a toxic cocktail for biological stress. Leander van der Meij, now at Eindhoven University of Technology in the Netherlands, and his colleagues have discovered this by studying people’s cortisol levels. This hormone is released in times of stress, helping prepare the body for “fight or flight” by increasing blood sugar levels and slowing down digestion, for example. The response can be helpful in the short term, but chronic stress can lead to health problems, such as infections and diabetes. To investigate whether certain workplace conditions might cause this kind of damaging stress, the team analysed cortisol levels in hair samples from 172 volunteers. There are two leading ideas about what affects people’s stress levels at work. One hypothesis

Bitcoin currency dominated by a few big players CRYPTOCURRENCY seems to be selling out. Bitcoin and other digital currencies were designed to circumvent the centralised control of big banks and instead be managed by their networks. But now they are growing similar to the very institutions they are trying to sidestep. Decentralisation is key to cryptocurrencies, because there is no Federal Reserve or European Central Bank to lend legitimacy to the cause. 10 | NewScientist | 27 January 2018

people who have particularly high workloads and long hours (Psychoneuroendocrinology, doi. org/cjcr). “What’s dangerous is if you don’t get compensated,” says van der Meij. “When you like your job and want to do well, but don’t get promoted or a pay rise, that cocktail leads to high cortisol.” Meij suspects that the longterm consequences of this could be dangerous. “It may be good that cortisol levels are higher in the short term – it may help them cope with the workload,” he says. “But we don’t know if, in the longer term, it leads to disease.” Stress levels in people working normal hours weren’t related to either idea, perhaps because they weren’t stressed enough to detect a relationship, says van de Meij. “Hair cortisol is a good marker of chronic stress,” says Kymberlee O’Brien at Worcester Polytechnic Institute in Massachusetts. Long term, you might expect to see exhaustion, depression and being more vulnerable to sickness, as well as lower well-being and life satisfaction, she says. “Employees should be able to see that their input is worth something,” says van der Meij. “As an employer, you have to ensure that they have the prospect of opportunities, especially if they are committed and do a lot of work.” ■

With bitcoin, the top four miners control more than half of the computational power of the bitcoin network, called the “hash share”. With ethereum, a well-established cryptocurrency that uses smart online contracts, more than 60 per cent of the computational power is controlled by only three miners. These may be individual miners or groups of people who share their processing power. This is dangerous, because any person or group with a hash share

of 51 per cent or more could potentially game the system by either censoring other users’ bitcoin transactions – making sure that they can’t send or receive currency – or by double-spending their own coins, according to Garrick Hileman at the University of Cambridge. The effective result is a centralised currency, but controlled by anonymous strangers instead of a government. “If it turns out that just five people can take over the coin and censor transactions, then I would want to know who those people are and be on good terms with them because they could basically freeze my coins,” says Sirer. Leah Crane ■

MASKOT/PLAINPICTURE

Jessica Hamzelou

van der Meij’s team compared the levels of cortisol in 91 people who work a typical 9-to-5 week, with those in 81 people doing training programmes, such as MBAs, alongside their day jobs. These people have more to do, work longer hours and also study in their spare time, says van der Meij. The participants also filled in a survey on work experiences over the prior three months, including rewards like pay rises and praise. Van der Meij’s team found that effort versus reward seems to be the biggest determinant of workplace stress – but only among

Instead, decentralised networks authenticate transactions so no individual user has the power to manipulate the process, but everyone has the power to check it. Emin Gün Sirer at Cornell University in New York and his colleagues monitored the bitcoin and ethereum networks from 2015 to 2017 to see how decentralisation was faring. “There is a lot of noise made about decentralisation, and then when you look at it, it’s not all that decentralised,” Sirer says. On top of this, bitcoin has halved in value since last month, with other cryptocurrencies having similar declines.

“The result is a currency controlled by anonymous strangers instead of a government”

NEWS & TECHNOLOGY

NASA/GSFC/SDO

The people who name smells as easily as colours

Stellar blasts that could cook up life Leah Crane

formed some building blocks for life on Earth and Mars, but most probably came from the sun’s UV radiation and other pathways (The Astrophysical Journal, doi.org/ cjhf). “On Earth or Mars, [flares are] a relatively small contributor to prebiotic molecules, 10 or 20 per cent, but on planets orbiting other stars it could be a major contributor,” says Loeb. Many of the exoplanets that look most promising for life orbit small, cool stars called red dwarfs. Because these stars emit less UV radiation but flare often, worlds

PLANETS blasted with stellar flares could be delicately balanced between nurturing life and killing it off. While such eruptions of high-energy particles can cause biological damage and chip away at a world’s vital atmosphere, they might also kick-start the stuff of living things. There are a few ways for a young world to come by the energy required to forge simple atoms and molecules into complex organic compounds: heat from impacts, volcanoes, “UV blasts can seed life. radioactivity or even ultraviolet But if a planet already has radiation from starlight. life, they can kill it. It’s a By simulating a solar flare double-edged sword” hitting young Mars, Avi Loeb at Harvard University and his colleagues have now shown like Proxima Centauri b could how these bursts could also cause be on the receiving end of blasts such transformations. Stellar that build organic molecules. flares, for all their danger, can “In some situations, life provide energy to turn simple doesn’t exist, and then this ubiquitous molecules like carbon bombardment creates all these dioxide and nitrogen into amino organic compounds that can acids, aromatic compounds – turn into life as we know it,” says and the nucleobases in DNA. Dimitra Atri at the Blue Marble The team found that protons Space Institute of Science in from solar flares could have Seattle, Washington. “But if there 12 | NewScientist | 27 January 2018

are already organisms there, this same bombardment can kill them. It’s a double-edged sword.” The effect on existing life also depends on whether the planet has an atmosphere. Air could stop “starter” particles from reaching the planet’s surface, but once life is there, air can stop water on the planet’s surface from sublimating away into space. The same bombardment of particles can also destroy an atmosphere. “On Mars, for example, there might have been life prior to stripping the atmosphere,” says Loeb. “It could be one after the other: the energetic particles first allow life to form, and then destroy it.” There is a gentler way solar flares can help complex molecules assemble on a world with an atmosphere. Loeb’s team suggests that the flares’ particles could also pour energy into the air, triggering electron “avalanches” that give rise to lightning. When lightning reaches the ground, it discharges a burst of energy that can fuel the formation of organic molecules. Still, the planet’s immediate environment is the most important factor in figuring out whether it can host life. If a planet has a sweltering surface and no atmosphere, chances for life are not high, regardless of how many amino acids it has. ■

WHAT’S that smell? Most of us can’t name many, but it seems huntergatherers are better at it than anyone else. It could be that, to survive in dark tropical forests, they have become adept at sniffing out fruit, prey, predators and each other – and honed their vocabularies to suit. By contrast, while Westerners can discriminate between over a trillion smells, they have few words to describe them consistently. Most English-speakers know what “purple” is, but are fuzzy on “acrid”. Asifa Majid of Radboud University in Nijmegen, the Netherlands, and Nicole Kruspe of Lund University in Sweden studied two native groups on the Malay peninsula in South-East Asia. The Semaq Beri rely on hunter-gathering, while the Semelai are mostly horticulturists. Although they have different ways of life, the two groups share the same environment and speak closely related languages. Majid and Kruspe asked members of each group to name 16 smells and 80 colours. Twenty hunter-gatherers and 21 horticulturists took the tests. The smells included leather, turpentine, garlic and fish. “We didn’t know in advance what the ‘correct’ answer would be in each language, which are both non-written,” says Majid. So the pair created a “codability” score that reflected how many people gave the same answers for each smell and colour. The score would be 0 if everyone in a group gave a different name, and 1 if all responses matched. The hunter-gatherers were better at giving the same answers for smells. Their average codability score was 0.26, versus 0.06 for the horticulturists. By contrast, the horticulturists beat the hunter-gatherers on naming colours, with 0.46 to their 0.3 (Current Biology, doi.org/cjm5). It may be the Semelai’s embrace of horticulture has led them to rely less on smell, says Majid. Andy Coghlan ■

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NEWS & TECHNOLOGY

We ditched fate to make dice fairer period. That may mean that players in Roman times thought that other forces were mostly at work in determining the outcome of a roll.” If the gods controlled the roll, why worry about unfair dice? By the 15th century, gamers wanted symmetrical dice. But what really interested Eerkens is how the numbers were arranged. There are many ways to place the

THE dice used by gamblers in northern Europe became much more fair about 600 years ago. The pattern on the faces also changed. These two trends might reflect a growing awareness that bets were decided by chance, not by gods – even though probability theory was centuries away. Archaeologists often find dice, but rarely study them in detail. Now Jelmer Eerkens at the University of California Davis and Alex de Voogt at the American University of Natural History in New York have examined 110 dice from sites in the Netherlands. Modern gamers wouldn’t like the earliest, Roman-era dice, which are around 2000 years old. About 90 per cent are asymmetrical and wouldn’t roll randomly. Only from about AD 1450 were most dice more or less symmetrical. Medieval Europeans may have been increasingly aware of the importance of chance. “People in Roman times could make symmetrical dice, and they often did,” says Eerkens. “But there is a much higher percentage of nonsymmetrical dice in the Roman

Testosterone may make you a metal head IF YOU’RE partial to a good power ballad, testosterone may be influencing your music tastes. We know that personality seems to be linked to music genre preferences, but Hirokazu Doi of Nagasaki University, Japan, was keen to find out if a person’s hormones shape their tastes too. Testosterone, for example, has been linked to aspects 14 | NewScientist | 27 January 2018

Dice have changed drastically since Roman times

PRISMA ARCHIVO/ALAMY STOCK PHOTO

Colin Barras

numbers 1 to 6 on a die, and several are seen in Roman dice. However, between the years 1250 and 1450, one arrangement dominated. Of 41 dice, 37 have 1 opposite 2, 3 opposite 4 and 5 opposite 6. This configuration is called “primes” because opposite faces add up to prime numbers. Then, in 150 years, primes died out and was replaced by the modern arrangement: 1 opposite 6, 2 opposite 5 and 3 opposite 4. This is called “sevens”, because numbers on opposite faces

of personality such as extraversion and also affects brain regions involved in experiences we find rewarding, so could it play a role in music taste? To find out, Doi’s team recruited 37 male and 39 female volunteers – most of whom were students – and played them excerpts from 25 littleknown pieces of music. Each person had to rate how much they liked the snippets on a 19-point scale, as well as providing a saliva sample, which the team used to measure their testosterone levels. They found that male volunteers with higher testosterone tended to

prefer kinds of music the team had classed as “unsophisticated” – for example, soft rock or heavy metal. Male volunteers with lower testosterone levels were much more likely to opt for classical music and jazz – genres the team call more sophisticated. No such link was found in the women. This is the first evidence of a biological basis for music preference, says Doi (Personality and

“Men with high levels of testosterone were more likely to prefer so-called ‘unsophisticated’ music”

always add up to 7. When Eerkens and de Voogt looked at UK dice, they found a similar shift from primes to sevens, from the 1450s (Acta Archaeologica, doi.org/cjmv). A standard arrangement may have been a way to check a die. “I think it’s easier for players to quickly inspect the die, to make sure it’s up to the standard, if there’s an easy pattern to remember,” says Eerkens. “Primes and sevens are easy ones.” The rise of the sevens design might be another sign of growing demand for symmetrical dice. The primes configuration might have become unpopular because it was thought “unbalanced”: it has 1 opposite 2 – adding up to 3 – and 5 opposite 6 – adding up to 11. The sevens configuration is balanced in the sense that opposite faces always add up to seven, which may have been thought to make it especially likely to roll fairly. This hints that medieval Europeans – particularly gamblers – were thinking about factors governing the outcome of rolls long before mathematicians like Blaise Pascal grasped how probability works. “It does seem reasonable that, as dice design became more ‘regular’, successful players were better able to see patterns in play that might have led to early probabilistic thinking,”says Edward Packel at Lake Forest College, Illinois. ■

Individual Differences, doi.org/ch78). Other studies have found that men with high testosterone are more likely to act rebelliously. It is possible that young rebels opt for heavy metal and soft rock because their parents may not approve of it, says Doi. “Independent of biology, the social environment and education of the participants, as well as the influence of their peers, parents and teachers are extremely important,” says Urs Nater at the University of Vienna, Austria. “Testosterone is probably one tiny aspect of what constitutes music preference.” Jessica Hamzelou ■

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IN BRIEF Drug spray to keep heart healthy

Hot yoga’s sweaty heat not all it is cracked up to be HOT yoga may just be a waste of effort, offering little benefit over similar yoga at a normal temperature. Most forms of yoga are thought to aid relaxation and muscle strengthening. But hot yoga, which typically involves going through a tough 26 poses in a warm and humid room, also makes people sweat intensely – which

a week, while a similar group of people did no yoga at all. Both yoga groups showed improvements in the health of their blood vessels compared with the control group. However, hot yoga was no better for this than the room temperature version. All other health measures, such as blood pressure and cholesterol levels stayed the same across the three groups (Experimental Physiology, doi.org/cjh4). Hot yoga did have one hint of a benefit though. All groups stayed about the same weight through the study,

some take as a sign that it’s better for you. To find out if this is true, 33 middle-aged adults who were previously sedentary did a three-month course of either hot yoga or yoga of a similar pace and difficulty but at a normal temperature. They all did classes three times

but those who did hot yoga had an average reduction in the percentage of their body that is fat of 1 per cent. This may be too small to have a meaningful impact on people’s health, says Stacy Hunter of Texas State University, who carried out the study.

Planet-eating stars could shine bright STARS like the sun don’t last forever – they eventually expand and envelop the inner members of their planetary systems. A new study suggests that as a star begins to die and slowly expands outward, it would temporarily light up as it eats the worlds it hosts (The Astrophysical Journal Letters, doi.org/cjhc). If this turns out to be the case, we could potentially catch a star

in the act of preying on a planet and learn about how the eventual death of our solar system may play out. Some day, the sun will expand. Mercury and Venus will be toast, and Earth is likely to be a goner too, enveloped in the dying star. A planet like our own wouldn’t cause its star to make much of an observable fuss. But in other solar systems, the larger, gas giants that

orbit near their star could cause a more pronounced change in brightness. However, it would be short-lived, says Melinda SoaresFurtado at Princeton University, who collaborated on the study. One other potential method to find a feasting star is to look for disturbances in its rotations. As it devours a planet, a star could spin faster. “This ‘spin up’ effect is observable and lasts longer than the luminosity ingestion signature,” says Soares-Furtado.

A FEW deep breaths could prevent the heart deteriorating after a heart attack, thanks to an inhalable drug. The drug is a spray of nanoparticles, which are small enough to be absorbed through the lungs’ air sacs and into the bloodstream. The blood travels straight to the heart, where the nanoparticles release the drug. To test it, the researchers gave the drug to mice whose hearts were injured to mimic heart failure. They measured heart health by examining the proportion of blood ejected by the left ventricle – a chamber of the heart – every heartbeat. When 10 of the mice were given the spray, this measure rose by an average of 15 percentage points (Science Translational Medicine, doi.org/cjh6). “[The heart] recovered almost completely,” says Michele Miragoli of the University of Parma in Italy.

Babbling bots are better team mates ARTIFICIAL intelligence can beat humans at games such as chess and Go, but what we really want is for AI to work with us, not against us. The key may be a little chit-chat. A new algorithm doubled the rate of cooperation between humans and AI across 472 games by adding short snippets of conversation known as “cheap talk”. The games were two-player interactions such as the prisoner’s dilemma, where participants repeatedly choose from two options with the overall outcome dependent on the other player. Cooperative AI will be useful everywhere, says Pedro Domingos at the University of Washington, including in self-driving cars, the workplace and home robotics. 27 January 2018 | NewScientist | 17

IN BRIEF

DO ANIMALS get bigger as the climate they live in gets colder? A classic idea says they do, suggesting climate change will alter animal body size. But now a study of nearly 274,000 individuals from hundreds of species has challenged the idea. Bergmann’s rule, stated in 1847 by anatomist Carl Bergmann, says an animal’s size depends on the temperature of its habitat. Smaller members of a species are found in hotter parts of the species’ range and larger ones in colder climes. For example, moose are supposed to be larger in the north of their range. The rule has been used to explain body size patterns in fish, reptiles, birds and even humans. The idea is that having more body volume per unit area of skin helps animals stay warm when in cold places. Now Kristina Riemer at the University of Florida and colleagues say the rule is wrong. They compiled data on 952 species. Only 14 per cent obeyed Bergmann’s rule, while 7 per cent did the opposite. Most showed no pattern at all (eLife, doi.org/ch8d). “Past studies that confirmed Bergmann’s rule were mostly looking at just a few species at a time, over only small areas, or were

DESIGN PICS INC/ALAMY STOCK PHOTO

data limited,” says Riemer. “We only recently have access to these huge museum data sets and the tools to work with them.”

18 | NewScientist | 27 January 2018

Trick of the light makes an exoplanet mirage SOME exoplanets around red giant stars may be no more than an optical illusion. One way to find an exoplanet is to measure changes in its star’s velocity as the orbiting planet makes the star “wobble” back and forth. Those movements are too small to detect directly, so they are found by looking for how they affect the colour of the star’s light. William Cochran at the University of Texas at Austin and his colleagues examined years of data from four observatories to characterise the wobble of a red

giant star called Gamma Draconis that is 154 light years away. From 2003 to 2011, the star’s wobbly signal seemed to indicate that it had a single planet with a mass at least 10 times that of Jupiter, orbiting once every 702 Earth days. But from 2014 to 2016, the wobble disappeared. It then reappeared in 2016, although it was out of sync with the previous signal. At the time, astronomers thought this might be caused by the star having two planets with similar orbits. Cochran and his team found

that simulations of such a twoplanet system were unstable: the planets would have to be too close together and they would jostle one another out of their orbits (arxiv.org/abs/1801.05239). The probability of the worlds staying in their respective lanes was just 1 to 2 per cent. Instead, the changes in light were probably due to huge sunspots or ripples in the star’s plasma atmosphere, says Cochran. This may raise questions over a small percentage of recently found exoplanets, he says. COURTESY OF NICOLAS GALVEZ

Animal body size breaks the ‘rule’

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Taking CRISPR to a whole new level THE CRISPR genome-editing method may just have become even more powerful. Uri David Akavia’s team at McGill University in Canada has managed to repair mutations in 90 per cent of target cells using the technique – the best success rate yet. CRISPR is great at disabling genes, but using it to fix them is much harder because this involves replacing a faulty sequence with another. This typically works in less than 10 per cent of target cells. To make the process more efficient, Akavia’s team physically linked the replacement DNA with the CRISPR protein that finds and cuts the faulty sequence (bioRxiv, doi.org/cjh5). This ensures that the replacement DNA is there ready to be slotted in once the cut is made. “We’ve taped the [replacement] text to the scissors,” says Akavia. The highest efficiency rate reported so far by other teams exploring similar approaches is 60 per cent, so the new method could be a big step forward. It now needs to be tested in a wide range of cells to confirm it is generally applicable. If it proves to be, the technique could help tackle almost all inherited diseases.

No country for small cats ONE of the world’s smallest wild cats is on the road to extinction, despite being more resilient than most. Güiñas (Leopardus guigna) live in Chile and are the smallest cats in the Americas. Their numbers are in decline, with perhaps just 10,000 adults left. Nicolás Gálvez of the University of Kent, UK, and his colleagues wanted to know why. Using questionnaires, camera traps and remote sensing, the team found that the main threat to the cats is a change in the way farms are run. Big farms are being split into smaller units, bringing in more people.

Unlike jaguars, güiñas can tolerate losing 80 per cent of their habitat and can even live on intensive farms. However, as farms splinter and human populations grow, people may persecute the cats more. While they mostly catch moths and rodents, they also like chicken, so people kill them to prevent attacks on poultry. Of the farmers surveyed, 10 per cent admitted killing güiñas (Journal of Applied Ecology, doi.org/cjnh). The güiña “requires patches of forest to remain in agricultural landscapes for it to survive in the long term,” says Gálvez.

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ANALYSIS YOUTUBE KIDS

Child’s play? YouTube is the top source of video content for kids of all ages. So why is there so little control over what they watch, asks Chris Baraniuk LOGAN PAUL is a broadcaster with an audience of almost 16 million people, but until recently, you had probably never heard of him. Paul sparked controversy earlier this month after uploading a YouTube video of himself gawking at a body in Japan’s Aokigahara forest, which is known for the high number of suicides that have occurred there. The video was viewed millions of times before it was taken down. Paul has since apologised and 20 | NewScientist | 27 January 2018

YouTube has cut some of its business ties with the star, who is one of the most popular personalities on the site. It has also changed the way it monetises some videos. Paul’s large audience of children and teenagers made the incident all the more worrying. “Logan, you’re still my hero,” said one young fan at the end of a much-viewed reaction video. But this is not the first time YouTube has faced criticism for the level of

oversight it applies to content aimed at young people. Should we expect the world’s largest video platform to do more? It is a question increasingly in need of an answer, considering that YouTube is now the number one place where kids of all ages consume video content. Nearly half of 3- to 4-year-olds in the UK watch content on the site, according to the media regulator Ofcom. Viewing figures rise with age and 90 per cent of 12 to 15s

watch YouTube videos. Among this age group, it is a better known brand than the BBC and ITV (the UK’s largest traditional broadcasters), and Netflix. Three years ago, YouTube decided to target this growing audience more directly with a new app, YouTube Kids, offering a selection of content automatically picked from the main site. “The app makes it safer and easier for children to find videos on topics they want to explore,” declared a

For daily news stories, visit newscientist.com/news

YouTube blog post about the app. It hasn’t quite worked out that way. YouTube Kids is riddled with material that would never be shown on children’s TV, says UK presenter Ed Petrie, who has worked for Nickelodeon and CBBC, two children’s channels. He points to a video on YouTube Kids in which a man throws a dish of boiling water into the air on a very cold day, turning it into snow. “There’s absolutely no way Nickelodeon or CBBC would ever show someone doing that without an awful lot of caveats and someone explaining it’s dangerous,” he says. This sort of video, without profanity, nudity or other obvious red lines, is exactly the kind that might not be picked up by an algorithm.

Watch the algorithm But some have found more disturbing content on YouTube Kids in the past. In November, a widely shared essay by writer and artist James Bridle highlighted the presence of upsetting and violent parodies of children’s cartoons on the app. Petrie believes YouTube has neglected its responsibilities here. He argues the site should radically change the way it monitors YouTube Kids and only provide videos that have been checked by a human moderator. “I don’t care if that means less content,” he says. “It’s just not appropriate to have software decide what’s OK for kids.” YouTube Kids warns parents that it is not flawless. “It’s possible your child may find something that you don’t want them to watch,” says a message during the app set-up. But given we have no idea how these videos are chosen, it is hard for parents to know how much they should worry (see “What should parents do?”, right). Google, which owns YouTube, declined to answer specific questions put to it by New Scientist about how its algorithms select content for children, or how

it responds to videos that have agree that some form of been flagged as inappropriate. automation is the only way “We work to make the videos in to moderate large sites, with YouTube Kids as family-friendly algorithms acting as gatekeepers as possible and take feedback that flag unsuitable content to be very seriously,” says a Google checked by humans. But if we are spokesperson. “Flagged videos putting the algorithms in charge, are manually reviewed 24/7 and we should know how they work. any videos that don’t belong in “The safest thing in the world the app are removed.” would be to have someone look Opaque, algorithmic decisionat every single thing that comes making is concerning wherever through, but in reality that it occurs, but Google’s lack of wouldn’t be possible,” says Peter transparency when it comes “YouTube Kids is riddled to children is particularly with material that problematic, says Sonja Jutte would never be shown of the NSPCC, a UK children’s on children’s TV” charity. “[Self-regulation] has clearly failed to protect children from inappropriate content and Maude at content-moderating behaviours,” she says. firm Crisp Thinking, which works YouTube’s challenge is to with the likes of Disney, Coca-Cola balance an unprecedented and the BBC. volume of content with A more sophisticated approach, reasonable standards. More than he says, is to monitor the 400 hours of footage is uploaded comments posted beneath a video. to the main site every minute. The footage itself may be deemed Last month, Google announced innocuous by an algorithm, it would hire thousands more but if people are responding with human moderators in an effort outraged comments, that could be to better police hate speech, a sign that it needs to be checked misinformation and content that by a human, even if no-one has might be harmful to children. gone to the trouble of flagging the “We have welcomed that,” says video as unsuitable. Jutte. “However, that isn’t a Joshua Buxbaum at WebPurify, substitute for transparency.” another content-filtering firm, Most people in the industry says that videos can be broken

WHAT SHOULD PARENTS DO? Parents and guardians should not be expected to police all content that their child might encounter online. “I’m getting quite tired of the parent-blaming going on, saying parents should be there every minute of the day – we never said that for comics or reading books,” says Sonia Livingstone, a psychologist at the London School of Economics who studies children’s use of digital media. But given the disturbing videos that can be found on the web, parents may feel they have no choice. On YouTube Kids (see main article), parents can block videos or channels they don’t want children to see, disable search or set timers for maximum allowed screen time.

In general, though, Livingstone says parental controls on such services are “very limited”. Many parents simply hope that content-blocking software will keep their children safe. But one 2017 study of more than 500 children aged 12 to 15 found no evidence that such attempts to filter material decreased the likelihood of having negative experiences online. Livingstone says that parents shouldn’t get upset if they see their child watching something inappropriate. Instead, she suggests that it is much more productive to discuss the material and explore their child’s response to it when they are ready.

into a selection of frames for checking by humans. They can also be sped up to help human moderators process content more quickly. Despite this, he says the cost of checking every video safely and properly on a large site would be “astronomical”. He’s not wrong. Paying humans just $10 an hour to review new YouTube videos would cost more than $2 billion a year, almost half Google’s parent firm Alphabet’s 2017 profits, assuming they watch at regular speed. But do kids really need access to so much content? Publishers like Netflix and the BBC manage to produce hundreds of hours of safe, child-friendly videos, more than any individual could possibly watch. YouTube, of course, doesn’t even have to pay production costs – most of its creators get paid through ad revenue sharing after the video has been made. So why can’t it ensure that YouTube Kids only contains safe content, just as its rivals do? New Scientist put that question to Google, but it declined to comment. That is probably because the answer lies in Google’s long-held position that it is a platform, not a publisher, and thus merely provides an opportunity for others to distribute content. “Our mission is to give everyone a voice and show them the world,” says YouTube’s about page. To define itself as publisher might give Google an entirely new problem: accusations of censorship, because it would need to determine what content is and isn’t allowed on its services. In the messy world of adults, that’s not desirable, but for children, perhaps editorial control is exactly what is required. For Petrie, an extra safe approach, no matter the expense, will always be the only acceptable one when it comes to providing content for young viewers. “Someone like me sounds a bit like a fuddy duddy,” he says. “But it’s just a case of caring about the people who consume your stuff.” ■ 27 January 2018 | NewScientist | 21

COMMENT

Let’s talk about it The fierce debate around writer Johann Hari’s take on depression is loud, very public and welcome, says Samantha Murphy IS IT possible for a writer whose credibility has been doubted in the past to deliver a credible message now? That question hangs over Johann Hari’s book, Lost Connections: Uncovering the real causes of depression – and the unexpected solutions. In it, Hari, hit by plagiarism claims in 2011, relays stories from across the globe about things that can stand as alternatives to antidepressant medications, such as community engagement and personal empowerment. He takes aim at the theory that depression is a brain-chemical imbalance. There has been praise from those who find hope in Hari’s take. And criticism, from two camps: those who disagree with him on the basis that his book cites inaccurate statistics, is built on flimsy amounts of science and is undermined by the fact many people have benefited from

antidepressants, and those who find the content disqualified by his lack of credibility. What if I told you that they are all right? Mostly. Despite extensive study, understanding of depression is so elusive that there is no traditional biomedical approach to it yet. The concept is a broad spectrum of types, subtypes and severity. Its origins are also convoluted, with evidence for many possible roots such as genetics, gut bacteria, diet, hormones, childhood trauma, and yes, brain chemistry, among others. The answer is likely to be a complex interaction of factors and different for everyone. One thing we do know is that, globally, depression affects 300 million people and rising. The standard clinical approach is some combination of behavioural interventions, plus counselling and medication. Due to the individual nature of depression,

Africa is great, again Trump, this ‘shithole’ continent pioneered heart swaps and more, says Curtis Abraham “WHY are we having all these people from shithole countries come here?” US president Donald Trump reportedly asked. The remark apparently referred to people from Africa, Haiti and El Salvador. The African Union Mission in Washington DC, which represents member states throughout the continent, is 22 | NewScientist | 27 January 2018

demanding an apology following its “shock, dismay and outrage”. It “strongly believes that there is a huge misunderstanding” of Africa and its people by the current US administration. Indeed. Has Trump forgotten Africa’s history, contributions and modern capabilities? Has he forgotten the many millions

taken as slaves to the Americas? Or that the economic foundation of the US was built on this labour? Or, that it was the ancient Muslim scholars of Timbuktu in Mali who kept alive the knowledge of the Greeks, through manuscripts that centuries later would inform the thinkers of the Renaissance? Did Trump not know about the recent 50th anniversary of the first successful heart transplant by South African surgeon Christiaan Barnard, which took

“Has Trump forgotten the history, contributions and modern capabilities of an entire continent?”

place on the continent? The president’s outburst goes utterly against the idea that crosscultural understanding is more important than ever for global development and world peace. The problem is that under the banner of “national conservatism”, which upholds national cultural or ethnic identity over almost everything else, prominent politicians, not just Trump, have made statements and are implementing policies that are xenophobic, narrow-minded and culturally chauvinistic. They could all do with a few lessons in social and cultural anthropology.

For more opinion articles, visit newscientist.com/opinion

Samantha Murphy is a journalist based in Lancaster, Pennsylvania

“The central revelation of anthropology is that one’s cultural reality, the world in which you are born, is just one model of reality,” says ethnobiologist Wade Davis, author of The Serpent and the Rainbow. “Other cultures, outside your own are simply different ways of being and of thinking.” That’s a view Trump is unlikely to embrace. His slogan “Make America Great Again” has morphed into “Make America Hate Again”, which will only make it hated again, at home and abroad. ■ Curtis Abraham is a writer based in Kampala, Uganda

INSIGHT Climate change scenarios

CHRISTIAN ASLUND/PICFAIR

treatment is a series of trials, errors and adjustments. And that treatment may fail in up to 50 per cent of cases. With so many people experiencing a crippling disorder, often without relief, was Hari so wrong to search for something more or different? Then again, with so many lives at stake, and so much stigma and inaccurate information keeping people from even seeking help, are Hari’s critics so wrong for giving his words extra scrutiny and holding him accountable for faulty assertions and overreach? Are they so wrong to want a more credible voice for a topic so crucial for so many? No. However, the way this played out is something we can recognise as progress. For a moment, depression wasn’t something to be quiet about. It wasn’t just specialists, advocates or brave patients “breaking their silence”. It was newspapers, Twitter users, bloggers, researchers, clinicians and patients speaking their truth. The debate is unapologetic, loud, personal, emotional and so many of the points are crucial and correct for some… but not for all. Because that’s depression. ■

Globaldoomhasnot beenruledout Michael Le Page

Duke University, who studies climate sensitivity. Cox agrees. “We don’t know for sure,” he says. Yet other recent studies say sensitivity is higher. One last month put it between 3 and 4.2°C. Because studies often use different methods, it isn’t obvious why the results vary or which should be given more weight. While there is uncertainty about the upper range of climate sensitivity, nearly all major recent studies agree that low values can be ruled out. Some climate deniers claim that sensitivity

HEADLINES last week proclaimed the worst-case scenarios for climate change were “debunked” and “not credible”. As you might expect, things aren’t that simple. The stories were sparked by a study by Peter Cox at the University of Exeter, UK, and his colleagues, who attempted to work out how much warming will result from a given increase in carbon dioxide levels. Specifically, if we doubled CO2 levels in the atmosphere and waited for “Even high-end estimates the temperature to stabilise, how are likely to underestimate much would the world warm? the eventual rise in global This is known as the equilibrium temperatures” climate sensitivity, and climate scientists have been trying to work it out for decades. Hundreds of is so low we don’t need to worry studies have produced a wide range about climate change – we are now of results, which means there is a lot very sure they are wrong. of uncertainty, but the consensus In fact, even the high-end estimates says 1.5 to 4.5°C is most likely. are likely to underestimate the Cox’s study narrows this to between eventual rise in global temperatures. 2.2 and 3.4°C (Nature, doi.org/ That’s because these studies only look gcsmn4). That is excellent news if it is at the warming seen a few decades right, but it isn’t a definitive answer. after a doubling of CO2, whereas in reality it would take thousands of “This study does not set the final years for temperatures to stabilise. boundaries,” says Drew Shindell of

The issue here is that how much the world warms depends on lots of feedback effects. Some are very fast, such as changes in clouds. Others are slow, like changes in vegetation or the melting of the great ice sheets. By convention, climate scientists only include the rapid feedbacks when calculating equilibrium climate sensitivity. The argument for this is that the response over the next few decades is most relevant to policy. But in the long run there will be more warming – the “true” climate sensitivity could be 6°C or more . We also need to be cautious about studies that are based on how the climate has behaved over the past century or so, like Cox’s study. There could be surprises in store as the world warms further. And keep in mind, the worst-case scenario is the business-as-usual scenario, in which we continue to pump out C02 as we are today. The consensus is that could warm the world by 4°C by 2100, give or take 1°C. (This is a projection of the actual warming, not the sensitivity, which is a more abstract measure of the climate). If Cox is correct, that estimate is still in the right ballpark. The good news is that the world isn’t expected to stay on this highemissions pathway. Even so, CO2 levels are rising faster than ever, so there is no room for complacency. We aren’t doing nearly enough to limit warming to 2°C, even assuming Cox is right. ■ 27 January 2018 | NewScientist | 23

APERTURE

24 | NewScientist | 27 January 2018

Peekaboo pangolin THEY have been called the most hunted animal in the world, so perhaps you can’t blame this pangolin for hiding its face. Temminck’s ground pangolin (Smutsia temminckii) is found across a vast swathe of eastern and southern Africa. It has no teeth – pangolins are Africa’s ecological answer to anteaters, tearing into termite mounds and pulling out insects with their sticky tongues, as this one is doing in Gorongosa National Park, Mozambique. Its tools are tough claws that it curls under its arms when it walks. The mammal is secretive and nocturnal. While it can rely on its formidable scales for protection against hyenas and leopards – its traditional hunters – it doesn’t fare well against people after it for bushmeat or bogus medicine. The extraordinary armour is made of the same stuff as hair; burning the scales is thought in parts of East Africa to repel lions, or they can be used in “medicine”. In some areas, it is considered good luck to present a pangolin to the local chief, village shaman or rainmaker. None of this supposed luck rubs off on the animal, of course. The IUCN Red List of endangered species classifies Temminck’s ground pangolin as vulnerable to extinction, and projects a decline in population size of between 30 and 40 per cent in the next few decades. Rowan Hooper

Photographer Jen Guyton naturepl.com

27 January 2018 | NewScientist | 25

COVER STORY

Living on the veg Is veganism just a fad or should we all give up meat and dairy, asks Chelsea Whyte

I

FLUNKED out of veganism the first time because I wasn’t getting the vitamins and micronutrients I needed. I was out of balance. I went to the doctor feeling lethargic and vaguely unwell and was told I had two options: give up being vegan or start taking large amounts of nutritional supplements. I chose meat and dairy. The quantities of pills I had to take irritated my stomach and I wasn’t willing to tough it out. That was two years ago and I’d been vegan for three. Then veganism exploded into the mainstream. Celebrities from Natalie Portman and Serena Williams to Formula 1 driver Lewis Hamilton have all declared themselves to be vegan. At first I figured I had done my trial and knew where I stood. But I’ve looked into the environmental and health impacts again, and am having second thoughts. Vegans made up just 1 per cent of the US population in 2014. Three years on, an additional 16 million Americans – 5 per cent of the nation – had joined the club. In the UK, their numbers are smaller but also growing. A 2016 poll suggests that just over 1 per cent of Britons never eat meat or animal products. According to the UK Vegan Society, that’s a more than threefold increase in 10 years. The trend is hippest among 15 to 34-year-olds. Stores and restaurants have jumped on the bandwagon with “plant-powered” menus, vegan supermarket shelves and vegan farmers’ markets. In short, veganism is the new foodie movement. But is it really healthier for humans and the planet? And did I make the right choice? People cite a range of reasons for going vegan, from an opposition to animal cruelty to a desire to help cut greenhouse gas emissions.

26 | NewScientist | 27 January 2018

The basic principle is to abandon all animalderived products, particularly in food. That means no meat, fish, milk, cheese or eggs – even those laid by free-range chickens, which are still debeaked and can be packed as densely as nine birds per square metre. Most dietary vegans also avoid honey, because it is produced by bees. Ethical vegans oppose the use of all animal-derived products (see “Not just a diet”, right). For many, the dietary constraints of veganism raise genuine health concerns. Meat, fish, dairy and eggs aren’t just tasty, they also supply essential nutrients. Cutting them out can leave you in a nutritional hole. Humans evolved on an omnivorous diet, so can we really get everything we need from plants alone? The short answer is yes, sort of. If you’re considering going vegan, you will need discipline to cover all the bases. Macronutrients are easiest. Vegan fats come from things like olive oil, nuts and avocados. Carbohydrates are in high supply in fruits, grains and beans. Protein is abundant in lentils, quinoa and tofu. Getting enough of all these doesn’t necessarily mean bland menus. A burrito with half a cup each of black beans, brown rice and avocado, plus a quarter of a cup of tofu will provide you with 25 grams of protein, or about half of the recommended daily amount – and a third of your daily carbohydrates too. That said, plant proteins often lack essential amino acids present in animal-based proteins such as those found in milk, so vegans need to seek out alternative sources. Lysine, for instance, is an important building block of muscles and skin. It is plentiful in beans and >

Not just a diet To some, veganism is a philosophy not a diet. Ethical vegans oppose the use of all animal-derived products including in: TATTOOS Some inks contain glycerin from animal fat, charred animal bones or beetle shellac MAKE-UP BRUSHES Those soft bristles can come from mink, sable or even squirrel SHAMPOOS AND CONDITIONERS Animal testing is a big no-no for vegans. Even companies that no longer test on animals sometimes still use gelatin or other animal by-products SILK Silkworms are boiled alive in the process of harvesting their cocoons TOOTHPASTE Its texture comes from glycerin, which can be made from plants, but is also produced from animal fats FABRIC SOFTENERS Some contain tallow, derived from rendered fat from cattle or sheep

BRETT RYDER

27 January 2018 | NewScientist | 27

Bee slaves

28 | NewScientist | 27 January 2018

‘ E. MCGREGOR/PACIFIC PRESS/ALAMY LIVE NEW. RIGHT: ITS_AL_DENTE/OKSANA MIZINA/KIBOKA/SHUTTERSTOCK

Many vegans avoid eating honey because it is an animal product, but a bee’s contribution to our diet goes much further than that. Bee colonies are shipped from farm to farm to help pollinate vast quantities of fruits, vegetables and nuts, and maximise yields. Take almonds, for instance, a prize vegan ingredient. Trees bloom over about a week, and only blossoms that are pollinated can go on to produce a nut. To get the most out of each tree, farms hire hives of honeybees that can be trucked long distances. Migratory beekeeping, as it is called, is decidedly unvegan, but it is absolutely vital if we’re going to keep these plants producing enough nuts to feed a vegan world. Onions, cucumbers and avocados are just some of the vegetables that also rely on transported bees. Could we imagine a world in which an armada of robot pollinators release bees from the yoke? Unlikely. Bees are just too efficient and their behaviour is tricky to recreate. Although some robo-bees have been built, they’re not a practical solution on a large scale. “Can you imagine a billion robotic bees?” says Chensheng Lu at Harvard University. “How would they not collide? How would their signals not interfere?”

legumes, and other essential amino acids can be found in seeds and chickpeas. Like vegetarians, vegans don’t eat seafood, so miss out on a convenient source of the omega-3 fatty acids, which help build our cell membranes. Without these nutrients, our bodies can’t make the hormones that control artery expansion and blood clotting. They also keep our hearts beating regularly and our brains firing. If you’re habitually consuming negligible amounts of omega-3s, “that’s probably going to affect cognitive function in some way”, says David Rogerson at Sheffield Hallam University, UK. In childhood, low omega-3 levels can be associated with attention deficit disorder and behavioural problems like hyperactivity, anxiety and temper tantrums. Omega-3s have been found to help with sustained attention in adults too, and taking more is correlated with lower rates of dementia. That’s why vegans have a healthy obsession with seeds and nuts. Chia and flax seeds, walnuts and leafy vegetables contain alphalinolenic acid, an omega-3. Eating enough to meet daily recommended doses can be tricky though (see “Healthy you”, opposite), so an easier solution is to take supplements made from algae oils. Supplements can also be useful for vitamin B12. Like omega-3s, it is essential for our brains

“People cite a range of reasons for going vegan. Opposing animal cruelty is one”

to function and not getting enough can cause dementia, among many other problems. It is one of the most commonly cited nutritional challenges for vegetarians too, although one review found that B12 deficiency is more frequent among vegans.

Healthy caution Vitamin B12 is made by bacteria in the guts of some animals, like cows, and omnivores get it from eating meat. Vegans and vegetarians can fill the gap with fortified breakfast cereals. Nutritional yeast is another good source. It sounds unappetising, but actually has a pleasant, slightly cheddar-like flavour. Pregnant and breastfeeding women, as well as children, may need to be particularly aware of their diet. There have been reports of severe nutritional deficiencies and neurological and physiological disorders in children who are raised vegan. The UK National Health Service says it should be possible to get most nutrients from a balanced diet, though vegans may need to take supplements or fortified foods, and the NHS advises speaking to your doctor about getting all the nutrients you need. Without dairy, vegans must rely on green vegetables like broccoli and kale for calcium. Iodine, important for thyroid function and metabolism, can come from seaweed or cranberries. Iron is available in green vegetables, legumes, nuts and seeds. They contain a form that is harder for our bodies to use, so the US National Institutes of Health recommends that people who don’t eat meat get nearly twice as much plant-based iron as those who do. All of which goes to show why my biggest challenge when I went vegan was having to think about what I was eating far more than before. It can be hard, and occasionally lonely, to abstain from meat and dairy, simply because they are what is readily available in stores and restaurants. Having friends who shared recipes with me was essential and, in the end, I liked my new food so much that I frequently still eat vegan. It was a fuzzy sense that meat and dairy production weren’t great for the climate that made me stop eating them in the first place. Looking at the evidence now, it turns out I was right. Studies show that if we all went vegan, two of the biggest environmental problems – greenhouse gas emissions and clearing land for agriculture – would be slashed. “We use an enormous amount of the world’s land for animals or animal feed,” says Jonathan Foley, director of the >

HEALTHY YOU It is possible to get what you need from plants alone, if you’re careful

Omega-3s

Vitamin B12

Calcium

Daily recommendation: 1.1 grams (women)/1.6g (men)

Daily recommendation: 2.4 micrograms

Daily recommendation: 700 milligrams

1/3

18

or

salmon fillet (40g)

1/2

walnuts

or

5.5g

100g or 500g

enriched nutritional yeast

steak (110g)

cheddar cheese

cooked kale

Sources: Nutritics / NHS / NIH / USDA

HEALTHY PLANET If you did go vegan, your ecological footprint would shrink

Protein

Greener veg

You need 45 to 55 grams of protein a day, which you can get from…



or

Most adults in the UK eat 110 grams of meat a day, making them high meat eaters. The carbon footprint of their diet is more than twice that of a vegan

Maize Wheat Rice Fruit and veg Eggs

Land use



1 cup of cooked tofu (250g)

Your choice

Soy

2

Greenhouse gases

30g

❭ 3.5m

1 large pork chop (175g)

Dairy Poultry

0.6m2

Pork Fish from trawlers Beef

0

10 20 0 Greenhouse gases (g CO2 equivalent/kcal)

Annual emissions of a 2000 kcal/day diet (kg CO2equivalent)

2626

Medium-meat*

2056

Low-meat*

1706 1392 1056

Vegan

Alternatively, you could just choose not to take that holiday in Majorca this summer

0.05 0.1 Land use (m2/kcal)

High-meat*

Vegetarian

A medium meat eater who decides to go vegan would cut their diet’s carbon footprint by an extra 50 per cent compared with going vegetarian

SOURCE: doi.org/cjcw

1122g ❭

Vegan calories have a much smaller environmental impact than those from meat, fish, dairy and eggs

Carbon savings

Medium meat eater going vegetarian

664 kg CO2e

Medium meat eater going vegan London - Majorca - London economy seat

1000 kg CO2e 490 kg CO2e

London - New York - London economy seat

890

Average UK family car per year (7800 miles)

2300 *High meat ≥100g/day

*Medium meat = 50-99g/day

*Low meat ≤ 50g/day

Source: DOI: 10.1007/s10584-014-1169-1

27 January 2018 | NewScientist | 29

Our lives literally depend on animal products. Vaccine production often involves gelatin or eggs. While it wouldn’t be advisable to refuse vaccination in an attempt to adhere to a vegan lifestyle, it could be possible one day to manufacture some vaccines without animals. Tobacco plants have been used in experimental techniques to produce vaccines for Zika and polio. Cells from carrots, rice and maize show promise as bioreactors: cellular factories where virus-like particles can be incubated en masse. These trials are in their infancy and Stanley Plotkin, a vaccine researcher who developed the rubella vaccine used around the world, says we won’t ever be able to rely entirely on plants. “Although some vaccines can be made in insect cells or tobacco leaves, that is not possible for all,” he says. He also says it would be impossible to make vaccines without testing them in animals, which is the next step in the development process. Animals are stand-ins for humans, and it is arguably even less ethical to jump straight to testing new medical treatments on humans than it is to first trial them on animals. There is hope that we could replace the animals in this equation with organs on chips. The technology is

‘ SVETA ZARZAMORA/GETTY

nascent, but relies on human stem cells to produce organ-like systems that can then be used to test treatments and tailor medication to particular patients. Drug trials in lab mice are notoriously patchy in terms of leading to useful human medications because different species react differently to certain drugs. It is a long way off – if it is even possible – but replacing animals in drug development might result in better medicine.

California Academy of Sciences. According to the UN Food and Agriculture Organization (FAO), a quarter of the ice-free land on the planet is used to graze livestock. On top of that, a third of all cropland is used to produce additional food for them. What if we instead used that land to produce human food? Livestock eat more protein than they return for human consumption – between 3 and 20 times more. So Foley argues that one obvious way to feed billions more people is to eat more of the plants we grow, and feed fewer animals. The livestock industry is also a huge source of greenhouse gases. In part, this is because pastures and fields replace forests, which normally suck up and store carbon dioxide. In addition, like any industry, the livestock sector uses large amounts of fossil fuels, plus ruminants like cows notoriously burp methane. All told, the FAO calculates that livestock farming is responsible for 14.5 per cent of global greenhouse gas emissions – on a par with all trains, cars, ships and planes. Cows are the worst offenders, responsible for two-thirds of the total, and crucially for the vegan cause, it’s not just because of meat production. Beef and dairy cattle produce similar amounts of greenhouse gas emissions. A solution might be to switch to soy lattes.

30 | NewScientist | 27 January 2018

It takes at least 45 times as much fossil fuel energy to produce 1 kilocalorie of milk protein as it does to grow one of soy. Soy plantations are, admittedly, a driver of deforestation, but tofu and soy milk aren’t their main product. Animal feed is, says Charlotte Streck, director of the Climate Focus think tank in the Netherlands. “Even if we all replaced meat with soy, we would still have a huge decrease in soy production because so much of it is for animal consumption,” she says. In a 2017 assessment, Climate Focus found that 26,700 square kilometres of forest are cleared each year to graze cattle and grow crops to feed livestock. Soy plantations, by contrast, account for 6000 square kilometres of cleared forest each year. The bottom line is that giving up meat will massively reduce your carbon footprint, but going the extra mile to become vegan will drop it even more. If, like me, you only eat meat a few times a week, going vegan will double the emissions you cut out of your footprint (see “Your choice”, page 29). Ray Pierrehumbert at the University of Oxford has studied the environmental impact of various diets. If we are going to feed a burgeoning population set to hit 9 billion before 2050 without massive environmental

egan plates have the smallest ecological ootprint. Soy protein causes 4.5 times less eforestation than meat protein”



In your meds

Cruelty-free booze

So you’ve bitten the bullet and turned your back on steak, quiche and cheese, but still you find yourself buying meat-based products every week. It’s the dog food that’s getting to you. Some pets just can’t get the nutrients they need from a vegan diet, says Cailin Heinze, a veterinary nutritionist at Tufts University in Massachusetts. Cats and ferrets top the list. “Dogs and people can eat green leafy vegetables and carrots as a source of vitamin A, and can make beta-carotene into vitamin A,” she says. “Cats and ferrets don’t have enough activity of the enzyme that breaks down beta-carotene into the active vitamin A.” Cats also can’t make taurine – an amino acid key to vision, digestion and heart function – and it doesn’t occur naturally in plants. Companies could supplement cat food with the individual amino acids your pet would need, but powdered amino acid doesn’t taste particularly good, Heinze says. We could also leave our cats to fend for themselves outside, but domesticated cats can decimate wild populations of songbirds or other small animals, so forcing them to hunt doesn’t decrease the amount of animal suffering in the world.

Even some wines and beers are off limits for vegans. Isinglass made of fish bladders, casein from milk protein and albumen from egg whites can all be used at the end of the brewing process. They help filter proteins or yeast out of the wine or beer and leave it clearer and, some argue, better tasting. If you have ever had a hazy home brew, you’ve probably had beer that hasn’t gone through this process. Traditional brews have used isinglass for centuries. But no need to give up your Guinness quite yet. Manufacturer Diageo announced this year that it will stop using isinglass in the filtration process for the drink. Others are going vegan too. Wine-makers and brewers alike have vegan drinks available. They range from passable to downright delicious, but then so do non-vegan drinks. There’s even vegan champagne, so you can ring in a vegan New Year in style.

Instead of making non-vegan animals conform to a vegan ideal, perhaps it would be a better idea to keep as pets only animals that are naturally vegan. Heinze says that while dogs can survive on a vegan diet, it would have to be designed very carefully to make sure they are getting all the nutrients they need. Alternatively, “we could just start having miniature horses instead of dogs and then we’ve solved it”, Heinze muses. Pigs, which are also quite clever, can get by on plants alone. And rabbits are as furry and cute as cats.

BAOBAO OU/GETTY

What about your furry friends?

degradation, we will have to do it with plants, he says. Which raises a potential problem with growing veganism. Vegan foods, like coconut oil and nut butters, frequently aren’t locally grown. If a significant portion of the population were to abandon meat and dairy, more plants would have to be moved around, which would offset some of the carbon savings of more people quitting meat and dairy. Sure, but not much, says Pierrehumbert. He points to a report that broke down the emissions over the entire life cycle of Brazilian beef production, and found that those from transporting meat all the way to Europe made up just 2.5 per cent of the total. That suggests the added emissions from transporting more greens would be negligible compared with livestock emissions, says Pierrehumbert. There may be economic benefits to people shifting towards plant-based diets, too. Those who eat a lot of meat have higher rates of coronary heart disease, stroke, type 2 diabetes and cancer. Marco Springmann at the University of Oxford has looked at the costs of these illnesses. He estimates that if the entire world went vegetarian, we could avoid 7.3 million early deaths each year – 8.1 million if everyone were vegan. The healthcare savings would be worth more than $1 billion each year. “The biggest amount of [agricultural] subsidies go into livestock,” says Springmann. “We could take those and redirect them to meet more environmental and health goals.” All of this has helped me make up my mind. By the time you are reading this, I will have eaten all the non-vegan food I have left at home, and will once more be following a vegan diet. I will have to be more disciplined about getting enough of the nutrients I need this time around, and have started planning some standard meals to do that. I’m hoping it

will be a bit simpler than my last foray. As celebs promote vegan lifestyles and supermarkets start to cater for the trend, sourcing ingredients and planning meals gets easier. And I know already that the food won’t be all drudgery, despite common perceptions. For the years I was vegan, I celebrated Thanksgiving – a traditionally turkey-centric meal – with other non-meat eaters. It has always been my favourite holiday and I was worried at first that a vegan version would be lacklustre. I was wrong. Every year, we gave our annual thanks around a table full of Brussels sprouts and vegan “cheddar” biscuits, fake sausage stuffing and mushroom gravy. Tempeh or seitan or some other meat substitute usually made it onto the table, too. For dessert, we had pumpkin cheesecake made with cashews. It was bountiful and delicious and not lacking in anything, least of all joy. Q Chelsea Whyte is New Scientist’s physics news editor For links to studies referred to in this article, see the online version at www.newscientist.com 27 January 2018 | NewScientist | 31

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Research & Development | Real-World Value & Outcomes

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Commercialization | Technologies

KIERAN DODDS/PANOS

34 | NewScientist | 27 January 2018

PERIL ON THE SEA The shipping industry is in troubled waters, with sinkings still surprisingly common, says Joshua Howgego

LOST AT SEA

The statistics for 2016 reveal a variety of reasons why ships sink Sunk, submerged 46 Wrecked, stranded 15 Fire, explosion 8 Machinery damage 8 Hull damage 4 Missing 2 Collision with vessel 1 Miscellaneous 1

SOURCE: ALLIANZ (2016)

T

HE Stellar Daisy wasn’t quite halfway across the southern Atlantic when her crew heard a loud bang and the ship suddenly began listing badly. Jose Cabrahan grabbed a life jacket and an immersion suit designed to keep him alive in cold water and headed from the deck to the bridge. There he found the third officer sending a mayday transmission. Before he could do anything else, water began to pour in and Cabrahan jumped into the ocean. By the time he resurfaced, alone, the ship had disappeared. He found a life raft and eventually another member of the crew, and after 24 hours they were picked up by a ship. Despite a wide-ranging search, the other 22 men on board weren’t found. The Stellar Daisy had been carrying 260,000 tonnes of iron ore from Brazil to China. At 320 metres long, it was classified as a very large ore carrier (VLOC), the largest type of ship that transports metal ore. Ships like this aren’t supposed to sink – certainly not in reasonably calm seas like the ones the Stellar Daisy was traversing on 31 March 2017. At the moment, there is no certainty, just tantalising clues, as to what did for the Stellar Daisy. But posing the question takes us to the heart of one of the planet’s most important industries – one that, it turns out, is in the middle of the roughest squall it has seen in decades. If you leave out passenger ships and tugboats, there are about 51,000 commercial ships on the ocean, mostly cargo vessels transporting everything from fish fingers and fridges to cars and crude oil. We all depend on this industry. According to the United Nations Conference on Trade and Development (UNCTAD), about 80 per cent of the goods we trade go by sea.

This dominance is because ships move goods around cheaply, if slowly. Ships also emit less carbon dioxide than other modes of transport (see“Clean waters”, page 39). But shipping isn’t without its dangers. Huge storms, mutinies, pirates and collisions can endanger ships, and those episodes end in disaster more often than you might think. Just a few weeks ago, the Sanchi oil tanker collided with another ship 300 kilometres off Shanghai and burst into flames, spilling toxic oil condensate into the water. The ship is now reported to have sunk, with the loss of all its 32-strong crew. An average of 119 ships have been lost on the high seas each year over the past decade for a variety of reasons, according to insurance firm Allianz (see “Lost at sea”, above). > 27 January 2018 | NewScientist | 35

SEA CHANGE

Over the past decades, ever more and bigger ships have entered the oceans, powering global trade. We have gone to great lengths to accommodate them... 4

4 North-West Passage North-East Passage Transpolar sea route

1

3

2

DAY ON THE SEA This map shows the approximate position of 32,000 commercial vessels on 31 March 2017 — the day the Stellar Daisy sank (see main story)

Last known position of Stellar Daisy

Bulk carrier Container ship Gas tanker General cargo ship

Oil and chemical tanker Other tanker Roll-on roll-of cargo ship Specialised cargo ship SOURCE: SHIP POSITIONS DATA: MARITRACE AND ORBCOMM

TRAFFIC

SHIP SIZES

CHOKE POINTS

The amount of goods shipped worldwide has increased almost fourfold in 45 years

To meet demand, the number and size of freight ships have increased

The ocean’s busiest routes have had to expand to cope with increasing freight traffic and the size of ships

Panamax container ships (1980-) 250m long, 32m wide

1 Suez Canal

3 Nicaragua Canal

2 Panama Canal

4 Arctic routes

1970

2605 10,047

Post Panamax plus (2000-) 300m long, 43m wide

million tonnes 2015

million tonnes

Stellar Daisy. Very large ore carrier (built 1993) 322m long, 58m wide

Triple E class container ship (2013-) 399m long, 59m wide

36 | NewScientist | 27 January 2018

Opened in 1869, the Suez Canal is narrow and shallow, so only about 50 ships could pass through it each day. In 2015, Egypt launched the New Suez Canal project, a bypass lane to run alongside one section. This will roughly double the number of ships that can traverse the canal daily. It should also shorten the transit time from 18 to 11 hours.

This 77-kilometre-long waterway needs three locks at each end to raise ships the 26 metres between sea level and the canal’s main elevation. However, the original locks were too small for the biggest freight ships. So a new lane with much larger locks opened to traffic in 2016.

Chinese businessman Wang Jing has proposed a competitor to the Panama Canal. Its route through Nicaragua would be three times as long but it could accommodate the biggest ships. It would also slice through environmentally sensitive Lake Nicaragua and the lands of indigenous people. Little building work has started.

Soon other routes might open up. At the moment, the North-West Passage is often blocked with ice, with the North-East Passage a little less so. But within a few decades, climate change is expected to melt enough ice to open up even the Transpolar Sea Route, which runs through the middle of the Arctic.

...but now the industry is in fux, with its huge expansion butting up against lower demand

The Stellar Daisy went down in deep waters where traffic is sparse and pirates are almost unheard of. The Elpida, the first responder, was so far away that it didn’t arrive at the scene for 24 hours. The Stellar Daisy also sank extraordinarily quickly. As the ship began tilting, the captain called all crew to the bridge, but Renato Daymiel, the other survivor, told reporters that he never made it there. Instead, he found himself underwater “rolling like I was in a washing machine”. A strong gush pushed him out into the ocean where he fortunately found a floating life raft with Cabrahan inside.

FINANCIAL SQUEEZE A large increase in seaborne trade in the early 2000s encouraged ship owners to order more ships. But when the 2008 financial crisis hit, demand for shipping dropped as capacity soared, causing profits to plummet

80 60 40 SOURCE: UNCTAD

Daily earnings of Panamax-class bulk carrier ships (thousand $)

100

20 0 2007

2009

2011

2013

2015

$376m

Jupiter descending

Loss incurred by Maersk Line, the world’s largest shipping firm, in 2016

2017

FUTURE PROSPECTS There is some hope of a turnaround. Shipping firms have arranged themselves into three alliances to decrease competition…

Ocean Alliance 26%

The Alliance 16% K Line NYK Line

OOCL

MSC

Maersk

Evergreen

Hapag-Lloyd

CMA CGM

China Cosco

MOL UASC

Yang Ming Marine

*approximate percentage of world’s shipping capacity in January 2017

… and the creation of a massive network of roads and railways by China called the One Belt, One Road initiative could boost the amount of freight reaching ports in South Asia and increase demand for shipping

Hamburg Antwerp Prague

Brest Bryansk Belgrade

Sol-Iletsk Alataw pass Urumqi Xi’an Chongqing

Lianyungang Shanghai

New Eurasian land bridge railway Proposed road links

SOURCE: SCMP

Potential new shipping routes

SOURCE: F NANCIAL T MES

2M 32%*

So what happened? Investigations of shipping accidents are commercially sensitive, so information isn’t usually released until one has been concluded. The investigation into the Stellar Daisy’s sinking is being conducted by the Republic of the Marshall Islands, where the ship was flagged. International Registries, which acts as an administrator for the Marshall Islands, told New Scientist that the investigation was its “top priority”. Investigators are currently “conducting an in-depth marine safety investigation”, says a spokesperson, and the Marshall Islands is committed to “the sharing of lessons learned” to improve safety and prevent pollution. Yet it is possible to get an idea of what might have happened by looking at similar incidents. The Stellar Daisy is hardly the only large ore-carrying ship to have sunk in recent years. Between 2007 and 2017, 98 were lost. That includes four in one 36-day period leading up to Christmas 2010. An interesting case was that of the Bulk Jupiter, which sank on 2 January 2015 about 300 kilometres south-west of Vietnam, with the loss of all but one of the crew. It was carrying 46,000 tonnes of bauxite, an aluminium ore. And an investigation by the Bahamas Maritime Authority, where the ship was registered, strongly implicated the cargo in the sinking. We have known since at least the 1970s that several types of metal ore can be problematic. Even when they appear dry, they can contain a lot of moisture in the gaps between particles. Now the technology used to process ores has improved, it is possible to process lower-quality ores containing more impurities such as dirt and water. That in turns means more such ores are shipped. As a cargo ship makes its way across the ocean, the buffeting of the waves causes vibrations that can gradually coax any water from the > 27 January 2018 | NewScientist | 37

GHOST SHIP

The master of the Svitzer Hermod berthed his vessel alongside a quay in Copenhagen. Then he undocked, turned 360 degrees, and piloted a few kilometres along the water, before turning around and docking where he started. A rather pointless series of manoeuvres you might think – except that he wasn’t aboard the ship. This demonstration in 2017 was of the world’s first remotely operated ship, a joint project between Rolls-Royce and Svitzer, a firm that operates tugs. Remote-controlled and fully autonomous ships are the talk of the industry, partly because reducing the number of crew is one way to avoid loss of life during accidents (see main story). It might also avert those accidents, because 75 per cent are caused by human error, according to insurance firm Allianz. Rolls-Royce thinks remote-control ships will plough the oceans by 2030 and autonomous ones by 2035. The first autonomous ships will probably operate in local waters. For example, chemical firm Yara has announced that it will build an electric ship to carry cargo autonomously between two ports about 50 kilometres apart in southern Norway by 2020.

ROLLS-ROYCE

One way to reduce crew losses is to get rid of the crew

Ships like the Svitzer Hermod (above right) will be steered remotely (above) But Rolls-Royce is aiming for the open ocean. Funded to the tune of €6.6 million by the Finnish government, its Advanced Autonomous Waterborne Applications Initiative is developing a range of sensors for ships, better communication links with land, and algorithms that can interpret information from the sensors and

ore, a process known as liquefaction. It is an issue for bauxite and iron ore, among other dry cargoes. If a powerful wave then unbalances the ship, tonnes of water can slosh to one side of the hold and capsize the vessel in minutes. In the case of the Bulk Jupiter, a declaration compiled by the firm exporting the bauxite, Oxy Pte Ltd, stated that it had a moisture content of below 10 per cent. That is within international safety guidelines. But the departure of the ship was then delayed because of heavy rain. Some 370 millimetres fell over six days before the cargo was loaded, and the ore was exposed to the elements. During that interval, an intermediary called SGS Mineral Services tested the ore and reported an average moisture content of about 21 per cent. That led the investigators to conclude that liquefaction or a similar effect was the most probable cause of the sinking of the Bulk Jupiter. 38 | NewScientist | 27 January 2018

combine them with rules and regulations of the sea. This would allow the ship to react in the expected way if it is on a collision course, for example. Although uncrewed ships might make shipping safer in some ways, they may introduce fresh problems. Take cybersecurity, which is already a thorn in the side of the shipping industry. In April 2016, some 70 vessels that had departed Seoul harbour returned to the port citing problems with their GPS systems; South Korea said it had detected

Confirming that for certain is tricky, but computer modelling of a ship and its contents can help in principle, says Richard North at the UK Marine Accident Investigation Branch. Armed with details of the ship and sea conditions, modelling can, for example, show the amount of water that would have had to be

“The fatal accident rate for crews is 20 times that of the average British worker” present in the hold for it to capsize the vessel. At any rate, in the aftermath of the Bulk Jupiter incident, the UN International Maritime Organization, which has overall responsibility for rules and regulations on the high seas, sent a circular to ship masters warning them of the risks of bauxite

jamming signals sent from North Korea. If this were to happen to an uncrewed ship, it would be left highly vulnerable. Some countries, including South Korea and the US, are considering installing a backup system called eLORAN, or enhanced long range navigation system. This involves a global network of radio posts broadcasting signals that ships can use to triangulate their position. These signals can be about a million times stronger than GPS, so would be much harder to spoof.

liquefaction in addition to the known risk with other ores. Then in 2017, it alerted seafarers to research suggesting that a similar phenomenon called “dynamic separation” could also release large quantities of a water-ore slurry from bauxite. Liquefaction isn’t the only danger to large ore-carrying ships like the Stellar Daisy – there are also hints of structural problems. Some such ships weren’t originally built to carry metal ores. As the 2000s wore on, a huge demand for metal ore developed in China and some shipping lines began to convert crude oil tankers into solid ore carriers. These conversions, which are legitimate practice, proved an attractive option for many firms. Records from VesselsValue, a maritime intelligence service, show that of the 162 very large ore carriers on the ocean, 49 were converted from tankers. Among them is the Stellar Daisy. Its owner, Polaris Shipping, decided in 2007 to begin converting the then 14-year-old oil tanker into an ore carrier.

CLEAN WATERS

Ships emit relatively little carbon dioxide per tonne of goods transported 1 kilometre Air

560g 47g 18g 3g Road

Rail

Sea

Maersk Triple-E class ship

SOURCE: MOLLER MAERSK

That entailed an engineering overhaul that changed the ship’s structure. Liquid oil can be pumped into tankers through narrow inlets, but loading ore requires large hatches to be cut into the deck. Plus, the main supporting steelwork in tankers runs front to back, but in ore carriers it must run side to side. The conversion of the Stellar Daisy therefore involved a lot of new welding. About a week after the ship sank, a 15-centimetre crack was found in the hull of another vessel owned by Polaris, the Stellar Unicorn. Shortly afterwards, it was decommissioned. Then the master of the Stellar Queen, another Polaris vessel, found cracking on its deck and had to stop for repairs. Both ships were ore carriers that had been converted from tankers. Add to this Cabrahan’s report of a bang before the Stellar Daisy went down, and another explanation for the accident begins to look plausible: could the ship have split along a re-engineered join? “I don’t think any sentient being thinks the Stellar Daisy capsized for any other reason than a structural failure,” one master mariner told New Scientist. But the Stellar Daisy was inspected by the port authority in Tianjin, China, about two months before it sank. Two problems with watertight doors were identified, but no faults with the hull. Polaris did not respond to New Scientist’s requests for comment, but in an April 2017 statement it said it was “fully committed to ensuring the safety of its VLOC converted fleet and their crews”. It also announced a systematic structural survey of its fleet. It is not just Polaris that has been facing difficult waters. The shipping industry has been feeling the pinch for years. The mid-2000s were boom years, when demand for shipping and the cost of transporting all manner of goods by sea reached historic highs. Shipping firms put in orders for many new ships. But just as those ships began to arrive, the financial crisis of 2008 hit and demand plummeted, sending firms’ profits sinking. In 2016, a large firm called Hanjin Shipping went bankrupt, the first cargo shipping line to do so since 1986. In the same year, Maersk Line, the world’s largest shipping firm, made a loss of $376 million. It has since moved back into the black and

YANN ARTHUS-BERTRAND/GETTY

Seas the day: ships carry 80 per cent of the goods we trade

there are signs that the industry might bounce back too (see “Sea change”, pages 36 and 37]). For one thing, 12 of the biggest shipping firms recently changed the way they cooperate, forming three giant alliances. Each alliance has an agreement to carry other members’

cargo, meaning firms can avoid the cost of dispatching ships across the globe only partly full. Then there is the massive network of roads and railways that China is planning to build. According to UNCTAD, the One Belt, One Road initiative may bring more cargo to ports in South Asia, increasing the demand for shipping. Even if shipping does navigate its way into more profitable waters, other issues will remain. Take the long-standing controversy over so-called flags of convenience. Shipping firms often register or flag their vessels in nations other than the one in which they are based. According to trade unions such as Nautilus International, these flag states may have lower regulation and inspection standards, which enables the firms to operate at a lower cost. As of March 2017, the Marshall Islands – where the Stellar Daisy was flagged – is the second largest ship registry, after Panama. There is little sign of this trend abating. Yet we all depend on the goods that ships carry and so we share a stake in what happens on the high seas. “Our global shipping industry has a fatal accident rate 20 times that of the average British worker,” said Grahaeme Henderson, president of the trade association UK Chamber of Shipping, in 2017. “That is simply not good enough.” ■ Joshua Howgego is a feature editor at New Scientist. Additional reporting by Sandra Speares, a shipping journalist based in Godalming, UK 27 January 2018 | NewScientist | 39

INTERVIEW

Fossil fishing in the Yemen When a country becomes unstable or hostile, international scientists tend to withdraw. Not so palaeoanthropologist Ella Al-Shamahi

E

LLA AL-SHAMAHI digs in disputed or unstable territories by choice. That means her quest to explore the origins of humanity occasionally involves dodging landmines or considering how best to explain to airport security that carrying a laser scanner does not make her a terrorist. If the day job is stressful, could her alter ego as a stand-up comedian provide light relief? With Yemeni and Syrian ancestry, Al-Shamahi introduces herself on stage as a “one-woman axis of evil”. Though her work takes her to many troubled places, war-torn Yemen is her obsession. You deliberately work in politically unstable territories. Why?

It’s because these are places that science has forgotten. Often, they’ve forgotten science too, or the people living there simply have more pressing concerns. Yemen is virtually virgin territory, scientifically speaking. It just hasn’t been explored in the way that other parts of the planet have. What draws you to Yemen specifically?

The thing about Yemen is its deep civilisation. The capital, Sana’a, is a contender for being the oldest continuously inhabited city on earth and is a UNESCO World Heritage Site. I’m from Birmingham, UK, which has beautiful people, but isn’t the most beautiful city. I drop down in Yemen and I’m, like, oh God. Because it’s astoundingly beautiful. How is the situation in Yemen for your family?

I have cousins there, and some went into hiding because they were political and human 40 | NewScientist | 27 January 2018

rights activists. But their Facebook and Twitter updates were full of ridiculous, funny stuff. My uncle’s house was getting raided and I’d be freaking out, while my cousins were laughing about leaving strange things out for the rebels, just to confuse them. Humour in these circumstances is clearly a coping strategy, but it’s also a way of choosing to view the world. In terms of the humanitarian situation, it’s absolutely dire. A quarter of my extended family have left the country – they’re refugees. I get messages from cousins who are still there. They work in the public sector and haven’t been paid in many months. So even when food gets through the blockades they can’t afford it.

PROFILE Ella Al-Shamahi is a palaeoanthropologist and archaeologist at University College London specialising in Neanderthal evolution. She will also present the BBC2 TV series Neanderthals: Meet your ancestors in February

For work, why not just stick to safe places?

Because I think Yemen could be a key part of the story of human evolution and migration. The thing is, we have never found a human fossil anywhere on the Arabian peninsula. Not one. Loads of stone tools, but no Homo species, except for very recent Homo sapiens. That’s partly because the area has barely seen any palaeoanthropological work. Look at Kenya. It’s no accident that so many fossils have come out of East Africa. It’s because the Leakey family was based there. With Yemen, instability and war is in the way, but the rest of Arabia has another problem. There is a lot of desert, and it’s hard to preserve bone in desert.

mountainous, it was – and still is – massively green and it’s full of caves, which are perfect for preserving bones. It’s an area steeped in human history – who knows how far back that goes? And crucially, it is on a potential migration route out of Africa.

And you genuinely think Yemen is key for human evolution and migration?

You think early hominins could have left Africa by crossing the Red Sea to Yemen?

Yes, and it’s not because my family comes from there. There are certain clues that you go by; it’s a detective thing. Firstly, Yemen is

The route north across the Sinai of Egypt is considered to be the major one. But back then you could have seen Yemen from Africa – and

Sorry, did you say kidnappings were pleasant?

I know that sounds ridiculous, but I’ve met so many people with the loveliest kidnap stories in Yemen. Back then, it wasn’t Islamic militants, but local tribes. They’d host you like an Arab would host you, give you great food and say: “I’m sorry, you can’t leave because we’re just waiting for some money from the government.” That was common for geologists, who were often wandering in the middle of nowhere on behalf of the oil industry. But right now, no one’s going there?

There is a broader race right now to find the first major human fossils in Arabia, but the war in Yemen has thrown me out of the race. When it ends, my team is good to go. And we might find more than one species. There are lots of different kinds of stone tools, which could mean loads of different populations. Homo erectus was the first hominin to leave Africa. They went all the way to China, why

“There is a race right now to find the first major human fossils in Arabia” wouldn’t they have gone south to Yemen, too? We know Neanderthals were in the north of the Middle East – did they ever venture south? There’s so much potential in this area. And before the war, had you found any promising sites?

We have identified a cave that meets all the criteria for hominin habitation. The conditions are just perfect: there are water systems nearby as well as stone tools. I’m just desperate to get back there to dig it.

PETER DENCH

Is working in hostile or unstable locations good for comedy purposes?

you know what humans are like, once we see something… I think if you’re going to find fossils anywhere in Arabia, Yemen is the place to look. Why haven’t local scientists found fossils, assuming they are there to be found?

Palaeoanthropology isn’t really a thing there – even the nomenclature doesn’t really exist – and evolution isn’t taught. If you are interested in deep time, you become an archaeologist or a petrol geologist, and make money.

What about Western palaeoanthropologists. Has anyone worked in Yemen?

There have been a few teams that have looked at the area, but Yemen has been unstable for a while. If it suddenly became perfectly safe, as opposed to the kind of safety I’m willing to risk, there would be big teams wanting to move in. But Yemen has been an area prone to kidnappings for quite a long time, so that’s put a lot of people off. Mind you, as late as the 1990s, the kidnapping could be quite pleasant.

There have been times where things have got so dark I didn’t want to get on stage. Days before I was scheduled to fly in for my 2015 Yemen expedition, the war broke out. All our plans were up in smoke, everything was a mess. Lots of my family were still there, and God knows what was happening to them. I got on stage thinking, I don’t want to make you laugh. I want you crying with me. That said, comedy is really useful for people who do hostile stuff. It keeps us sane. And I’ve found that the people I meet in such places often have very funny, and quite dark, senses of humour. ■ Interview by Sean O’Neill 27 January 2018 | NewScientist | 41

CULTURE

When gene tech hides in plain sight Genomic innovations are appearing so quickly, we are struggling to identify, understand and regulate them, finds Lydia Nicholas

DICK DURRANCE II/NATIONAL GEOGRAPHIC/GETTY

IN THE 18 years since the Human Genome Project was declared complete, untold billions have been poured into projects promising to map and interpret our genetic code. Hopes and fears for the expected revolution have diffused through hospital waiting rooms, science fictions and pop-up adverts for off-the-shelf DNA testing kits. The promises come thick and fast. Surely we will soon see a

42 | NewScientist | 27 January 2018

revolution in healthcare, our futures laid out before us: diseases, abilities, lifespans, drug susceptibilities. Soon everyone will understand themselves in new, meaningful ways. There are risks, yes, though these also remain uncertain. Anyone for cloning? The planting of false genetic evidence? New forms of surveillance and discrimination? The world would certainly change – except that it hasn’t. Jenny Reardon’s The Postgenomic Condition draws on decades of fieldwork to tell stories that lay bare the intricate tangle of technologies, individuals, institutions, expectations, experiments, businesses, communities, acts of resistance and superhuman

efforts of grinding hard work that make up our genomic age. It is an example of the best kind of sociological writing, where specific, detailed, well-told stories are built into a powerful set of arguments with implications not only for the field in question, but for wider society too. This is a book not just about what went wrong in genomics, and how hopes for a better world go awry, it is also about what happens when our democracy encounters new technologies that refuse to sit still long enough to be understood. It is an enormous, messy would spill secrets of our past and challenge to take on. Fictional future: our pedigree (Kennel Club dystopias struggle to keep pace or otherwise), our susceptibilities with genetics. In a recent episode to illness, our innate capabilities of science fiction TV series Black and the traits and possibilities Mirror, an awkward nerd steals his we might pass on to our children. co-workers’ DNA to exploit and But recent years have seen a bully their clones. In the real, growing sense that this metaphor present world, white supremacists has failed. In 2010, Craig Venter, take genetic ancestry tests and the photo-finish loser of the race concoct conspiracy theories to “Anyone for cloning? The explain why their results don’t planting of false evidence? reflect the “pure blood” they New forms of surveillance crave. Once you have exhausted and discrimination?” your interest in your own DNA, you can post a stool sample to uBiome to sequence the bacteria to sequence the human genome in your gut, or send in your dog’s in 2000, said “we have learned spit to ascertain its breed. nothing” from the genome. And These tests draw on the since then, though sequencing persistent, enticing metaphor technologies have become faster of genetics as a “book of life” – and cheaper, and our biobanks a magical tome that, decrypted, and databases continue to grow, few clear single-gene causes for Bio-capital, Alabama-style: single, clear health problems have Residents of Tuskegee been identified. We are mired in T.J. KIRKPATRICK/THE NEW YORK TIMES/REDUX/EYEVINE

The Postgenomic Condition: Ethics, justice, and knowledge after the genome by Jenny Reardon, University of Chicago Press

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

Unfulfilled genetic promise: We are mired in an era of disappointment

disappointment; in Reardon’s words “struggling to reap the promised harvest of ‘meaningful knowledge’ that might foster life and human understanding”. We have a few genetic tests – for rare diseases such as Huntington’s and cancer risks such as the gene BRCA1 – but tests don’t mean treatments. They have value, but they aren’t the world-changing revolutions we thought we were trading our blood and tissues for. Billions and billions of dollars have been spent in a world short of doctors, where nurses visit food banks, where antimicrobial resistance is on the rise, where simple things that we know work to radically improve population health (education, empowerment, better food and housing) are inaccessible to so many. Was chasing the slim hope of staggeringly expensive, targeted treatments for the elite really the

best use of our resources? Reardon faces these questions head on. Visiting a largely black rural community in Tuskegee, Alabama, she speaks to local people who have been asked for DNA samples. Living in the shadow of the infamous Tuskegee syphilis study, which ran roughshod over the interests of black male patients in the pursuit of medical data, they are understandably suspicious. Their entrenched poverty has made them valuable research subjects: unable to escape, many families haven’t moved far since their ancestors were emancipated. There is no hospital within a 40-minute drive, and a genetic test to see if a child has sickle cell anemia, for instance, is a pointless luxury as the family couldn’t afford or access care either way. “The truth as I see it: [genetics] is not important,” says one resident,

Geoffrey Nunberg, “there’s no road back from bits to meaning”. We learn that Iceland, home of the Althing, the world’s oldest extant parliament, was, appropriately, the first place to define its population’s genetic matter as a lucrative natural resource. Developing a strategy to exploit it proved far harder. An international scandal followed and the project stagnated. Another national genomic project, Generation Scotland,

“And it’s not important because there is so much else wrong.” There is no simple enemy here, and no single mistake. In her account of the Human Genome Project, Reardon refuses to succumb to the familiar myth in which valiant academics worked through the night to vanquish greedy corporate interests and save the genome for the human race. She paints “Genetic tests have instead a nuanced picture of the value, but they aren’t the actions and motivations of the revolutions we thought we institutions and individuals were trading our blood for” involved. This refusal to settle for simple answers is maintained attempted to improve on Iceland’s throughout the book. efforts. Focus groups, interviews The theoretical argument and surveys were employed strung through this chain of to ensure that the project’s stories – about national biobanks “benefits” would be returned to and start-ups, research projects and acts of community resistance, the National Health Service and the public. Reardon leads us along experiments, ad campaigns and the path by which these benefits, corporate takeovers – centres on as the public understood them – Hannah Arendt’s assertion that respect for the communal nature democracy relies on our ability of the information contained in to identify things of value, and DNA; promotion of health as a to gather around those things common good – mutated into to decide what to do with them. In genomics (and, by implication, a simple, four-way split of the profits. And then how it became the wider world of frantic technological innovation), Reardon clear, despite the best intentions, argues that every part of this that there would be no profit, construction comes under threat. and probably little knowledge. The main outcome of the project was an improvement in the A blur of innovation design of corporate-owned The current pace of technological sequencing machines. change and rapidly developing The challenge in these tales is scientific understanding means to stop looking for evil, singular, that “things” are developed and pantomime villains (there are discarded so fast that we are none, though the book features unable to identify them and spectacular characters and then debate or regulate them. tense conflicts), to look past the “Thinking”, too, is degraded by markets and their inability to being offloaded to machines provide meaningful answers that can compute but never to the challenges set by new understand. Reardon draws technologies, and deal with on philosopher Jean-François the fact that our democratic Lyotard’s claim that automation institutions, faced with these reduces thought to data handling same technologies, aren’t even so that “knowledge is unhinged framing sensible questions. ■ from its claim to truth and to Lydia Nicholas is a researcher in justice”. We have all this data, data and culture but in the words of the linguist 27 January 2018 | NewScientist | 43

CULTURE

Backdoor to the future In a highly networked, increasingly insecure cyberworld, smartphones make us powerful and powerless as never before, finds Nina Jankowicz

AS OF 2017, 72 per cent of people in the UK have smartphones. What this means for society depends on more than the strength of their mobile signal and battery life – it depends on governments and whether they demand exceptional access to devices. In her book Listening In, Susan Landau, a cybersecurity expert and academic, argues that in an increasingly insecure cyberworld, “society is best served by securing communications and devices even if that… makes government investigations more difficult”. The impasse between the FBI and Apple over a locked iPhone containing potential evidence about the 2015 San Bernadino shootings is Landau’s narrative thread, as she weaves a sometimes circuitous path through the digital revolution to the networked world and its implications for national security. The first two chapters in particular read like a textbook on the internet for future students. But her ultimate prognosis for a world in which governments are granted “backdoors” to individual devices is bleak. Forcing Apple et al. to develop a universal solution to unlock suspects’ phones creates a mechanism that could easily be hijacked by a country like Russia. Indeed, the Kremlin targeted Smartphones connect the world, but what will that mean for society? 44 | NewScientist | 27 January 2018

“civil society’s soft underbelly” time in modern history have in the 2016 US elections, asserts individuals had more power to Landau, adding that the only shape conflict than the present. solution is to make both In War in 140 Characters, communication mode and device journalist David Patrikarakos secure. Rather than pursuing a uses engaging case studies from universal key, law enforcement the Israel-Palestine war, the should invest in more hackers. Russia-Ukraine conflict and the While better cybersecurity can rise of ISIS to explain a new plane protect data and systems, it won’t of warfare. This can empower win the war of words Russia and individuals to do good, as when others are fighting. But if Landau’s a volunteer in Ukraine used account makes readers worry that “Better cybersecurity can they are powerless in the face of protect, but it won’t win their state, let alone other states the war of words Russia seeking to weaponise their data, and others are fighting” they can rest assured that at no

FERHAT BOUDA / AGENCE VU/CAMERAPRESS

Listening In: Cybersecurity in an insecure age by Susan Landau,Yale University Press War In 140 Characters: How social media Is reshaping conflict in the twenty-first century by David Patrikarakos, Basic Books

social media to organise donations of gear, clothing and gifts for poorly equipped soldiers. Patrikarakos writes “as the state fails, Homo digitalis rises to take its place”. But the state can also seize these powers for ill. Patrikarakos profiles a member of Russia’s infamous troll factory, where hundreds of employees post fake comments and news stories to sway public opinion in favour of Russia, and gives a case study of the emotional connections forged between a disaffected French citizen and her ISIS recruiters. These show the impact of a savvy state (or pseudo-state) that understands social media. States that do not, including, according to Patrikarakos, the US and to a lesser extent Israel, cede control of an increasingly vital battleground: the internet. Like Landau, his prognosis is grim: “Our information environment is sick”; his antidote is an investment in journalism. Both authors focus on supplyside, field-specific solutions to the challenges: better security, better reporting. But both stop short of solving the demand-side. Even without hacked information, increasingly polarised societies fuel fake news and poor journalism – which are then weaponised by foreign powers or serve domestic aims. It is this polarisation, driven largely by the online information environment, that can affect society more than any single smartphone for decades to come. ■ Nina Jankowicz is a foreign affairs specialist based in Washington DC

INFINITY AND BEYOND Your ultimate guide to mathematics =HURLQĆQLW\ZRQGHUQXPEHUVSUREDELOLW\DQGVWDWLVWLFV V\PPHWU\DQGUHDOLW\FRPSXWDWLRQDOFRPSOH[LW\PDWKV DQG\RXUEUDLQDQGPXFKPRUH %X\\RXUFRS\IURPDOOJRRGPDJD]LQHUHWDLOHUVRUGLJLWDOO\ )LQGRXWPRUHDWnewscientist.com/thecollection

LETTERS

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EDITOR’S PICK

Could we be entering a new anaerobic age? environments, but they are not widespread and thus “no longer have a significant effect on Earth’s climate”. But anaerobic “dead zones” are proliferating in the oceans now and are probably increasing in size (9 December 2006, p 38). Does this mean that organisms of the sort described are due for a renaissance, thriving in this new human-made habitat? If so, has the effect of their methane production been factored into climate models?

From Ben Haller, Ithaca, New York, US

The editor writes:

Alice Klein reports evidence that early anoxygenic photosynthesis produced so much methane that it warmed the planet by about 15°C (16 December 2017, p 11). She also notes that anoxygenic organisms exist today, photosynthesising in anaerobic

Klein noted that anoxygenic photosynthetic organisms like green sulphur bacteria and purple bacteria cannot tolerate oxygen. But ocean dead zones tend to move around, so these organisms might only thrive if they evolved to be more tolerant.

Q

Many worlds are taken seriously… somewhere From Craig Gaston, Gatineau, Quebec, Canada You report Yasunori Nomura saying that the “many worlds” approach resolves the paradox around information loss from black holes and “should be taken seriously” (6 January, p 14). My self in another universe takes it seriously, but not in this one.

A balanced diet need not be expensive or futile From Rosemary Sharples, Penshurst, New South Wales, Australia Anthony Warner says that “when people restrict what they eat, keeping nutrition balanced and adequate can be harder” (6 January, p 24). Some say that this is difficult because fruit and vegetables are expensive. Snow

@newscientist

newscientist

peas and dragon fruit, for example, may well be costly, but ordinary fruit and vegetables are not. Recently, I asked the assistant at my local greengrocer to tally the bill again because I could not believe the low total she had rung up. The problem for most of us is that fruit and vegetables are not filling in the way that junk food can be. Repetition of “Mum, I’m hungry” is a quick way to wear down Mum’s resolve to feed her children only “healthy” food. What is needed is more expertise in making food that is filling and healthy; and ensuring this is not the province of family doctors. From Charles Parsons, College Park, Maryland, US Warner comments that “Calories in, calories out, or CiCo to its new devotees on social media, is all the rage. It just doesn’t add up…” Well,

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“But I don’t want to gain extra time if I have to spend it all doing housework…” Carolyn Jones is not thrilled by the suggestion that 150 minutes of housework a week can help extend life (13 January, p 26)

yes, it does, it may be the only sane way to diet, and it doesn’t deserve dismissal just because millennials are on board. Warner uses most of his space to explain that diets don’t work for a collection of reasons that have nothing to do with dieting. At least he pointed out that CiCo is sounder than the faddier nonsense of recent years.

Dancing to the thrum of the generators at 6am From Matt Black, Blockley, Gloucestershire, UK Combine your articles on psilocybin and other psychedelic drugs having beneficial effects on the brain (such as 25 November 2017, p 28) with the promising reports of 40 hertz bass tones and flickering lights reducing the tangles and plaques of tau and amyloid proteins that are

correlated with Alzheimer’s disease (6 January, p 6). Then add the benefits of sharing an enjoyable social get-together with dancing as exercise… Is it time to admit the ravers were right all along?

Raise a dram to effects of the grape depression From Roger Leitch, Bath, Somerset, UK Chris Simms traces some effects of the destruction of grapevines in 19th-century France by aphid-like phylloxera (23/30 December 2017, p 60). One other effect was a shortage of cognac. As a result, particularly in the gentlemen’s clubs in London, they drank malt whisky instead. Until then, Scotland produced more whisky than it could consume and much was sent off to be turned into gin. But whisky

became so popular after the phylloxera blight that distillers supplemented the malts with grain whisky, since these blends were cheaper to produce.

Why radiation and heat are a lethal combination From Luce Gilmore, Cambridge, UK I am not surprised tardigrades are killed by high temperatures with ionising radiation (6 January, p 19). It has been known since the 1960s, for example, that bacteria succumb to a combination of radiation and vacuum. An organism exposed to high temperature and vacuum can shut down and tough it out. But surviving radiation requires an active metabolism to turn out new proteins and repair DNA faster than those molecules are being degraded. This is bad news

for the idea of panspermia – that life spreads on comets and so on. Deep space is a cold vacuum and cosmic ray particles are abundant.

Has brand loyalty had its day for drugs? From Henry O’Regan, Harpenden, Hertfordshire, UK Alice Klein reports that doctors and patients alike are not keen to move to cheaper counterparts of biological drugs such as the breast cancer treatment trastuzumab, sold as Herceptin (6 January, p 23). This is despite studies finding that such generic biologics or “biosimilars” are just as effective. I suggest that the reason for this is a cultural prejudice against imitators of popular products. If a well-known company sells a pair of shoes for £150 and another company makes exactly the same shoe with the same materials >

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27 January 2018 | NewScientist | 53

LETTERS but without the logo, people are more likely to buy the branded make whatever the price. I think trust in well-known brands explains this, and the reluctance to accept generic drugs, more than the fact that biosimilars aren’t exact copies of biological drugs. Do we need to change this?

Killer waves form at cross purposes From Bruce Denness, Whitwell, Isle of Wight, UK You reported 40 years ago that huge “killer waves” were more likely to occur where the sea floor topography rises more steeply at the edge of a continental shelf (Old Scientist, 6 January). At about the same time, Chris Machen, then my colleague at Newcastle University, UK, demonstrated in a specially designed wave tank that another factor was also important: waves should be crossing and breaking. Contrary to the conventional theory of the day, breaking waves crossing others approximately at right angles can rise more than the sum of their heights, even TOM GAULD

[email protected]

inshore. Examples can be found in the choppy waters at harbour entrances next to reflecting sea walls, though these are much smaller than offshore killer waves.

Some place names are drier than others From Crispian Strachan, High Wycombe, Buckinghamshire, UK Richard Webb traced wet place names in the UK (23/30 December 2017, p 51). He might like to trace dry names as well. Clifton (“place on a hill”) is usually up a slope from a stream and St Michael’s Church is often on a hill because St Michael threw the Devil down from heaven. There are indeed many keys in place names.

If we fall down, help us to get up again From Joan Zealey, Balgownie, New South Wales, Australia Alice Klein’s account of training for older people to prevent falls was interesting (6 January, p 12). My mother had frequent falls in her last decades, and said: “I can fall safely, but once I am on the

floor, I can’t get up again.” She had to wait for her carer to arrive, or press her emergency button to be rescued. Can we also have some research to help those who fall properly to then get on their feet?

No one actually needs a gas guzzler, do they? From Alec Cawley, Penwood, Berkshire, UK Ernest Ager asks why cars with large engines should pay high vehicle tax as well as being taxed on higher fuel consumption (Letters, 23/30 December 2017). Such a car is a luxury, and we usually tax luxuries more. Until we overhaul our society significantly, some road transport will be needed. But a small car can provide our transport needs, with lower emissions. A vehicle pumping out more is a choice.

How long do civilisations last, out there? From Anthony Richardson, Ironbridge, Shropshire, UK Fergus Hawkins writes that “any extraterrestrials we

@newscientist

newscientist

encounter are as likely to live in caves as to be superintelligent” (Letters, 13 January). This appears to assume that any civilisations that have existed in the universe have a very limited timespan. For those two possibilities to be equally likely implies that a species takes a certain time to reach our stage of civilisation, then a similar time to destroy itself or otherwise fail. This idea has, of course, often been put forward to explain why we do not hear from civilisations with even 1000 years more development than we have had.

Schrödinger’s paradox is settled by actual cats From Bill Smith, Helsby, Cheshire, UK I have a solution to Schrödinger’s cat-in-a-box paradox, based on the following verifiable observations. When I wish to use my armchair, I find our cat asleep on it. When I wish to use my study, the cat is asleep on my chair. When I go to bed, the cat is sleeping on my bed. Therefore the answer to Schrödinger’s paradox is surely that the cat is not dead, but merely sleeping. Furthermore, it is not even in the box, it’s where it’s not supposed to be. I hope that settles the matter.

For the record Q Over-40s made up about a third of those at Andrew Kolodny’s addiction clinic (13 January, p 35). Q The dead animal illustrating the article on trophy hunting was a wildebeest (13 January, p 42).

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 | 27 January 2018

MAKE

RUSSELL COBB

Do try this at home

Cycle for your supper Maintain your good intentions for 2018 with a pedal-powered contraption that shreds veg for healthy meals “This year I made three resolutions: write to more magazines, eat better and exercise more,” says Paige Turner. “So far I’ve managed one, but as for the others, I’m already fed up of yoga and yogurt. Can you help?”

The new year is filled with promise: namely the promises we make and then break. We’re too busy to hit the gym or dice the contents of the fridge ready for the week ahead. If only we could do it all at once. Turns out, you can. Step one, healthy eating: get ready for courgetti (courgette spaghetti, or zoodles if you’re across the pond). The spiraliser is a musthave gadget to shred your veg into ribbons that replace carbheavy pasta or just make vegetables fun enough that you don’t hate eating them. Mine has a top handle you crank to twirl out vegetable streamers. Now, the exercise. The upper body workout of the spiraliser alone is not enough. I tried weighting it to make a spiraliser dumb-bell, and adding resistance to its shaft. These plans didn’t bust many calories other than food lost to spillage. Then inspiration struck. I blew

the dust off last year’s promise: an under-desk exerciser. I could cycle for my supper. An accident that left my kitchen covered in the wrong sort of oil proved it’s trickier than it sounds. I needed a way to transfer power from pedal to peeler, stepping down the difference in radius. A large cardboard disc proved too flimsy, an old LP too brittle, but balsa wood was just right. I zip tied a pedal to one side and the spiraliser handle to the other. After loading my dinner, I pedalled furiously, but the carrot only twirled in place. Lying on its side, without gravity to assist, my spiraliser couldn’t get purchase. A swift solution: a spring around the spiraliser crankshaft encouraged my veg towards the blades. Success! Next, I’ll add gears so I work harder for my meal. Perhaps they could change according to the calorie content of the shreddable edible. Does my device give a better workout than jogging to the shops for the pre-prepared stuff? Who’s to say, but running to the hardware store three times in a day must have helped. Hannah Joshua ■

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FEEDBACK

For more feedback, visit newscientist.com/feedback

MORE fortune telling: Steve Etzel finds tech reporter Timothy Lee discussing the yo-yoing value of bitcoin on NPR. “I think it’s going to continue to be volatile,” he told host Scott Simon . “I think it will probably go up more, but I don’t know how much more. And then I think it will probably crash. But I don’t know how much – you know, how far down it will decline.” So now you know.

PAUL MCDEVITT

ASTROLOGY is not bunkum, news site Quartz would like you to know – it’s simply been ruined by modern psychology. That is the startling conclusion of Ida C. Benedetto, who claims that the exact science of astral fortune telling as practised by the Ancient Greeks has been cast aside in preference for digestible feel-good aphorisms. In addition to Carl Jung and his ilk, Benedetto blames New Age hippies and turn-of-the-20th-century mystics for astrology’s debasement into pseudoscience. The deterministic powers of fashionable newcomers Neptune, Uranus and Pluto are given disproportionate emphasis in modern readings. And the familiar bestiary of star signs, we are told, is “a recent creation designed to appeal to mass audiences”. Perish the thought. Now that Ancient Greek texts on astrology have been translated, the unsullied form can be revived. This heralds a return to the rigorous practice of observing stars for hidden meaning, which Feedback had naively

thought lived on as astronomy. Like the best soothsaying, Benedetto never quite gets round to identifying just what makes this authentic astrology any better than the regular variety, nor what benefits we can expect to reap. Feedback feels comfortable making its own prediction: traditional astrology will prove every bit as insightful as its latter-day offspring.

STILL, no less than the big guns at the University of Oxford seem to be getting on board. Ian Witham picked up a “Classic Telescope” from its Young Scientist series of gifts for curious children. “On the back of this box, we are told that Oxford University is committed to science, our children can do their own experiments, and that Oxford graduate Roger Penrose identified the properties of black holes in 1969,” he says. But on the front, it encourages him to “have fun exploring the wonders of astrology”.

Alan Beasley’s local supermarket cafe has provided a microwave for warming baby food. A sign placed nearby warns customers: “Heated food can be hot” 56 | NewScientist | 27 January 2018

KODAK has seen better days since the advent of digital cameras destroyed the market for photographic film faster than you can say ISO 800. The firm filed for bankruptcy in 2012. But earlier this month, Kodak’s stock price tripled in less than a day after it announced the launch of its own bitcoin-style cryptocurrency, KodakCoin. This is by no means an isolated incident. Last month, US soft drinks retailer Long Island Iced Tea – surely more at home with beverages than blockchains – announced it was moving into cryptocurrencies, and watched its stock price jet up by 500 per cent. Bloomberg Technology recounted a series of similar pivots from firms that previously dealt in cigars, real estate, mobile games, e-cigarettes and sports bras, full circle back to the drinks industry with SkyPeople Fruit Juice, now trading as Future FinTech Group. Launching your own cryptocurrency? It’s a licence to print money. A NEWSLETTER delivered to John de Rivaz offers a digest of the latest trends on the London Stock Exchange, “Just Eat was the best performer at the open, up 2.1 per cent after Barclays raised the online takeaway platform to Overweight from Equal Weight.” Fans of home-delivered dinners will no doubt know the feeling.

“AUSSIE flu to kill 750,000 people,” the UK’s Daily Star declared earlier this month, adding there were “fears deadly epidemic will wipe out Brits”.

That last part is true, of sorts: it is based on the government’s recent disaster planning report, which singled out a pandemic flu as a substantial threat. The estimate of 750,000 deaths, however, is modelled on the catastrophic 1918 flu pandemic, not the current Aussie variant. Hold the vaccines, however, as a follow-up article identifies an unusual preventative measure. The newspaper reports that couples who enjoyed regular bouts of sex showed increased levels of infection-fighting immunoglobulin A in the blood, and were therefore more likely to ward off winter bugs. All the more reason to fear a shortage of hospital beds? GREEN energy provider Bulb offered customers a beastly start to the year with a breakdown of their reduced environmental impact.

“Together we could save the weight of a pride of 13 lions in CO2 a year,” Neil McKay is told, while Graham Knight discovered that he is saving “the weight of a giraffe in CO2 every year”. “I don’t think I’ve ever seen lions used as a unit of measurement before,” says Neil, “but taking pride in our efforts to reduce our carbon footprint can only be a good thing.”

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 Hair of the dog?

Lead astray

I’ve watched TV documentaries that show people’s pets receiving chemotherapy. It doesn’t seem to cause them to lose their fur or hair, unlike humans. Why?

How much lead was used in the manufacture of leaded petrol before it was banned, and where is that lead now?

Q Leaded petrol was phased Q Follicles go through cycles of out in most industrial nations growth, degeneration and rest, in the late 1990s, with the last and then regeneration and significant quantities being made another growth phase. During in 1997. In that year, 22,250,000 growth, the follicle cells divide to tonnes (about 30 billion litres) create the hair shaft. The natural of petrol were manufactured for length of this shaft is controlled use in the UK, of which 6,140,000 by the extent of this phase. To tonnes (8 billion litres) were conserve energy, in most animals, leaded using the “anti-knock” growth stops when the shaft engine-protection compound reaches an appropriate length, tetraethyl lead (TEL). the follicle degenerates, the hair “Being water soluble, lead shaft is held in the skin and the bromide results in lead follicle goes into its rest phase. ions getting into the Chemotherapy stops cells food chain very easily” from dividing and therefore doesn’t damage resting hair At that time, the maximum follicles, which is probably why permitted amount of lead was animals don’t usually lose hair. However, they might if treatment 0.15 grams per litre, equivalent to 0.23 grams of TEL. So, 1228 tonnes took place during their moulting cycle when new hairs are growing. of lead entered the environment via exhaust pipes – the lowest The human head is unusual amount for many years. Prior to in that hair growth cycles are 1984, the maximum lead level was asynchronous. At any time, only 0.4 grams per litre, so emissions about 10 per cent of follicles are would have been roughly 9000 resting, with the remainder in a tonnes a year, even taking into growing phase that continues for account the fact that not all grades up to seven years. This is why of fuel contained the maximum human head hair, unlike that of permitted amount of TEL. most other animals, can reach But the pollutant was neither more than a metre in length if left the metal nor the oxide, it was uncut, and why chemotherapy lead bromide. In the 1920s, various in humans affects these follicles, organometallics were tested in resulting in hair loss. petrol, including the very effective Paul Kemp ferrocene. The advantage of TEL Manchester, UK

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was that deposits of the metal or its oxide could be swept out of combustion chambers by adding a halide compound to the petrol, which converted them to lowmelting lead bromide. (Older drivers may remember the pale grey look of exhaust pipes. That was caused by this compound.) Being water soluble, it results in lead ions getting into the food chain very easily, and they build up in top predators, such as humans. But in countries with regular rainfall, lead bromide is fairly rapidly washed out of soil, lakes and inland waterways. So the answer to the question is: it is in the sea. The decline of lead in the UK population is supported by a 1998 report that stated lead levels in blood had fallen to onethird of typical results from 1987. TEL is still used today in small and diminishing quantities to make standard 100-octane aviation gasoline for older aircraft, but the vast majority of light-plane engines use normal 95-octane, which is lead free. John Rowland Allestree, Derby, UK

Human attraction How small would something need to be for the gravitational field of a human to significantly affect it? At what point would something be attracted to someone or able to establish an orbit? (Continued)

QThe time it would take a hydrogen atom to orbit a human

should have been 10 times longer than the 2.5 hours I claimed in my earlier answer, that is 25 hours (6 January). I clearly cannot read the display on my calculator. Mike Follows Sutton Coldfield, West Midlands, UK

This week’s questions LOAD OF RUBBISH

Rubbish collection seems complicated these days. Where I live, I use five different bins and the collections are fortnightly. Unlike many people I observe, I squash things like aluminium cans and plastic milk bottles. It seems logical and reduces the volume of rubbish stored in the house – but does doing so help collection and recycling? Patrick Forsyth Maldon, Essex, UK SIGN OF MATURITY

Last year, we had a Christmas pudding that was two years old and it was superb, whereas a one-year-old pudding wasn’t nearly as tasty. I read that a supermarket won an award for its two-year-matured puddings. So, what happens over two years to bring out the flavour? Peter Slessenger Reading, Berkshire, UK FLOWER UNDERPOWER

Why does a bee only visit one type of flower at a time? It seems such a waste of energy. Barbara Fisher, Cook, Australian Capital Territory