May 11 –17, 2019 New Scientist

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AI-powered drug discovery for rare diseases There are over 7,000 rare diseases. Only 5% have an approved treatment. Using traditional drug discovery methods, it will take a very long time to find treatments for all these diseases. Here at Healx, we are changing that.

Genomic map of rare diseases This is a genomic map of 3,039 rare diseases with genetic causes. The spiral graphic represents the human genome. It’s formed of 2,071 segments, each containing 1.5m DNA base pairs. The green dots show where the genetic mutations are located for each of these diseases. Inspired by the work of Martin Krzywinski ‘Genes that make us sick’. Number of diseases

healx.io |

[email protected]

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THE LIFE BELOW

Exploring the vast biosphere miles beneath your feet

AUTISM THERAPIES

The hormone drugs that could improve social skills

FASTER PRIMES

Ancient Greek math gets an upgrade WEEKLY May 11–17, 2019

MESSAGES FROM DEEP SPACE

Mystery radio signals keep hitting Earth. We’re finally cracking the code

CAN AI CREATE ART?

1 9

Marcus du Sautoy on artificial originality

PLUS IS IT REALLY SO HARD GOING GREEN? / NARWHALS THRIVING / HOW YOUR BRAIN CHANGES IN ORBIT / JURASSIC STOWAWAYS

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We’re looking for the best ideas in the world. The Ryman Prize is an international award aimed at encouraging the best and brightest thinkers in the world to focus on ways to improve the health of older people. The world’s ageing population means that in some parts of the globe – including much of the Western world – the population aged 75+ is set to almost triple in the next 30 years. The burden of chronic diseases including Alzheimers and diabetes is set to grow at the same time. In order to stimulate fresh efforts to tackle the problems of old age, we’re offering a $250,000 annual prize for the world’s best discovery, development, advance or achievement that enhances quality of life for older people.

The Ryman Prize was first awarded in 2015 to Gabi Hollows, co-founder of the Hollows Foundation, for her tireless work to restore sight for millions of older people in the developing world. World-leading researchers Professor Henry Brodaty and Professor Peter St George-Hyslop won the prize in 2016 and 2017 respectively for their pioneering work into Alzheimer’s Disease. The 2018 Ryman Prize went to inventor Professor Takanori Shibata for his 25 years of research into robotics and artificial intelligence. If you have a great idea or have achieved something remarkable like Gabi, Henry, Peter and Takanori, we’d love to hear from you. Entries for the 2019 Ryman Prize close on Friday, June 28, 2019.

Go to www.rymanprize.com for more information

Prime Minister Jacinda Ardern with 2018 Ryman Prize winner Professor Takanori Shibata.

www.rymanprize.com

This week’s issue

42 The life below Exploring the vast biosphere miles beneath your feet

On the cover

Coming next week

12 Autism therapies The hormone drugs that could improve social skills

34 Messages from deep space Mystery radio signals keep hitting Earth. We’re finally cracking the code

11 Faster primes Ancient Greek maths gets an upgrade

38 Can AI create art? Marcus du Sautoy on artificial originality

The new race for space Launching our coverage of the 50th anniversary of the Apollo moon landing, we ask who will be next to walk on the moon

10 Is it really so hard going green? 19 Narwhals thriving 8 How your brain changes in orbit 12 Jurassic stowaways Vol 242 No 3229 Cover image: Dániel Taylor

News

Features

10 Net zero The plan to slash the UK’s carbon emissions by 2050

34 Messages from deep space The mystery of fast radio bursts may finally be solved

News

38 Can AI create art? Finding out demands a deep dive into human consciousness, says Marcus du Sautoy

12 Autism therapies Hormones found to improve some symptoms 16 AI road monitoring Artificial intelligence to detect traffic accidents

42 The life below Microbes flourishing underground could reveal life’s strange origins

Views

The back pages

23 Comment When it is us vs the gadgets, we are the weakest link

51 Maker How to test the conducting properties of asparagus CHRIS & MONIQUE FALLOWS/NATUREPL.COM ABOVE: NASA/GETTY

24 The columnist James Wong dispels claims we have only 100 harvests left 26 Letters Why do we care what we are made of? 28 Aperture Ground squirrels in the Kalahari desert mob a curious cobra 30 Culture A voyage into a mythical dead world reveals truths about us

9 Sharks are smarter than they look

52 Puzzles Cryptic crossword, a quiz and a railway riddle 53 Feedback The week in weirdness: Marvel vs phobias, and ZooTube 54 Almost the last word Space junk and insect feelings 56 Me and my telescope Mars geologist Tanya Harrison answers our questions

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The leader

An emergency we can solve

GEORGE COPPOCK/GETTY

Urgent climate action is absolutely necessary – but with hope, not despair CLIMATE change is having a moment in the UK. In recent weeks, diverse voices have called for urgent action on greenhouse gas emissions. Partly in response, the UK parliament has become the first in the world to declare a “climate emergency”. While we should welcome the fact that the urgent need to decarbonise has finally broken through in the public consciousness, there is a danger in going too far. As teenage climate activist Greta Thunberg says, the house is on fire – but our response should be to calmly exit the building and execute a rescue plan, not to run about in a panic while the entire thing burns down. Such a plan comes in the form of a detailed report that the UK Committee on Climate Change revealed last week (see page 10). Yes, we do need to make

To reduce carbon emissions, the UK will have to use part of its farmland for planting trees

changes across the entirety of society, rethinking everything from boilers to buildings. But examine the detail, and you will find that we don’t need to live in mud huts to go green – technological developments and smart choices over the next two decades will allow us to be more eco-friendly without truly radical changes to our behaviour. Solving the climate emergency will also mean harnessing innovation in novel ways, such as repurposing oil rigs

to harvest cobalt from the oceans to make electric car batteries (see page 15). We should see this as an exciting opportunity, not an apocalypse. As the first nation to industrialise, the UK has a moral duty to decarbonise, but if that is too woolly a reason for you, think of the financial benefits of becoming a green technology leader. The future of modern economies is inescapably carbon-free, which is why China is now the leading producer of electric cars and solar panels. The only way the UK can compete is to leap ahead and start selling its products and services to the rest of the world. Activists should be applauded for putting climate change at the top of the agenda, but we must ensure that dire warnings don’t obscure a message of hope. We can do this. ❚

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Where did we come from? How did it all begin?

And where does belly-button fluff come from? Find the answers in our latest book. On sale now. Introduction by Professor Stephen Hawking

News Aviation

Technology

Cutting YouTube’s carbon footprint

XINHUA/REX/SHUTTERSTOCK

A SIMPLE tweak to YouTube could reduce its annual carbon footprint by the equivalent of that from 30,000 UK homes. When listening to music on YouTube, only people using the premium version of the app can opt for audio alone, meaning many have to unnecessarily load the video as well. Rolling this radio mode out for everyone would lower carbon emissions by the equivalent of 100,000 to 500,000 tonnes of CO2 per year, estimates a team at the University of Bristol, UK. The team presented its findings at the ACM CHI Conference on Human Factors in Computing Systems this week in Glasgow, UK. ❚ Donna Lu

Emergency landing

Environment

A lightning strike may have led to the deadly crash landing of a passenger plane in Moscow, reports Michael Le Page FORTY-ONE people died after an Aeroflot flight carrying 78 people caught fire on 5 May while making an emergency landing at Sheremetyevo airport in Moscow, Russia. Footage of the incident appears to show the undercarriage giving way after the plane bounced while landing. The Russian-made Sukhoi Superjet took off at 6 pm and attempted to land 28 minutes later. A lightning strike just minutes after take-off reportedly disabled its main radio and automatic control systems. The plane, which was headed for Murmansk, reportedly landed with full fuel tanks, which would have made it much heavier than during a normal landing. When planes have to land soon after take-off, it is usual to dump

excess fuel or circle to burn it up before landing. Bouncing off the runway tends to happen when planes land too fast. But according to Russian news media, the pilot says he followed the procedure for landing with excess weight and did so at a normal speed. Some of the passengers who escaped the crashed plane were carrying hand luggage, prompting speculation that people retrieving luggage may have caused critical delays during an evacuation in which every second counted. Passenger planes tend to be struck by lightning once a year

on average and are usually unaffected by it, says electrical engineer Manu Haddad of Cardiff University in the UK, who designs protective systems for planes. The fuselage acts like a Faraday cage, protecting those within. All equipment is shielded to prevent lightning inducing currents that could damage it or create sparks that might set fuel alight. “If it’s the lightning that caused this damage, the protection system did not work,” says Haddad. That could be due to a design flaw or to the shielding being compromised for some reason, he says. ❚

More news online Keep up to date with the latest science news www.newscientist.com/news

High cost of UK’s ash dieback THE expected death of nearly all of the UK’s ash trees because of fungal disease will become expensive. The cost of lost ecosystem services and clearing dead trees is now predicted to come to £14.8 billion by the end of the ash dieback outbreak (Current Biology, DOI: 10.1016/j. cub.2019.03.033). “The message is government is not taking plant security seriously enough,” says Nick Atkinson at the University of Oxford, who led the work. Economic cost aside, Atkinson says the death of the native trees will be a major blow for nature. “It’s part of the glue that holds British countryside together,” he says. ❚ Adam Vaughan 11 May 2019 | New Scientist | 7

News Space medicine

Human genetics

Excess brain fluid may cause bad vision in astronauts

Gene variants linked to sudden death in athletes

Leah Crane

Clare Wilson

NASA

In space, gravity doesn’t pull your body fluid to your toes, as it does on Earth

strong enough to be sure it was causing the vision changes common among astronauts. The studied cosmonauts all spent about six months in space, so we don’t know if the effect gets more pronounced with time – a consideration for any long flights to Mars. They were also all men, so we don’t know if the effect would be the same in women. ❚ 8 | New Scientist | 11 May 2019

Sickle cell anaemia alters the shape of red blood cells

EYE OF SCIENCE/SCIENCE PHOTO LIBRARY

ASTRONAUTS who have spent months in space have increased liquid in their brains, which may affect their vision when they return home. On Earth, gravity pulls your bodily fluids towards your feet. In space, that isn’t the case. “That’s why, when you see pictures of astronauts on the space station, they look like they have a puffy head,” says Angelique Van Ombergen at the University of Antwerp in Belgium. She and her team scanned the brains of 11 Russian cosmonauts before and after going to space. When the cosmonauts returned, the volume of their brains’ ventricles – chambers that hold cerebrospinal fluid – had increased more than 11 per cent to hold the extra fluid flowing into their heads. Even about seven months later, the ventricles were more than 6 per cent bigger than before the cosmonauts launched (PNAS, DOI: 10.1073/pnas.1820354116). It isn’t yet clear if this affects brain function. The team found a correlation between the volume of one of the four ventricles and loss of visual acuity, but it wasn’t

A CLUSTER of unexplained deaths of US athletes while exercising could be down to several genes that affect the ability of red blood cells to carry oxygen. The findings could be turned into a test to see if some people are at greater risk of collapsing on the sports field, says Lorena Madrigal at the University of South Florida. The sudden death of young athletes is very rare, and is sometimes caused by an unsuspected heart problem, but being a carrier of the gene variant that causes sickle cell anaemia may also be a factor. Sickle cell anaemia is a genetic disorder that involves having abnormal haemoglobin, the molecule that carries oxygen in red blood cells. Under some conditions, such as physical exertion, these red blood cells can warp into a crescent shape and block blood vessels, causing pain and breathing difficulties.

The disorder is more common in people who have African, Mediterranean and South Asian ancestry, probably because it gives protection from malaria. It was thought that

23

known cases of sudden death in athletes with a sickle cell gene

health problems occur only when a person has two copies of sickle cell gene variants, and that carriers – who have only one copy– had no issues. But some suspect that sickle cell carriers have a higher risk of sudden death during exercise. There have been 23 known cases of this happening to AfricanAmerican athletes who were carriers, according to a registry of such cases going back 31 years, although we don’t know if this gene was responsible. Madrigal has been researching whether particular sickle cell carriers may be more

susceptible to sudden collapse during exercise. She and her colleagues genetically tested 29 African-American college football players who are sickle cell carriers, and asked them about their health. They found that people who had previously collapsed during exercise with pain and fatigue were more likely to have one of two additional genetic variants that affect a different haemoglobin gene (Southern Medical Journal, doi.org/c5cj). The gene is normally active in fetuses, but in some people with sickle cell anaemia it stays active into adulthood and lessens the severity of their symptoms. The team’s work suggests that sickle cell carriers who have less active fetal haemoglobin genes are at a higher risk of health issues during exercise. Madrigal says further studies may lead to a test for predicting which sickle cell carriers have a higher likelihood of collapsing. “At the moment, there’s no way to predict who’s at risk.” However, we don’t know if the 23 athletes who died carried any of the variants highlighted by the team’s study. Simon Dyson of De Montfort University in Leicester, UK, says US colleges should focus on safer training practices, such as avoiding pushing people too hard and protecting athletes from overheating. This would be safer for everyone, because even fit and healthy people can die from heat exhaustion during exertion. “Appropriate precautions for all those undertaking exercise can prevent deaths,” says Dyson. ❚

Animal cognition

Smarter than they look Sharks have a feel for numbers and can learn from each other Ruby Prosser Scully

in the wild, says Schluessel. The reason not all the sharks learned how to do the task could be because they, like all animals, have intellectual differences. Sharks join a growing number of animals that have been discovered to have similar skills at distinguishing quantities, including black bears, guppies and rhesus monkeys. In one

experiment, dogs and wolves were able to reliably pick the larger of two groups. But dogs could only do so when one of the groups had substantially more objects. Some shark species are social learners and can perform a task in a tank more quickly if they watch another shark that has already been trained to do it. This contradicts the image

CHRIS & MONIQUE FALLOWS/NATUREPL.COM

SHARKS may be even more calculating than they seem. They can learn cognitive skills from other sharks and recent experiments reveal they have a grasp of quantity. Vera Schluessel at the University of Bonn in Germany and her colleagues tested how well 12 bamboo sharks could recognise different numbers of objects. Each shark was put in a training pool with pictures of two different groups of geometric shapes projected onto a wall. The team then cycled through at least 40 objects of different shapes and shades to ensure the sharks weren’t simply picking up on the darkness of the objects or the area of wall they covered. Around half the sharks learned to reliably press their nose against the image with the most objects, after which they were rewarded with food. These sharks only seemed capable of picking out the bigger group if it contained at least two more objects than the smaller one. This may be because the difference between six and seven fish or predators is unimportant

of sharks as mindless, solitary creatures. Just like humans, sharks learn from their own experiences and failures. And just as we do, sharks can learn from each other’s experiences too, says Catarina Vila Pouca at Macquarie University in Australia. Being able to learn from others is enormously beneficial. Not only does it save time, but watching another shark’s success at feeding or failure to escape predators could be a matter of life or death. Schluessel and her colleagues have also previously found that bamboo sharks have a sophisticated ability to discern categories, such as snails or fish, enabling them to get a treat even if pictures look remarkably similar. This resembles our ability to look at a goldfish and a salmon and know that they are the same type of thing, even though one is 30 times the size of the other. The team is currently writing up the findings for publication. ❚ Blue sharks may well be intelligent too

Space

Strange asteroid may be spinning itself to destruction THERE’S a new type of asteroid, and it is spinning so fast it is falling apart. The small asteroid has been throwing off debris for at least six years, the most activity we have ever seen from a rock of its type. There are normally two reasons for an asteroid to blow off material: something has hit it or it has ices or chemicals called volatiles, including water, that turn into gas and blow away when the asteroid gets warm.

But (6478) Gault, which is about 4.5 kilometres across and orbits the sun every 3.5 years, seems different. As far as we can tell, it doesn’t have any volatiles. Yet when Colin Orion Chandler at Northern Arizona University and his colleagues examined data from 2013 to now from the National Optical Astronomy Observatory, they found signs of activity in every picture of it. In all the images, the asteroid has a comet-like tail of material behind it, so it appears to be constantly shedding debris – the first asteroid of its type that we

have seen doing so more than once. “This has been happening for a long time, in multiple orbits around the sun and at different distances from the sun,” says Chandler. “It’s a really weird object no matter how you look at it.” He says that this may be due to a phenomenon called the YORP effect, in which sunlight hits the angled side of an asteroid and makes it spin. The faster rotation

“It seems to constantly shed debris — the first asteroid of its type we have seen doing so more than once”

makes the rock shed dust and debris. Eventually, it will probably fall apart completely (arxiv.org/ abs/1904.10530). “If this is a type of object that can mimic something that has water, we need to know why that happens and how it works so we can distinguish between things that have water and things that don’t,” says Chandler. Figuring out exactly what is going on with the rock may help eventual asteroid miners rule out objects like this as targets when they are looking for water and other volatiles in space. ❚ Leah Crane 11 May 2019 | New Scientist | 9

News

Learn how science could help save our planet newscientistlive.com

Climate change

Time for a green revolution A major report on the UK’s climate future shows how the entire country must change Adam Vaughan

“Make no mistake, this report is the most important of our generation” suggested by some politicians and campaigners weren’t credible. The group’s report paints a picture of the dizzying scale of change needed across every area of society. Low-carbon power production will have to quadruple to keep the lights on and clean up other sectors, such as heating and transport. “Crucially, this is technically possible with known technologies and without major changes to consumer behaviours,” says Chris Stark, the committee’s chief executive. New cars should be electric-only by 2030, rather than 2040 as the government currently plans. This should be relatively easy, because cheaper running costs will make them more appealing than petrol and diesel cars in the 2020s. Boilers and heating systems, however, which mostly run on 10 | New Scientist | 11 May 2019

Biodiversity crisis Any efforts to curb emissions have to leave room for nature too. This week, a UN report on biodiversity stated that human activities threaten a million species, and our own future. But it isn’t too late to save them and us. The report is grim reading. We have already significantly altered three-quarters of all land and two-thirds of the oceans. More than a third of land and threequarters of freshwater resources are devoted to crops or livestock.

STEVE PROEHL/GETTY

THE UK’s climate advisers have urged the government to legislate for a world-leading target of effectively eliminating its greenhouse gas emissions by 2050, ending the country’s contribution to global warming. The UK already has a target of an 80 per cent emissions cut by 2050, but the Committee on Climate Change (CCC) said the falling costs of wind farms, batteries and other technology mean the new goal could be achieved at the same cost: about 1 or 2 per cent of GDP. Unlike for other countries that have legislated for a net-zero target, like Sweden, the CCC says aviation and shipping emissions must also be counted. The CCC said it was feasible for the UK to hit net zero by 2050. However, it said earlier dates

fossil fuels today, will be one of the most expensive things to green, at a cost of £15 billion a year. Buildings will require huge and costly efficiency improvements. UK landscapes will have to be redrawn. A fifth of the farmland will need to be converted to ways of reducing and storing carbon. This includes a tripling of treeplanting to 27,000 hectares a year. Such a move could also benefit the nation’s biodiversity (see “Biodiversity crisis”, above). The CCC says targets will also have to apply to greenhouse gases

from livestock and other sources. People in the UK will need to eat at least 20 per cent less beef, lamb and dairy than now, something the CCC believes is very possible based on current trends – it is the equivalent of cutting out about 30 grams of beef or 300 grams of dairy per week. As diets change, the figure could even be as high as 50 per cent, the group thinks. In industry, carbon capture and storage, and the creation of a hydrogen economy – with the gas produced without emissions – will be a necessity. None of this will be

UK in 2050 Given current trends, the UK is expected to still have some big emitting sectors in 2050 (as detailed below). Achieving net zero will require greenhouse gas removal and reduction in demand Aviation

31.5

Agriculture

26.3

Industry

9.6

Waste

6.9

Buildings

4.1

Hydrogen production

3.1

Power

2.9

Surface transport

2.4

Fluorinated gases

2.3

Shipping SOURCE: CCC

1

Million tonnes of carbon dioxide equivalent

Some 700 vertebrates have gone extinct in the past few centuries. Forty per cent of amphibians and a third of coral species, sharks and marine mammals look set to follow. The causes are clear. Our expanding farms and cities are leaving less room for wildlife. Other causes are climate change, pollution, invasive species and direct exploitation of wildlife such as by hunting. Michael Le Page

possible without a significant ramp-up of existing policies and the introduction of new measures. If that all sounds like hardship, there is some good news: the UK should become healthier, because of diet changes, being more active through walking and cycling, and breathing cleaner air. Electric vehicles should make towns and cities quieter and less stressful. “Make no mistake, this report is the most important of our generation,” says Dave Reay at the University of Edinburgh, UK. “If the meticulous expert advice here is heeded, it will deliver a revolution in every facet of our lives, from how we power our homes and travel to work, to the food we buy.” The government says it is considering the report but is yet to commit to the net-zero goal. “This report now sets us on a path to become the first major economy to legislate to end our contribution to global warming entirely,” said UK business secretary Greg Clark in a statement. Stark hopes ministers will commit to the target ahead of a major UN climate summit in September, and legislate before the year is out. ❚

Maths

Space

Ancient Greek way of finding primes gets an upgrade

LIGO spies clash of titans: black hole vs neutron star

Donna Lu

Leah Crane

Ancient Greek mathematician Eratosthenes devised a way to find prime numbers

storage space. It would let you sieve a billion numbers with around 7500 units of memory compared with about 32,000 for the existing method (Mathematics of Computation, doi.org/c5ch). Helfgott’s approach can also be used to factorise very large numbers, breaking them down into prime building blocks. The gains are purely theoretical at this point, because Helfgott hasn’t created an algorithm that would run on a computer. “How much of a difference it makes in practice we will only know once real programmers implement the program and spend time optimising it,” he says. ❚

ANOTHER vast cosmic collision has been spotted by the Laser Interferometer GravitationalWave Observatory (LIGO). This one seems to be between a black hole and a neutron star – the first time we have observed these objects crashing together. Gravitational waves are ripples in space-time that occur when massive bodies move. As these ripples pass through Earth, they stretch and squeeze the fabric of space-time in a way that LIGO’s twin detectors, and the Virgo detector in Italy, can measure to extraordinary precision. On 26 April, all three detectors picked up a new signal. “This is different from everything else that we’ve observed,” says LIGO team member Gabriela González at Louisiana State University. LIGO has seen many pairs of black holes smashing together. It has also seen pairs of neutron stars – the dense remains of dead stars – colliding. This signal was unlike any of those. Instead, it may have been a black hole devouring a neutron star. Automated data analysis puts the odds of this being the case at a fairly low 13 per cent, but it may be more likely than that, González says, given the signal differences. Meanwhile, other astronomers are

using observatories around the world to look for signs of the same event – signals in visible light, radio waves, X-rays and more. These counterpart signals would come from the neutron

1.2bn

Light years between Earth and a neutron star being eaten by a black hole

star as it gets shredded and falls into the black hole. “Just before it merges or gets shredded, the neutron star is going around the black hole with something like the same speed as a kitchen blender,” says LIGO spokesperson Patrick Brady at the University of Wisconsin-Milwaukee. So far, though, astronomers haven’t spotted any obvious matches. “The fact that we haven’t found a counterpart yet would mean that it’s further away, which is more consistent with a neutron star-black hole system,” says González. Preliminary analysis has shown that the LIGO signal is coming from about 1.2 billion light years away. “LIGO wouldn’t see binary neutron stars that far away,” says González. ❚

FOUCART ET AL, CLASSIC AND QUANTUM GRAVITY, 2017

inefficient,” says Harald Helfgott at the University of Göttingen in Germany, who has upgraded the method. His work uses Diophantine approximation, where real numbers – essentially any point on the number line, including decimals – can be approximated by rational numbers – those that can be expressed as a fraction of two whole numbers. Pi, for example, is a real number that can be approximated by the fraction 355/113. This lets Helfgott sieve across a range of numbers at the same time, making the process more efficient. To find all primes less than a number N, the algorithm requires less computer memory – about N1/3(log N)2/3 units of

INTERFOTO /ALAMY STOCK PHOTO

PRIME numbers may have been studied for over 2000 years, but there is always something new to learn. A method for finding primes first devised by the ancient Greek mathematician Eratosthenes in 240 BC has had a 21st century upgrade. Prime numbers are divisible only by themselves and 1, and form the building blocks of all other numbers – multiplying different primes creates the rest of the whole numbers. The Sieve of Eratosthenes, as it is known, lets you find all prime numbers less than a certain number by sequentially sieving out multiples of primes. For example, for the numbers 1 to 100, you would begin by removing all multiples of 2, the first prime number - so 4, 6, 8 and so on. You would then start again from the next smallest number, removing multiples of 3. Each number you begin the process on – a number that hasn’t already been removed – is prime. The sieve works well for finding small primes, but becomes unworkable for very large ones because of the time and computer memory required. In the 1960s, when computers had far less memory than they do now, mathematicians optimised the sieve so that they could find all prime numbers up to a certain number, N, while using only ĭ1XQLWVRIVWRUDJHVSDFH For example, to find all the prime numbers up to 100, an algorithm could store and process numbers in rows of 10. But that isn’t practical for much larger values of N. “You can’t do that for a billion numbers using only 10 units of space at a time, because the algorithm becomes very

11 May 2019 | New Scientist | 11

News Drug development

Hormone therapy may improve some symptoms of autism Chelsea Whyte

Biogeography

Jurassic animals enjoyed cruises around the world HUGE floating logs carried communities of animals on global voyages during the dinosaur era. We have long known of preserved logs up to 14 metres long from the Jurassic period 200 to 145 million years ago. The logs are covered in oysters and crinoids, an animal related to starfish that has a central body with long, feathery arms. 12 | New Scientist | 11 May 2019

Those who had higher levels of vasopressin in their blood before the study showed more of an improvement than the rest. It isn’t clear why this may be, says Karen Parker at Stanford University, who led the study. It could be that children with the lowest natural levels of vasopressin didn’t benefit as much because they would need a higher dose, she says. More boys are diagnosed with autism than girls

The second study tested a vasopressin-blocking drug called balovaptan. Paulo Fontoura of the pharmaceutical firm Roche and his colleagues worked with 223 men with autism, who took either a placebo or a low, medium or high dose of the drug daily for 12 weeks. When the participants were rated on the same scale used to assess the children’s social skills, there was no sign of an improvement. But when a different test was used to gauge their daily living skills, the analysis

suggested that there were some improvements in communication and social abilities that increased in line with the dose of the drug (Science Translational Medicine, doi.org/c494). It is unclear why both boosting and blocking vasopressin signalling appears to have beneficial effects. “The best way for me to reconcile that might be that there’s an optimal band of vasopressin functioning, and you don’t want to deviate too high or too low from that,” says Parker. “We’re not saying by any means that we’re curing something or treating diseases,” says Fontoura. “We’re helping people with certain aspects of their behaviour that they may find challenging.” But some think drugs aren’t necessarily the best way to do this. “Teaching an autistic person ways to signal attention without making eye contact, or non-autistic people ways to communicate more directly, may be effective in improving socialisation without resorting to medications with unknown, long-term effects,” says Zoe Gross of the Autistic Self Advocacy Network in Washington DC. ❚

water, which would weigh it down and cause it to rot. Modelling the flow of water into wood, the team calculated that a log over 10 metres long would stay afloat for at least two years (bioRxiv, doi.org/c49z). If the bark was fairly water-resistant, and was colonised by oysters that provided an additional barrier, such a log could float for 20 years or more. In that time, the crinoids could easily be

carried halfway around the planet. The team also examined one of the best-preserved logs and found that the crinoids clustered towards one end and the bottom. This could indicate that the log was moving through the water. “The crinoids would have chosen an area of least resistance at the back,” says Hunter. Similar rafts still exist in modern oceans, but those in the Jurassic were unusually large and long-lived, says Hunter, partly because several marine animals that break down floating wood hadn’t yet evolved. ❚ Michael Marshall

NICK DAVID/GETTY

TWO separate studies have found that hormone therapy can help communication skills and social abilities in some people with autism. Both studies targeted the body’s system for regulating vasopressin, a hormone known to affect social interactions. In the first study, 30 autistic children aged 6 to 12 were given a nasal spray to use daily for four weeks. Around half were given a placebo spray, while the others got one containing vasopressin. The children’s social abilities were assessed at the start and end of this period by getting their guardians to answer a standard questionnaire. Doctors also rated the children’s social skills using an assessment scale and the children took tests that measured their ability to interpret emotions from facial expressions – a skill often diminished in people with autism. The children who received vasopressin showed a greater improvement in their social abilities than those who received the placebo, as rated by doctors and guardians. They also improved at recognising the emotional states of faces (Science Translational Medicine, doi.org/c497).

Initial studies in the 1960s suggested that these logs were floating rafts that the crinoids had colonised. However, many palaeontologists believed that the logs couldn’t float and that the crinoids must have colonised the wood after it sank in the ocean. Now, Aaron Hunter at the University of Cambridge and his colleagues have shown that the logs could float. Hunter had the idea after fishing for crinoids and realising how light they are. Even adults are “like feathers”, he says. Instead, the key question was how quickly the wood took on

“Crinoids riding certain floating logs could easily be carried halfway around the planet”

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

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

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

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

AVAILABLE NOW newscientist.com/howtobehuman

News Palaeontology

Underwater treasure trove Pristine prehistoric bear fossil from a Mexican cave is analysed Chelsea Whyte

PAUL NICKLEN/NATIONAL GEOGRAPHIC IMAGE COLLECTION

FOSSILS of extinct bears discovered in an underwater cave in Mexico’s Yucatán peninsula have been dated to the end of the last glacial period. The Hoyo Negro cave’s floor is currently 55 metres below sea level, but would have been dry before the glaciers melted at the end of the last glaciation. The water has helped to preserve the remains of various animals, including seven prehistoric bears of the species Arctotherium wingei. Divers have brought up two intact skulls from the cave, one belonging to an ancient bear (pictured), and another from a wolflike animal called Protocyon troglodytes. Collagen in the root of the bear’s teeth suggests it lived 11,000 years ago (Royal Society Biology Letters, doi.org/c492). The findings are helping researchers to fill in the gaps in our understanding of how the animals migrated through the Americas. ❚

Astronomy

Battle of the exomoon that may not exist THAT’S no moon. Evidence for what seemed to be the first moon ever discovered outside our solar system may actually just be a statistical blip. This is the second time that a closer look at the data has failed to show the exomoon, and we may never know if it really exists. In 2017, New Scientist reported that David Kipping and Alex Teachey at Columbia University in New York had spotted a possible exomoon orbiting a planet around the star Kepler-1625 in data from the Kepler Space Telescope. At the time, the researchers said the data was inconclusive and 14 | New Scientist | 11 May 2019

switched to the Hubble Space Telescope to take another look. Meanwhile, new analyses of the Kepler data cast doubt on the conclusion. So when the Hubble observations seemed to spy the signal of a Neptune-sized exomoon, that became the only solid evidence. They show a dip in the star’s light as the planet passed between it and the telescope, and then another, smaller dip attributed to the moon. But according to a new analysis by Laura Kreidberg at the Harvard-Smithsonian Center for Astrophysics in Massachusetts and her colleagues, that evidence isn’t so solid. Kreidberg used the same raw data as Kipping and Teachey, but it was processed separately. “I tried my best to reproduce the

exact steps that the original authors used, and I found that I couldn’t reproduce their result,” says Kreidberg. In her team’s data analysis, the extra, smaller dip in starlight was gone (arxiv.org/abs/1904.10618). It isn’t clear why: the two teams have analysed each other’s work,

“Unfortunately, it’s going to be almost impossible to confirm the moon’s existence in the future” and neither of them has found any specific step that would make the two different – it is an astronomical stalemate. “Neither team was able to identify anything the other team did wrong,” says Kipping. “That’s frustrating.”

Another finding that supported the exomoon hypothesis, the fact that the planet seems to be wobbling, remained solid in Kreidberg’s reanalysis. This kind of wobble is often caused by the gravitational tug of either a moon or another planet. We might never know what is going on because Kipping and Teachey’s request to observe Kepler-1625 with the Hubble telescope again in May was denied. “Unfortunately, it’s going to be almost impossible to confirm this in the future,” says Kipping. For now, it may be time to focus the search for an exomoon elsewhere. “It’s only a matter of time before we find a great one,” says Kreidberg. “I just don’t think it’s this one.” ❚ Leah Crane

Materials science

Analysis Suicide

Cobalt could be harvested from the sea for batteries

Did 13 Reasons Why increase US suicides? The Netflix show was widely criticised for scenes of self harm, but it isn't clear if it influenced suicide rates, says Chelsea Whyte

David Adam

IN THE Netflix show 13 Reasons Why, 17-year-old Hannah kills herself in a scene that shows her suicide. Concerns that it could lead to suicide contagion, in which explicit depictions of self-harm can lead people to copy the method, appear to have been borne out by a new study, but it may not be that simple. Jeffrey Bridge at Nationwide Children’s Hospital in Ohio and his colleagues analysed data from the US Centers for Disease Control and Prevention on suicides in the US between 2013 and 2017. They found a 28.9 per cent rise of suicide rates among children aged 10 to 17 in April 2017 as compared with the surrounding months, and an overall increase in the following eight months compared with the previous years. The rise was statistically significant in boys, but not in girls or adults (Journal of the American Academy of Child and Adolescent Psychiatry, doi.org/c495). “It doesn’t make sense that boys Katherine Langford stars in 13 Reasons Why

NETFLIX

STRINGS of plastic balls dangled in the ocean could gather enough cobalt for hundreds of thousands of electric car batteries. Maha Haji and Alexander Slocum at the Massachusetts Institute of Technology say the system could harvest enough cobalt from the water to make a battery for each of the 250,000 Tesla Model 3s that have rolled off the production line so far. In fact, repurposing 76 unused oil rigs in the Gulf of Mexico could produce enough cobalt for more than half a million electric vehicle batteries every year. Growth in sales of electric cars means global demand for cobalt could outstrip supply for the first time next year, according to the European Commission’s Joint Research Centre. But seawater is swimming with dissolved minerals. The world’s oceans carry about 500 million tonnes of cobalt, dwarfing the 7 million tonnes of known reserves on land. The study proposes filling plastic spheres, each about the size of a beach ball and riddled with holes, with absorbent materials, before dangling them from oil rigs into the ocean. The materials, such as algae or lemon peel, would bind with the dissolved cobalt more than other minerals. Every few weeks, the balls would be dragged in to collect the cobalt (Renewable and Sustainable Energy Reviews, doi.org/c5b7). The technique has already been used in lab tests to harvest uranium. Cobalt is a bigger challenge because its concentration in seawater is about eight times lower. The study doesn’t tackle whether the process could be cheap enough to be carried out on a large scale. However, one way to reduce costs could be to use waste materials, such as recycled plastic bottles, to make the balls. The team says further studies would need to assess the environmental impact. ❚

Romer also studied the show’s would be the ones that would impact, surveying 729 people show this effect,” says Daniel aged 18 to 29 before the second Romer at the University of Pennsylvania, as the show is about season aired to assess their a young woman. “It’s not clear that vulnerability to risk of self-harm, and asked again a month after the would trigger a contagion phenomenon for suicides in men.” show was released. He found that people who stopped watching Girls are more likely to attempt part way through the season suicide than to kill themselves, exhibited higher suicide risk and says John Draper of the National Suicide Prevention Lifeline in New less optimism than those who saw the final episode (Social Science & York, so if the show had an effect Medicine, doi.org/c496). on girls, it wouldn't be apparent But he also found that those in the data the team looked at. Bridge and his team didn’t respond who finished the series reported to requests for comment. Another, as-yet unpublished, study by Steven Stack at Wayne State University in Michigan and his colleagues gauged attention to Rise in suicide rates among US the show on Twitter and analysed 10 to 17-year-olds in April 2017 US suicide rates in April and May lower levels of suicide ideation 2017, the months with the most and self-harm than people who tweets. For boys aged 10 to 19, didn’t watch the show. That may they found an increase in suicide rate of 12.4 per cent, while in girls be because it portrayed the protagonist’s friend coping with they saw a jump of 21.7 per cent life’s challenges, says Romer. compared with previous months. Complicating this analysis is a This is more in line with the time general increase in suicide rates, period in which suicide contagion of nearly 10 per cent, among takes place, and reflects the 15 to 24 year olds during 2017. gender split expected for a show Seasonal effects may also be at with a female lead, says Stack. play – suicide rates peak in the spring, though it is unknown why. It doesn’t have to be this way. Draper says that for every person who dies by suicide, there are another 280 who think seriously about it but don’t kill themselves. The ratio we see on screen doesn’t reflect that reality. “We need to flip the script,” he says. “There’s evidence that shows that if you show people coping through those moments, it is associated with a reduction in suicide rates.” ❚

28.9%

Need a listening ear? UK Samaritans: 116123 (samaritans.org). Visit bit.ly/ SuicideHelplines for hotlines and websites for other countries 11 May 2019 | New Scientist | 15

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News Animal behaviour

Technology

Monkeys seem to turn to each other for solace after trauma

Machines will spot road accidents and strange behaviour in the UK

Clare Wilson

Donna Lu

AFTER a frightening experience, some people like company – and that might go for monkeys too. When a hurricane devastated a small island, its resident rhesus macaques spent more time close to each other in the following months. Known as Monkey Island, the uninhabited island of Cayo Santiago in the Caribbean is home to about 1500 macaques, descendants of animals taken there 80 years ago for medical research. Two years ago, Hurricane Maria hit the region, causing thousands of deaths on nearby Puerto Rico and leaving many people without electricity and water. Most of the trees on Monkey Island were damaged or destroyed. It must have been terrifying for the animals, says Sam Larson at the University of Pennsylvania. A tenth of the monkeys died in the storm and their sources of food and water were disrupted. Before the hurricane, the monkeys were fairly stand-offish

ARTIFICIAL intelligence is being used in the UK to detect traffic accidents by monitoring CCTV camera footage. The aim is for the AI to alert traffic operators about incidents in real time, allowing them to act quickly. This is one of the first instances in the country of AI collecting transport data from public CCTV cameras, says Richard Cartwright of FlowX, a firm that is working with several councils on pilot schemes. The algorithm involved is trained to recognise nine different types of road user, including pedestrians, cyclists, cars and trucks. It will track their motion as they move through each camera’s field of view. This month, Devon County Council started to use the system to monitor live footage from 10 existing cameras. It will look for anomalies such as slow or stationary vehicles, or vehicles travelling in the wrong direction. These will be flagged as potential incidents for investigation by staff who are charged with keeping traffic moving and road users safe. Currently, these traffic operators rely on reports from the police or bus drivers, but these can take 10 to 15 minutes to come through after an accident, says Cartwright. The algorithm will learn the regular traffic patterns at the location of each camera, so that it can recognise normal variations throughout a day, such as rush-hour congestion. A pilot involving one camera has also been agreed with Leeds City Council and FlowX is in talks with five other local

Around 1500 macaques live on Puerto Rico’s Monkey Island

with unrelated individuals. The year after, they were more often seen alongside other animals, even unrelated ones. In one group, monkeys were observed with another within a 2-metre radius up to 10 times as often as before the hurricane. The finding was presented at a meeting of the American Association of Physical Anthropologists in Ohio. Larson says company may have helped relieve stress. Alternatively, a lack of shade from trees may have forced the monkeys to get closer. ❚ 16 | New Scientist | 11 May 2019

ANTONS JEVTEREVS/ALAMY STOCK PHOTO

AI to keep an eye on traffic

authorities around the UK. One challenge in creating the system has been minimising the number of false alerts flagged by the algorithm. “If you have three very similar vehicles driving along the road at the same time, you could get a slow or wrong way vehicle detection, because the software thinks that one vehicle in one frame is a different vehicle in the next frame,” says Peter Mildon at technology firm Vivacity Labs, which is involved with the project. If there are too many false alerts, this could dissuade operators from using it, he says. However, reducing the system’s sensitivity may mean that some incidents are missed. Similar AI-powered traffic monitoring systems have been deployed in China, such as the City Brain project in Hangzhou

The latest developments in AI Keep up to date on bots and their brains online www.newscientist.com/subject/technology

which is run by e-commerce giant Alibaba. Privacy concerns have been raised about schemes like these because the technology can track individual road users as they move through a city. The identifying details of individual pedestrians or cars won’t be stored in the UK pilots. The software only records the path a vehicle takes, what kind of object it is – a car or cyclist, say – and a timestamp. No video footage is being saved by the algorithm, says Mildon. Although the pilot algorithm won’t use number-plate or face recognition, law enforcers and insurance companies may be interested in doing so in the future to identify problematic drivers before an accident, says Emmeline Taylor at City, University of London. That would raise worries. “We know algorithms aren’t perfect. There are real concerns regarding the prejudicial profiling of drivers,” she says. ❚

WHAT IF TIME STARTED FLOWING BACKWARDS?

WHAT IF THE RUSSIANS GOT TO THE MOON

FIRST?

WHAT IF DINOSAURS STILL RULED THE EARTH? AVAILABLE NOW newscientist.com/books

News In brief Space

Closing in on the mystery of how our world got its water

JAXA

EARTH may have formed with its water baked in. Dust samples from an asteroid reveal an unexpectedly large amount of water, and rocks like it may have been the building blocks that made our planet. In 2003, the Japanese spacecraft Hayabusa left for the 500-metre asteroid Itokawa (pictured). It later returned to Earth with dust samples. Itokawa is an S-type asteroid. These are thought to have formed fairly close to the sun, so were expected to have very little water. Because of this, many scientists have hypothesised that while Earth may have been built from S-type asteroids, it got its water later on from wetter asteroids and comets. Maitrayee Bose and Ziliang Jin at Arizona State University analysed two mineral grains brought back by Hayabusa. The result surprised Ecology

Gene editing

MOLECULES that act like off switches for the CRISPR geneediting system may one day make changing DNA in people safer. CRISPR can easily alter genes, and could lead to new treatments for cancers, viral infections and genetic conditions. But as well as desirable changes, it can also make unwanted mutations in DNA, a possible health risk. Amit Choudhary at Harvard University has been looking for compounds that can help us more finely control CRISPR. He and his colleagues say they have identified two molecules that may stop the CRISPR system within minutes. To find these, they analysed thousands of substances, looking for those that could interfere with CRISPR’s ability to bind to DNA – a key requirement for being able to identify and alter genes. The CRISPR system uses Cas9, 18 | New Scientist | 11 May 2019

an enzyme from bacteria, to bind to DNA and then make a cut in its sequence. The most commonly used version of the CRISPR technique uses a Cas9 enzyme that is constantly switched on, which may raise the risk of it binding to other DNA sequences and causing unwanted edits. The two molecules identified by Choudhary and his colleagues interfere with the enzyme’s ability to recognise and bind to DNA. Choudhary says these should allow us to stop the gene-editing process within minutes, thereby reducing the risks of off-target mutations (Cell, doi.org/c493). Larger anti-CRISPR proteins had been developed earlier, but Choudhary says smaller inhibitors are likely to act faster and without prompting an immune response. When he and his team tested their molecules in mammalian cells and human plasma, they found they were non-toxic and didn’t seem to hinder essential genes. Ruby Prosser Scully

Hungry hippos move vital silicon into river BY EATING huge amounts of grass and then defecating in water, hippos are like living silicon pumps – and the health of their habitat may depend on them. Every evening, hippos eat around 40 kilograms of grass and other plants rich in silicon dioxide, also known as silica. The day after, they laze in the water, where they digest and excrete it. To see how the animals move silicon in their ecosystem, Jonas

ANN AND STEVE TOON/GETTY

Discovery could make CRISPR safer

them. “Itokawa is bone dry with respect to anything in our human experience, but it’s wetter than we expected,” says Bose. The asteroid was once part of a huge rock, says Bose. The pair estimate that this would have contained about half as much water as all of Earth’s oceans combined. They also found the water had the same chemical signature as that on Earth, the moon and Mars (Science Advances, doi.org/c49j). This suggests water on all these bodies came from the same place, says Bose: primordial pebbles that formed asteroids and then worlds. In this scenario, there is no need for water to be delivered later on. Two missions at other types of asteroids are due to collect samples that may shed more light on this. Leah Crane

Schoelynck at the University of Antwerp in Belgium and his colleagues looked at silicon levels in a hippo-dominated ecosystem in south-western Kenya. In one 250-metre stretch of the Mara river, they spotted up to 80 hippos. Analysing dissolved and particulate silicon in the river revealed that hippos transported 400 kilograms of the element a day, or 76 per cent of the total moved throughout the ecosystem (Science Advances, doi.org/c488). “Hippos act as a kind of conveyor belt, transporting silica from land to water,” says Schoelynck. This is vital because single-celled algae in the water need silicon, and algae provide food for other plants and animals. But hippos have been killed or driven from most of the rivers that lead into Lake Victoria. If populations shrink further, the amount of silicon pumped into waterways will fall, and plants and fish could be in jeopardy, says the team. RPS

New Scientist Daily Get the latest scientific discoveries in your inbox www.newscientist.com/sign-up Ocean exploration

Really brief

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Fish faeces to fuel submerged drones UNDERWATER robots could charge their batteries by eating the sea floor. A device created by the US Navy extracts electrical energy from fish faeces and other organic matter to provide endless power. All underwater devices have a fundamental limitation – battery life. They are useful for exploring and monitoring the depths, but once their power starts to run low, you have to bring them to the surface or abandon them.

Pandas aren’t as odd as we thought By being picky about their bamboo, pandas manage to gobble as much protein as polar bears. They do this by preferring to eat the shoots to the rest of the plant, which may explain how these vegetarians manage to get by with a digestive system that is better suited to eating meat (Current Biology, doi.org/c5bx).

New guidelines may make it easier to diagnose a recently recognised form of dementia. Known as LATE, the condition appears to involve a misshapen form of a brain protein called TDP-43, which is particularly common in people over the age of 85 (Brain, doi.org/c498).

Young bees inherit disease resistance Bees have been found to pass immunity-boosting molecules to their larvae. Putting specific RNAs in the jelly fed to younger bees appears to provide colonies with a kind of collective immune system. This enables young bees to benefit from resistance built up by older bees (Cell Reports, doi.org/c5bw).

Wildlife

last a few weeks under water. However, one powered by MFCs lasted eight months. In principle, MFCs can provide power indefinitely as the sediment is replenished by the slow fall of fish faeces, dead creatures and other organic debris. The main stumbling block is their low power density. It would take one a day to charge up an iPhone X and around a year to charge a small, uncrewed underwater vehicle. As a result, a large array of MFCs will be required, or underwater vehicles that need much less power. David Hambling Microbiome

Friendly bacteria may curb eczema

AGE FOTOSTOCK / ALAMY STOCK PHOTO

Recognition for new type of dementia

One solution is to use microbial fuel cells (MFCs). These devices incorporate naturally occurring bacteria that can feed on organic matter in the sediment on the seabed, mainly faeces from fish. As they digest this, the bacteria shed electrons, causing a flow of current that can be used to power electronics. Meriah Arias-Thode at the US Navy's Naval Information Warfare Center Pacific in San Diego and her team have already used MFCs to power basic sensors, such as ones monitoring magnetic fields. Previously, these devices could

Narwhals doing swimmingly despite a narrow gene pool THE genetic diversity of narwhals is low, but this doesn’t seem to be hindering them. Such a state of affairs usually makes a population of animals less able to adapt to change. But these Arctic whales, famous for the tusk on their upper jaw, are doing pretty well. This suggests genetic diversity might be less vital than we think. Michael Westbury at the Natural History Museum of Denmark and his colleagues sequenced the genome of a narwhal from west Greenland. Comparing the DNA the narwhal inherited from each of its parents revealed much lower levels of diversity than is normally seen in

Arctic marine mammals, such as the beluga whale (iScience, doi.org/c489). Low diversity is often the result of inbreeding or a small population. But neither fits the narwhal, which numbers around 170,000. The genetics suggest rapid population growth since around 115,000 years ago. Before that, there was a slow decline for about a million years, which might explain why a lack of diversity doesn't seem to be a big deal. A population crash can see important genetic variations lost, but a slow fall may have meant narwhals preserved diversity where it matters. Sam Wong

HAVING a diverse mix of bacteria on your skin could help fight off eczema, suggesting a probiotic ointment may eventually help treat the condition. Eczema affects many millions of children and adults. Previous research has found that they have more Staphylococcus aureus, a common skin bacterium, and that it spreads more easily. To investigate, Richard Gallo at the University of California, San Diego, and his team colonised the skin of mice with S. aureus and studied human skin cells from people with and without eczema. In human cells, they found that S. aureus used quorum sensing, a form of bacterial communication, to release toxins and enzymes that help them break the skin’s barrier to better colonise it. They also found that other bacteria in the Staphylococcus family countered these toxins by secreting proteins that blocked quorum sensing. When the team put peptides isolated from these other bacteria on mice with skin inflamed by S. aureus, this curbed new flare-ups (Science Translational Medicine, doi.org/c487). Gallo says this is a boost for efforts to develop an ointment with friendly bacteria for the skin. Chelsea Whyte 11 May 2019 | New Scientist | 19

News Insight Tobacco

Feel the burn FIRST there were smokers. Then there were vapers. Now there is a tribe of nicotine users so new that they don’t have a name yet. Maybe we’ll call them heaters or smoulders. But if the tobacco industry gets its way, they will become a familiar sight. The new tribe are converts to what are called heated tobacco products (HTPs) or heat-not-burn (HNB) devices. Instead of incinerating tobacco they warm it up, releasing an aerosol of nicotine and other compounds that the user inhales. They have been described as a hybrid of a cigarette and a vape (see “New hotness”, below right). These devices have been on sale for years, but tobacco firms have begun a major PR offensive in the belief that the time is right to win over more consumers. “They’re very busy all over the world. It’s a massive campaign,” says Anna Gilmore of the Tobacco Control Research Group at the University of Bath, UK. Take Philip Morris International (PMI), which makes the leading product on the global market, IQOS (I Quit Ordinary Smoking). Last week, the US Food and Drug Administration (FDA) approved it for sale. PMI says the device, which is already available in 41 other countries and territories, is used by 10.4 million people, the vast majority of them ex-smokers. The company also recently launched a campaign encouraging people to switch from cigarettes. If efforts like these succeed, we can expect a rerun of the health debates that have raged over the e-cigarettes used by vapers. Are HTPs safer than smoking? Do they encourage people to quit, or to start? What are the long-term risks? The answers matter because the tobacco industry is aiming HTPs at smokers, who might 20 | New Scientist | 11 May 2019

REUTERS/TORU HANAI BELOW: KYODO NEWS VIA GETTY IMAGES

The rise of vaping has seen tobacco firms revisit an old cigarette alternative, but the health benefits are far from clear, says Graham Lawton

otherwise quit or shift to vaping. The idea of heating rather than burning tobacco is actually nothing new. The first HTP was launched in 1988 by the R. J. Reynolds Tobacco Company, but flopped commercially and was withdrawn the following year. The industry launched numerous devices after this, but smokers consistently rejected them. These early products were marketed at smokers worried about smell, ash and second-hand smoke. But now the industry has hit on a new idea: to sell the devices as being safer. The logic is that because the majority of

The IQOS heat-not-burn device is stored in a charger that resembles a cigarette case (below)

“Are heated tobacco products safer than smoking? Do they encourage people to quit, or to start? What are the longterm risks?”

dangerous compounds in cigarettes are generated by burning tobacco, ditching the combustion should mean HTPs are less toxic, while still delivering nicotine and a cigarette-like taste. The reason the industry thinks the time is ripe is due to the success of e-cigarettes, says Theodore Caputi, a health economist at Harvard University. These have popularised the idea of safer, smokeless alternatives, but have failed to satisfy many smokers. They often lack the “throat hit” – the sensation of smoke striking the back of the throat – that many smokers enjoy. PMI confirms that vaping’s partial success has created an opportunity. “E-cigarettes have changed smokers’ thinking,” says Moira Gilchrist, head of scientific and public communications at PMI. “But the rate of people switching from smoking to vaping has actually slowed down, so there’s an opportunity to provide other alternatives.” PMI admits that heated tobacco doesn’t eliminate the dangers of smoking. “IQOS is not risk free,” says Gilchrist. “The best thing a smoker can do is quit.” But the firm insists it is less harmful to use a HTP than to smoke. “It is safer,” says Gilchrist. This claim largely rests on PMI research showing that heating rather than burning tobacco generates significantly lower levels of harmful chemicals. It examined 58 compounds found in smoke that are known to be harmful or potentially harmful. Averaged across the 58, levels in IQOS aerosols are 90 per cent lower. An independent literature review by Erikas Simonavicius at King’s College London and his colleagues found broad agreement with this figure. But 10 of the 11 studies on aerosol composition

Working hypothesis

More Insight online Your guide to a rapidly changing world www.newscientist.com/insight

a smokescreen, says Glantz. What matters is the biological effect of inhalation. He says that studies he and others have done, both on PMI data and independently generated results, show that, by this measure, IQOS and other HNB products are little, if any, safer than cigarettes. Another concern is that the aerosol may contain harmful chemicals that aren’t in cigarette smoke because burning breaks them down. “It is possible that HTPs deliver to their users a

10.4m

The number of people using the IQOS heated tobacco device

unique chemical mixture with a distinct toxicity profile,” says Irina Stepanov at the University of Minnesota. This means HTPs could lead to diseases not caused by smoking, says Glantz. PMI accepts that it isn’t sufficient to simply know the aerosol composition, but disputes that the fumes are equally toxic. “We’ve also completed toxicology studies,” says Gilchrist. “All show a

New hotness IQOS, the leading heat-not-burn product, is a handheld device with a slot for sticks of compacted tobacco that resemble very short filter cigarettes. When you insert a stick, the tobacco is pierced by a blade-shaped electronic heating element, which, when activated, KHDWVWKHWREDFFRWRÓ& FRPSDUHGZLWKDURXQGÓ&IRU a conventional cigarette. Inhaling on a filter draws air through the tobacco, producing a nicotinelaced aerosol. The experience is very similar to smoking a mild

cigarette, with a noticeable nicotine buzz and a “throat hit”, but no ash and very little odour. The device isn’t covered by the indoor smoking ban in the UK, but people need permission from the owner to use them in a pub or other venue. IQOS’s main competitors are Glo, made by British American Tobacco, and Ploom, produced by Japan Tobacco. Both launched initially in Japan, where e-cigarettes containing nicotine are illegal, and are now gradually being rolled out around the world.

significant reduction of toxicity.” Up to now, however, PMI has failed to persuade the FDA of the validity of its health claims. Companies wishing to market “safer” smokes in the US have to apply for FDA recognition as a “modified risk tobacco product”. PMI has filed such an application for IQOS, but in January 2018 the FDA’s Tobacco Products Scientific Advisory Committee decided it didn’t reach the required standard. PMI submitted an updated approval last summer. Gilchrist says it is still under review and that the firm doesn’t know when to expect the verdict – the FDA approval last week was to sell the device without making any health claims. In the meantime, independent evidence has begun to pile up. In a review of the literature on heated tobacco published this year, Bertrand Dautzenberg at the Sorbonne University, Paris, and Marie-Dominique Dautzenberg of pressure group Paris Without Tobacco analysed the health claims. “Heated tobacco produces less smoke than traditional cigarettes, but the risk reduction is not demonstrated,” says Bertrand Dautzenberg. The pair also found evidence that non-smokers taking up HNB outnumber smokers using it to quit and that 69 per cent of users continue to smoke as well. Both fly in the face of industry claims that these devices help people to quit. It is still too early to deliver a verdict on the health impacts of HTPs, let alone wider questions such as whether they help smokers quit, but industry observers are sceptical. “Tobacco sales are declining globally,” says Gilmore. “Their long-term business model is under threat. They have to do this.” ❚

▲ Blue Origin Amazon CEO Jeff Bezos is expanding his delivery service with rocket firm Blue Origin. It launched a suborbital flight with 38 experiments, and gravity returned them to sender. ▲ Beach lovers We now have an antidote to the Australian box jellyfish, the world’s most venomous animal. Luckily, it doesn’t involve urinating on yourself (no really, don’t do that). ▼ Honey In a shocking discovery, campaign group Action on Sugar has revealed that honey contains sugar, and isn’t as healthy as the bee lobby has led us to think. ▼ Sausages Food scientists searching for sustainable sources of protein have made sausages from fly larvae. Maybe just go vegan. ▼ Germaphobes The UK has decided against ditching 1 and 2-pence copper coins, which have been found to carry antibioticresistant bacteria. So no change there.

11 May 2019 | New Scientist | 21

TOP: BLUE ORIGIN; BOTTOM: ANDREW PATERSON/ALAMY

they looked at were industry funded, says Simonavicius. “The research findings from the tobacco industry support the tobacco industry’s claims,” he says. Indeed, most of the published research on HNB has been carried out by or funded by the industry. This raises concerns, says Stanton Glantz at the University of California, San Francisco, because “tobacco companies have a record of publishing incomplete or manipulated information”. For example, in 2001, PMI released research – dubbed “project MIX” – showing that including additives such as menthol in cigarettes didn’t boost toxicity. In 2011, Glantz analysed internal company documents released through legal action. He concluded that the data had been massaged to conceal the fact that additives did increase toxicity. Responding to the analysis, PMI’s then chief scientist, Ruth Dempsey, said, “I am of the opinion that their concerns on project MIX are unfounded.” Even if PMI’s claim about HNB’s altered chemical make-up is true, studies of aerosol composition are

Sorting the week’s supernovae from the absolute zeros

Views The columnist James Wong dispels claims we have only 100 harvests left p24

Letters Why do we care what we are made of? p26

Aperture Ground squirrels in the Kalahari desert mob a curious cobra p28

Culture A voyage into a mythical dead world reveals truths about us p30

Culture columnist Helen Marshall on sci-fi that makes light work of complex themes p32

Comment

Us vs the gadgets The UK’s plan to stop household gizmos plotting against us forgets that we are the weakest link, says Chris Stokel-Walker Chris is a journalist based in London and author of YouTubers

JOSIE FORD

Y

OU will soon be able to sleep easy in your bed, knowing that the kettle in your kitchen will no longer be plotting to take over the world. That is what the UK government would have its citizens believe, anyway. On 1 May, it announced plans for laws regulating internet-connected devices – the gizmos that together make up the internet of things (IoT). The legislation, if introduced following consultation, will introduce a labelling scheme to assure buyers that any product given the stamp of approval is safe to connect to the internet. The government is proposing that any internet-enabled device that

doesn’t display the IoT checkmark couldn’t be sold by UK retailers. Manufacturers would be able to attain the checkmark by ensuring that their devices have a unique password not kept on a default, easy-to-guess factory setting (such as 0000), that they would have a public point of contact to disclose any vulnerabilities found and that they state for how long they will provide software updates to patch any vulnerabilities. The proposal comes at the right time. In part, the current furore over Chinese firm Huawei’s involvement in the UK’s planned 5G network stems from an envisioned future of internetenabled consumer gadgets, from

kettles to televisions and voice assistants to washing machines. Worldwide, an estimated 75 billion connected devices are forecast to fill our homes by 2025. That’s 75 billion devices that could be hacked to allow someone to siphon off personal data, for example, or to launch malicious raids such as distributed denial of service (DDoS) attacks that paralyse websites by flooding them with data. This danger is very real. In 2016, before the IoT really began to take off, the Mirai botnet attack infected countless devices and turned them against targets in DDoS attacks. Internet security firm McAfee has highlighted

serious vulnerabilities in smart plugs and digital assistants akin to the Google Home Hub and Amazon Echo. A visit to Shodan.io, a website that trawls the internet looking for internet-facing devices accessible to anyone because they have no security or rely on default passwords, will convince anyone of the merits of tighter regulation. All very smart, then – up to a point. The biggest flaw in the UK government’s plan is that it is just a sticker. Its presence on devices may help raise awareness of the need to keep IoT devices updated to patch vulnerabilities, but experience shows that the average user is unlikely to install every update they are prompted to. If any government is serious about tackling the problem of leaky IoT devices, it needs to recognise that often the problem isn’t the devices – it is us. Manufacturers should be compelled to push out software updates at regular moments. And as much as it might annoy us if we want to sit down with a nice cup of tea and binge-watch Netflix only to find that the kettle or TV is updating, the average user can’t opt out. We are inherently lazy people, and usually don’t fully understand or care how technology works, or why its integrity is important. No single label, no matter how shiny, is likely to fix that. Truly trusting the kettle in the next room will require something more. ❚ 11 May 2019 | New Scientist | 23

Views Columnist #FactsMatter

Are there really only 100 harvests left? Headlines warn that our soil is becoming so degraded that we are heading for an agricultural Armageddon. Can that be right? James Wong investigates

W James is a botanist and science writer, with a particular interest in food crops, conservation and the environment. Trained at the Royal Botanic Gardens, Kew, he shares his tiny London flat with more than 500 houseplants. You can follow him on Twitter and Instagram @botanygeek

James’s week What are you reading? A lot of very dry, academic journals, mainly. What are you watching? Kim’s Convenience on Netflix (while reading the dry, academic journals). What are you working on? Prepping a series of talks, promoting a book, working on a radio show and writing a shiny new column for an amazing science magazine.

This column will appear monthly. Up next week: theoretical physicist Chanda Prescod-Weinstein 24 | New Scientist | 11 May 2019

HEN it comes to science reporting, there are some headlines that are so frequently repeated, so intuitively plausible, so closely aligned to our cultural beliefs, that they can seem like incontrovertible truths. The general public, and indeed many scientists, may fervently believe that these claims reflect the overwhelming scientific consensus. However, sometimes when you dig a little beyond the surface, the evidence underpinning even the most ubiquitous headlines can seem surprisingly shaky. Perhaps the best example of such an assertion is that of an impending agricultural Armageddon, caused by decades of irresponsible farming practices that have degraded soils across the planet (or so the press narrative goes). A quick scan of the headlines reveals that despite the confidence with which these forecasts are proclaimed, the actual timescale to D-Day varies rather widely from story to story. While some report that we have 100 years until the end of our soil’s ability to support farming, citing a University of Sheffield study, others claim that this is a mere 60 years away, referencing a speech at the UN’s Food and Agriculture Organization. Recently, the UK government’s environment secretary even stated that the UK is as little as 30 years away from an “eradication of soil fertility” because we “drench it in chemicals”. If this is indeed a likely end-game scenario, we should probably determine which of these estimates is most plausible as a matter of urgency: 30, 60 or 100 years. So let’s take a closer look at this claim.

Despite dozens of headlines quoting these predictions, surprisingly only one peerreviewed paper from a scientific journal is ever cited as evidence to back them up. This 2014 study from the University of Sheffield compared the soil quality of a range of sites in the English city, including agricultural, garden and allotment soils. Now, before we question whether the results of this single, small study can be extrapolated to represent all of England, let alone the whole UK or even the whole world, let us take a look at their findings: basically, some

“I asked leading soil scientists if they had ever come across such a prediction in published research. Not a single one had”

urban soils in Sheffield are higher in carbon and nitrogen than some nearby agricultural ones. OK, but where is the 100-year statistic? It turns out that nowhere in the study was there any calculation, prediction or even passing reference to the claim. None whatsoever. Perhaps not so much shaky evidence to support this assertion as much as non-existent. Maybe this is the result of a typo and the work is in another research paper? After an 8-hour trawl through the academic journals failed to pull up a single study that even attempted to make this calculation, I contacted six leading soil scientists across

the world to ask if they had ever come across such a prediction in either the published literature or their work. Not a single one had. In fact, the words they used to describe this claim were “bold”, “too Malthusian”, “hardly useful”, “almost insulting” and “I have used this in my soil science lectures to show the students to be wary of headlines!”. Ouch. Does that mean there aren’t real threats to some agricultural soils around the world? Absolutely not. Indeed, all the scientists I spoke to went to great lengths to point these out, where they exist. However, they also highlighted how incredibly complex the calculations needed to make such predictions would be, based on myriad factors, only some of which can be predicted with any reliability, with generalisations almost impossible. The boring reality is that while soils in some parts of the world might be in decline, others are not. Furthermore, while agriculture may be one of the factors driving erosion and nutrient depletion, many modern farming practices such as no-till and synthetic fertiliser applications may actually be helping alleviate (rather than drive) this. In fact, according to many objective measures, modern, evidence-based farming techniques are more sustainable than those of an idealised past. Quite a different picture to that painted by the headlines. Despite the thirst for simple truths in a complicated world, the researchers I contacted agreed that setting such a figure for an agricultural “end-point” would be nigh on impossible, which may explain why no published studies appear to have been able to do so. But this hasn’t stopped the newspapers. Welcome to 2019! ❚

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Views Your letters Why do we care what we are made of?

13 April, p 28 From Mandy Meikle, Woolfords, West Lothian, UK Colin Barras reminds us that our 30 trillion human cells are outnumbered by 39 trillion microbes – a more accurate representation than Thomas Luckey’s 1970 estimate that microbes outnumber human cells 10 to one. But over 80 per cent of the human cells that make up our bodies are erythrocytes, also known as red blood cells. These contain no nucleus or organelles, they are simply packed with haemoglobin, the molecule that transports oxygen and carbon dioxide to and from our tissues. Some might say that they are not true cells at all. But why would anyone care about the ratio of human to non-human cells in our bodies? Consider how many DNA-filled human cells, carrying our genes and presumably contributing to our sense of self, are replicating in our bodies compared with nonhuman cells: just under 7 per cent. In the end, does it matter?

How air pollution may cause teen psychosis

6 April, p 25 From Guy Cox, St Albans, New South Wales, Australia You report a study by Helen Fisher and others linking air pollution from vehicle exhausts with 26 | New Scientist | 11 May 2019

teenage psychosis. You say that it isn’t clear how air pollution might be linked to psychotic experiences. The children studied were born in 1994 and 1995. The fuel additive tetraethyl lead was banned in the UK from 2000. So the children may have had between four and six years’ exposure to lead, which is known to affect the brain. Areas that now have high levels of nitrogen oxides would then have had high levels of lead pollution. From Judith Hanna, London, UK Adam Vaughan is right to note that the correlation between exposure to air pollution and teenage psychosis isn’t proof of causation. One smoking gun, though, is that air pollution is consistently worst in areas where poverty is concentrated, with all the social and psychological stresses it entails. It is extraordinary that the study found that 30 per cent of teens surveyed reported at least one psychotic episode. The editor writes: ❚ We didn’t mention that the researchers did control for poverty. They had no data on lead.

Working hours and mental health

13 April, p 20 From Flora Nuttgens, Wantage, Oxfordshire, UK While discussing the effects of cutting work hours, Michael Le Page quotes a study by Huong Dinh at the Australian National University showing that men with unpaid care commitments could manage about 30 per cent more working hours than women with such duties, without experiencing a decline in their mental health. Such a dramatic disparity surely warrants much closer examination. Were the 8000 participants randomly selected? Were they 50 per cent male and 50 per cent female? Could the difference be attributable to men being less comfortable discussing their mental health than women?

What constituted an unpaid care commitment? There is a big difference between buying groceries and caring for an elderly relative, for example. The type of paid employment and levels of status and remuneration could also have a significant effect on employees’ ability to sustain mental health. Le Page pointed out that to make assumptions about working hours based on male needs is detrimental to women’s interests. It is arguably also detrimental to the cause of gender equality to report differences in possible working hours without a more nuanced analysis.

My relation to religion is different as a woman

6 April, p 36 From Ann Bliss, London, UK Harvey Whitehouse reviews

Want to get in touch? Send your letters to New Scientist, 25 Bedford Street, London WC2E 9ES or you can email us at [email protected]

evidence on religion’s role in human civilisation. But he makes no attempt to distinguish between the differing social needs of women and men. Formal religions are staffed by a ruling elite of men who, I believe, have a fundamental goal of regulating women’s sexuality.

so. It is our leaders who need to be forced to make the necessary laws.

Social engineering to change travel and diet

Smart street lights should set street speeds

Get to Proxima Centauri one small step at a time

13 April, p 32 From Mike Smyth, Bellevue, Washington, US Gilead Amit reports plans to send gram-scale craft to Proxima Centauri. Expecting that these could get a signal back to us is fantasy. The amount of power a 1-gram payload could generate can’t be more than a few watts. For comparison, the New Horizons spacecraft uses a 15-watt transmitter to reach us from Pluto. Plans to get to Proxima Centauri should be incremental. Start with more modest lasers, and much bigger payloads and solar sails. Then work on improving each of the various components.

It isn’t the people who need to be forced

6 April, p 8 From Clive Bashford, London, UK A study investigated what people are willing to do voluntarily to reduce their carbon footprints, and concluded “not enough”. I think people would be happy to do far more if everyone had to do

The only step needed is for governments to stop subsidising meat and dairy. Doing so absorbs the majority of the EU agricultural budget, which itself comprises 40 per cent of the EU budget. Subsidies are also high in the US.

30 March, p 23 From Rosemary Sharples, Penshurst, New South Wales, Australia Adam Vaughan notes that the European Academies’ Science Advisory Council urges the European Union to change its stance on transport, which is that curbing mobility is not an option. Social engineering has given us the transport situation that we have now: they built it, and we use it. But social engineering can bring change. It has often been demonstrated that reducing road capacity reduces the amount of travel. There is no forced curb on people’s mobility. Individuals then decide for themselves how they will change their activities. Most opt to vary their route or travel at a different time. Some go to greater lengths, including changing their travel mode or domicile. From Eric Kvaalen, Les Essarts-le-Roi, France Vaughan suggests caps on personal travel to reduce carbon emissions. But if capped travel could be traded, a rich person could buy travel from poorer people who were happy to accept a market price for it. This would be equivalent to a fuel tax that raised the cost to that price and whose proceeds were distributed evenly. A tax would make everybody happier than the cap method. From Gregory Sams, London, UK Taxing meat to cut consumption is curious: many of us are already taxed in order to make it cheaper.

showed us Goodall’s photos of chimpanzees using branches to catch termites and ants – clearly demolishing what we had learned in class a few weeks earlier, which was that humans are the only species to use tools. If chimpanzees are losing their culture, the idea that they may eventually lose their toolusing skills is very sad.

Woman sniffs dog and observes its epilepsy

Letters, 16 March From Gary Colet, London, UK Sam Edge suggests fitting street lights with motion sensors to save energy. I would go further and provide a rolling corridor of light in rural areas. It would move along ahead of a moving vehicle. This might have the added benefit of “nudging” compliance with the speed limit if the light wave were limited to it.

Meetings with famous primates and cultures

16 March, p 16 From Ed Prior, Poquoson, Virginia, US Your article on chimpanzees losing culture brought back memories. I took an elective course in anthropology as a freshman at the University of Illinois in early 1961, but I had no real interest in the field. One day, our professor came in with a burly gentleman, who he introduced as the anthropologist Louis Leakey, who was travelling to California to announce a major discovery by a student named Jane Goodall. We were astonished as he

6 April, p 19 From Melanie Thompson, Leighton Buzzard, Buckinghamshire, UK I am not at all surprised that Amélie Catala and her colleagues find that dogs can smell when someone has had an epileptic seizure. The reason for this is that I can smell when my dog has had one. My dog’s seizures are generally well controlled by medication, but if he has even a small one, even in the middle of the night, I know because of the telltale smell: an acrid pong like no other. It seems to come from his saliva. Since becoming a dog owner, I have realised that the human sense of smell is better than we realise. ❚

For the record

❚ The sculpture of human figures in the intertidal zone is by Antony Gormley (20 April, p 34). ❚ Rhoetosaurus brownie may sound delicious, but the name of the giant dinosaur is Rhoetosaurus brownei (27 April, p 9). ❚ Galactic brain: Breakthrough Starshot plans to go no further than our closest neighbouring star (13 April, p 32). ❚ The average UK female scientist or engineer now earns 22 per cent less than the average male colleague (30 March, p 45). 11 May 2019 | New Scientist | 27

Views Aperture

28 | New Scientist | 11 May 2019

Like wildlife photography? Visit the Incredible Creatures Feature at New Scientist Live newscientistlive.com/incredible-creatures-feature

Watch that tail Photographer Jen Guyton naturepl.com

THESE Cape ground squirrels in South Africa’s portion of the Kalahari desert are mobbing a Cape cobra that has strayed too close to their burrow. You might expect this to end badly for the squirrels because the snake’s highly potent venom can cause respiratory failure within an hour of being bitten. But the squirrels have a clever tactic to see off the predator. Cape ground squirrels (Xerus inauris) are found across southern Africa. They spend part of their lives underground in labyrinthine burrows that can reach huge sizes and that have up to 100 entrances. But when the squirrels do emerge into the sunlight, the desert is a harsh place. Among their many adaptations to cope with this, are their long, bushy tails that they use as parasols to enable them to spend longer foraging. These tails are also a great way to ward off threats like the Cape cobra (Naja nivea), which mainly eats rodents and small birds. The squirrels approach the cobra, often in groups, puffing up their tails to appear larger and shaking them to frustrate the attacker. The squirrels use their quick reflexes to dodge the snake’s lethal fangs. If successful, the cobra is eventually driven away by the mob. ❚ Bethan Ackerley

11 May 2019 | New Scientist | 29

Views Culture

Hunting the future A profound emotional and intellectual voyage into a mythical dead world reveals truths about our future, says Fred Pearce

Book Underland: A deep time journey

LANDSCAPE essayist Robert Macfarlane has gone subterranean with his latest book, digging deep to understand our planet’s past and future and, he promises, to plumb the very depths of the human heart. In Underland, he travels the world in search of “deep time” in deep places. This is mythology as much as geology, anthropology as much as climatology. He goes not underground or to the underworld, but to the underland, a mythical world of the Sami people of Scandinavia, a mirror-image of our world, inhabited by the dead, said to exist just beneath our feet. Macfarlane is a reader in literature and the geohumanities at the University of Cambridge by day. The academic with mud on his boots starts his journey into the underland by sliding down “the riven trunk of an old ash tree” into a deep, dark limestone cave, to see handprints made by ancients more than 35,000 years ago. Over the next, extraordinary, 470 pages, he follows hermit cave dwellers, miners, palaeontologists and the Thai football team that got trapped in caves last year. He buries the dead, delves into labyrinths beneath volcanoes, surfs underground rivers, abseils into black voids, and walks the sewers of London and catacombs of Paris. He unlocks the vault carved into a frozen mountain beneath Svalbard to house a “doomsday” store of the world’s crop seeds, and descends into mines earmarked to keep our nastiest radioactive waste safe for tens of thousands 30 | New Scientist | 11 May 2019

FREDRIK NAUMANN/PANOS PICTURES

Robert Macfarlane Penguin Books

of years. Hades, he discovers, isn’t just the underworld of Greek myth, where the souls of the dead gather, but also the name of a prospective Belgian nuclear dump. There is plenty of “real” science along the way. Macfarlane talks to mycologists about fungal networks that link the roots of trees in a “wood wide web” of chemical communication. He meets glaciologists in Greenland who are observing past climates by drilling cores of million-year-old ice, while watching as climate change hollows out the island’s ice cap. And he shares trowels with archaeologists excavating Bronze Age barrows, and finds physicists holed up in the silence of a deep mine beneath the outskirts of Hida, Japan, to “hear the birth of the universe” in cosmic rays. Amid the geology of ancient eons, he contemplates what defines the age

Underland entrance: the door to a vault in Svalbard that preserves plant seeds

“Now we have the tools to see backwards and to project the future, we seem hell-bent on ignoring their lessons"

we like to call the Anthropocene. As a winner of literary prizes, Macfarlane is primed to explore inner human space too. He lauds the hallucinogenic power of claustrophobia, introspects in the darkness about the “realms of the dead”, and describes dropping into an iridescent shaft of melting ice in Greenland’s Knud Rasmussen glacier as being like entering “a pore in the skin of an immense creature”. He marvels at the great and the small: at springs bursting from the earth near his home as much as murmurings and fracturings of ice caps as high as mountains. These, like manholes in city streets, cave networks and the entrance to Tutankhamun’s tomb, provide openings to his underland world. Macfarlane has two big hypotheses fuelling his journeys. The first is that by going underground, drilling into the heart of our planet’s deep past, we find ways to understand its future. The second is that, at the same time, we can uncover the essence of what it means to be human. Because, he says, “throughout human history, we have placed in the underland that which we fear and wish to lose – and that which we love and wish to save”. The first contention is persuasive. Through many examples, in which “ice breathes, rock has tides, mountains ebb and flow, stone pulses”, he shows how the exploration of “deep time” provides a radical new perspective on the hidden geological and Earth-system forces with which we meddle at our peril. He goes on to ask: “Are we being good ancestors to the future Earth?” Needless to say, he answers in the negative. There is a profound paradox here. After all, when our species had little scientific ability to understand the past or predict the

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Words to the wise

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Celebrating the wonder of writing leaves room for doubt about its future, finds Simon Ings

Writing: Making your mark British Library, London to 27 August

WRITING is dark magic. Because the written (or carved) word effortlessly outlives the human span, it lets the dead make constant demands. The ancient Egyptians used to channel the divine power of words into spells to animate carved servants called shabti to do their bidding after death. At a new exhibition at London’s British Library, the inscription on one put-upon shabti reads: “Here I am”, ready “when called to work, cultivate fields or irrigate the riverbanks”. As Writing: Making your mark shows: poetry be damned, writing is all about control. In the dialogue Phaedrus, composed around 370 BC, the philosopher Socrates complains that writing things down will “create forgetfulness in the learners’ souls, because they

will not use their memories… they will be hearers of many things and will have learned nothing”. Our current worries over trust, authority, truth and fake news feed Socrates’s suspicion that the written word makes us shallow, and less than we might be: a society earnestly conversing with itself. The exhibition does its best to win us over with its celebration of a technology that’s a bit under five millennia old. Here you will find everything from carved slabs to the first use of an italic typeface (pictured). It is thoughtful and eye-catching. Best of all, the show makes narrative sense: we learn how writing and printing evolved independently at different times and places, to fulfil changing social and cultural functions. But in the final room, on the future of writing, the curators may have woken up to doubt – about new media undercutting our written culture. I am surprised. After all, written and printed forms are proliferating. Emoji have given us a whole new writing system to combine with our current languages. Instagram, once full of unadorned selfies, sparkles with photos smothered in animated annotations and one-liners in a form so new it hasn’t really got a name yet. Writing remains one of our most plastic forms of selfexpression. How strange that a show that does such a great job of bringing past writing to life, from Roman shorthand to James Joyce’s multicoloured notebook maunderings, should stumble at this present-day hurdle. ❚ Italics first appeared in print in 1501, in this pocket edition of Virgil’s poetry

Exponential View is Azeem Azhar's podcast about how the more speculative sides of technology will affect our society. Guests include luminaries from the worlds of business, politics and academia. Play

Road to Guangdong explores the tension between old and new in 1990s China, through the prism of a family road trip in a clapped out car. This enchanting journey is available on PC from 16 May. Visit

Food: Bigger than the plate at London’s V&A probes the future of food from farm to fork (or from hydroponic pod to wrapper). Over 70 projects are featured, alongside objects from the collection. From 18 May.

11 May 2019 | New Scientist | 31

FROM BOTTOM: CAROLIEN NIEBLING,THE SAUSAGE OF THE FUTURE PHOTO NOORTJE KNULST, EXCALIBUR GAMES, THOMAS TRUTSCHEL/ PHOTOTHEK/ FALLING WALLS.

Fred Pearce is a consultant for New Scientist

Exhibition

© BRITISH LIBRARY BOARD

future, we were ruled by moral imperatives built on deep memory that instilled obligations about long-term stewardship of our environment. We were good ancestors – or at least as good as we could be in the circumstances. But now that we have the tools to see backwards and to project the future, we seem hell-bent on ignoring the lessons they offer. Even someone with Macfarlane’s powers can’t disentangle this paradox. Perhaps as a result, his second contention, that by exploring ideas about underland we can uncover the human heart, is made less persuasive. Here, his explorations sometimes descend into empty metaphor. Even when they are accompanied by the fictional journeys of fellow underland writers from Jules Verne and Lewis Carroll to Virgil, “digging deep” can appear shallow. And some may find Macfarlane’s lyricism irritating. If you bristle at his early gambits that “darkness might be a medium of vision”, and that his descent into the bowels of the Earth “may be a movement towards revelation rather than deprivation”, you could be among them. But when embarking on any long journey, you need to know that you will enjoy the company of your companion as well as the itinerary. And here you will be travelling with a considerable polymath, as willing and able to quote a Nature paper as Edgar Allan Poe, and to discuss the finer techniques of caving as surely as the physics of dark matter. The bottom line is that if you enjoy Macfarlane’s style and intellect, as I do, you will enjoy the long journey into the underland. ❚

Views Culture The sci-fi column

Fears for the future From the nature of faith to the boundaries of mind, some ideas beg to be explored more than once. Helen Marshall discusses two writers who, in their different ways, make light work of complex themes

Helen is an editor, awardwinning writer and senior lecturer at the University of Queensland, Australia

Books Frankissstein: A Love Story Jeanette Winterson Jonathan Cape

Exhalation Ted Chiang Knopf

Helen also recommends... Will Wiles's surreal and apocalyptic take on the London novel, Plume, is a timely exploration of the nature of truth Chen Qiufan's debut novel, Waste Tide, translated by Ken Liu, is an accomplished eco-thriller full of soiled and toxic beauty

32 | New Scientist | 11 May 2019

UNIVERSAL PICTURES/CAPITAL PICTURES

Meet thy maker: Colin Clive and Boris Karloff in Frankenstein (1931)

WHEN literary novelists try their hand at science fiction, the results can be mixed. Refreshingly, Jeanette Winterson’s Frankissstein: A Love Story is a wildly inventive reimagining of one of science fiction’s most beloved stories. Published a year after the bicentenary of Mary Shelley’s Frankenstein, the novel offers parallel stories of “future fear”. One is a fragmented, fictionalised account of Shelley’s life set against the backdrop of the Industrial Revolution and its attendant horrors. In it, Mary Shelley's stepsister Claire Clairmont taunts her lover, the moody poet and literary celebrity Lord Byron, with the possibility of a mechanical loom capable of writing poetry. Later, Byron’s daughter, Ada Lovelace, dreamily contemplates a computer as big as a city, capable of housing (and mimicking) all strains of human life. Alongside this story runs a modern-day narrative in which transgender surgeon Ry Shelley assists tech savant Victor Stein in his attempt to create an artificial intelligence. It is

populated with eccentrically reworked characters from Shelley’s life: Ron Lord, the venereal AI sexbot manufacturer; Polly D, an investigative journalist (a play on John Polidori, Shelley's friend and inventor of the modern vampire story); and Claire, this time round the organiser of a World Barbecue Cooking Contest.

“What is the mind? Where does the physical end and the spiritual (or indeed intellectual) begin?” The novel careers wildly between different styles, at times lyrical, gloriously raunchy, pulpy and absurd. But in Winterson’s hands, a strange amalgam emerges. What is the mind? Where does the physical end and the spiritual (or indeed intellectual) begin? How do our bodies shape our experiences? What is love? If the future of AI frightens some characters, whether they live in the past or in Winterson’s twisted

present, others find unexpected consolations in the prospect of artificial companionship. Even the coarsest of Winterson's cast prove themselves capable of contributing to the conversation. Exhalation, the second collection of previously published short stories (and two originals) from Ted Chiang, whose “Story of Your Life” was thoughtfully adapted for the screen as Arrival, also moves with ease between the scientific and the fantastical. “The Lifecycle of Software Objects” follows a former zookeeper, Ana Alvaredo, as she raises an intelligent digital pet over a period of 20 years. Chiang avoids dystopian temptations, preferring instead a clear-eyed and even-handed reconnaissance of new technologies. Alvaredo’s relationship with her “digient” raises ethical questions about the nature of sentient life, and the existential threat posed to artificial life by technical obsolescence. “Omphalos”, by contrast, a story original to this volume, eschews realism to imagine a world in which the dating of trees reveals a universe created by God at a fixed point in history. But an astronomical discovery shakes the world’s faith, and forces its devout protagonist to conjure up new and valid reasons to keep going. These are two stand-outs of an impressive collection. Winterson’s novel blazes with fireworks; Chiang’s work is more restrained. Surprising tenderness and force of feeling emerge from his seemingly affectless prose. Exhalation provides startling ways to imagine the future – and, crucially, finds a place for humanity there. ❚

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Features Cover story

Solving the greatest mystery in astronomy Fast radio bursts from across the cosmos have perplexed us for over a decade. Now we might know what they are, says Daniel Cossins

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MINOR point of interest regarding the Spitler Burst.” The subject line Paul Scholz had chosen for his email was deliberately dry, but the recipients knew instantly what its contents meant. He was sitting on a revelation that would blow open the biggest mystery in astronomy. It was 5 November 2015 and Scholz, then a graduate student at McGill University in Montreal, Canada, had spent years scouring data from the world’s largest radio telescope. Staring back from his computer screen was the usual parade of curving lines, each a potential flash in the night sky. Suddenly, Scholz realised one of them looked familiar. A millisecond pulse of radio waves was blasting from a faraway galaxy with the intensity of 500 million suns – and not for the first time. “It was immediately clear this was something staggeringly important,” says Shami Chatterjee, an astronomer at Cornell University in New York. For a decade after the first discovery of these signals, known as fast radio bursts (FRBs), we had no idea what could be producing them. Suggestions ranged from colliding neutron stars to black holes turning themselves inside out to lasers from alien spacecraft. Until a few months ago, we had more ideas than detections. Since Scholz’s email, however, the hunt for the source of FRBs has been moving briskly along, with new clues pointing the finger at an unusual suspect and the latest radio telescopes promising fresh leads. Even if the exact cause isn’t identified soon, these mysterious blasts can still help illuminate the universe, giving us a glimpse at what lurks in the darkest, most distant voids of the cosmos. FRBs aren’t rare. They are raining down on us all the time from all directions. We only missed them for so long because they disappear almost as soon as they appear. Duncan Lorimer at West Virginia University

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34 | New Scientist | 11 May 2019

and student David Narkevic were the first to find one, in 2007. This was actually six years after it was inadvertently detected. The two were searching archived radio telescope data for an entirely different phenomenon – rotating stars known as pulsars – when they saw a signal that struck them as odd. Lasting less than 5 milliseconds, the so-called Lorimer burst is estimated to have released as much energy as the sun spits out in a month. That wasn’t the only curious thing about this signal. Its higher-frequency waves arrived a fraction of a second earlier than its lower-frequency waves, giving it a strange smeared-out appearance, like a rainbow of light emerging from a prism. This smearing, caused by the scattering of light off electrons and other particles, is known as dispersion. The more of it you measure, the more material the radio signal has passed through and the further it has travelled. It is essentially an inbuilt distance marker. Based on the dispersion measure for their signal, Lorimer and his colleagues estimated it had arrived from a galaxy several billion light years away. If you think that sounds ludicrous, you are in good company. The signal was so incredibly powerful, and apparently so well-travelled, that many astronomers had a hard time believing it was real. But in the past 12 years, radio telescopes have picked up dozens more of these FRBs, all with dispersion measures indicating extragalactic origins. And yet there has been precious little consensus about what generates them. “It’s rare to be presented with a mystery like this,” says Emily Petroff, an astronomer at ASTRON, the Netherlands Institute for Radio Astronomy. “These things are so short and seem to be coming from so far away that the engine behind them must be something we have no analogue for in our galaxy. Whatever it

Daniel is a features writer at New Scientist specialising in the physical sciences

is, we haven’t seen anything like it before.” With so few examples to draw on, there is only so much we can know. While a dispersion measure gives you a rough estimate of distance, it doesn’t allow you to pinpoint host galaxies. That is why Scholz’s discovery in 2015 was such a big deal. With a repeating signal (a “repeater” in FRB astronomy circles) you can go back to the position with higherresolution telescopes and more accurately locate the source. That is what Chatterjee and his colleagues did in the wake of the email sent by Scholz, who is now at the Dominion Radio Astrophysical Observatory near Penticton, Canada. Having convinced the Very Large Array radio telescope in New Mexico to take the gamble of giving them observing time, they staked out the relevant patch of the sky. For the best part of 100 hours they watched and waited and saw nothing. And  then, FLASH! It came again, another signal from the same spot. This was the Spitler burst, named after astronomer Laura Spitler, who first saw it on 2 November 2012. It is officially known as FRB121102. Since we began regular monitoring of it four years ago, it has made hundreds of >

ANDREA UCINI

11 May 2019 | New Scientist | 35

Hear more about fast radio bursts Emily Petroff will be speaking at New Scientist Live, which runs from 10 to 13 October in London. For more details newscientistlive.com

Time to CHIME Even with the Spitler burst flaring again and again, there wasn’t enough to go on. So in early 2019, astronomers the world over were thrilled when it was announced that a new kind of telescope called the Canadian Hydrogen Intensity Mapping Experiment (CHIME) had turned up a fresh lead, even before it had properly switched on. CHIME was designed to create threedimensional maps of hydrogen gas in the early universe, which glows faintly at radio frequencies. While it was being erected in a wooded valley near Penticton, FRB chasers realised that it would also be perfect for hunting their quarry. What sets CHIME apart is its wide field of view. Whereas most radio telescopes study a small portion of the sky, this one scans the entire northern celestial hemisphere every day. That generates an unprecedented avalanche of data, one that is impossible to sift through without the help of cuttingedge algorithms. By the summer of 2018, the telescope was in a pre-commissioning phase, meaning it wasn’t fully operational. Components were 36 | New Scientist | 11 May 2019

still being installed and the system was operating at a fraction of its design capabilities. Hence everyone’s surprise when, amid the organised chaos, FRBs showed up. Thirteen of them, taking the running total to 65. “That was a big celebration,” says Victoria Kaspi at McGill University, who leads the CHIME collaboration. Then at the start of 2019, the champagne corks were popping again. “We kept track of what we were seeing and then somebody noticed there were two in the same position,” says Kaspi. Out of nowhere, we had a second repeater. The new repeating signal, known as FRB180814, showed that the first repeater wasn’t a fluke. Given we had found another

Mysterious origins Five theories for where the enigmatic space signals known as fast radio bursts (FRBs) might come from:

Cosmic shrapnel

in the very first batch of bursts CHIME had detected, repeaters might even be common. More important, however, was a striking similarity between the two signals. Each had a series of sub-pulses that shifted down from higher to lower frequencies as they passed through the detectors. This downshift was so similar that when CHIME researchers presented their results at a recent conference, they briefly fooled their audience into believing they were looking at the wrong signal. That similarity makes it more likely that the high magnetic fields Hessels had detected were a product of the FRBs’ origin, rather than the journey they had taken. Right now the prime suspects for that origin are magnetars, young neutron ANDRE RECNIK,DUNLAP INSTITUE,CHIME

appearances. The timing of its bursts seems to be random. Even so, astronomers have been able to use them to figure out where the signals originate. As Chatterjee and others reported in January 2017, they come from a dwarf galaxy some 3 billion light years from Earth. More clues to its true nature followed a year later, when Jason Hessels at the University of Amsterdam and his colleagues looked more closely at the way the repeater’s radio waves twisted as they propagated through space. Known as Faraday rotation, this effect is caused by magnetic fields. Initially they found nothing. But when they widened the search to  look for more extreme effects, they struck gold: the rotation measure for FRB121102 was so absurdly large, it suggested the involvement of magnetic fields many times stronger than anything in our own galaxy, including the supermassive black hole at its centre. Astronomers were now eyeing the usual suspects, including incredibly powerful black holes (see “Mysterious origins”, right). But there was no way to know which of them was responsible, or if they were somehow in cahoots. Then there was the nagging doubt that the extreme magnetic fields the FRBs encountered might have come from something on their route to us, rather than their origin.

Although collisions between hefty astronomical objects can’t explain repeating FRBs (see main story), one-off events could potentially be traced back to such smash-ups.

Black holes Every galaxy has at its centre a supermassive black hole. As they gobble gas and dust, they sometimes fire out beams of radiation that could interact with particles to produce FRBs.

Lost comets It is possible that a comet caught up in the gravitational pull of a small and incredibly dense star could break apart and emit radio waves.

Aliens Some theorists have suggested FRBs could be the result of radio beams used to power light sails on alien spacecraft.

White holes If black holes eventually turn inside out, spewing out matter rather than sucking it up, they might release trapped matter in a way that generates FRBs.

The CHIME telescope in Canada will revolutionise FRB astronomy

stars  that are the universe’s most powerful magnets, generating fields millions of billions of times stronger than Earth’s. They spew out electrons and other charged particles, accumulating a vast cloud of orbiting debris. According to a model developed by Brian Metzger at Columbia University, New York, and his colleagues, this is a perfect recipe for FRBs. As the material in every fresh flare collides with the highly magnetised cloud, shock waves excite electrons at the cloud’s outer edge in such a way as to produce brief flashes of radio waves.

Incredible magnetism This scenario not only produces randomly timed repeating bursts like those we have seen, it can also account for the distinctive downshift seen within individual signals. “As each shock wave slows down, so the radio signal we see shifts to lower frequencies,” says Metzger. But there is more. We don’t yet have a rotation measure for the second repeater, but the first one’s absurdly high reading fits nicely with the magnetar theory. Taken together, this is pushing many researchers in the same direction. “The magnetar model is the one people are feeling good about,” says Petroff. Well, not all people. Although most think the substructure of the repeating FRBs is telling us something about the emission mechanism,

Some theorists believe fast radio bursts (FRBs) are produced by high strength magnetic fields. That points the finger squarely at a class of neutron stars known as magnetars, with magnetic field strengths millions of billions of times stronger than the Earth’s

Earth’s magnetic field:

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1,000,000,000,000,000 others still believe it could be the result of material the bursts pass through as they zip across the universe. It is also possible that there are several sources – that one-off bursts have different origins to repeaters. “People are getting more comfortable with the idea that you don’t need one theory,” says Petroff. In any case, the nice thing about the magnetar model is that it makes observational predictions. First, any FRBs we see in future should carry the same frequency downshift pattern. Second, they should be coming from the sorts of galaxies that are known to be producing lots of young stars and fresh magnetars. “If we look at these sorts of places and constantly find FRBs, that would give us confidence,” says Chatterjee.

Gauss

What we need now are more bursts, and we are about to get them in spades. Once it is properly up and running this year, CHIME should spot several per day. Then there is the Australian Square Kilometre Array Pathfinder, a network of 36 radio dishes capable of pinpointing host galaxies even for one-off FRBs. “The enterprise of FRB searching is entering a new phase,” says Chatterjee. “It is going to be amazing.” But the story won’t end there. If we can gather a sufficiently large sample, the hope is that FRBs will be able to answer some intriguing fundamental questions about the history and structure of the cosmos. One of these is called the missing baryon problem – the apparent absence from the

universe of a large chunk of ordinary matter. Made of particles called baryons, this matter should make up 5 per cent of the universe. The rest is dark matter and dark energy. But so far, we have only been able to spot half of it. Most people think the rest is hiding in vast expanses of empty space between galaxies. The trouble is, we don’t have instruments sensitive enough to probe these voids, particularly as whatever they contain must be extremely wispy. But because FRBs’ epic journeys across space take them through some of the universe’s darkest corners, they should be able to act as probes into these mysterious cosmic voids. Herein lies the beauty of the radio bursts. By encoding information about the medium through which they pass, they can help us to figure out how much ordinary matter these voids contain – a measurement no other probe  can take. “Diagnosis of the baryonic distribution of the intergalactic medium will be the pièce de résistance of FRB science,” says Jean-Pierre Macquart at Curtin University in Perth, Western Australia. Just as tantalising is the prospect that detailed study of FRBs’ twisted radio waves will tell us about the strength of magnetic fields in distant voids. At present, our knowledge of these fields is virtually nil. An accurate measurement may tell us whether they were present in the earliest moments of the universe and, if so, what role they played in shaping how it looks today. “If we can prove that magnetic fields were there during inflation, this period of expansion immediately after the big bang, then they must become an essential ingredient of any cosmological theory,” says Franco Vazza at the University of Bologna in Italy. Not that such measurements will be trivial. FRBs are produced by an incredibly powerful cosmic object and encounter all manner of matter along their way, all of which contributes to the dispersion and rotation measures we read off when they reach Earth. The challenge will be to disentangle the different components, which will only become possible once the new generation of radio telescopes detects a deluge of FRBs. “These things have been going off under our noses for years, and we deduce that there are a few thousand of them raining down on Earth every day,” says Macquart. “They’re an amazing cosmic whodunnit. But even if we never figure out what is producing them, they give us a whole new way to study the universe. It’s a good time to be an astrophysicist!” ❚ 11 May 2019 | New Scientist | 37

IAN CHENG, INSTALLATION VIEW, SERPENTINE GALLERY, LONDON (6 MARCH – 28 MAY 2018) © 2018 HUGO GLENDINNING

Features The big question

Can AI ever be truly creative?

38 | New Scientist | 11 May 2019

Deciding whether artificial intelligence can one day make great art demands a deep dive into human consciousness, says Marcus du Sautoy

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N OCTOBER 2018, a portrait of Edmond Belamy sold at Christie’s in New York for $432,500, nearly 45 times its maximum estimated price. Nothing that out of the ordinary, perhaps. Except Belamy didn’t exist. He was the fictitious product of the artist’s mind – and the mind that created him wasn’t even human. Signed in the corner by a formula that is part of the algorithm that created it, the portrait was the first artwork made by artificial intelligence brought to auction. There have been many similar seeming breakthroughs in AI creativity. In 2017, an AI wrote a continuation of the Harry Potter books by using machine learning to analyse the first seven volumes of J. K. Rowling’s output. The music for US singer Taryn Southern’s 2018 album I AM AI was bigged up as having been composed and produced entirely by machines. Back in 2016, SACEM, a French professional association in charge of artists’ rights, was the first to acknowledge an algorithm, the Artificial Intelligence Virtual Artist or AIVA, as a composer. It fits into a common theme that anything we can do, AI can do – and probably better. But it is worth looking under the hood of all these creative outputs to understand how much the machines really are doing, and how much is just hype. Answering the question of whether AI can be creative isn’t easy – and raises fundamental questions about the nature and origins of human creativity. Ever since the 1840s, when Ada Lovelace became obsessed with the possibility that Charles Babbage’s Analytical Engine, a proposed mechanical computer, could do more than simple computations, we have been contemplating the idea that it isn’t just biological life that may be creative. Recognising that music is an art form similar to mathematics in its manipulation of pattern, Lovelace speculated “the engine might compose elaborate and scientific pieces of music of any degree of complexity or extent”.

It is fairly easy to discount or at least qualify many claims of AI creativity today. Just as, at the turn of the millennium, companies wishing to make it in the tech boom would indiscriminately tag .com on the end of their names, today businesses and individuals are using the labels “AI” or “Deep” to jump on a bandwagon. Much of what they are doing involves little more than data science and statistical number-crunching, and requires a lot of human intervention. The Harry Potter “writer”, for example, relied on a statistical analysis of J. K. Rowling’s existing oeuvre to suggest possibilities for the next words, but a human still chose which words to use. A new tale created by humans with the aid of some computational data science just isn’t as good a story, however. Similarly, Southern got more press traction for her album by bigging up the novelty of a contribution from AI. That isn’t to say that there aren’t some striking examples of AI potentially demonstrating true creativity. Take move 37 of the second game in the titanic battle of Go between the human champion Lee Sedol and the DeepMind algorithm AlphaGo in March 2016. Lee had already lost the first game, but many commentators felt this was because he had tried to play unconventionally to disrupt AlphaGo’s dependence on learning from previous games. But in the second game, it was AlphaGo that tore up the rule book. Having made the 36th move, Lee had retired for a quick cigarette break. Not requiring the same stimulation, AlphaGo thought a while and then asked its human representative to place a black stone on the line five steps in from the edge of the board. Conventional wisdom says that during the early part of a Go game you play stones only on the outer four lines, and so prepare the ground for an assault on the central part of the board later. Lee flinched when he returned and took in the move. But as the game played out, rather than being a mistake, that stone turned out to be the key to establishing control of the >

“How much are creative machines really doing – and how much is just hype?”

11 May 2019 | New Scientist | 39

AI art: Portrait of Edmond Belamy (left); Ian Cheng’s BOB (title page)

“The value of AI might come not so much in making machines that act like humans, but stopping humans acting like machines” @OBVIOUS_ART

Creative or not? The crucial 37th move in a Go game by the AI AlphaGo was hailed for its originality (right); Marcel Duchamp’s notorious urinal artwork Fountain (far right) sparked a debate over the meaning of art

board, ensuring AlphaGo its second victory. Human competitors have since aped AlphaGo’s tactic to establish a competitive advantage. The AI’s discovery taught the world a new way to play an ancient game. For me, this clears some of the key hurdles AI must leap if it is to be deemed truly creative. A basic definition of a creative act might be one that is new, surprising and has value. A computer can easily be programmed to produce novel outputs, but those second two criteria are more challenging. Who is being surprised, and how does one decide value? Move 37 certainly surprised the Go experts, and ultimately it had value: it won the game. It is easier to determine value in a game situation than in other creative spheres, however. An AI’s worth is generally judged by its ability to solve problems, but creating art isn’t a problem-solving activity. The monetary value of the Edmond Belamy portrait came about partly because it was created by an AI, not through some independent assessment of its artistic value. It is rather like Marcel Duchamp’s notorious artwork Fountain, submitted signed R. Mutt to a US art display in 1917. Consisting of a urinal lying on its back, it was valuable less for what it was, than for the questions it raised about what we mean by art. The AlphaGo story demonstrates another way AI can help to create a sort of value, one that does apply in other areas of creative endeavour. It comes not so much in making machines that act like creative humans, but in stopping creative humans behaving like machines. We can get terribly stuck in our 40 | New Scientist | 11 May 2019

ways of thinking: as a Go player, your master would have slapped your wrist if you placed an early stone on the fifth line. An AI’s unprejudiced exploration of the terrain, meanwhile, can sometimes reveal new pinnacles of achievement. You may be at the top of Snowdon, thinking you have reached the ultimate height, but that is because you don’t know Mount Everest exists.

Musical Turing test Many of the examples of music created by AI are still stuck in the foothills, comprising poor pastiches of Mozart or Beethoven’s works. But there are examples where code has helped us cross the valley to more interesting peaks. The Continuator, a jazz improvisor designed by François Pachet, director of the Spotify Creator Technology Research Lab, provides another example of how AI can help us escape the straitjacket of creative conventions. He trained his algorithm on the music played by jazz musicians. One of the standard modes of jazz is a call and response in which one player riffs and a second reacts. By analysing how one phrase of music mutated into another, the Continuator came up with its own responses to the riffs that make up a jazz musician’s sound world. When musicians improvised with the Continuator, they were amazed. The algorithm was passing a kind of musical Turing test, responding in a way indistinguishable from a human improvisor. And its responses weren’t simply a mash-up of what had gone before: the

musicians could hear the Continuator playing things that were recognisably connected with their style of performance, but which they never thought possible. It was taking the music to a new and unexpected level. It was as if the humans were playing in a huge hall but only in one small, illuminated corner – then the AI had thrown the lights on and shown them the whole space available to them. Pachet is currently working on Brazyle, an AI that aims to do something similar for Brazilian music. Although novelty, surprise and value are three key components to measure if AI is being creative, I think a fourth element must also be introduced if we are going to herald real creativity in AI: originality of a truly independent nature. Lovelace herself raised it all those years ago as she wrote about Babbage’s machine. “It is desirable to guard against the possibility of exaggerated ideas that might arise as to the powers of the Analytical Engine,” she wrote. “The Analytical Engine has no pretensions whatever to originate anything. It can do whatever we know how to order it to perform.” Ultimately, she believed, you couldn’t get more out of the machine than you had put in. This raises a crucial question: how much of any AI’s “creativity” is the creativity of the human coder rather than the code? Cameras heralded a new age of human creativity that can be seen displayed today in art museums across the world. But no one assigns the camera any part in the act of creativity. But that is an imperfect analogy. Humans are machines running the instructions of a

The creativity code Hear Marcus du Sautoy talk about AI at New Scientist Live newscientistlive.com

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Marcus du Sautoy is a professor of mathematics and the public understanding of science at the University of Oxford. His book on AI and creativity, The Creativity Code, has just been published (Fourth Estate)

JOHN CAIRNS

code, our DNA. Our parents are responsible for that code, yet we don’t regard ourselves as a mere vessel for the creativity of our parents. Part of how a child differentiates itself from its parents comes from its unique interaction with its environment. This interaction also shapes our creative abilities. And that is exactly what is happening with AI. Machine learning allows code to change, mutate and update itself based on its interaction with new data: inputs from the environment. In creative terms, the potential result is shown by a work from the artist Ian Cheng displayed at the Serpentine Gallery in London in March 2018. He started off with six artificial life forms, all called BOB and all written with the same code. But the parameters of each BOB’s code mutated

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DUCHAMP: FOUNTAIN, 1917. MARCEL DUCHAMP’S READYMADE SCULPTURE, ‘FOUNTAIN,’ SIGNED BY R. MUTT, 1917/ALAMY

depending on interactions with gallery visitors. At the end of the show, after months of different interactions, the six BOBs were very different beasts. This shift from top-down to bottom-up coding gives code the chance to assert an independence from its architect. You could argue that Cheng was still the ultimate creative author, because he was the one who gave the code the possibility to evolve. But as the decisions made by code based on its interactions with the environment become harder and harder for its programmer or others to rationalise and explain, this standpoint becomes more questionable. This captures a quality of creativity that perhaps has got lost in modern definitions of the term that stress novelty and the creation of value. These have their origins in self-help books written by the advertising executive Alex Osborn in the 1940s that aimed to realise creativity in individuals and so help them make money. Before this commercial attitude took over, creative activity was more about capturing our attempts to understand being in the world. Machine learning taps into this earlier take on creativity, in that its output is an original expression of a machine’s interactions with an emerging digital world. But something fundamental is still missing: intentionality. What is driving the AI to blurt out a creative product? A human. Someone presses the print button, a person often chooses which algorithmic outputs to put in front of another human being. In that sense, AI doesn’t display

the same intentionality in creativity as humans do. Can it ever? To answer that question, we must first ask what drives our own urge for artistic creation. And for me, that is bound up with the hard problem of consciousness: the difficulty of explaining the true nature of felt experience in ourselves and other sentient beings. Because it is impossible to get inside each other’s heads to experience what another person’s pain or ecstasy feels like, we create works of art as a kind of functional MRI scan to reveal our conscious world and share it with others. A novel or a musical composition or a painting is our best way to help gain access to another person’s mind. I can’t prove it, but I wonder whether true creativity and consciousness emerged at the same time in the human species. Perhaps only when we had consciousness did we start to wonder what was going on in the minds of others and want to share our own internal worlds – and begin to express ourselves creatively. If so, I think that true creativity in machines will only happen when they have a conscious world they want to convey to us. I suspect that moment will be reached, but probably only in the distant future. When it does arrive, however, machine consciousness is likely to be very different from our own. And it will be AIs’ acts of artistic creativity that will be the best vehicle for accessing the strange world of what it is to be a conscious machine. ❚ Watch a video interview with Marcus du Sautoy on AI creativity at newscientist.com/marcusinterview 11 May 2019 | New Scientist | 41

Features

Earth’s deep, dark secret =RPELHPLFUREHVĸRXULVKLQJIDUEHQHDWKWKHVXUIDFH FRXOGUHYHDOOLIHóVVWUDQJHRULJLQVVD\VGraham Lawton “

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HE first ten million years were the worst,” said Marvin, “and the second ten million years, they were the worst too. The third ten million years I didn’t enjoy at all. After that I went into a bit of a decline.” Poor old Marvin the Paranoid Android, left to wait for eternity in a car park at the Restaurant at the End of the Universe. But if the ordeal of this Douglas Adams character seems trying, consider the real-life fate of microorganisms discovered buried in sediment under the South Pacific in 2010. They had been there for around 100 million years. And they were still alive – barely. Their metabolisms had slowed to a crawl and they were using what little energy they had just to stay in the game. But alive they were. “They’re definitely breathing!” says Steven D’Hondt at the University of Rhode Island, who discovered them. The presence of ancient, zombie microbes entombed deep under Earth’s surface may seem surprising, but D’Hondt and his crew would have been more surprised not to find them. Wherever we drill into the planet, we find life. And while some is zombie-like, most is not. Life underground is rich, dynamic and deeply strange. What it teaches us has important implications for our concept of life itself, not just here on Earth, but on other planets too. For centuries, nobody thought that Earth’s crust was anything other than inanimate rock. The first hint to the contrary came in 1926, when US geologists extracted water from oil wells nearly 600 metres down and discovered bacteria swimming inside. If true, this would have been a remarkable discovery. Instead, it was widely dismissed as contamination. Attitudes towards deep life changed in 1977 when scientists aboard a US research submersible discovered hydrothermal vents

42 | New Scientist | 11 May 2019

on the floor of the Pacific Ocean. These “black smokers” were teeming with life fuelled by chemical energy from way underground. In 1992, inspired by these discoveries, boundary-breaking astrophysicist Thomas Gold published a paper called “The deep, hot biosphere”. He reasoned that similar energy sources wouldn’t be confined to vents, and speculated that Earth’s subsurface was teeming with microbial life living in the pores between rocks. The size of this biosphere might equal that of surface life, he said, and such organisms “may be widespread among the planetary bodies of our solar system”. A quarter of a century on, Gold’s speculations have been vindicated – at least on Earth. Drilling projects on land and at sea, expeditions to deep mines and surveys of ocean vents have confirmed the existence of a deep, hot biosphere of amazing size and diversity. “There’s an entire living realm beneath our feet,” says Robert Hazen, executive director of the Deep Carbon Observatory at the Carnegie Institution for Science in Washington DC. “A vast biosphere that’s invisible, not just because it’s microscopic, but because it’s literally in solid rock.” “It’s massive,” says Cara Magnabosco, a deep-life researcher at the Flatiron Institute in New York. She recently compiled data from hundreds of studies around the world to come up with an estimate of the size of the deep biosphere. Her conclusions are staggering: its volume is twice that of all the oceans combined, about 2 billion cubic kilometres, and it contains an estimated 1030 microbial cells. That is 70 per cent of all microbial life on Earth. “The subsurface biosphere is the largest biosphere on the planet and holds the majority of microbial life,” says Magnabosco. Unsurprisingly given its inaccessible location, the deep biosphere remains largely

Graham LVDVWDIIZULWHUDQG FROXPQLVWDWNew Scientist VSHFLDOLVLQJLQELRGLYHUVLW\ HQYLURQPHQWDQGELRPHGLFLQH )ROORZKLP#*UDKDP/DZWRQ

“Having drilled more than 4 kilometres into the crust under land, scientists have still never hit sterile rock”

unknown. “We’re getting snapshots, but compared to pretty much any other environment on Earth, we have sampled very little because so much effort has to go into creating a borehole, or drilling a deep drill core out in the ocean or looking at a mine,” says Karen Lloyd, a geomicrobiologist at the University of Tennessee, Knoxville. However, with improvements in drilling technology and DNA sequencing, she and others are gradually revealing a biosphere some call the “subterranean Galapagos”. Almost all deep life is simple, single-celled organisms, mostly bacteria and archaea plus a few microeukaryotes and fungi, living in cracks or pores in the rock – although there are a few multicellular animals too. Most have yet to be formally identified. “We call it ‘dark microbial matter’,” says Tullis Onstott, a geomicrobiologist at Princeton University. As far as we know, this biosphere extends around the world, under land and oceans alike. It starts a few metres below the surface and goes way, way down.

PETER GREENWOOD

The limits of life Having drilled more than 4 kilometres into the crust under land and 2.5 kilometres into the seabed, scientists have still never hit sterile rock. The deepest living biological samples in Magnabosco’s survey were taken from about 5 kilometres down at drill sites in China and Sweden. Everybody agrees that there has to be a cut-off point somewhere, but where it is remains unknown. “At some point, there should be temperatures, and possibly also pressures, that limit life because molecules fall apart,” says Lloyd. The main limiting factor appears to be heat. On average, the temperature of continental crust rises by about 25°C for every kilometre you go down. In oceanic crust, the gradient is less steep, about 15°C per kilometre. That would quickly overwhelm the heat tolerance of multicellular organisms, but microbes are made of sterner stuff. Many extremophiles can tough out temperatures well in excess of 100°C, and where high pressure prevents water from boiling, they can go even higher. The current record holder is the archaeon Methanopyrus kandleri, which lives at 110°C in hydrothermal vents in the Gulf of California and has been cultured at 122°C in the lab. The record in the wild is set by another species of vent archaeon, Geogemma barossii, which grows and replicates at 121°C. It is conceivable that deep in the crust, at extreme pressures, microorganisms > 11 May 2019 | New Scientist | 43

survive at even greater temperatures, says Hazen, maybe as high as 150°C. If so, that would push the theoretical threshold to about 6 kilometres deep on land and 10 kilometres beneath the ocean, perhaps even more. “If you have places with relatively cool rock, you might be able to go down deeper than 10 kilometres and still have temperatures within that limit,” says Hazen. In some thick, ancient crust, 122°C isn’t reached until 23 kilometres down, according to Magnabosco. That pushes the envelope even further, assuming that the microbes can take the pressure. Finding out for certain, though, is way beyond the reach of current drilling technology. The deepest hole ever sunk is the Kola Superdeep Borehole in Russia, near the border with Norway. Begun in 1970, its scientists aimed to reach 15 kilometres. After grinding away for nearly 20 years, they

were forced to stop short, at 12,262 metres, scuppered by higher-than-expected temperatures in the borehole. Temperature and pressure are big challenges, but they are far from the only ones you face if you live deep underground.

Rock eaters Another challenge is energy. The two main lifestyles on the surface – photosynthesis and heterotrophy, aka eating food – rely on the presence of light and either organic matter or oxygen. Far below the surface, these are rarely on offer. Instead, microorganisms have to open a box of metabolic tricks. “There are some really novel biochemistries,” says Hazen. In some places, there is enough organic matter – often fossilised hydrocarbons – to support communities of heterotrophic microbes. Most of these are anaerobic,

replacing oxygen with nitrate, sulphate or metal ions and generating myriad waste products for other microbes to feast on. But by far the most common deep lifestyle is autotrophy, which means making your own food. Under the earth, microbes use the rock itself as a source of energy. Under intense heat and pressure, chemical processes generate energy-rich inorganic molecules that microbes can break down to produce energy. Collectively, these organisms are known as chemolithotrophs, which literally means “chemical rock eaters”. Almost any inorganic compound can be used as a source of energy, but the most important is hydrogen. This is produced from a range of reactions between rocks and water, as well as from the splitting of water by Earth’s background radiation and from silicate rocks being crushed by tectonic activity. Hydrogen-eaters also produce waste

The greatest The underground biosphere is pretty amazing (see main story). Here are some of its record-breaking inhabitants

Hottest

Biggest

Oldest

Deepest

Most exclusive

Until recently, the record holder was an archaeon or single-celled microorganism called Pyrolobus fumarii, discovered on the wall of a hydrothermal “black smoker” in the midAtlantic ridge in 1996. It grows optimally at 106°C and can survive at 113°C. It has since been bested by Geogemma barossii, a methane-producing archaeon discovered in a hydrothermal vent on the Juan de Fuca ridge in the Pacific Ocean. It can grow and replicate at 121°C.

In 2011, a team reported finding a nematode worm 1.3 kilometres below ground in a South African gold mine. It was later confirmed that this was indeed its natural habitat, where it fed on microorganisms. Half a millimetre long, Halicephalobus mephisto (pictured on opposite page) is the monster of the subsurface world. “It exists at the upper temperature limit for multicellular organisms,” says Tullis Onstott, part of the team that made the find.

In 2010, the scientific drilling ship JOIDES Resolution, used by the International Ocean Discovery Program, bored deep into sediments under the South Pacific gyre. In its samples were microbes trapped in sediment that was at least 100 million years old. Nobody is entirely sure how old the organisms are, but analysis suggests they are probably several million years old. Scraping by on increasingly scarce scraps of organic matter buried alongside them, they can do little more than hunker down. “They’re living lives of quiet desperation,” says Steven D’Hondt at the University of Rhode Island, who discovered them.

The deepest signs of life seen so far come from about 7 kilometres underground, from the Kola Superdeep Borehole in Russia. But the project wasn’t explicitly about biology and the discovery isn’t considered watertight. The deepest organisms to be properly characterised are a mixture of bacteria and archaea from a 5-kilometre borehole in China. Microbes have also been discovered 2.5 kilometres under the sea floor. “Maybe that doesn’t sound that impressive as a distance because we’re used to thinking of lateral distances, but when you’re drilling down a deep core, that is an impressive feat,” says Karen Lloyd, a microbiologist at the University of Tennessee, Knoxville.

Around 2.8 kilometres below the surface in South Africa’s Mponeng gold mine is one of the most peculiar ecosystems ever discovered. More than 99.9 per cent of the organisms in it are a single species, the bacterium Desulforudis audaxviator, making it the world’s only known one-species ecosystem.

44 | New Scientist | 11 May 2019

The nematode worm Halicephalobus mephisto is the predatory monster of the subsurface world

GAËTAN BORGONIE, ELI, BELGIUM

products that other microbes can consume. The subsurface ecosystem is thus organised into complex food chains, with primary producers at the bottom and networks of consumers feeding off their waste, and that of others. There are also apex predators, sometimes microbe-eating multicellular worms (see “The greatest”, below left). Nonetheless, it is an environment where the pace of life is slow. “In some places, life is surviving on less energy than we thought possible,” says Lloyd. “I think this changes our conception of how biology works, to be more in step with geological rhythms and processes, not the fast timescales that the surface world seems to function on.” And unlike ecosystems on the surface, this one is pristine. “This deep, subsurface world contains one of the very few ecosystems not yet pervasively altered by humans,” says D’Hondt. Given the metabolic creativity necessary to live under such conditions, many of the microbes are new to science. “There’s so much diversity,” says Lloyd. Some microbes belong to previously unknown groups right up to the phylum level: the taxonomic equivalent of discovering arthropods or molluscs. “We’re invariably surprised by what we find,” says Onstott. It is even possible that an entirely new domain of life is awaiting discovery, says Mitch Sogin of the Marine Biological Laboratory in Massachusetts, who is co-chair of the Deep Carbon Observatory’s Deep Life project. At present, biologists recognise just three domains – eukaryotes, bacteria and archaea. The discovery of the third of these in 1977 led to a major revision of the tree of life. A fourth would lead to a similar revolution. The diversity is also geographical. Just as on the surface, there are a handful of global species, but most are local. What lives where depends on the environment and the available energy sources. The biggest difference is between terrestrial and marine environments, says Magnabosco. Marine sediments all tend to be quite similar, maybe because they are saturated with water, whereas terrestrial ones depend on the type of rock. “There are many different rock types – granite, basalt, sandstones, clays – which all host very different microbial communities all doing different types of metabolism,” says Magnabosco. Some regions are rich and fecund, in a similar way to the Amazon. Others are deserts with just a few species. “In some ecosystems, there’s only a single kind of organism, which is kind of an alien concept,” says Hazen.

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Even more alien, these systems can be entirely separate from life as we know it. “Some of these deep microbial domains seem to have been isolated from the surface for very, very long periods of time,” says Hazen. This is perhaps the most jaw-dropping feature of deep life: in places, it is an entirely separate biosphere, running its own affairs with no connection whatsoever to life upstairs. One of the biggest implications is for our understanding of life’s origins. A tantalising possibility is that the isolated

“Life could have started underground and then spread upwards” subterranean ecosystems are descended from what biologists call a “second genesis”: an origin-of-life event separate from the one that gave rise to surface life. As yet, however, this doesn’t appear to be the case. All the microbes described so far use the same genetic code and biochemistry as life above ground, so by inference are descended from the same common ancestor, says Hazen. But what cannot be ruled out is that life got started underground and then spread up to the surface. “Reactions in the subsurface give rise to all the biomolecules that are necessary to support life,” says Lloyd. “As we learn more about the life that is down there, we are looking at it with an eye to determining whether it could be the origin of life too.” If so, that would have gigantic implications

for astrobiology, the study of life on other planets. Plenty of other bodies in the solar system and beyond have a subsurface not unlike Earth’s. If life got going underground – and has prospered there for the best part of 4 billion years – why not on Mars or other rocky planets, even ones with no sunlight? According to Onstott, there are regions on Mars where subsurface conditions are very similar to places on Earth with abundant deep life. And you don’t even have to posit an underground origin, he says. “On early Mars, surface conditions existed under which life could have emerged. It could quickly have migrated downwards into the subsurface.” For the foreseeable future, this remains speculation. NASA’s next mission, Mars 2020, plans to drill into the surface to search for signs of life, but not deep enough to reach a subsurface biosphere. We will have to wait for another mission – probably a crewed one – to get answers, says Onstott. But why stop at Mars? “Anywhere where there’s enough heat to generate a fluid environment at depth, you might find life,” says Onstott. “You could go to Mercury, to the southern polar regions of the moon or out to Pluto. There’s even talk of life on Ceres.” Even if deep life is confined to Earth, many new discoveries await us. The Deep Carbon Observatory has only been running for a decade and has merely scratched the subsurface. “I think it’s safe to say that the discoveries that have been made are mind-boggling and incredibly exciting,” says Hazen. “They open our eyes to a new kind of life.” ❚ 11 May 2019 | New Scientist | 45

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University of Alabama at Birmingham Radiation Oncologists The Department of Radiation Oncology at the University of Alabama at Birmingham is currently recruiting for Radiation Oncologists at the level of Assistant/Associate Professor. We are interested in clinical trialists or physician scientists and experience with proton therapy would be helpful. We plan to open a proton facility in approximately one and a half years. These are tenure-earning positions. Applicants must be Board Certified or Board Eligible. Our goal is the delivery of technically advanced radiotherapy in combination with new agents developed in the laboratory to enhance cancer care and provide treatment in a pleasing and educational environment. Current recruiting activities are focused on individuals with an interest in translational and clinical research in addition to patient care. Laboratory resources are available for qualified candidates. We have an exciting group of physician scientists who work in our very collaborative cancer center. New recruits will have the opportunity to interface with a collaborative group of clinical faculty and laboratory scientists. Potential candidates should possess an MD degree. Candidates should be Board Eligible or Board Certified in radiation oncology. For more information please email your questions to Dr. James A. Bonner at [email protected] Interested applicants please follow this link to apply: http://uab.peopleadmin.com/postings/3796 UAB is an Equal Opportunity/Affirmative Action Employer committed to fostering a diverse, equitable and family-friendly environment in which all faculty and staff can excel and achieve work/life balance irrespective of, race, national origin, age, genetic or family medical history, gender, faith, gender identity and expression as well as sexual orientation. UAB also encourages applications from individuals with disabilities and veterans. A pre-employment background check investigation is performed on candidates selected for employment. In addition, physicians and other clinical faculty candidates who will be employed by the University of Alabama Health Services Foundation (UAHSF) or other UAB Medicine entities, must successfully complete a pre-employment drug and nicotine screen to be hired.

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Postdoctoral Research Fellowship Position Dr. Holoshitz’ laboratory seeks applications from talented candidates for a post-doctoral position in the Departments of Internal Medicine at the University of Michigan School of Medicine. The individual will carry out funded research projects related to new mechanism of MHC-disease association. Approaches include transcriptomics, immunology, cell biology, proteomics, biochemistry, mouse models. The selected FDQGLGDWHVZLOOKDYHRSSRUWXQLW\WRGHYHORSVSHFL¿FSURMHFWVDFTXLUHQHZVNLOOV participate in seminars and other academic activities, including presenting at national conferences.

Representative publications: Arthritis Rheumatol. 67:2061-70, 2015 Arthritis Res Ther. 18:161, 2016 Rheumatic and Musculoskeletal Dis. 2 (2), 2016 Proc. Natl. Acad. Sci. (USA) 15:4755, 2018

4XDOL¿FDWLRQV ‡3K'DQGRU0'LQPROHFXODUELRORJ\FHOOELRORJ\LPPXQRORJ\JHQHWLFVRUUHODWHG¿HOG • Working knowledge of immunology, arthritis models, signal transduction, transcriptomics and protein chemistry • Ability to work collaboratively with individuals from different backgrounds • Excellent verbal and written communication skills

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The back pages Puzzles Cryptic crossword, a quiz and a railway riddle p52

Feedback Marvel v phobias, and ZooTube: the week in weirdness p53

What does… Liana Finck? A cartoonist’s take on the world p53

Almost the last word Space junk and insect feelings: your queries answered p54

Me and my telescope Mars geologist Tanya Harrison answers our questions p56

How to be a maker Week 2

Let there be electric light

Hannah is a science writer and maker based in London

What you need 3 crocodile-clip wires 9V battery LEDs Assorted resistors Asparagus

For next week Piezo buzzer Toaster Tinfoil Cardboard Chopsticks

Next in the series 1 Introduction 2 Electric candle 3 Toast notifier Upgrade your circuit with switches 4 Rate-my-stay device 5 Propeller car 6 Magic eight ball 7 Theremin 8 Sound-sensitive disco ball 9 Rubbish sweeper 10 Biscuit bot

THE candle. It is a simple technology, and a good one. The electronic version is also simple to make, and is a great introduction to the concept of circuits – the cornerstone of many maker projects and core knowledge for the budding robot-builder. Circuits are always complete loops that run from one terminal of a power source, such as a battery, to the other, going through some components on the way. The components are essential: connecting the terminals of the battery directly together will create a short circuit, and that’s bad news. The full energy of the battery will flow back on itself unimpeded, leading to heat and damage. A component – an LED, say – tempers the flow by putting some of that energy to use. A couple of things to note about these little lights before you get going. First, they are polarised, which means current will only flow through them in one direction and so you have to attach them the right way round. Take a look at an LED. You will see that one leg is longer than the other. Just remember that the longer leg is positive. The second point to remember is that LEDs are easy to fry. They tend to operate between about 1.5 and 3.5 volts (it will say on the packet), so connecting one to a 9V battery can be a death sentence. To prevent this, add a resistor, which will dissipate some power and reduce current flow, bringing it down to a level where the LED is happy. To pick which resistor to go for, check what current the LED

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This week, Hannah Joshua reveals the secrets of the circuit – and how to test the conducting properties of asparagus

Make online Projects and extra pictures will be posted each week at newscientist.com/maker Email: [email protected]

will take and either use Ohm’s law (resistance = voltage ÷ current) to work out the right resistor to use, or cheat and start with 300 ohms. When you build your circuit, don’t touch any naked metal or you will get a shock. The small currents in this sort of circuit mean becoming part of it isn’t life-threatening, but it isn’t that comfortable. Take it from someone who knows. Start with your 9V battery and connect its positive terminal (+ or red) to the resistor using a crocodile clip wire. Connect the other side of the resistor to the positive leg of the LED (green wire in the photo above). Attach the

other leg of the LED to the battery’s negative (black) terminal. That’s it – you have made an electronic candle. Bask in the literal glow of success. Stick it on a bulldog clip and you can use it as a tiny reading light. Experiment with different resistors. Higher values will make the LED dimmer, while lower values will make it brighter, until it burns out. Bonus game: now you can play “Will it Conduct?” by adding anything from asparagus to jewellery to your circuit in place of one of the wires and see whether the LED lights up. Let me know what you find. ❚ 11 May 2019 | New Scientist | 51

The back pages Puzzles Quick quiz #02

Puzzle set by Matt Scroggs

1 What is the name given to an irrational number ZULWWHQIRUH[DPSOHDVĭ to express its exact value without all its digits?

#02 Getting past the freight train

2 In what southern German city was Albert Einstein born? 3 Known also as aqua fortis, what acid was used in the original acid test, and to do what? 4 Described as a “wildlife wonder of the world”, the 3-hectare Bass Rock off the north-east coast of the UK is home to the world’s largest colony of which seabird, numbering some 150,000?

Down 1 Fashion mass communication device (5) 2 Operated recklessly and naively at first (3) 3 Very backward sound of reaping hook or hammer, say (7) 4 Restive banter excited spineless creatures (13) 5 They help to see traffic markers (5) 6 Rare earth element has city ordering manhunt (9) 7 Preserve primates for starters (7)

15 Number inside, for example, the queen (7) 17 Time to approach first icy rock (5) 19 Carbon-neutral enclosure of iron or stone, say (3) 20 Halo seen on insect and male cat (9) 22 Surrender produce (5) 23 Unmatched quality in dispatch put on hold (7)

11 Maybe platypus adapted meme, or not (9) 13 What’s given up online? Look closely around four acres (7) 14 Supporters replace leader with hot computer experts (7) 16 Dash out of country might make you sweat (5) 18 Muscular tiger has tail removed by journalist (5) 21 Hail headless insects! (3)

Answers and the next quick crossword next week.

52 | New Scientist | 11 May 2019

Answers below

Quick Crossword #30 Answers Across 1 STARGATE, 5 PSYCHE, 10 L WAVE, 11 MACINTOSH, 12 TECHNICAL, 13 NADIR, 14 PREAMP, 15 AUROCHS, 18 QUANTUM, 20 LEAKEY, 22 A-TYPE, 24 RAIL FENCE, 25 OESTROGEN, 26 U-BOAT, 27 STIGMA, 28 AZOTEMIA Down 1 SOLUTE, 2 ARAUCARIA, 3 GREEN-TAO THEOREM, 4 TIME COP, 6 SAN ANDREAS FAULT, 7 CLOUD, 8 ETHERISE, 9 SCILLA, 16 CLEAN ROOM, 17 SQUAMOUS, 19 MIRAGE, 20 LEIBNIZ 21 BERTHA, 23 YOSHI

Quick quiz #02 Answers 1 A surd 2 Ulm 3 Nitric acid, to distinguish gold from other metals 4 The northern gannet. Its formal name, Morus bassanus, derives from the rock 5 Mosaic

Across 1 Ruin trick by setter and radio presenter (7) 5 Bit of broccoli causing child’s complaint (5) 8 Ancient human’s shelter is nothing next to mobile home (9) 9 Grandmother’s bread (3) 10 Copy note on audio device (5) 12 Elevated trendy fruit (7) 13 Singer, retired footballer and hotel workers seen by drunk? (4,9)

5 Developed by the US National Center for Supercomputing Applications and released in 1993, what was the first widely available graphical web browser called?

A very long passenger train is heading along a single track railway behind a freight train composed of a locomotive and three freight trucks. They are approaching a station where the freight train is due to unload. To keep to its timetable, the passenger train needs to leave before the freight train will have had time to unload. At the station, there is a siding that either train could drive into. The siding is large enough to hold a locomotive and one freight truck, or two freight trucks. Both trains have couplings at the front that allow them to push and pull trucks. How can the passenger train get past the freight train so that both can continue on their journey? Answer next week

PASSENGER

Cryptic crossword #06 set by Wingding

#01 The book of numbers Solution Last week, we asked you for the second and second to last numbers in a book listing all the whole numbers from zero to infinity in alphabetical order. The second number is 8,000,000,000 (eight billion). The second last is 2,000,000,002,222 (two trillion two thousand two hundred and twenty two).

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The back pages Feedback Superfearos Scared of spiders? Afraid of ants? New research by a team in Israel suggests that watching movies showing them in a good light could help. Just a 7-second excerpt from the Marvel superhero movies Spider-Man and Ant-Man reduced symptoms of arachnophobia and myrmecophobia by 20 per cent. Feedback shudders slightly, but achieves distraction by wondering what other phobias might be treated by a suitably expanded Marvel universe. Might agoraphobia, for example, be alleviated by the release of Open Spaces Woman? The eponymous hero, a vast swathe of beachfront granted sentience in a freak lightning storm, roams the land, spreading righteousness and wet sand wherever she goes. Gaze in awe at her rippling dunes and cape of microplastic-infused sludge, and swoon as she delivers her notorious catchphrase: “ !” Claustrophobes, too, will await with bated breath the outcome of her titanic battles with her sworn enemy, Captain Confinement. A good reason not to leave the house.

Fitting image Face-recognition systems that unlock your computer are certainly convenient, but a Twitter post by Matt Carthy, an Irish member of the European parliament, offers a cautionary tale. “So, I was wondering why the battery on my laptop was running down every time I left it at home,” he wrote. “Turns out the kids have been using my election leaflets to get through the facial recognition lock… I’m not sure whether to be proud by the wit or concerned by the sneakiness?”

Sasquatch hopscotch At last! A story for fans of the fearsome, cold-loving, humanoid white walkers from Game of Thrones that they can consume without fear of spoilers. An Indian army Twitter account reports that a patrol in the Himalayas has found

evidence of the Yeti, the white walker lookalike and big furry hominid best known for almost certainly not existing. Shared with more than 6 million followers, the evidence consists of enormous footprints proceeding across a snowy slope in an uncanny single line. If the abominable snowman is in fact responsible, he has either taken to hopping or has adopted a swivel-hipped swagger to make Mick Jagger jealous.

What does Liana Finck?

ZooTube A recent viral video showed a chimpanzee browsing Instagram on a smartphone, swiping and tapping with the assured air of the most screen-addicted human. Darn you, Mark Zuckerberg! Could your addictive social media content be tapping into primal instincts so deep that we share them with cousins from whom we diverged millions of years ago? What was that? Sorry, wasn’t listening, something on my phone. Actually, it is a list of recommendations of accounts to follow on top non-human-primate social network Chimpstagram: ❚ For exciting ideas about what to eat, try @junglegourmet’s mouthwatering photos of delicious meals, such as avocado with ants, banana puree and monkey carpaccio. ❚ Follow the literary world’s favourite Pan troglodytes-with-atypewriter as she furiously tries to produce the complete works of Shakespeare. Go @shakeschimp, you can do it – only the complete works of Shakespeare to go. ❚ @realDonaldChimp uses the platform to consolidate power by intimidating his rivals. The videos of his violent outbursts have a strangely addictive quality. ❚ The short, snappy videos from @toolmaster teach you incredible lifehacks that will save you time and impress your friends. Learn the best technique to fish for termites, crack open nuts with rocks or prise open a beehive. ❚ Chimpstagram’s number one influencer @PetraPan is the go-to

ape for grooming tips, heartfelt monologues and stunning selfies in exotic locations. Best of all are her hilarious prank videos, like when she threw her faeces at @realDonaldChimp. ❚ Of course, the best thing on Chimpstagram are the accounts devoted to adorable pet humans, like @thehairlessape. Watch them use phones just like us.

Not cricket Nature enthusiasts can be forgiven for getting excited when they encounter a surprising species in the wild, but it always pays to be methodical before claiming a new discovery. Reader Paul Beckett thought he had discovered a rare mole cricket at a new UK location, and sent recordings of its characteristic chirruping to the Natural History Museum. “However, going back to the location to investigate, it was found

to be the buzzing of a security tag ripped from a luxury good that had no doubt been robbed a few days earlier,” Paul writes. “I now have to call off the experts and embarrass myself with the truth.”

Right on the money Finally, a brief relapse into the world of nominative determinism. Reader Helen D. Haller writes in about the assistant director of the Erie Bird Observatory in Pennsylvania, Mary Birdsong. Meanwhile, a recent episode of The Art and Science of Blending on BBC Radio 4, featured an interview with the long-time master blender at whisky producer Johnnie Walker, a Dr Jim Beveridge. That particular example was sent in by a regular reader, Barry Cash, who berates us for not explaining how a person can have nominative determinism thrust upon them. “Why do I never have any?” he asks plaintively. ❚

Want to get in touch? Send your stories to New Scientist, 25 Bedford Street, London WC2E 9ES or you can email us at [email protected] 11 May 2019 | New Scientist | 53

The back pages Almost the last word Eider ducks fly in sub-zero conditions, but why don't their eyeballs freeze?

Space reflectors

Richard Lucas Camberley, Surrey, UK Since 1957, more than 5000 launches have led to in excess of 22,000 tracked objects in orbit around Earth. But only a minority are working satellites. The rest, including satellites no longer serving a useful purpose, are debris. Many derelict craft have broken up, generating an estimated 900,000 pieces between 1 centimetre and 10 centimetres across, and a staggering 128 million between 1 millimetre and 1 centimetre in size. All of these will absorb or reflect solar radiation to an extent, depending on colour and reflectivity. Travelling at speeds in the order of tens of thousands of kilometres per hour, even these tiny bits of junk present a danger to satellites. The International Space Station was damaged in August 2018, though it isn’t yet clear whether this was caused by flying debris. But despite the large amount of junk, the total number of pieces in orbit is relatively small compared with the area of the planet that is exposed to solar radiation. Also, since all of these bits are in orbit around the planet, less than half of them will be between the sun and Earth at any time. So while space junk will have an impact on incoming solar energy, that effect is vanishingly small. Eric Kvaalen Les Essarts-le-Roi, France It has a tiny effect. Although it isn’t clear in which direction the light is reflected, it is such a small amount as to be totally negligible. One gets the impression from some articles that there is so much junk up there that it is like a swarm of gnats, but, in fact, the total mass – and total cross-sectional area – is small. 54 | New Scientist | 11 May 2019

MARK CARWARDINE/NATUREPL.COM

Does the space junk orbiting Earth have any effect on the amount of solar energy reaching the surface of our planet, either by absorbing or reflecting it?

This week’s questions It is a windy -20°C outside and I just saw a flock of ducks fly over. How do the birds stop their eyeballs freezing? Stan Stancliffe Calgary, Alberta, Canada What is dust? What is it made of, and is it bad for human health? Emilie Smith (age 15) Birkenhead, Wirral, UK

Mike Follows Sutton Coldfield, West Midlands, UK Satellites vary greatly in size, but if we assume that the average cross section is 5 square metres, this means that on Earth they could all be parked in a field measuring about 0.025 square kilometres. So in space, they would intercept only a tiny fraction of 1 per cent of the sunlight that is heading for the planet, provided they are between the sun and Earth, of course. In the section of space out to 2000 kilometres above Earth’s surface, there is less than one piece of space debris larger than 1 cubic millimetre for every 10,000 cubic kilometres of space. Though this equates to a huge number of pieces of debris, only around 34,000 exceed 10 centimetres across. The effect of space debris on solar energy reaching the planet would increase if there were a chain reaction of collisions, in which one piece of debris hit a satellite, breaking it up into thousands of pieces that hit other satellites and then did the same again. Yet even if this happened, it wouldn’t have a significant impact on the amount of sunlight reaching us.

Feeling fly Do insects have emotions in the same way humans and mammals do? For example, would a fly feel sad if it saw its brother die?

Jonathan Wallace Newcastle upon Tyne, UK There is nothing in the behaviour of insects that suggests any kind of emotional life that resembles that of humans. Insects have very simple brains compared with mammals, and much of their behaviour is produced by simple reflex responses to stimuli. The second question assumes that a fly would recognise its brother, which is doubtful. There is plenty of evidence that many insects have little or no sense of family bond. The female praying mantis, for example, famously cannibalises her mate during the act of copulation. The orange tip butterfly normally lays just one egg per plant, but if she lays two

by chance, then one of the resulting caterpillars will probably eat the other, sibling or not. The social insects do, of course, cooperate closely with their family members and demonstrate high levels of self-sacrifice in the interest of their colony. But there is no evidence that this behaviour is regulated through emotions. Stefan Badham Portsmouth, Hampshire, UK Anyone who has ever disturbed a wasp or ant nest will certainly know that insects feel anger, probably triggered by fear. They obviously procreate, and are extremely social with their own species, though this is probably born more out of a mechanical precondition than sexual arousal or a need for company. So, while insects evidently possess base emotions, the question of whether they feel empathy, sympathy, love and grief is another matter. Although a human is capable of feeling and demonstrating kindness to an insect, it remains unknown if such emotions are ever reciprocated. Venkata Sri Sai Vellore, Tamil Nadu, India In his book The Expression of the Emotions in Man and Animals, Charles Darwin suggested that animal emotions include anger, terror, jealousy and love. Recent research has found that insects have the cognitive and physiological building blocks that might give rise to complex phenomena such as emotion. For example, bees that were given rewards when they reached a certain site became more optimistic than other bees (8 October 2016, p 9).

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The back pages Me and my telescope

Tanya Harrison is a planetary geologist and director of research for Arizona State University’s NewSpace Initiative. She likes everything about Mars – except its nickname Do you have a telescope? Not at the moment, but I owned one as a child and about 10 years ago. Maybe someday, if I stop moving around so much, I will pick one up again!

As a child, what did you want to do when you grew up? I wanted to work on something related to space ever since I was 5 years old, thanks to Star Trek. When Mars Pathfinder landed in 1997, my attention turned to Mars specifically.

Explain what you do in one easy paragraph. I am a planetary geologist, studying features on Mars that can tell us about its past. I have worked in mission operations for the Opportunity and Curiosity rovers, and the Mars Reconnaissance Orbiter. I also create partnerships between the university and commercial space firms.

Sum up your life in a one-sentence elevator pitch… I’m a professional Martian working on rocks and robots on the Red Planet.

What do you love most about what you do? I love studying cool images from Mars to try and unlock its secrets. You never know what you might find. It never gets old.

What’s the most exciting thing you are working on right now? I am working on a project to improve food and the experience of eating in space. It is different from anything I’ve done before, but it combines two of my loves: space and food.

Were you good at science at school? Yes. I was definitely a stereotypical science geek, but I also really owned it, so rather than being teased, everyone kind of respected it.

If you could send a message back to yourself as a kid, what would you say? Even though you have the chance to skip second year algebra, don’t do it. It will come back to haunt you in calculus class at college. 56 | New Scientist | 11 May 2019

What’s the best piece of advice anyone ever gave you? A friend once said: “Remember, you know more about the specific thing that you are talking about than anyone else in the room. Be confident in that.” That really helped me get over my fear of public speaking.

If you could have a long conversation with any scientist, living or dead, who would it be? Stephen Hawking was a big inspiration to me as a teen after I had been diagnosed with ankylosing spondylitis because he was the only scientist I knew of with a physical disability. I would love to just sit with him at a dark sky site, stare up at the stars, and speculate about the universe.

What’s the best thing you’ve read or seen in the past 12 months? The Apollo 11 IMAX film, hands down. It was a powerful reminder that humans are capable of incredible things, especially when given a focused goal and the finances to back it up.

Do you have a weird hobby and, if so, please will you tell us about it? I have a love of public transit systems, particularly the Toronto subway. I like to ride subways to see the various stations. There’s something peaceful about zoning out while riding the subway.

How useful will your skills be after the apocalypse? Unless we are living on Mars, probably not very useful.

OK, one last thing: tell us something that will blow our minds… Calling Mars the Red Planet is a bit of a misnomer. Under the thin veneer of reddish, rusty dust, Mars is actually more of a grey colour, like the moon. ] PORTRAIT: ABIGAIL WEIBEL, IMAGE: NORMAN POGSON/ALAMY STOCK PHOTO

“Calling Mars the Red Planet is a misnomer. Under the veneer, it is actually more of a grey colour”