New Scientist Sept 21 2019

SAVE 15% USE CODE FINAL15

JOIN US AT THE WORLD’S GREATEST SCIENCE FESTIVAL 10 -13 October | ExCel London

BIG THINKERS

OLA ROSLING • CAROLINE CRIADO-PEREZ • LEE BERGER • ALICE ROBERTS • AVI LOEB

GELONG THUBTEN AND ASH RANPURA • MEGAN ROSSI • PAUL DAVIES • MAGGIE ADERIN-POCOCK MARTIN REES • MARCUS DU SAUTOY • LIZ BONNIN • ROBERT PLOMIN • JO DUNKLEY • VLATKO VEDRAL JOANNA BRYSON • MARK MASLIN • JACQUELINE MCGLADE • GEOFF SIMM • GINA RIPPON • AL WORDEN

BIG IDEAS AND BIG ISSUES

IS MARS HABITABLE? • ARE WE ALONE? • WHAT HAVE INSECTS DONE FOR US? CANNABIS AND MENTAL HEALTH • THE FUTURE OF HEALTHCARE • THE FUTURE OF ENERGY HOW CLIMATE CHANGE IS AFFECTING AIR TRAVEL • IS GAMING BAD FOR US?

WEIGHING FORESTS FROM SPACE • IN PURSUIT OF ONLINE PRIVACY • WHAT’S THE POINT OF DADS? FIXING THE PLASTIC WASTE PROBLEM • AIR QUALITY • THE TRUTH ABOUT DIETS

FOR CURIOUS MINDS

BOBBY SEAGULL • DOCK A SOYUZ SPACECRAFT • LEVITATING WITH SOUND

CARNIVOROUS PLANTS • SUPERHUMANS • MARS ROVER • RELICS FROM THE MARY ROSE DINOSAURS OF BRITAIN • WHAT WE CAN LEARN FROM ANCIENT TECHNOLOGIES • OUMUAMUA SCIENCE COMEDY QUIZ • AFTER-DARK DISCO • HOW EARTH MADE US • CONSERVATION DRONES WHY DO SMART PEOPLE DO STUPID THINGS? • GUT HEALTH • AGEING • THE SCIENCE OF FATBERGS

Only three weeks to go! Visit newscientistlive.com and use code FINAL15 *Valid on Standard and Friday Night Late tickets

SPONSORS AND PARTNERS

SPEAKING CHIMP

Do we share an ancestral sign language with our ape cousins?

VISITOR FROM DEEP SPACE

Second-ever interstellar comet is heading our way

RINGING BLACK HOLES Einstein proved right (yet again)

WEEKLY 21 September 2019 No3248 Australia $9.50 (Inc. GST) New Zealand NZ$9.50 (Inc. GST) Print Post Approved 100007877

T H E T R U E N AT U R E O F

CONSCIOUSNESS W E ’ R E F I N A L LY C R AC K I N G T H E G R E AT E S T M Y S T E RY O F YOU

‘WE ARE ALL IRRATIONAL’

Richard Dawkins on God, evolution and Islamophobia

3 8

PLUS FIRST WATERY EXOPLANET FOUND / CRABS THAT GROWL / OUR VANISHING GLACIERS / INFINITE MATHS PROBLEM SOLVED News, ideas and innovation www.newscientist.com

9 771032 123104

Discovery Tours

USA

Cruise Hawaii with Richard Dawkins

Departing: 9 days from AU$15,199 22 October 2020

Join evolutionary biologist and highly regarded author Richard Dawkins on a boutique yacht Tour highlights include: k Evening seminars with Richard Dawkins k 7 nights aboard the Safari Explorer yacht - small enough to reach places that other vessels cannot k Explore Big Island’s living vocanic landscape and misty forests k Visit secluded bays and experience a large array of wildlife k Immersive exploration by boat, trekking,

k A thrilling night-time snorkelling adventure seeking giant manta rays k Enjoy the cultural treasure of a ‘pā‘ina feast and discover the history of this ancient homeland k A day in Kailua-Kona, where the slopes of the Hualalai volcano meet the ocean k Maui and Big Island plus the lesser visited islands of Molokai and Lanai

DAVID STOCK

snorkelling and private coach

To give guests the best possible experience there is a 2:1 guest-to-crew ratio and we only have 32 places available, so please get in touch early to ensure you don’t miss out.

To book or query email newscientist@steppestravel.com or phone UK +44 (0) 20 8108 9522 (Mon to Thu 9-5:30pm, Fri 9-5pm GMT)

newscientist.com/tours

In partnership with Steppes Travel

This week’s issue

On the cover

7 Speaking chimp Do we share an ancestral sign language with our ape cousins?

34 The true nature of consciousness We’re finally cracking the greatest mystery of you

3 weeks to go!

Discover why engineering is everywhere at our four-day festival of science. Find out more at newscientistlive.com

12 Visitor from deep space Second-ever interstellar comet is heading our way 6 Ringing black holes Einstein proved right (yet again)

38 ‘We are all irrational’ Richard Dawkins on God, evolution and Islamophobia

16 First watery exoplanet found 16 Crabs that growl 8 Our vanishing glaciers 13 Infinite maths problem solved Vol 243 No 3248 Cover image: Oska

News

Features

8 Our melting planet A special report on the world’s shrinking glaciers

34 Creating consciousness We have identified the four essential elements that make a conscious mind

Interview

12 Interstellar visitor A second object from a different solar system may be coming this way

38 Richard Dawkins’s mission The evolutionary biologist wants to break the cycle of superstition

15 Circadian rhythms Light therapy may relieve perinatal depression

42 An untold Amazon tragedy As huge parts of the rainforest burn, other areas are drowning

Views

The back pages

21 Comment Adults should join the climate strikes, argues Alice Bell

51 Stargazing at home Make a model of Earth’s orbit around the sun

22 The columnist Annalee Newitz on tech firms’ union confusion MARY TURNER, THE TIMES

52 Puzzles Cryptic crossword and a quick quiz

26 Letters There are several approaches to saving the Arctic Ocean 28 Aperture Rival mudskippers tussle for territory in Japan 30 Culture Inside the anti-science world of The Testaments

38 Richard Dawkins

“We really need to push the beauty of science”

53 Feedback Elongated eels and naming names: the week in weird 54 Almost the last word Lightning effects and biscuit/cake duality: readers respond 56 The Q&A xkcd creator Randall Munroe on the inventive use of science

21 September 2019 | New Scientist | 1

Discovery Tours

S OU T H A ME RI C A

Total Solar Eclipse 2020: Adventure in Argentina

Departing: 11 days from AU$4,589 (Early-bird price) 6 December 2020

A rare celestial event in one of the most spectacular locations on Earth.

Enjoy the magnificent show that is a total solar eclipse along with the stunning scenery of Patagonia and vibrant culture and sensory delights of Buenos Aires.

Renowned astronomer Dr John Mason will lead the eclipse experience at an exclusive viewing location as well as giving evening seminars on his eclipse-chasing adventures plus stargazing in the crystal-clear skies of Bariloche.

Tour highlights include:

k Seminars and expert-led eclipse

k Catamaran journey around

and astronomy experiences with Dr John Mason k Private viewing site in Piedra del Aguila for the eclipse k Bariloche National Park k Stunning tango dinner show

Nahuel Huapi Lake k Thorough exploration of Buenos Aires. European style with Latin spirit k The stunning natural landscapes and lakes of Patagonia k Gaucho horseman cultural day

In partnership with Intrepid Travel

To book or query email groupsuk@intrepidtravel.com Or phone UK +44 208 1089 641 (UK office 9am-5.30pm GMT) ABTA No.Y0766

newscientist.com/tours

The leader

The lightness of being

GETTY IMAGES

An engineering approach to consciousness promises help with an old question WHAT is it like to be a bat? Philosopher Thomas Nagel’s 1974 question has evolved to dominate our thinking on consciousness. Nagel’s point, simply put, is that even if we could fly, and navigate using sonar, we would never grasp what it feels like to be a bat. The argument has become the “hard problem” of consciousness, the intractability of explaining subjective experience.

Consciousness isn’t something you can measure or weigh; its ethereal quality is so fascinating as to verge on the mystical. Certainly it attracts plenty of mystical explanations.

So it is unsurprising that, despite decades of thought, we have been unable to explain how our brains create the conscious experience. Even if we might insist that the hard problem is illusory, or that consciousness is simply

Can we make a machine that does what a conscious human does?

the way information feels when processed in certain ways, we still need to understand how the illusion arises, and what kind of information in the brain gives rise to the feeling.

Philosophy alone isn’t enough.

This is where engineering comes in. To build something, you have to understand it precisely. Can we make a machine that does what a conscious being does, that constructs a self-image and uses it to produce descriptions of

the world? This week, we report on just such a project (see page 34).

The idea is that, just as any control device needs a model of the thing it is controlling, a brain needs a model of itself. The experience of a phantom limb – the feeling that an amputated arm, for example, is still present – comes about because the brain originally created an internal model of the arm to help control its movement. When the physical arm is gone, the model, the phantom, remains. The feeling of consciousness could be the phantom of the brain’s model of its own workings.

Although an engineering approach won’t allow us to grasp the essence of “batness”, it looks like a promising way to build artificial consciousness. Who knows, it might eventually explain the mystery of our own being. ❚

PUBLISHING & COMMERCIAL

MANAGEMENT

EDITORIAL

Display advertising Tel +44 (0)20 7611 1291 Email displayads@newscientist.com Commercial director Chris Martin Display sales manager Justin Viljoen Lynne Garcia, Bethany Stuart, Henry Vowden, (ANZ) Richard Holliman Recruitment advertising Tel +44 (0)20 7611 1204 Email nssales@newscientist.com Recruitment sales manager Mike Black Nicola Cubeddu, Viren Vadgama, (US) Jeanne Shapiro New Scientist Live Tel +44 (0)20 7611 1245 Email live@newscientist.com Events director Adrian Newton Creative director Valerie Jamieson Event manager Henry Gomm Sales director Jacqui McCarron Exhibition sales manager Rosie Bolam Marketing manager Katie Cappella Events team support manager Rose Garton Marketing executive Jessica Lazenby-Murphy Marketing Head of campaign marketing James Nicholson Poppy Lepora, Chloe Thompson Head of customer experience Emma Robinson Head of data analytics Tom Tiner Web development Maria Moreno Garrido, Tom McQuillan, Amardeep Sian

Chief executive Nina Wright Finance director Jenni Prince Chief technology officer Chris Corderoy Marketing director Jo Adams Human resources Shirley Spencer HR coordinator Serena Robinson Facilities manager Ricci Welch Executive assistant Lorraine Lodge Receptionist Alice Catling

Editor Emily Wilson Executive editor Richard Webb Creative director Craig Mackie News News editor Penny Sarchet Editors Jacob Aron, Timothy Revell Reporters (UK) Jessica Hamzelou, Michael Le Page, Donna Lu, Adam Vaughan, Clare Wilson (US) Leah Crane, Chelsea Whyte (Aus) Alice Klein, Ruby Prosser Scully Digital Digital editor Conrad Quilty-Harper Web team Lilian Anekwe, Anne Marie Conlon, David Stock, Sam Wong Features Head of features Catherine de Lange (parental leave) and Rowan Hooper Acting head of features Tiffany O’Callaghan Editors Gilead Amit, Julia Brown, Kate Douglas, Alison George, Joshua Howgego Feature writers Daniel Cossins, Graham Lawton Culture and Community Editors Liz Else, Mike Holderness, Simon Ings Subeditors Chief subeditor Eleanor Parsons Bethan Ackerley, Tom Campbell, Chris Simms, Jon White Design Art editor Kathryn Brazier Joe Hetzel, Dave Johnston, Ryan Wills Picture desk Picture editor Susan Banton Production Production manager Alan Blagrove Robin Burton, Melanie Green

© 2019 New Scientist Ltd, England.

Environment ISO 14001 Certification applies to Offset Alpine Printing

ISSN 1032-1233. New Scientist (Online) ISSN 2059 5387. New Scientist is published weekly by New Scientist Ltd, 25 Bedford Street, London, WC2E 9ES, UK. Registered as a newspaper. Printed in Australia by OVATO Print Pty Ltd, 31 Heathcote Road, Moorebank NSW 2170

Non-exec chair Bernard Gray Senior non-exec director Louise Rogers

CONTACT US newscientist.com/contact General & media enquiries Email media@newscientist.com.au Australia New Scientist Ltd, ABN 22 621 413 170 PO Box 2315, Strawberry Hills, NSW 2012 UK Tel +44 (0)20 7611 1200 25 Bedford Street, London WC2E 9ES US Tel +1 617 283 3213 210 Broadway #201, Cambridge, MA 02139 Australian Newsstand Gordon and Gotch Australia Tel 1300 650 666 Gordon and Gotch New Zealand Tel +64 9 979 3018 Syndication Tribune Content Agency Email tca-articlesales@tribpub.com Subscriptions newscientist.com/subscribe Tel AUS: 1300 130 226 or NZ: +61 2 8355 8923 Email NSAus.subs@quadrantsubs.com Post AUS: New Scientist, Reply Paid 89430, Wetherill Park DC, NSW 1851. NZ: New Scientist, PO Box 210051, Laurence Stevens Drive, Manukau 2154

21 September 2019 | New Scientist | 3

Discovery Tours

E C U A DOR

Darwin’s Galapagos with Jo Ruxton

Departing: 11 days from AU$12,519 7 June 2020

Explore the Galapagos Islands from the comfort of a luxury small-berth yacht Embark on a magical tour and discover a paradise for lovers of natural history, animals and geology, under the expert guidance of marine conservationist and documentary producer Jo Ruxton.

Highlights of the tour include:

Plus

k Explore eight varied islands including

Before setting off, take in

Isabela, Espanola and Fernandina k Exclusive behind the scenes access at the Galapagos Science Centre

Latin America’s largest and best-preserved historic centre and colonial quarters

k Evening briefings from Jo Ruxton

in Ecuador’s capital, Quito,

k Accompanied by local naturalist guides every day

over two days

The Natural Paradise yacht only accommodates 15 people, so enquire early to avoid missing out.

To book or query email newscientist@steppestravel.com or phone UK +44 (0) 20 8108 9520 (UK opening hours Mon to Thu 9-5:30 Fri 9-5 GMT)

newscientist.com/tours

In partnership with Steppes Travel

News Iceland extinction Vikings’ love of ivory was bad news for walruses p7

Infinite lottery 50-year-old maths problem finally solved p13

Pesticide concern Are chemicals contributing to bird declines? p14

Psychiatric disorders Brain network linked to mental health conditions p15

Research ethics The Jeffrey Epstein science-funding scandal p18

Sexual health

JASON O’BRIEN/EPA-EFE/SHUTTERSTOCK

Force often part of first sex experience

Spring fires in Australia Blazes devastating the country’s east coast have arrived unusually early, raising fears about what is to come. Ruby Prosser Scully reports IT IS only just spring in Australia, but bush fire season has already begun, raising concerns that there may be worse to come.

At their height earlier this month, around 140 wildfires were raging across eastern Queensland and north-east New South Wales.

They have destroyed dozens of homes and forced thousands of people to flee. Some of the blazes spanned hundreds of kilometres.

While there are now fewer fires, this could lull people into a false sense of security, says Philip Stewart at the University of Queensland. The latest weather forecasts say the chances of fire are “high” and “very high” across affected areas in the coming days.

A change in the wind direction

or its strength could stoke fires or cause them to alter course, says Stewart. “Until fires are completely out, it is not really good to say that it’s safe.”

A combination of very low humidity, gusty winds and abnormally warm weather led to the conditions that allowed the flames to take hold earlier than usual. Some areas saw temperatures soar 10°C higher than average, while some regions are also into a third year of record low rainfall. The threat of bush fires will be higher than normal in most of the country this summer.

Additionally, several of the recent fires appear to have been started deliberately, says Paul Read at the National Centre for Research in Bushfire and Arson. Police are questioning suspects.

To better manage the bush fire risk, there needs to be greater recognition that Australia is a fire-prone continent and a return to the controlled burning practised

by Indigenous Australians for millennia, says Stewart. “They didn’t just sit back and wait until vegetation was so dry that you had catastrophic fire events as you see now,” he says. ❚

More news articles online Stay up to date with the latest science and tech news newscientist.com/news

ONE in 16 US girls and women were forced into their first experience of sex, either physically or through other kinds of pressure.

The figure comes from an analysis of a national survey run by the US Centers for Disease Control and Prevention.

Laura Hawks of Harvard Medical School and her team analysed the responses from 13,000 women aged between 18 and 44 who answered the survey in the past eight years. The team used the term “forced” for those who said their first experience of sex with a man was “not voluntary”.

About half of those who responded this way said they had been held down. About a quarter were physically harmed and a quarter physically threatened – with overlap between the groups.

About half reported being verbally pressured, such as being told the relationship would end unless they had sex, and a fifth said they had been given alcohol or drugs.

Even when no physical coercion was used, the average age of women forced into sex was 15 and the average age of men was 27, says Hawks. “You’re automatically getting a picture of a huge power imbalance,” she says.

There was less of an age difference for those who first had sex voluntarily: the average age was 17 for the women and 21 for the male partner (JAMA Internal Medicine, doi.org/dbk6). ❚ Clare Wilson 21 September 2019 | New Scientist | 5

News Astronomy

The sound of a black hole Cosmic monsters seem to “ring” in just the way Einstein predicted Leah Crane

note of a bell is determined by its shape, the frequencies of waves produced are determined by the black hole’s mass and spin.

“These frequencies and their lifetimes are inextricably tied to the shape of the bell, so you can listen to the ringing and learn about its structure,” says Isi. The longest-lasting frequency Black holes produce characteristic notes as they merge

is called the fundamental. There are also shorter-lived notes called overtones. “The fundamental rings like a high-quality wine glass, and the overtones are more like a thud,” says Leo Stein at the University of Mississippi.

Isi and his team found an overtone in a signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in 2015. This is the first time anyone has found more than one tone in a gravitational wave.

The mass and spin of the black hole had already been calculated by the LIGO team based on all the information in the signal. Isi and his colleagues have now used just overtone frequency to estimate the mass and spin (Physical Review Letters, doi.org/gf799b).

They calculate that the black hole is about 68 times the mass of the sun and spinning some 100 times a second. That is a good match with the previously calculated value. What’s more, because Isi’s estimate is based on the no-hair theorem, this suggests that the theorem is correct. In other words, Einstein is still right.

The result isn’t very precise.

The black hole’s properties could still deviate from those predicted by relativity by up to 20 per cent.

But there is a good chance that the test can be repeated. “The result was from the loudest binary black hole signal we’ve had so far, but there are more signals that haven’t been analysed yet,” says Katerina Chatziioannou at the Flatiron Institute in New York. Those measurements should allow physicists to nail down whether black holes have hair. ❚

At first, the hiders simply ran away. But, they soon worked out that the quickest way to stump the seekers was to find objects in the environment to hide themselves, using them like a sort of tool. For example, they learned that boxes could be used to block doorways and build simple hideouts.

The real surprise came when the

bots started exploiting glitches in their environment. Seekers found that if they pushed a ramp towards a wall, they could launch themselves into the air and spot hiders from above. Hiders found that they could get rid of the ramps for good by shoving them through exterior walls at a certain angle.

Such tricks show that AIs are able to find solutions that humans miss, says Baker. Maybe the bots will even be able to solve problems that humans don’t yet know how to, he says. ❚ Douglas Heaven

SCIENCE PHOTO LIBRARY

TRY as we might, we can’t prove Albert Einstein wrong. One prediction of his general theory of relativity is that black holes are simple objects. Now listening to them “ring” suggests this is true.

According to general relativity, any black hole can be described by three properties: its mass, spin and electrical charge. In practice, this boils down to the first two, because we don’t expect black holes to accumulate charge.

All other information about a black hole – like the properties of objects that have fallen in – can’t be observed from beyond the event horizon. This information is called “hair” and so the idea is known as the no-hair theorem.

Observations of black holes have all been consistent with this idea. But Maximiliano Isi at the Massachusetts Institute of Technology and his colleagues wanted to test it in a different way: using the ripples in space-time called gravitational waves.

We know that when a pair of black holes merge, the leftover hole should ring like a bell, emitting gravitational waves in several frequencies. Just as the

Machine learning

Bots defy laws of physics to win at hide-and-seek NEVER play games with a bot – it will find a way to cheat. A team from OpenAI, an artificial intelligence lab in San Francisco co-founded by Elon Musk, has developed artificially intelligent bots that learned to cooperate by playing hide-andseek. The bots also learned how to use basic tools and that defying the laws of physics could help them win.

In April, a team of bots known as 6 | New Scientist | 21 September 2019

the OpenAI Five beat the human world champions at team-based video game DOTA 2. Bowen Baker at OpenAI and his colleagues wanted to see if the team dynamics of the OpenAI Five could be used to generate skills that could one day be useful to humans.

The hide-and-seek bots use similar principles to learn but the simpler game allows for more inventive play. The team set the bots loose in a simulation filled with fixed walls and movable boxes and left them to play millions of team games of hide-and-seek.

“Maybe the bots will even be able to solve problems that humans don’t yet know how to”

JAMI TARRIS/GETTY IMAGES

Communication

Vikings probably wiped out Iceland’s walruses

We may share a basic language with chimps

Colin Barras

Clare Wilson

ICELAND was once home to many walruses – and now we have the clearest evidence yet that Norse settlers hunted them to extinction.

We already knew these animals once lived on Iceland, but opinion is divided on whether they vanished before or after humans arrived.

Xénia Keighley at the University of Copenhagen in Denmark and her colleagues carbon-dated the remains of 34 walruses found in western Iceland.

They found that three died after AD 874, when permanent settlers are thought to have arrived. One died only in 1330 (Molecular Biology and Evolution, doi.org/ dbjv). In other words, Icelandic walruses survived for only a few centuries after humans arrived.

In itself, this isn’t proof that humans killed off the walruses, but the researchers suspect that is the case because there are accounts of Vikings hunting the animals, and ivory was valuable to them.

However, the team also considered whether the walruses might have fled from people, as happened on other islands. “When hunters went to Svalbard, the females and calves moved away,” says Keighley.

But the study doesn’t support that idea. The Icelandic animals

WE SEEM to have a natural ability to communicate with chimps. When tested, people can usually understand 10 common hand gestures used by chimpanzees. Human infants use some of these same gestures before they can talk, although we don’t know if their meanings are the same.

The gestures may be the remnants of a basic sign language used by our last common ancestors with other apes, says Kirsty Graham, who did the work with colleagues while at the University of St Andrews, UK. “This gestural communication is probably biologically inherited among the great apes – including humans,” she says.

One idea about language evolution is that we developed the ability to speak by building on a kind of sign language. To investigate, Graham and her colleagues have been recording the gestures of gorillas, chimps and bonobos. So far, they have found 70 or so, with about 16 different meanings, as several gestures can convey the same message. Most are shared by these three great apes.

The team set up a website called the Great Ape Dictionary where the public could watch video clips of 10 common signs made by chimps and bonobos, and choose what each one meant from four options.

By chance, they should get a quarter of the answers right. But they picked correctly 52 per cent of the time, rising to 57 per cent if given a brief description of the situation in which the gesture was used. Some signals – such as a chimp stroking near its mouth, which means it is asking for food – were correctly matched over 80 per cent of the time.

Walrus ivory was a valuable commodity to early settlers on Iceland

have a DNA signature that isn’t found in any other population, suggesting they didn’t interact.

This finding is intriguing, but it is based on mitochondrial DNA, which gives limited information, says Bastiaan Star at the University of Oslo, Norway. ❚

ARCO IMAGES GMBH/ALAMY STOCK PHOTO

Extinction

Graham presented the findings at the European Federation of Primatology meeting in Oxford, UK. In a previous study, Adrian Soldati at St Andrews looked at whether preverbal children used such signals. “Adults don’t need to use gestures so much because

52% of the time people can identify an ape hand signal’s meaning

spoken language is so powerful,” he says. He and his team filmed 13 German and Ugandan infants between 1 and 2 years old interacting with caregivers.

They defined gestures as discrete movements during periods of communication that achieve nothing physically – so it didn’t count if a child pulled their parent towards an object, for instance, but it did if they gave a small, ineffectual tug.

Sometimes, the children seemed to succeed at achieving their goal, but not always.

The group recorded 52 kinds of gestures, about 90 per cent

Some common hand gestures may be shared by all great apes

of which are also seen in chimps. Although they didn’t have enough material to systematically study if the children’s gestures meant the same as those of the apes, Soldati noticed a few such cases.

For example, if a child – or chimp – reaches out with palm uppermost, they are asking for something. “They have this similar toolkit of gesture types that, at least in some of the cases, they used for similar goals,” says Soldati. “We kind of inherited this repertoire.”

But there could be other explanations for the way adults can understand ape gestures, says Thibaud Gruber at the University of Geneva, Switzerland. “Humans can also recognise vocalisations, for example, a strident highpitched call signals danger. You don’t have to invoke [ancestry], acoustics explains it. Some of these gestures are pretty obvious and self-explanatory.” ❚ 21 September 2019 | New Scientist | 7

Special report Ice loss The Alps

Vanishing glaciers As the UN prepares its report on the fate of the world’s ice, Adam Vaughan visits a dramatically changing landscape

distance. Today, visitors are greeted by a slightly sad and largely grey glacier that is about 100 metres lower.

From the station, a short trip by cable car takes me to the height where, in 1988, a visitor could descend down three steps to reach the glacier. There are 580 steps down to the glacier now. Of these, 80 were added this year – a stark illustration of the accelerating effects of global warming.

The fate of the world’s glaciers will be laid bare by the UN climate science panel on 25 September, just days after research is expected to confirm that the extent of Arctic sea ice this summer reached the second lowest level ever recorded.

There are some 170,000 glaciers worldwide covering an area of about 730,000 square kilometres.

Monitoring of 500 glaciers globally shows they are retreating 8 | New Scientist | 21 September 2019

KATIE MOORE FOR NEW SCIENTIST

Mountain guide Andy Perkins says warming is causing havoc

The Mer de Glace glacier.

Aerial shots from 1909 and 2019 (below) reveal how much ice has been lost

France’s two biggest glaciers are a short journey from the popular Chamonix resort LEFT: WALTER MITTELHOLZER, ETH-BIBLIOTHEK ZÜRICH; RIGHT: KIERAN BAXTER, UNIVERSITY OF DUNDEE

KATIE MOORE FOR NEW SCIENTIST

“IT’S very fast. We are confronted with the reality of the retreat,” says glaciologist Luc Moreau about the rapidly vanishing ice at France’s biggest glacier. We are looking at the unmistakeable fingerprint of climate change as told by the historical photos hanging in a hotel overlooking the Mer de Glace, the “sea of ice” near the Alps’ highest summit, Mont Blanc.

About a century ago, women with boaters and parasols sat near the Montenvers train station above the glacier, which then was almost level with a tongue of jagged ice snaking into the

Argentière Montenvers

SWITZERLAND Argentière glacier

Chamonix FRANCE

Mont Blanc

Mer de Glace

ITALY

How we can fight climate change Christiana Figueres tells Adam Vaughan newscientistlive.com

800m France’s two largest glaciers have both lost this much of their lengths over the past 30 years

Many places mentioned in the IPCC report will seem remote to some people, but the Mer de Glace and nearby Argentière glacier are in the heart of Europe, next to Chamonix, a holiday destination visited by millions every year.

Tourists can see the effects clearly. The steps down to the Mer de Glace are punctuated by “level of the glacier” signs from 1985 through to 2015, the year the world agreed the Paris accord to avert dangerous global warming.

At the ice cave carved in the glacier, white sheets have been laid atop the ice to slow the melting.

Sébastien Payot tells me he is running out of ways to adapt.

Since 1946, his family’s business has carved a cave here for tourists every year. But this year, the diggers encountered a spit of rock, indicating that they are nearing the bottom of the glacier.

He fears that the ice’s retreat means next year’s cave will be the last. “It’s a barometer of global warming,” he says.

Recent measurements

by Christian Vincent of the University of Grenoble show that the Mer de Glace and Argentière glacier, France’s second greatest glacier, have both lost around 800 metres in length in the past

three decades. Researchers have gone further back in time by working out the glacier’s depths using photos taken from a balloon in 1909, and comparing them with photos taken from a helicopter more recently (see bottom left).

The lift and the steps down to the shrinking glacier will soon be dismantled if plans by ski-lift firm Compagnie du Mont Blanc go ahead. It hopes to move access to the glacier 500 metres up the valley, and build an educational centre focused on climate change.

“It should allow us to dig a new cave in a place where scientists think there should still be some ice in the next 20 years, even with the most pessimistic scenarios,” says Mathieu Dechavanne at Compagnie du Mont Blanc.

In this area, mountaineers are seeing the changes up close.

“Eighteen years ago, people used to ask ‘have you seen evidence of climate change?’ They don’t ask that anymore, because it’s clear there is,” says Andy Perkins, a British mountain guide who has guided climbers here since 2001.

Warming is leading to more rockfall and thawing permafrost, causing havoc with infrastructure, he says. “You have to take greater care because there is no normal anymore,” says Perkins.

In August, Perkins took a client on the Cosmiques Arête, a route above Chamonix that is considered stable. A day later, a large piece of rock fell from it.

A recent study of 95 Mont Blanc massif climbing itineraries from a famous 1973 book found that all but two of the routes have been affected by climate change.

Becky Coles, part of an all-female team midway through climbing all the 4000-metre peaks in the Alps, found the heatwave in June closed several route options.

It is hard to show rockfall is >

Scientists to be stranded in the Arctic sea ice The biggest scientific project ever to take place in the Arctic is about to kick off. This week, a ship is set to begin drifting in the sea ice off Siberia, where it will become locked in the ice for months of the Arctic winter.

The Polarstern icebreaker is due to depart from Norway on 20 September and is part of MOSAIC, an epic endeavour that will involve some 600 scientists studying climate change, Arctic wildlife and more over the course of a year.

Winter sea ice in the Arctic is too thick even for icebreakers to penetrate.

“It doesn’t make sense to fight the ice, rather we are going to work with it,” says the expedition’s leader, Markus Rex of the Alfred Wegener Institute for Polar and Marine Research in Germany.

The Polarstern, loaded with scientific equipment, fuel and food, will be supported by a fleet of four other icebreakers.

For half a year, the ice will be impenetrable, so a runway on the ice will operate to fly in supplies.

“It’s the biggest sea ice experiment ever.

A once-in-a-lifetime opportunity” The behaviour of the region’s rapidly declining sea ice, which is expected to disappear entirely over summer in coming decades because of climate change, has been well-studied in summer. But for winter, there is little data beyond satellite

ALFRED-WEGENER-INSTITUT / MARIO HOPPMANN

across the board and, since 1960, the rate at which they are losing ice has increased. A leaked draft of a report from the Intergovernmental Panel on Climate Change (IPCC) on our planet’s oceans and ice warns that, this century, melting glaciers will “first give too much water and then too little”.

The Polarstern icebreaker is about to set out on an unprecedented mission images and basic temperature records from ocean buoys, says Rex. The observations from the Polarstern should help build better models of climate change. Rex says some models predict that the Arctic will warm by 5°C compared with pre-industrial temperatures by 2100 but others predict 15°C of warming. The range is huge and needs narrowing, he says.

Donald Perovich from Dartmouth University in New Hampshire, who will be aboard the Polarstern, says the mission should also tell us more about Arctic snow: where it is, how it builds up in winter and melts in summer, and how it is blown around.

The mission should also reveal more about how the bottom of sea ice melts.

“It’s the biggest sea ice experiment ever, by a large margin,” says Perovich. “The number of countries, the number of scientists, the number of icebreakers. It’s a once-in-a-lifetime opportunity.”

21 September 2019 | New Scientist | 9

Special report Ice loss

The melt of Mer de Glace In 1988, it took just three steps to reach the Mer de Glace glacier from a lift stop.

Today, it takes 580 to reach the glacier and the ice cave carved into it 1988: 3 steps 1990: 12 steps

2000: 118 steps

Steps lead down to the Mer de Glace glacier (above). An ice cave (left) is dug in the glacier every year

2010: 321 steps

ICE CAVE 2019: 580 steps

KATIE MOORE FOR NEW SCIENTIST

2015: 370 steps

SOURCE: COMPAGNIE DU MONT-BLANC

Greenland

Meltwater could raise sea level an extra 7 centimetres MELTING and refreezing is turning the absorbent surface snow of Greenland into solid ice. This means more water is draining straight into the sea instead of soaking into the snow and refreezing deeper down.

Now a study suggests that this will cause an extra sea level rise by 2100 of at least a few centimetres.

“As a human and a father of three, it’s a little terrifying,” says Michael MacFerrin at the University of Colorado, whose team discovered the effect.

The Greenland ice sheet is made of snow. Deeper layers gradually turn to ice, but the surface used to consist almost entirely of porous snow. When parts of it melted, the water sank through the snow and refroze deeper down, forming chunks of ice.

10 | New Scientist | 21 September 2019

Extracted ice cores and radar observations show that surface melting is becoming so common and widespread in Greenland that these bits of ice are getting larger and joining up to form extensive solid slabs.

“This process really is transforming the surface of the ice sheet in the interior of Greenland,” says MacFerrin.

At present, almost all ice loss from Greenland is a result of glaciers flowing faster into the sea.

2-7cm The predicted extra rise in sea level caused by surface snow turning to ice According to a recent survey of climate scientists, Greenland ice loss alone could add 33 centimetres, or maybe even 100 centimetres, to global sea level by 2100.

In parts of Greenland, however, meltwater now runs over the

surface of this ice rather than sinking into snow. This was first observed in 2012, when there was extensive surface melting across Greenland.

Now computer modelling by MacFerrin’s team suggests that meltwater runoff from the interior could add somewhere between 2 and 7 additional centimetres to sea level by 2100 (Nature, DOI: 10.1038/s41586-019-1550-3).

That is roughly double previous estimates that don’t take this slab-forming effect into account.

The good news is that it isn’t a runaway process that can’t be reversed, such as the nowinevitable collapse of the West Antarctic ice sheet. If surface melting was reduced, a porous snow layer would build up again.

“This is completely dependent on atmospheric temperatures,” says MacFerrin. “If you stop the warming, you stop this effect.” ❚ Michael Le Page

getting worse because of a lack of data, she says, but it feels worse than in the past. “I think there’s more rockfall, without a doubt.”

The heatwave was made more probable by climate change.

The retreat of the glaciers is affecting flora and fauna too, says Hillary Gerardi of the Research Centre for Alpine Ecosystems in Chamonix. “We are seeing the productivity of vegetation going way up, plants are moving up the slope and the growing season is getting longer,” she says, citing the example of a large tree that was found growing above Chamonix where a glacier had been situated just a decade ago.

Another example comes from the keeper of the Vignettes hut, a stop on a popular walking route in the area. A local plant known as génépi, used to make an alcoholic drink, is usually picked at about 2400 metres above sea level.

This year, the keeper picked it at 3100 metres, the highest so far.

Meanwhile, some species will lose out, like the rock ptarmigan, a bird whose Alps habitat is shrinking.

The world is currently on the path to dangerous warming, but on 23 September, some 60 heads of state are expected to present new climate change plans at a UN summit in New York. The UN special climate envoy, Luis Alfonso de Alba, says the European Union’s contribution will be fundamental to the meeting’s success.

Unless global action is taken to curb carbon emissions, France’s two greatest glaciers are doomed.

A recent study by Vincent shows that on the current emissions trajectory, Argentière will be gone by 2080 and Mer de Glace by the end of the century.

“Almost nothing” can be done locally to stop their decline, he says. Their future rests on the course the world takes. ❚

Adam Vaughan is chief reporter at New Scientist and tweets as @adamvaughan_uk

Food for thought Give your mind a healthy balanced diet with a New Scientist subscription

Why limit yourself to 5 a day? )URP TXDQWXP SK\VLFV WR DUWLÄ·FLDO LQWHOOLJHQFH IURP FOLPDWH FKDQJH WR KXPDQ KHDOWK DQG VR PXFK PRUH JLYH \RXU PLQG WKH ULFKHVW GLHW RI ZRUOG FKDQJLQJ LGHDV ZKHQ \RX VXEVFULEH

)RU HDV\ VLJQ XS YLVLW

newscientist.com/13563 Or call 1300 130 226 or +61 (0)2 8355 8923, quoting reference 13563 Savings based on a print + digital subscription to New Scientist made payable on an annual term. Offer closes 9th October 2019

News Astronomy

A second interstellar tourist?

Mysterious comet heading our way may come from another star Leah Crane

EXCITEMENT is building among astronomers following the sighting of an object that seems to have come from outside our solar system. If its origins are confirmed, it will be only the second interstellar object we have detected. And unlike the last, this one is heading our way.

The first interstellar object, an asteroid called ‘Oumuamua, was discovered in October 2017.

When we spotted it, it was already on its way out of the solar system and moving so fast that it was difficult to study.

The new object is a comet, spotted in images from the Crimean Astrophysical

Observatory on 30 August. Its trajectory seems to indicate that it came from beyond our solar system, from the direction of the constellation Casseiopeia. It was initially known only as gb00234, but is now being called comet Borisov, after the astronomer who first spotted it, Gennady Borisov.

Other astronomers have now taken more than 150 pictures of the object to try to nail down its path. “We had one like this in late May and it turned out to be a normal comet,” says Michele Bannister at Queen’s University Belfast, UK. We don’t have enough data yet to know whether Borisov came from outside our solar

The world demands more energy.

12 | New Scientist | 21 September 2019

system, she says. “It’s a bit under-baked as yet.”

Bill Gray, an independent astronomy software developer, has modelled the object’s path.

“It’s either a really bright interstellar comet, or it’s getting

“It’s either a really bright interstellar comet, or it’s getting pushed around by non-gravitational forces” pushed around a lot by nongravitational forces,” he says.

It could be that material on the comet is evaporating, creating a propulsive force that has forced it into a strange orbit. “Both are a

little hard to believe, and we’ll probably have to wait for more data,” says Gray.

If it is an interstellar comet, Gray’s modelling suggests that it is heading towards us at about 30 kilometres per second and will pass Earth in December. When it passes us, it should be about twice as far from us as the sun is.

This comet was caught much earlier in its journey through the solar system than ‘Oumuamua, which will make it easier to observe. This could give us a unique opportunity to study a rock from around another star and perhaps learn what other solar systems are like. ❚

The world demands less carbon.

Can we use maths to clean our oceans?

Find out from Tom Crawford on 11 October newscientistlive.com Infinity

Mathematicians crack 50-year-old problem IN AN infinite lottery, can you create a lottery ticket that always wins? This is the idea behind a 50-year-old maths problem that has now been solved.

In a standard lottery, you have a ticket with a handful of numbers on it and if they match the randomly selected numbers from the lottery, your ticket wins.

Each ticket can have several rows on it, giving you several chances to win. This means that a long enough ticket could in principle have every possible winning combination, so always wins. It would cost so much money to do this in reality, however, that it wouldn’t be worth it.

Can the world have both?

But in a hypothetical infinite lottery, things are a little different.

The winning collection of numbers is infinitely long, and each ticket can have an infinite number of rows, with each row containing an infinite number of numbers. In fact, the ticket can be so large that the rows can’t even be numbered, which is called being uncountable.

In this situation, it is far less obvious whether it is possible to create a ticket that always wins.

It is now half a century since mathematician Adrian R. D. Mathias first posed the question, and David Schrittesser and Asger Törnquist at the University of Copenhagen in Denmark have found an answer:

GETTY IMAGES

Chelsea Whyte The normal lottery is somewhat easier to win than an infinite lottery

it isn’t possible to have a ticket that always wins the infinite lottery.

About 20 years ago, some mathematicians rediscovered the problem and started to make progress. “Nobody took the slightest notice for 30 years, and then suddenly people got interested again. It’s very satisfying to see,” says Mathias.

It has taken Schrittesser and Törnquist four years to solve the puzzle.

The pair used ideas from Ramsey theory to tackle the problem, a part of mathematics that looks at how order appears in a large structure.

They found that in an infinite lottery, a sort of structure arises that means the winning numbers clump together, but in a way that means a ticket that always wins just can’t exist (PNAS, doi.org/dbjk).

“With these kinds of problems, you don’t sit down and say I’m going to be the one who solves it, because everyone has tried,” says Schrittesser. “There’s a little bit of serendipity.” ❚

We see possibilities everywhere.

From renewable energy and cleaner-burning natural gas to advanced fuels and new low carbon businesses, BP is working to make energy cleaner and better.

Natural gas burns 50% cleaner than coal in power generation.

21 September 2019 | New Scientist | 13

News Biodiversity

Maths

Pesticides could be partly to blame for bird decline

Riddle that looks like a pile of worms is nearly cracked

Michael Le Page

Ben Skuse

KURT STRICKER/GETTY

BEES can be harmed by low levels of neonicotinoid pesticides, and now it seems birds can too. Migrating whitecrowned sparrows have been found to lose weight after eating seeds treated with one of these chemicals, imidacloprid, delaying their onward migration by several days.

Such a delay could hamper their chances of successfully breeding. However, the main manufacturer of the pesticide disputes the findings.

The latest twist in the debate over neonicotinoids is the result of work by Christy Morrissey at the University of Saskatchewan in Canada and her team. They caught migrating sparrows, tagged them with tiny radio transmitters and gave them feed containing imidacloprid or an alternative without the chemical. The birds given the pesticide lost up to 6 per cent

of their body weight in the 6 hours before release, whereas the other birds hardly lost any.

Scans also showed a decline in body fat among the first group.

When released, the birds not fed imidacloprid continued their migration after half a day.

Those given the pesticide took four days, on average, to do the same (Science, doi.org/dbg6).

57 out of 77 species of farmland bird in North America are in decline

Morrissey says she also has unpublished evidence that two other neonicotinoids have similar effects.

Birds that arrive late at breeding grounds are less likely to raise young successfully and may not breed at all, says Morrissey. “This has serious impacts on populations.”

The study shows sublethal doses of neonicotinoids can have adverse effects on seed-eating birds as well as on beneficial insects such as bees, says Caspar Hallmann of Radboud University in the Netherlands. “Birds – especially small birds – are really dependent on having sufficient body fat during migration.”

The findings are disputed by Bayer, the main manufacturer of imidacloprid. Real-world neonicotinoid exposure levels are far below those that disrupt migratory behaviour, and the pesticides are safe when applied according to instructions, says a Bayer spokesperson.

Morrissey says the birds were given realistic amounts. They could get the highest dose given in the study by eating just onetenth of a treated maize seed, a fifth of a soya bean or three canola seeds, for instance. “It’s tiny, tiny amounts,” she says.

In North America, 57 of the 77 bird species associated with farmland are in decline, with neonicotinoids one possible factor. However, Morrissey says that banning these pesticides isn’t the answer because farmers will just use alternatives that may turn out to be as bad.

Instead, we need to find ways of farming that don’t rely on quick chemical fixes, she says.

“The regulatory system keeps failing, by allowing new harmful chemicals into use,” says Dave Goulson at the University of Sussex in the UK. “The only long-term solution is to move away from a reliance on pesticides to solve every problem.” ❚ The white-crowned sparrow is a native of North America

14 | New Scientist | 21 September 2019

WE ALMOST have a solution to a fiendishly tricky mathematical riddle first posed 82 years ago.

The Collatz conjecture is easy to state. Start with any positive whole number. If it is even, divide it by 2.

If it is odd, triple it and add 1.

Whatever the result, follow the same steps as before, again and again, building a sequence. The conjecture says that whatever number you start with, you eventually get 1 as the answer.

The sequence can be depicted visually to show lines all wiggling their way back to the same spot.

This looks a bit like fronds of waving seaweed or a pile of wiggly worms.

The conjecture has been verified up to the starting number of 1020 (100 quintillion). However, proving it absolutely involves not just checking more numbers but also finding a reasoned mathematical explanation that it is always true.

Now Terence Tao at the University of California, Los Angeles, seems to have almost got that. His work builds on that of other researchers, who proved that almost all sequences were at least able to reach an intermediate value between their starting number n and 1. This means they can’t balloon to infinity.

Tao has managed to go further (arxiv.org/abs/1909.03562).

“I showed that one could move this intermediate milestone to be as close as one wishes to the final goal 1 for almost all n,” he says.

Jeffrey Lagarias at the University of Michigan says Tao’s work is “the most significant progress on the problem in many years”.

However, Tao says there is little hope of using his methods to find a complete proof. He writes that this is “well beyond [the] reach of current methods”. This is because he relies heavily on techniques from probability theory, meaning there is always a small chance of failure. ❚

Hear Linda Geddes talk about how sunlight shapes our bodies and minds at New Scientist Live on 11 October newscientistlive.com ECNP conference round-up Mental health

Light therapy may help relieve symptoms of perinatal depression Jessica Hamzelou

three circadian genes were more active and one was less active in the women who had been diagnosed with depression.

The team also found that the more methyl groups there were, the more severe a woman’s symptoms were likely to be.

This suggests that the greater

the difference in circadian gene activity, the more likely a woman is to experience symptoms of depression, say Buoli and Esposito.

The pair presented their findings at the European College of Neuropsychopharmacology annual meeting in Copenhagen.

“The work is tremendously exciting,” says Katherine Sharkey at Brown University, Rhode Island.

In her own research, Sharkey has found that using a light box to mimic natural daylight improves the symptoms of perinatal depression. In a small

Brain network linked to multiple mental health conditions

treatments might have caused changes to the brain.

Instead, his team turned to children aged between 3 and 18, none of whom had been diagnosed with a psychiatric condition. Any differences in brain structure among children are more likely to be explained by genes rather than the effects of an established disorder or treatment, says Taquet.

Using data from 678 children in the US, the team searched for 1877 genetic factors linked to a range of psychiatric conditions, including schizophrenia, panic disorder and addiction. Each child was given a score based on their overall genetic

A SET of brain structures appears to be implicated in depression, schizophrenia and other mental health conditions, delegates at the European College of Neuropsychopharmacology annual meeting heard last week.

“We know for psychiatric illnesses, the categories of diagnosis are not very reliable,” says Maxime Taquet at the University of Oxford. Psychiatric disorders have been shown to overlap when it comes to which genes they are linked to, as well as symptoms.

Taquet and his colleagues wanted to find out how these shared genetic factors might influence a person’s brain structure. Looking at the brains of adults with established disorders might not answer the question, as the disorder or any

SUDOK1/GETTY

“Four circadian genes showed different activity in the women diagnosed with depression”

Circadian rhythms appear to be disrupted in pregnancy

GETTY IMAGES

WOMEN with perinatal depression appear to have altered circadian rhythms. Using light to reset the body clock seems to improve their symptoms.

Our bodies run on internal clocks that are regulated by a suite of genes. In concert with light, they wake us up in the morning and leave us sleepy by night-time.

People with severe depression tend to have disrupted circadian rhythms, experiencing daytime sleepiness and night-time insomnia. Research has found higher activity in some circadian genes in people with the condition.

Perinatal depression – which occurs during and after pregnancy – seems to be similar.

Women tend to get less sleep when they are pregnant, particularly if they have perinatal depression.

To find out if circadian genes might play a role, Massimiliano Buoli and Cecilia Maria Esposito of the University of Milan, Italy, analysed seven genes in 44 women in the third trimester of pregnancy. Thirty of the women were diagnosed with perinatal depression.

By looking at whether epigenetic tags called methyl groups were attached to the genes, the researchers and their colleagues could tell how active these genes were. They found that

Genetic factors involved in mental health may influence brain structure

unpublished trial of 44 women with the condition, she found that those given a light box and sleep routine alongside routine treatment saw their symptoms improve. “Everybody got better, but the women given a circadian intervention did better [than those without],” says Sharkey.

Sharkey doesn’t yet have enough evidence to recommend the treatment more widely, but there is evidence that a good sleep routine and outdoor exposure to sunlight is beneficial for mental health. “In a typical office space, the light level is 300 to 400 lux, but on a bright, sunny day, outside can be 50,000 lux,” says Sharkey. ❚

risk for mental health issues.

Brain scans revealed “large differences” between the brains of high-risk and low-risk children, says Taquet. The team describes the affected regions as the “vulnerability network”, and it includes the default mode network, which is active when the brain is at rest, plus regions involved in planning and vision.

The findings add weight to the idea that seemingly different disorders have a lot in common, says Taquet. “The psychiatric disease categories we have, such as depression, bipolar disorder, schizophrenia and anxiety disorder, are not that different in the end, from a biological point of view.”

Annika Hulten, a medical adviser for pharmaceutical firm JanssenCilag in Helsinki, Finland, says the work is “impressive and promising”.

But she says it is too soon to know if this network would make a good target for future treatments. ❚ JH 21 September 2019 | New Scientist | 15

News In brief Animal behaviour

Crabs unleash their inner growl when intimidated

THEO ALLOFS/GETTY IMAGES

GHOST crabs can “growl” by grinding the teeth inside their stomach. While many crustaceans have such teeth to aid digestion, the ghost crab is the first that has been shown to use them to communicate as well.

It has long been known that ghost crabs (pictured) use noise to deter intruders by flexing their claws, making ridges near the joint rub against each other. But when an animal gets too close, the crabs hold their claws upright, which prevents them making these sounds.

Jennifer Taylor at the Scripps Institution of Oceanography in California noticed that even in this position, the crabs still make a rasping sound when threatened.

She and her colleagues couldn’t tell what was causing the noise, so they used X-ray videos to see what was Exoplanets

A PLANET twice Earth’s size with water in its atmosphere has been spotted 110 light years away. It may be the best place found so far to seek life beyond our solar system.

Björn Benneke at the University of Montreal in Canada and his colleagues used the Hubble space telescope to observe the alien world, called K2-18 b, as it passed in front of its star. This is the first time the atmosphere of a planet of this size has been characterised.

Benneke’s team and another led

by Angelos Tsiaras at University College London looked at the edges of the planet as it transited its star so that light shone through the atmosphere, allowing them to analyse what it was made of.

They found distinct signs of water vapour. K2-18 b is also in the habitable zone around its star, defined as the area where a planet could maintain liquid water on its 16 | New Scientist | 21 September 2019

Physiology

surface (Nature Astronomy, doi.org/dbgp).

“This is the only planet that we know of right now outside our solar system that is in the habitable zone, that has an atmosphere and that has water in it, which makes it the best candidate for habitability we know of,” said Tsiaras at a press conference.

Planets like this one, between the size of Earth and Neptune, are common around other stars, but their atmospheres are difficult to study compared with those of larger worlds.

While K2-18 b probably does have a rocky core, it is likely to be mostly gaseous, making it more similar to Neptune than Earth, says Laura Kreidberg at the Harvard-Smithsonian Center for Astrophysics in Massachusetts.

“The jury is still out on whether a planet like this could be habitable.

If there were life there, it definitely wouldn’t be like life as we know it on Earth,” she says. Leah Crane

Bones fire up body’s response to danger YOUR skeleton secretes a hormone that helps to coordinate the flightor-fight response, suggesting this part of our body is far from inert.

When faced with a sudden threat, our heart and breathing rate, blood pressure, circulating blood sugar and body temperature increase to prepare our muscles for action. This response is known to be controlled by nerve pathways from the brain and hormones

DOUGLAS SACHA/GETTY IMAGES

Watery alien world best bet yet for life

happening inside the crabs as they growled in response to various threats. These revealed that the rasping coincided with movements of the teeth in the crabs’ foreguts, known as gastric mills, and that the teeth weren’t grinding up food at the time (Proceedings of the Royal Society B, doi.org/dbgj).

Many animals, from worms and molluscs to birds, have mechanisms for grinding food in their gizzards that can produce audible noises (though birds swallow stones rather than having internal teeth – as did dinosaurs). Taylor suspects that some of these animals also use these noises for communication.

Some fish, such as grunts, produce sounds using the teeth in their throats. This is the closest known equivalent to the ghost crabs, says Taylor. Michael Le Page

released by the adrenal glands.

Now, Gerard Karsenty at Columbia University in New York and his colleagues have discovered that a hormone released by bones called osteocalcin also has a role.

They found that blood levels of osteocalcin quickly rose in people when stressed. The same thing happened in mice and rats (Cell Metabolism, doi.org/dbgh).

The results build on the group’s earlier work showing that bones release osteocalcin to help muscles burn fuel during exercise, and that osteocalcin injections in older mice make ageing muscles more youthful. Together, these findings suggest we need a radical rethink of the role of bones, which have previously been viewed as mostly inert structures, says Karsenty.

The body may have different ways of mounting a flight-or-fight response so we have back-ups in place in case one system fails, says Robin McAllen at the University of Melbourne in Australia.

Alice Klein

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

Really brief

Free energy even when the sun sets

LEANDRO SOUSA

A DEVICE that makes electricity at night using heat rising from the ground could be used to power lights and phones in remote spots.

More than 1 billion people globally, chiefly in poor, rural communities, still lack an electricity supply. Cheap solar cells are increasingly used to power lights, mobile phones and home appliances in these communities, but they work only during the day.

Now, Aaswath Raman at the

Two new species of electric eel found It was thought that there was only one species of electric eel. Now two more have been discovered, one of which (Electrophorus voltai, pictured) delivers a record jolt. All three species are found in South America and can produce between 650 and 860 volts (Nature Communications, doi.org/dbdr).

Giant ice age kangaroos had “absurdly huge cheekbones”, which helped them munch tough branches. The finding came from creating a digital model of a skull of Simosthenurus occidentalis, an extinct kangaroo that lived until around 42,000 years ago (PLoS One, doi.org/dbdq).

Tower is made of self-shaping wood A method for producing bent wooden panels could make it easier to create curvy buildings. The technique involves the use of wooden sheets designed to bend as they dry and has been applied for the first time to build a 14-metre-tall twisting tower in Germany (Science Advances, doi.org/dbh9).

Astronomy

on the inside. The black disc was designed to cool by losing heat to the sky, while the aluminium block was designed to warm up by absorbing heat from the night air. A thermoelectric generator then converted the temperature difference to electricity.

It produced 25 milliwatts of power per square metre when tested on a roof in California on a clear night, enough to switch on an LED light (Joule, doi.org/dbgm).

The output would probably be 20 times better in hotter climates, says Raman. However, cloud and rain may hinder it. AK Robotics

Is it a bird? Is it a fish?

No, a leaping waterbot

SOUTH AFRICAN RADIO ASTRONOMY OBSERVATORY

Ancient kangaroos had crushing bites

University of California, Los Angeles, and his colleagues have invented a $30 device that makes electricity at night using the thermoelectric effect – in which temperature differences can be converted to electricity.

Raman and his team created a temperature difference using a mechanism called radiative sky cooling, which causes sky-facing surfaces to become colder than the surrounding air as they naturally radiate heat into the sky. They constructed a box with a black disc on the outside facing upwards and an aluminium block

Giant space bubbles found near heart of the Milky Way THE centre of our galaxy has blown some bubbles. Astronomers using the MeerKAT telescope in South Africa have found a pair of vast balloons of high-energy particles above and below the Milky Way’s central supermassive black hole.

MeerKAT can detect synchrotron radiation that is caused by charged particles like electrons moving near the speed of light. Farhad Zadeh at Northwestern University in Illinois and his colleagues used it to map the area near our galaxy’s core.

They found two huge bubbles protruding from the area around the supermassive black hole at the centre of the galaxy, perpendicular

to the galactic disk (Nature, doi.org/dbgn). They are just visible as smoky smudges above and below the bright central line of the galaxy in the picture above.

The particles in them must have been accelerated by a powerful event at the middle of the Milky Way, perhaps the black hole gobbling lots of material and causing a big flare.

The bubbles may be related to another cosmic mystery. More than 100 filaments of magnetised particles were discovered about 35 years ago, and we don’t know how they formed or why they emit radio waves. These strands are within the bubbles. LC

LIKE a flying fish gliding above the waves, a robot can propel itself out of water into flight.

Mirko Kovac and his colleagues at Imperial College London have developed a robot that can lift itself out of water and travel through the air for up to 26 metres.

It weighs 160 grams and could be used for monitoring the ocean, taking samples by jumping in and out of the water in cluttered environments, avoiding obstacles such as ice in cold regions or floating objects after a flood.

The robot consists of a small tank that refills with water from its aquatic surroundings. It is powered by calcium carbide, a chemical powder that reacts with water to produce combustible acetylene gas. When the gas is ignited by a spark, it expands, pushing a jet of water out that propels the robot into the air.

It can jump multiple times after refilling with water, which could allow it to take several samples per trip.

The team tested the creation in a lab, lake and wave tank. The next stage is to see whether it could be used to monitor the oceans around coral reefs and offshore energy platforms (Science Robotics, doi.org/dbgk). Donna Lu 21 September 2019 | New Scientist | 17

News Insight Research ethics

Dirty money?

ALAMY; SHUTTERSTOCK

THE revelation that financier Jeffrey Epstein was funding high-profile scientific research even after he had been convicted of sex offences has rekindled a debate about who funds science.

How do we decide what sorts of donation are ethical, and to what extent does it matter where research funds come from?

The scandal over Epstein’s science funding came to a head on 7 September, a month after Epstein died by suicide. It was then that Joichi Ito, director of the Massachusetts Institute of Technology (MIT) Media Lab, resigned. He admitted to accepting some $1.7 million from Epstein, both for the Media Lab, an interdisciplinary research group, and his own investment funds. Epstein had been convicted in 2008 of sexually abusing girls as young as 14.

Ito’s acceptance of Epstein’s money wasn’t a crime, but this is an ethical grey area. Articles in the media, and discussions between scientists at MIT, have suggested that Ito’s actions were wrong

Joichi Ito (left) accepted money from sex offender Jeffrey Epstein (right)

because they burnished Epstein’s public reputation by associating him with respected scientists.

That view isn’t universal. In an essay last week, Lawrence Lessig at Harvard University argued that taking Epstein’s money could have helped MIT’s research without ameliorating Epstein’s 18 | New Scientist | 21 September 2019

NEMANJA TRIFUNOVIC/ WWW.MEDIA.MIT.EDU

In the wake of the Jeffrey Epstein science-funding scandal, we need to talk about where money for research comes from, writes Chelsea Whyte

profile, as long as the money was taken anonymously. Ito did indeed ensure that the money he accepted from Epstein was kept anonymous.

Such debates over Epstein’s funding of science have prompted the question: are there good enough systems to allow people to collectively decide which sources of research funding they are happy with?

This goes far beyond Epstein.

The tobacco industry once funded a lot of health research with the purpose of improving its own reputation. Today, Facebook funds research into the effects of social media on democratic processes, despite being seen by some as a platform from which democracy can be manipulated. There are plenty of other examples of research institutions taking money from sources that

some people think are improper (see “Money trouble”, right).

It is an apt time to ask these questions, because research institutions are facing a fragile funding environment. “Until the financial crisis, science had benefited from pretty steady annual growth rates. Now, government funding has started to decline or plateau,” says Jack Stilgoe at University College London. Research institutions really need cash and so “they are more likely to get themselves in this kind of trouble”, says Stilgoe.

$1.7m Amount of money that Joichi Ito says he accepted from Jeffrey Epstein

MIT’s Media Lab combines research from technology, media, science and art

Government-backed organisations like the US Office of Research Integrity, and the UK equivalent, offer guidelines on how to avoid conflicts of interest and conduct research responsibly.

These touch on funding, often stipulating, for example, that funders shouldn’t be able to influence what results get reported. But funding decisions aren’t overseen by independent bodies. At universities, they are usually made by a funding office.

When science is primarily funded by the public, measures like this may be sufficient. But Stilgoe says that during the 20th century, sources of funding have diversified, with the military and others giving more money

Working hypothesis

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

The Massachusetts Institute of Technology Media Lab isn’t the only place to have accepted donations from sources that some consider inappropriate (see main story).

The London School of Economics came under fire in 2011 for accepting money from a foundation run by Libyan dictator Muammar Gaddafi.

In the same year, the University of California, Los Angeles, accepted $10 million from Lowell Milken to set up a business law institute.

He had been indicted for racketeering and fraud.

New York’s Metropolitan Museum of Art has a wing named after the Sackler family, who own Purdue Pharma, which has been accused of stoking the opioid crisis in the US. The museum said in May that it would stop accepting donations from the family.

Many other places have financial links to the family too, including an imaging laboratory at London’s Natural History Museum.

with strings attached. “Scientists have not been great at talking about the conflicts of interest that come with that,” he says.

There is no commonly adopted ethical framework to guide these decisions, although some have tried to create one. One attempt is the Missenden Code of Practice for Ethics and Accountability, developed by Rory Daly who is now at Lancaster University, UK.

The code says universities should create an ethics committee that includes representatives of students, staff and the local community, and that this should vet every source of funding.

John Wakeford at the Missenden Centre near High Wycombe, UK, worked with Daly on the code.

He says the idea was well received by ethicists, but university funding offices didn’t widely adopt it.

A 2011 seminar for university development officers to discuss funding ethics garnered interest from only two people, he says.

The inclusion of staff and students on such a panel could alleviate funding concerns before they turn into a fiasco, says Wakeford. Without this kind of transparency, universities can put their staff in unethical positions without their consent.

That was true for Ethan Zuckerman of the Media Lab. He was unaware that the lab had received funding from Epstein, and resigned in protest when he found out. In a blog post, he wrote that his work focused on social justice and that it was “hard to do that work with a straight face” in a place that had worked with Epstein.

However, a Missenden-style committee wouldn’t necessarily have helped in the MIT case, because Ito concealed where the money came from. A committee can’t vet donations it doesn’t know about.

Does this mean that we need a regulatory body with sharp teeth to force all donations to science into the light of day?

We may not need to go that far.

Kieron Flanagan at the University of Manchester, UK, says that autonomy is baked into the principles guiding universities and that this scandal may well prompt them to revisit their rules.

“When a scandal comes along, as it does periodically, institutions respond to that in a scramble and maybe set their own principles for what funding they’ll accept,” he says.

It is also clear that not all scientific funding is suspect, says James Wilsdon at the University of Sheffield, UK. Public funding is well regulated. And many private donations are directed towards specific research or particular labs, which often makes the expectations clear.

▲ Vegemite flies A balloon has carried two slices of Vegemite on toast 100 kilometres into the atmosphere.

Your move, Marmite. ▲ Superbolts We now know that lightning bolts that are 1000 times stronger than average mainly strike at sea, particularly at a hotspot near Japan.

$10m

▲ Moon elevator

Amount donated to the University of California, Los Angeles, by someone indicted for fraud

The problem lies elsewhere, when money is donated to particular teams or institutions without a stipulated goal or aim.

“Shovelling money into this grey space that exists above individuals and specific projects makes it possible not to see the fingerprint of that funding,” says Wilsdon.

One reasonable way to encourage transparency around this type of funding, says Wilsdon, could be to legally require all donations to research institutions to be made public if they are over a certain amount. This approach already exists in politics, so we know it is workable.

One thing is sure: these questions aren’t going away.

And it is probably going to be prestigious labs that face them most often. On the one hand, they are a magnet for rich individuals looking to make a statement.

On the other, they already have enough money to carry out due diligence. “It should be easier for them to say no,” says Flanagan. ❚

A cable tethered to the moon rather than to Earth could be a more feasible way of building a space elevator to our nearest neighbour. ▼ Nappy changer An inventor who patented an “automatic nappy changer” has won an Ig Nobel prize. Who wants to put their child in first? ▼ A load of dung A story about an Inuit man who made a knife from his frozen faeces may not be entirely true. When ethnographers made one, the blade melted when they tried cutting meat.

GETTY IMAGES/ALAMY

Money trouble

Sorting the week’s supernovae from the absolute zeros

21 September 2019 | New Scientist | 19

SAVE 15% USE CODE FINAL15

JOIN US AT THE WORLD’S GREATEST SCIENCE FESTIVAL 10 -13 October | ExCel London

BIG THINKERS

OLA ROSLING • CAROLINE CRIADO-PEREZ • LEE BERGER • ALICE ROBERTS • AVI LOEB

GELONG THUBTEN AND ASH RANPURA • MEGAN ROSSI • PAUL DAVIES • MAGGIE ADERIN-POCOCK MARTIN REES • MARCUS DU SAUTOY • LIZ BONNIN • ROBERT PLOMIN • JO DUNKLEY • VLATKO VEDRAL JOANNA BRYSON • MARK MASLIN • JACQUELINE MCGLADE • GEOFF SIMM • GINA RIPPON • AL WORDEN

BIG IDEAS AND BIG ISSUES

IS MARS HABITABLE? • ARE WE ALONE? • WHAT HAVE INSECTS DONE FOR US? CANNABIS AND MENTAL HEALTH • THE FUTURE OF HEALTHCARE • THE FUTURE OF ENERGY HOW CLIMATE CHANGE IS AFFECTING AIR TRAVEL • IS GAMING BAD FOR US?

WEIGHING FORESTS FROM SPACE • IN PURSUIT OF ONLINE PRIVACY • WHAT’S THE POINT OF DADS? FIXING THE PLASTIC WASTE PROBLEM • AIR QUALITY • THE TRUTH ABOUT DIETS

FOR CURIOUS MINDS

BOBBY SEAGULL • DOCK A SOYUZ SPACECRAFT • LEVITATING WITH SOUND

CARNIVOROUS PLANTS • SUPERHUMANS • MARS ROVER • RELICS FROM THE MARY ROSE DINOSAURS OF BRITAIN • WHAT WE CAN LEARN FROM ANCIENT TECHNOLOGIES • OUMUAMUA SCIENCE COMEDY QUIZ • AFTER-DARK DISCO • HOW EARTH MADE US • CONSERVATION DRONES WHY DO SMART PEOPLE DO STUPID THINGS? • GUT HEALTH • AGEING • THE SCIENCE OF FATBERGS

Only three weeks to go! Visit newscientistlive.com and use code FINAL15 *Valid on Standard and Friday Night Late tickets

SPONSORS AND PARTNERS

Views The columnist Annalee Newitz on tech firms’ union confusion p22

Letters There are several approaches to saving the Arctic Ocean p26

Aperture Rival mudskippers tussle for territory in Japan p28

Culture Inside the antiscience world of The Testaments p30

Culture columnist Roguelike games can’t be truly random, says Jacob Aron p32

Comment

Climate strikes grow up The school strike for the climate movement is looking for adult support on 20 September. We should give it, argues Alice Bell

JOSIE FORD

I

T IS just over a year since Swedish teenager Greta Thunberg, frustrated by political inaction on climate change and following Sweden’s hottest summer in more than 250 years, skipped school and sat in front of the Swedish parliament with a handwritten “Skolstrejk för klimatet” (School strike for the climate) sign.

Before long, teenagers in other countries were following her lead, building momentum towards the global Fridays for Future school strike movement. They have brought a new energy, bluntness and charisma to the climate debate – and shown spectacular skill at embarrassing politicians.

On 20 September, they are asking adults all over the world to join them in showing up on the streets. Whether you are an employee, employer or neither, it’s worth asking what you can do to answer that call.

If nothing else, this is a chance to show a positive spirit of intergenerational cooperation on an issue that could be very generationally divisive – and in a world increasingly scarred by such conflict. Climate change is an issue for us all. We should send a clear signal that we know delegating it to the young to sort out will leave it too late.

Australia shows how support can be mobilised. It was one of the

first places outside Sweden to spark a youth strike. By dint of their nation’s location on the globe, Australians will be some of the first to strike. There, the Not Business As Usual coalition of employers has pledged to support the strike, whether by closing company doors, having a meeting-free day, allowing a longer lunch break to attend protests or just making it clear that teams won’t be penalised for taking a few hours off.

In the UK, the Trades Union Congress has voted to support 30 minutes of solidarity action on the day. As the strike begins across the Atlantic, more than 1000 employees at Amazon will

also walk out, part of the longstanding Amazon Employees for Climate Justice campaign.

If you can’t leave work, there are still plenty of ways to aid the strikers. You could donate some of your wages to a climate campaign or write to schools, local papers and political representatives in support of the protests.

Above all, the young strikers want to see more people taking increasingly ambitious climate action. The most helpful thing any of us can do is look around, decide what needs to change and resolve to make that change happen.

That can’t end with a 30-minute microstrike on 20 September.

Climate change isn’t something we simply win or lose, then the game ends. As climate scientist Kate Marvel puts it, it’s more of a slope we slide down.

The sort of climate nihilism that the novelist Jonathan Franzen was pilloried for after his article in The New Yorker last week – that we’re doomed, so there’s no point doing anything – is the last thing we need right now. As we cross the threshold of 1°C of global warming, it’s still not too late.

Concerted, sustained action on behalf of all those who care about the future of the planet is what is needed. 20 September is the perfect time to show that’s where you stand, too. ❚ Alice Bell is co-director of climate charity 10:10.

Follow her on Twitter @alicebell 21 September 2019 | New Scientist | 21

Views Columnist This changes everything

Your job has been cancelled Gig workers in California will fight employers the old fashioned way – with laws. By Annalee Newitz

I

Annalee Newitz is a science journalist and author. Her novel Autonomous won the Lambda Literary Award and she is the co-host of the Hugo-nominated podcast Our Opinions Are Correct. You can follow her @annaleen and her website is techsploitation.com

Annalee’s week What I’m reading Gideon the Ninth by Tamsyn Muir, which features necromancers in space!

What I’m watching Tigers Are Not Afraid, a cinematic fairy tale about the ghosts of drug war victims in Mexico.

This column appears monthly. Up next week: James Wong 22 | New Scientist | 21 September 2019

GADO IMAGES / ALAMY STOCK PHOTO

What I’m working on Programming my coffee table.

T STARTED with a rumour.

“Don’t use the DoorDash app to tip your driver,” a friend told me. “The company steals tips.

You have to pay the driver directly, in cash.” Sure enough, a few days later the story broke: DoorDash, the food delivery app, was using tips to cover drivers’ guaranteed base rate of $10 per delivery.

If I tipped my driver $10 via the app, DoorDash would use that money to cover her base pay and she would get no tip.

If I tipped her in cash, she would get her $10 base from DoorDash, plus the tip she had earned.

Drivers were rightly incensed.

But there was nothing they could do. Like drivers at Uber and Lyft, these gig workers had been hired as independent contractors – and that meant no worker protections under US federal and state law.

Now that is about to change.

Thanks to a law that has just passed in California, known as Assembly Bill 5, many gig workers will be reclassified as employees, making them entitled to benefits, legal protections and the right to unionise.

This is what it sounds like when the future arrives. You were expecting disco, but you got punk rock. For over a decade, gig economy companies have been promising that they would launch us into an age of smooth, post-scarcity goodness, where everyone could do the work they wanted to do, when they felt like it.

All thanks to apps and algorithms that help workers find customers who want to pay them.

But when the rubber met the road, it turned out that the algorithms didn’t assign people enough work to survive. And then companies tried to squeeze even more money out of their gig workers, with things like DoorDash’s tip-keeping practice.

When workers complained, companies pointed to barely comprehensible “arbitration clauses” in the click-through employment agreements that their drivers had signed. These arbitration clauses meant all problems had to be resolved privately, between worker and company, without lawyers or union representatives.

Assembly Bill 5 has taken away those arbitration clauses too.

Uber has already vowed to fight the law. Its lawyers claim that the company’s primary enterprise is “technology”, not transportation.

Its drivers are therefore peripheral

“If I tipped my driver via the app, DoorDash would use that money for her pay and she would get no tip”

to its business, and not entitled to employee status. Uber’s representatives also claim that if drivers go full time, everything will suck because employees have to work set hours in limited locations.

These are mind-boggling assertions. First, Uber is literally nothing but drivers. Take them away, and the app is useless.

Second, the Uber app is incredibly sophisticated, capable of coordinating millions of requests and routes and fare changes.

But it is somehow too hard for Uber engineers to figure out how to assign flexible full-time hours to drivers in multiple locations?

Luckily, we can do more than merely pose snarky questions about Uber’s intentions. We can sue them. Under Assembly Bill 5, the state and cities have the right to sue businesses that incorrectly classify employees as contractors. That is what California is likely to do.

The whole scenario is a reminder that technological change doesn’t always lead us towards a more futuristic culture.

Sometimes, it leads us back to the Victorian era, when workers had no recourse to justice even when newfangled factory machines kept eating their arms and fingers. As we career into the next decade, this contradiction is likely to become more obvious.

And we are having to call on a very old-fashioned system, the law, to prevent the 21st century from turning into a Charles Dickens novel.

Gig work has spawned a new generation of union organisers and labour lawyers. And their movement is bleeding into the upper echelons of the tech industry, too. Google’s employees have staged walkouts to protest pay inequities, and Amazon is so worried about unionisation that it has created anti-labour educational videos for managers.

Even friendly crowdfunding site Kickstarter just fired two employees who were trying to organise a union. I’m pretty sure this isn’t the future that DoorDash and Uber’s funders were promised when they poured billions of dollars into gig apps.

Technology rarely leads to the social changes you might expect.

Even our shiny new phones and brilliant apps are mired in conflicts that go back centuries.

Maybe the best way to predict what’s next is to pay attention to what came before. ❚

SUBSCRIPTION OFFER

Subscribe today * from only $4.62 a week

- Free weekly print delivery to your door

As a New Scientist subscriber you also benefit exclusively from:

- The New Scientist app, giving you instant access anytime, anywhere, including - Current and back issues of New Scientist All issues of New Scientist: The Collection worth $14.99 (AUS) and $19.99 (NZ) each!

- Full access to newscientist.com with - Over 30 years of archive content - 100+ science talk videos - Early access to magazine features online

For easy online sign-up, visit newscientist.com/13565 Or call 1300 130 226 or +61 (0)2 8355 8923, quoting reference 13565 * A digital subscription package to New Scientist costs $5.39 a week, made payable by quarterly continuous payment methods

Our expeditions between Darwin and Singapore retrace the 17th century spice route pioneered by merchants who traded silks, cloves and nutmeg.

On our new expedition ship Coral Adventurer, cruise from island to island, witnessing the confluence of history, culture and wildlife unique to Indonesia.

Visit coastal villages where ironwood ships are built on the beach and textiles are woven on ancient looms, as they have been for generations.

See the endangered orangutans at Tanjung Puting National Park and the famed Komodo dragon on Rinca Island. Amidst the volcanic backdrop of Krakatoa, we will pause to pay tribute to Australia’s WWII history at the wreck of HMAS Perth, tragically torpedoed in the Battle of Sunda Strait. In between historic sights and cultural adventures there will be time to relax on white-sand beaches on little-visited islands and snorkel over vibrant coral gardens.

If you are curious about the world around you and freedom from the crowds is your idea of luxury, Coral Expeditions is your cruise line. For 34 years we have taken travellers into remote parts of the world with expert guidance and warm Australian hospitality.

Komodo Dragons & Krakatoa 18 Nights > Darwin – Singapore & vice versa > Departs 15th Jan & 2nd Feb 2020

call 1800 079 545 visit www.coralexpeditions.com email cruise@coralexpeditions.com *Terms & Conditions apply.

First Time Guests

Save $1,600pp Quote promo code FTI19A*

Views Your letters

Editor’s pick Several approaches to rescuing the Arctic Ocean 31 August, p 38 From Fred White, Nottingham, UK Just how big a cynic does it make me that when I read Rowan Hooper’s article on refreezing the Arctic, I couldn’t shake the conviction that certain politicians who are supposedly climate change sceptics may have links to corporations that can’t wait to get their snouts in the geoengineering trough?

From Luce Gilmore, Cambridge, UK Assuming that the ice does mostly melt, as seems likely, the Arctic could be the place that comes to the planet’s rescue. This may have happened before. During the early Eocene Epoch, the atmospheric carbon dioxide concentration peaked at more than 2000 parts per million – at present, it is around 400 ppm (and rising).

The Arctic Ocean had only one narrow channel to the other oceans. It probably had fresh water floating over saltwater.

Blooms of Azolla, freshwater ferns that fix nitrogen, grew here and lasted 800,000 years, bringing carbon dioxide concentrations down to 650 ppm. Dead Azolla sank to the anoxic depths, where its carbon still lies locked.

As geoengineering projects go, closing off the Arctic Ocean is quite a modest proposal. Of course, we would have to wait for the Arctic to warm a little more and for a floating freshwater cap to form before a second Azolla event could really take off. Thereafter, the process would be self-sustaining, and self-limiting once the ice returns.

From Jim McHardy, Clydebank, West Dunbartonshire, UK The melting of the Greenland ice sheet could be reduced by slowing the seaward movement of glaciers.

Moulins, holes that meltwater flows down, reduce friction between the base of the ice and the bedrock.

If a moulin is filled to the top, water pressure at the glacier base 26 | New Scientist | 21 September 2019

can be roughly equal to the pressure of the overlying ice. This results in the glacier almost floating away on the water at its base.

Bulldozing dams across the meltwater streams to divert water around a moulin and so reduce the flow under the glacier could be a quick fix. Or we could use large solar reflective sheets, supported by balloons, to cover moulins and refreeze water. Solar-powered propellers could keep the reflective sheets in position.

Money can’t buy you happiness or contentment 31 August, p 30 From Ros Groves, Watford, Hertfordshire, UK Apparently, the search for happiness is now a well-funded industry. Surely this calls into question whether spending so much time, money and, quite possibly, anxiety in its pursuit is counter-productive.

Instead, wouldn’t it be better to question what exactly happiness is? To me, it is experienced in response to a joyous event or achievement. It is fleeting, before a return to the baseline. Maintain

this state for too long and it will lose its magic. More superlative events will be needed to maintain this level of happiness, inflating everyday irritations to trauma.

Surely the answer lies in contentment? A neutral level of default temperament offers a greater ability to enjoy genuine happiness at all levels, to keep minor annoyances in perspective and to promote greater strength in dealing with misfortune.

Maybe grandchildren, not children, make us happier 24 August, p 12 From Brian Horton, West Launceston, Tasmania, Australia Alice Klein reports that having children makes us happier, but only when they leave home. This is consistent with a previous study (5 September 2015, p 40) showing that parents over 40 were happier than younger parents. I suggested (Letters, 26 September 2015) that it is grandchildren who make us happier. The latest study, concentrating on parents over 50, supports this, since children living at home are less likely to have their own children.

Please find a lower-impact kind of random curiosity 10 August, p 38 From Sam Edge, Ringwood, Hampshire, UK You suggest readers download a computer program to search for Mersenne primes in the background. Yet every week you report the looming peril of climate change and the need to change our behaviour to limit it.

Modern laptops and many desktop computers throttle back the processor speed and put their drives to sleep when idle. This significantly reduces power consumption. Installing software that keeps the processor loaded and that reads and writes data will prevent this – all to try to find mathematical objects for the sake of curiosity. How much extra carbon dioxide do you think would be released if every reader did as you suggest?

There are less energy-intensive ways to find rare things. You could catalogue birds, insects and plants for scientific surveys, for instance.

There are also distributed software projects seeking potentially beneficial things, such as the

Views From the archives

Neanderthals’ ears could indicate an aquatic past 24 August, p 17 From Malcolm Knight, Frizington, Cumbria, UK Neanderthals’ ears show signs of time in the water, as Ruby Prosser Scully reports. This seems to lend credence to the idea that humans led a semi-aquatic lifestyle, possibly before the split between Neanderthals and Homo sapiens.

Wading for fish and shellfish could have driven development of long hind limbs and an upright stance, with buoyancy giving support during the transition.

These changes could have given us the posture required to carry a large, heavy head.

A seafood diet provides highquality protein and lecithin for the development of a large brain.

Add to this the characteristics we share with sea mammals: salt tears, a diving reflex and blubber.

I would love to see this possible evolutionary path explored more.

Why can’t we use seawater to make hydrogen?

Letters, 20 July From Albert Lightfoot, Albury, New South Wales, Australia As Chris deSilva says, exporting hydrogen produced by electrolysis is like exporting water. But why use fresh water? Pure water is essentially a non-conductor, while seawater conducts electricity, aiding electrolysis. It may also have useful by-products, such as industrially useful rare earth metals, cobalt and lithium. If some desalination is necessary, use the same photovoltaic or wind-generated electricity that would be used for the electrolysis.

Lord make me admit my ignorance, but not yet

40 years ago, New Scientist highlighted research suggesting new uses for a familiar drug

17 August, p 42 From Mark Tester, Burtonsville, Maryland, US According to Anna Ijjas, Saint Augustine is said to have quipped that prior to creating the universe, God was preparing hell for those who pry into mysteries. What he in fact wrote in Confessions is: “I answer the man who says, ‘What did God do before he made heaven and earth?’ I do not give the answer that someone is said to have given, evading by a joke the force of the objection: ‘He was preparing hell for those prying into such deep subjects’… I would rather respond ‘I do not know’, concerning what I do not know, rather than say something for which a man inquiring about such profound matters is laughed at, while the one giving false answer is praised.”

And the award for most complex object goes to…

Letters, 10 August From Hillary Shaw, Newport, Shropshire, UK Guy Cox discusses whether our brains are the most complex objects in the universe, as they are parts of bodies, which are parts of societies… This implies some complexity metric: perhaps the bytes needed to describe an object divided by its volume. Otherwise, the universe must be the most complex object in the universe.

For the record ❚ The photo illustrating our note about the kakapo population hitting 200 was of a different parrot (31 August, p 21). ❚ We loathe vans (and other vehicles) spitting out nitrogen oxides (7 September, p 42).

Want to get in touch?

Send letters to New Scientist, 25 Bedford Street, London WC2E 9ES or letters@newscientist.com; see terms at newscientist.com/letters

D. HURST/ALAMY STOCK PHOTO

Folding@home effort to elucidate protein structures (8 November 2008, p 36).

WE HAVE known for a while there was something about the willow tree. Hippocrates, the “father of medicine”, recommended chewing willow bark as a remedy for pain and fever in the 5th century BC, as well as drinking tea brewed with it to relieve pain in childbirth.

In 1763, the clergyman Edward Stone from Chipping Norton, UK, wrote a letter to the president of the Royal Society describing his experiments, which showed that powdered willow bark helped treat the “agues”, or fevers, of people living in damp areas.

Willow bark, it turns out, is a rich source of salicylates, the class of compounds to which aspirin (acetylsalicylic acid) belongs. For more than a century, people have been taking aspirin in tablet form, and it is now one of the world’s most popped pills.

In our 20 September 1979 issue, we reported on some surprising new benefits of the drug. “The humble aspirin,” we wrote, “may turn out to be an important therapeutic tool in preventing blood clots in particularly sensitive people”.

The result came from a “large team of researchers from St Louis, Missouri. They gave the drug to a group of 19 patients undergoing blood dialysis over a period of five months”, we reported – more than halving the incidence of blood clots.

The team was careful not to claim too much, saying “aspirin may not necessarily prevent coronary thromboses”. But time has vindicated their work. Today, aspirin is routinely prescribed in low doses to people who have had a heart attack or stroke to protect them from having another.

More recently, aspirin has acquired yet another use.

Thanks to its anti-inflammatory properties, it seems it can help prevent some cancers. In 2014, a review led

by Jack Cuzick at Queen Mary University of London found that in the UK, more than 130,000 deaths from cancer would be avoided if all people aged 50 to 64 took a low-dose aspirin daily. The effects were greatest for bowel, stomach and oesophageal cancer, with smaller effects for prostate, breast and lung cancer.

“The second most important thing you can do to prevent cancer, after not smoking, is to take a low-dose aspirin,” Cuzick told New Scientist’s Chloe Lambert in May 2015. A wonder drug indeed – although as ever, check with your doctor first. Simon Ings To find more from the archives, visit newscientist.com/old-scientist

21 September 2019 | New Scientist | 27

Views Aperture

28 | New Scientist | 21 September 2019

Listen to Helen Scales explore the wonders of life in the deep ocean at New Scientist Live on 10 October newscientistlive.com

Inglorious mud Photographer Remi Masson Agency Nature Picture Library

EVEN fish can end up fighting over land. These land-dwelling great blue spotted mudskippers are facing off on the mudflats of Kyushu Island, Japan, their gaping mouths and raised dorsal fins a sign of aggression.

Mudskippers are highly territorial, with some species building mud walls to keep out trespassers. Walls also trap a pool of water in the fish’s territory, encouraging the growth of single-celled algae called diatoms, the main food for this species, Boleophthalmus pectinirostris.

If a mudskipper infringes on a neighbour’s territory, a fight may ensue. The 20-centimetre-long fish can leap 50 centimetres in the air during combat, or in mating displays, by propelling themselves with their pectoral fins.

As mudskippers have adapted to spend 90 per cent of their lives out of water, it is tempting to see them as a snapshot of our evolutionary past, when our ancestors first flapped onto land. They seem to have easily overcome many of the challenges for fish living on land. They move around using their fins, lay eggs in water-filled burrows and breathe through their gills and skin (although they have to keep their bodies moist).

This transition isn’t as difficult as it might seem, however: amphibious behaviour is reported in 33 families of fish, and many may have evolved independently.

The earliest tetrapods, which gave rise to amphibians, reptiles, birds and mammals, were more closely related to lungfish, which gulp air to help them survive in water with little dissolved oxygen. ❚ Sam Wong

21 September 2019 | New Scientist | 29

Views Culture

Waking up to anti-science In The Testaments, Margaret Atwood’s sequel to The Handmaid’s Tale, resistance is growing to the grim, puritanical world of Gilead, finds Donna Lu

Book

The Testaments

30 | New Scientist | 21 September 2019

“As seems characteristic of troubled political times, the line between fact and fiction is blurry”

Elisabeth Moss and Alexis Bledel star in the TV adaptation of The Handmaid’s Tale

HULU

“WHO would have thought that Gilead Studies – neglected for so many decades – would suddenly have gained so greatly in popularity?” muses a fictional future historian in The Testaments, Margaret Atwood’s sequel to The Handmaid’s Tale. It’s a tongue-incheek reflection of reality: some 34 years since The Handmaid’s Tale was published, the dystopian novel has had an unforeseen resurgence following a hit TV series, inspiring global protests about reproductive rights.

In the Republic of Gilead, a puritanical, theocratic society that has replaced the US, fertility rates are in free fall, after chemical and radiation exposure due to environmental damage.

Birth defects and stillbirths (“Unbabies”) are common, and childhood cancer is rising.

To redress this, the eponymous Handmaids are farmed out to powerful men whose wives can’t have children, for the purposes of procreating. (Officially, male infertility doesn’t exist.) Abortion is outlawed, and doctors who have carried out the procedure are executed.

Set 15 years later, The Testaments introduces a generation of girls who have grown up within Gilead, including one of the book’s three narrators, Agnes Jemima. They are taught they are “precious flowers” in a society where their worth is based on chastity and the ability to reproduce. Contrast this with a Canadian girl of the same generation, Daisy, for whom the piousness of Gilead is “weird as fuck”, the republic “a terrible,

ISOLDE OHLBAUM/LAIF/CAMERA PRESS

Margaret Atwood Chatto & Windus

terrible place, where women couldn’t have jobs or drive cars”.

Spoiler alert: Aunt Lydia, one of Gilead’s female architects, returns in a new guise. “Better to hurl rocks than to have them hurled at you. Or better for your chances of staying alive,” she reasons. Atwood read the “very cheery” diary of Hitler’s minister of propaganda, Joseph Goebbels, while writing the book. The nexus of all this drives the plot, which is both taut and gratifying, if tidy.

The extreme incarnations of the oppressive society Atwood created seemed divorced from the liberal democracies of 1985 when The Handmaid’s Tale was published.

But for Gilead’s antecedents, look elsewhere: combine Romania’s outlawing of birth control under

ET, where are you? Avi Loeb seeks answers at New Scientist Live, on the main stage on 12 October newscientistlive.com

Don’t miss

Real aliens Will ET look like us? Or be intelligent?

Simon Ings enjoys a tour of the exoplanets

Imagined Life James Trefil and Michael Summers Smithsonian

“IF YOU can imagine a world that is consistent with the laws of physics,” write planetary scientists James Trefil and Michael Summers, “then there’s a good chance it exists somewhere in our galaxy.”

The universe is mostly dark and empty, but the few pockets that are populated by matter are full of planets. Interstellar space is littered with hard-to-spot rogue worlds, ejected early in their solar system’s history, and they may outnumber orbiting planets two to one. Some experts put this figure at 1000 to one, which may explain why little green men have yet to land on the White House lawn.

So is our planet-cluttered galaxy full of life? Trefil and Summers are obviously primed to receive with open arms any visitors who happen by. In Imagined Life, their second book, they do a splendid job of explaining how tentative our thoughts on exobiology are.

Their first book, Exoplanets (2013), is already rather dated, such is the pace of the field.

In just 14 pages of Imagined Life, the authors outline the physical laws constraining the universe. They rattle through how to define life, and why spotting it is so difficult. Most of the molecules identified as a potential biomarker of life have a “nonbiological production mechanism”, they write.

They list environments in which life may have evolved, from water worlds to megaEarths (expect “normal fish… and stubby dinosaurs”). All this before the meat course: a tour, planet by imaginary planet, of otherworldly life and civilisation.

The authors want to believe in life that is “really not like us”, but have a hard time making it stick.

Carbon-based life itself may be pressing against unexpected limits. Of the 140 amino acids, only 22 are central to Earth’s biome; it may be that the mechanisms of inheritance must converge on a narrow set of possibilities, which may also set limits on alien biology.

The trick to finding life in odd places is to dig. Scientists are beginning to abandon the idea life must evolve and persist on the surface, the authors say, as they imagine an aquatic alien civilisation for whom a mission to the surface would be akin to a Mars mission for us.

I’m not sure I buy their assumption that life most likely breeds the kind of intelligence that manufactures technology.

Nothing in biology, or human history, suggests that. We may be a colossal oddity. Still, Imagined Life reminds me of my childhood books, full of artists’ impressions of oceans on Venus, only much, much better. ❚ Artists depict the search for life on planets beyond Earth

Listen

The Art of Innovation, on BBC Radio 4 from 16 September, explores the relationship between art and science over the past 250 years.

An accompanying exhibition at London’s Science Museum opens on 25 September.

Watch

Sea of Shadows, on limited UK release from 27 September, is a powerful documentary exposing the activities of Mexican drug cartels and Chinese traffickers in poaching activities that are driving the world’s smallest porpoise, the vaquita, to extinction.

Read

Altered Inheritance (Harvard). Bioethicist Françoise Baylis wonders what the unintended consequences might be of well-intentioned medical projects that harness CRISPR technology to edit the human genome.

21 September 2019 | New Scientist | 31

NATIONAL GEOGRAPHIC/ © DERBY MUSEUMS TRUST

Book

DAVID SHERMANN

Nicolae Ceaușescu with the monolithic theocracy of Iran, while Guardians escorting Gilead’s women remind us of Saudi Arabia’s male guardianship laws.

In troubled political times, the line between fact and fiction becomes blurry. Since the election of Donald Trump – an impetus for renewed interest in the book – some US states have passed laws restricting the right to abortion.

Meanwhile, fertility is dropping: in the past four decades, sperm counts in developed countries have fallen by more than half.

And in July, the US Environmental Protection Agency said it wouldn’t ban chlorpyrifos, a pesticide that has been linked to nervous system damage in young children.

Like its predecessor, The Testaments also draws on current events. School-sanctioned marches in Canada call to mind climate strikes, as young protesters hold signs reading: “GILEAD, CLIMATE SCIENCE DE-LIAR! GILEAD WANTS US TO FRY!” Atwood also wryly inverts the dynamics of US immigration politics. Gileadean refugees cross the Canadian border, smuggled via the Underground Femaleroad.

They become the refugees that Italy, Germany and even New Zealand are unwilling to accept.

At the heart of the novel is the power of narrative itself – of who gets to speak and to listen, of the ability of information to limit, control or expand a world.

“Knowledge is power, especially discreditable knowledge,” writes Aunt Lydia. “Loose lips sink ships,” several characters repeat. “Least said, soonest mended,” is another recurring adage.

A regime’s official story, argues The Testaments, rarely aligns with reality. Autocracies can be built on controlled narratives, but in the end, truth can still destroy. ❚

Views Culture The games column

Who wants a predictable life? Roguelike games are storytelling machines in which everyone’s experience is different. But they only work if the balance between order and randomness feels right, says Jacob Aron

In Rad, your character randomly mutates to gain new abilities

BANDAI NAMCO

Jacob Aron is New Scientist’s deputy news editor. He has been playing video games for 25 years, but still isn’t very good at them. Follow him on Twitter @jjaron

Game

Rad Double Fine PC, PlayStation 4, Xbox One and Nintendo Switch

Jacob also recommends...

Games

Spelunky Mossmouth PC and PlayStation 4

FTL: Faster Than Light Subset Games PC and iOS

32 | New Scientist | 21 September 2019

WHEN Apple launched the iPod Shuffle, people complained that its shuffling function didn’t work as advertised – songs by the same artist seemed to be clustering, so one David Bowie track, say, would swiftly be followed by another.

In fact, this kind of clustering is exactly what we would expect.

A random algorithm makes no effort to “remember” what has come before, so it makes for an unsatisfying listening experience.

In the end, Apple tweaked its software to avoid repetition.

“We’re making it less random to make it feel more random,” said the CEO at the time, Steve Jobs.

I was reminded of this playing Rad, a game set in a 1980s-tinged future following not one, but two apocalypses. As you explore a nuclear wasteland and vanquish enemies, your character randomly mutates to gain new abilities, such as an arm that shoots fire or a snake head that spits poison.

Rad is a roguelike, a genre named after the 1980 game Rogue, which sees players delve into a dungeon full of monsters and magic items (itself inspired by

the classic Dungeons & Dragons).

Rogue uses text characters to represent everything in the world, for example, the @ symbol is the player. Meanwhile, the dungeon is generated by an algorithm each time you start up, giving it the potential for huge variety.

I like to think of roguelikes as storytelling machines – ideally, your experience will be completely different from

“Roguelikes are not truly random – if they were, the game would be impossible to complete” someone else’s, making it fun to swap anecdotes with friends.

That said, like the altered version of the iPod Shuffle, roguelikes aren’t truly random – if they were, you’d end up with a game that was impossible to complete. In other words, a dash of order is key to making randomness enjoyable.

Unfortunately, Rad hasn’t quite got the balance right. Surprise and discovery are a huge part of the

roguelike genre, but with Rad, I found myself acquiring the same mutations again and again. Each time I died and started a new game, I had less of an urge to continue playing, as it felt like I wasn’t seeing anything novel, which doesn’t make for a great story.

Other roguelikes are well worth checking out, however. Spelunky, the king of modern roguelikes, is a near-perfect balance of order and chaos. The levels are never the same, but everything within the game is utterly predictable, allowing you to set up chains of actions such as throwing a bomb to blast a stone into the air, triggering a trap to kill a snake. You can’t help but laugh as you play.

For my taste, though, Spelunky is still a bit unforgiving as you start from scratch every time.

I prefer Rogue Legacy, which sees you play as a member of a long-running dynasty, each with their own quirks such as shortsightedness or vertigo. When you die, you get to keep certain items and upgrades from the previous run, allowing you to progress further into the game’s randomly generated castle. This persistence isn’t completely true to the roots of the roguelike genre, but it strikes the right balance for me.

Finally, some roguelikes abandon the dungeon trapping, but retain the randomness to generate unique experiences.

If you are a Star Trek fan, check out FTL: Faster Than Light, which has you command a spacecraft and crew. Hopping between star systems, you can live out your Captain Picard fantasies, managing power levels, or depressurising the ship to put out fires. Just don’t jettison the crew. ❚

SECOND EDITION OF BEING HUMAN

BEING HUMAN Take a step back from the everyday chores of being human to tackle the big – and small – questions about our nature, behaviour and existence.

Buy your copy from all good magazine retailers or digitally.

Find out more at newscientist.com/TheCollection

Features Cover story

What is consciousness?

A new idea about what consciousness is and why we have it reveals how we could recreate it, says neuroscientist Michael Graziano

OSKA

C

ONSCIOUSNESS is a slippery concept.

It isn’t just the stuff in your head.

It is the subjective experience of some of that stuff. When you stub your toe, your brain doesn’t merely process information and trigger a reaction: you have a feeling of pain. When you are happy, you experience joy. The ethereal nature of experience is the mystery at the heart of consciousness. How does the brain, a physical object, generate a non-physical essence?

This experience-ness explains why pinning down consciousness has been described as “the hard problem”. Subjective experience doesn’t exist in any physical dimension.

You can’t push it and measure a reaction force, scratch it and measure its hardness or put it on a scale and measure its weight.

Philosophers have described it as the “ghost in the machine”. Even scientific ideas about consciousness often have an aura of the metaphysical. Many scientists describe it as an illusion, while others see it as so fundamental that it doesn’t have an explanation. Always at the centre of the riddle lies its non-physicality.

But what if consciousness isn’t so mystical after all? Perhaps we have just been asking the wrong question. Instead of trying to grapple with the hard problem, my colleagues and I at Princeton University take a more down-to-earth approach. My background lies in the neuroscience of movement control, what you could call the robotics of the brain.

Drawing on that, I suggest that consciousness can be understood best from an engineering

34 | New Scientist | 21 September 2019

perspective. Far from being some sort of magical property, it is a tool of extraordinary power. It is a tool that can be engineered into machines. Our new approach shows how.

Because the normal methods of observation and measurement don’t quite apply, the study of consciousness has always sat uneasily in mainstream science. A few decades ago, The International Dictionary of Psychology described consciousness as “a fascinating but elusive phenomenon; it is impossible to specify what it is, what it does or why it evolved.

Nothing worth reading has ever been written about it.” Since then, consciousness has become an increasingly popular topic in science, generating numerous ideas and thousands of papers but very little agreement.

One approach searches for the neural correlates of consciousness: the minimal physical signature in the brain needed for subjective experience. There have been some interesting leads, but the hunt continues.

“Far from being some sort of magical property, consciousness is a tool of great, practical power”

Other researchers build on the insight that consciousness isn’t just a stimulus processed in the brain. Their higher-order thought theory proposes that the brain contains a system that re-represents the stimulus at a higher level with added self-information, which is how we become conscious of it. Exactly what that higher-order information is, what cognitive purpose it serves and where in the brain it is constructed are all debated – although some people associate it with the prefrontal cortex.

A particularly influential idea is known as global workspace theory. Here, information coming both from outside and within the brain competes for attention. Information that wins this competition becomes globally accessible by systems throughout the brain so that we become aware of it and are able to process it deeply. Also popular is the integrated information theory. It sees consciousness as an emergent property of complex systems and posits that the amount of consciousness in any system can be measured in units called phi. Phi is high in the human brain, but also present in everything from a hamburger to the universe, since everything contains at least some integrated information.

Then there is the idea that consciousness is an illusion. This is often misinterpreted. It doesn’t mean that consciousness doesn’t exist, or that we are fooled into thinking we have it.

Instead, it likens consciousness to the illusion created for the user of a human-computer interface and argues that the metaphysical properties we attribute to ourselves are >

21 September 2019 | New Scientist | 35

Understanding humans by building robots Hear Tony Prescott on brainy robotics at New Scientist Live newscientistlive.com

wrong. Researchers debate the exact source of these mistaken self-descriptions and the reason we seem to be mentally captive to them.

Engineering, and the science of robotics in particular, tells us that every good control device needs a model – a quick sketch – of the thing it is controlling. We already know from cognitive neuroscience that the brain constructs many internal models – bundles of information that represent items in the real world. These models are simplified descriptions, useful but not entirely accurate.

For example, the brain has a model of the body – called the body schema – to help control movement of the limbs. When someone loses an arm, the model of the arm can linger on in the brain so that people report feeling a ghostly, phantom limb. But the truth is, all of us have phantom limbs, because we all have internal models of our real limbs that merely become more obvious if the real limb is gone.

By the same engineering logic, the brain needs to model many aspects of itself to be able to monitor and control itself. It needs a kind of phantom brain. One part of this self-model may be particularly important for consciousness. Here’s why. Too much information flows through the brain at any moment for it all to be processed in equal depth. To handle that problem, the system evolved a way to focus its resources and shift that focus strategically from object to object: from a nearby object to a distant sound, or to an internal event such as an emotion or memory. Attention is the main way the brain seizes on information and processes it deeply.

To control its roving attention, the brain needs a model, which I call the attention schema.

A major advantage of this idea is that it gives a simple reason, straight from control engineering, for why the trait of consciousness would evolve in the first place.

Without the ability to monitor and regulate your attention, you would be unable to control your actions in the world. That makes the attention schema essential for survival. Consciousness, in this view, isn’t just smoke and mirrors, but a crucial piece of the engine. It probably co-evolved with the ability to focus attention, just as the arm schema co-evolved with the arm.

In which case, it would have originated as early as half a billion years ago.

Our attention schema theory explains why people think there is a hard problem of consciousness at all. Efficiency requires the quickest and dirtiest model possible, so the attention schema leaves aside all the little details of signals and neurons and synapses.

Instead, the brain describes a simplified version of itself, then reports this as a ghostly, nonphysical essence, a magical ability to mentally possess items. Introspection – or cognition accessing internal information – can never return any other answer. It is like a machine stuck in a logic loop. The attention schema is like a self-reflecting mirror: it is the brain’s representation of how the brain represents things, and is a specific example of higherorder thought. In this account, consciousness isn’t so much an illusion as a self-caricature.

36 | New Scientist | 21 September 2019

SOUTIRIS BOUGAS/EYEEM/GETTY

Ghostly essence

“In this account, consciousness isn’t so much an illusion as a self-caricature”

The big challenge will be giving a robot human-like sensory and emotional input

MANANA KVERNADZE/EYEEM/GETTY

Sometimes, the best way to understand a thing is to try to build it. According to this new idea we should be able to engineer human-like consciousness into a machine.

It would require just four ingredients: artificial attention, a model of that attention, the right range of content (information about things like senses and emotions) and a sophisticated search engine to access the internal models and talk about them.

The first component, attention, is one of the most basic processes in most nervous systems. It is nicely described by the global workspace theory. If you look at an object such as an apple, the brain signals related to the apple may grow in strength and consistency.

With sufficient attentional enhancement, these signals can reach a threshold where they achieve “ignition” and enter the global workspace. The visual information about the apple becomes available for systems around the brain, such as speech systems that allow you to talk about the apple, motor systems that allow you to reach for it, cognitive systems that allow you to make high-level decisions about it, and memory systems that allow you to store that moment for possible later use.

Scientists have already built artificial versions of attention, including at least a simple version of the global workspace.

But these machines show no indication of consciousness.

The second component that our conscious machine requires is an attention schema, the crucial internal model that describes attention in a general way, and in so doing informs the machine about consciousness. It depicts attention as an invisible property, a mind that can experience or take possession of items, something that in itself has no physical substance but still lurks privately inside an agent. Build that kind of attention schema, and you will have a machine that claims to be conscious in the same ways that people do.

The third component our machine needs is the vast stream of material that we associate with consciousness. Ironically, the hard problem – getting the machine to be conscious at all – may be the easy part, and giving the machine the range of material of which to be conscious may be the hard part. Efforts to build conscious content might begin with sensory input, especially vision, because so much is known about how sensory systems work in the brain and how they interact with attention. But a rich sensory consciousness on its own won’t be enough. Our machine should also be able to incorporate internal items such as abstract thought and emotion. Here the engineering

problem becomes really tricky. Little is known about the information content in the brain that lies behind abstract thought and emotion, or how they intersect with the mechanisms of attention. Sorting out how to build a machine with that content could take decades.

Talking my language The final component our conscious machine requires is a talking search engine. Strictly speaking, talking isn’t necessary for consciousness, but for most people the goal of artificial consciousness is a machine that has a human-like ability to speak and understand.

We want to have a good conversation with it.

The problem is deceptively hard. We already have digital assistants like Siri and Alexa but these are limited in their functions. You give them words, they search for words on the internet, and they then give you back more words. If you ask for the nearest restaurant, the digital assistant doesn’t know what a restaurant is, other than as a statistical clustering of words. In contrast, the human brain can translate speech into non-verbal information and back again. If someone asks you how the taste of a lemon compares with

“To engineer human-like consciousness into a machine would require four ingredients”

that of an orange, you translate the speech into taste information and compare the two remembered tastes, then translate back into words to give your answer. This easy back-andforth conversion between speech and many other information domains is challenging to do artificially. Our conscious machine would need to correlate information across every imaginable domain, a problem that hasn’t yet been solved in artificial intelligence.

Given all the promise and all the difficulties, just how close are we to conscious machines?

If the attention schema approach is correct, the first attempts at visual consciousness could be built with existing technology. But it will take a lot longer to give machines a human-like stream of consciousness. It will take time to build a conscious machine capable of seeing, hearing, tasting, touching, thinking abstract thoughts and feeling emotions, with a single integrated focus of attention to coordinate within and between all those domains, and able to talk about that full range of content. But I believe it will happen.

To me, though, the purpose of this thought experiment isn’t to advocate for conscious robots. The point is that consciousness itself can be understood. It isn’t an ethereal essence or an inexplicable mystery. The attention schema theory puts it in context and gives it a concrete role in adaptation and survival.

Instead of an ill-defined epiphenomenon, a fog extruded by the brain and floating between the ears, consciousness becomes a crucial component of the cognitive machine. ❚

Michael Graziano is a professor of psychology and neuroscience at Princeton University and author of Rethinking Consciousness 21 September 2019 | New Scientist | 37

Features Interview

“I want to break the cycle, not indoctrinate” Time hasn’t dimmed Richard Dawkins’s passion for evolution and a godless world, Graham Lawton discovers

You’ve written another book about God. Yes, Outgrowing God, which is for young people. Teenagers, let’s say – and young people up to about the age of 99 as well.

It covers a lot of familiar Dawkins territory, not just God but also evolution. Why did you feel that people need more on these topics?

I want to encourage people to think for 38 | New Scientist | 21 September 2019

themselves. I’ve always felt rather passionate about breaking the cycle as each generation passes on its superstitions to the next. If you ask people why they believe in the particular religion that they do, it’s almost always because that’s how they were brought up.

I’ve long wanted to try to break that cycle while being keen not to indoctrinate, because that’s of course what we criticise religious people for doing.

My experience of children of that age – admittedly, largely my own – is that they are uninterested in religion and don’t need persuading of the truth of evolution.

I’m glad to hear that. That cannot be true all over the world, however. It’s certainly not true in America, where unfortunately religion and anti-evolution have a real hold, and in the Islamic world.

Your new book spends a lot of time picking factual holes in the Bible and pointing out logical inconsistencies and absurdities. It’s good sport, but isn’t it a futile exercise?

It’s not futile to people who believe. So many people have a literalistic, Bible-based faith, and so they’re actually quite shocked to learn how little support there is for any Bible stories.

Many people in America are not aware that,

JUDE EDGINTON/CONTOUR BY GETTY IMAGES

F

EW scientists have acquired such a high public profile as Richard Dawkins – and maintained it amid such controversy.

His first book The Selfish Gene, published in 1976, launched him to fame as a populariser of evolutionary biology. Eight books and 30 years later, he wrote The God Delusion, which reinvented him as a ferocious advocate for atheism.

He chose his subjects well: during his writing career, evolution and religion have emerged as fronts in an increasingly vicious culture war between what he would characterise as the forces of darkness and superstition and those of enlightenment and reason.

Both lionised and demonised for his strident views, he is once again stepping into the fray, bringing his lifelong passions for evolution and secularism together in his 15th book, Outgrowing God: A beginner’s guide.

“I think we are all susceptible to a certain level of irrationality”

for example, virtually nothing in the Old Testament has any evidential support at all.

It’s not just Adam and Eve and Noah. There’s no evidence that there was a Jewish captivity in Egypt, for example, which is shocking to some people.

But we know that people believe in the Bible not because of the factual content of the stories, but because of a commitment to a group identity.

Probably yes, but a lot of people literally believe what they read in the Bible. It’s important to disabuse people of this, that the evidence for anything in the Bible is extremely flimsy.

In terms of the harms and abuses done in the name of religion, do you think that the world has become a better or worse place since you wrote The God Delusion?

It’s become a worse place, hasn’t it? I think and hope it is temporary. I think there is clearly an overall trend in the right direction, as you look over decades and centuries. Any trend like that is subject to reversals and I think we’re in a reversal at the moment. But I think it’s a blip.

If you look at the number of people who profess a religion in America and the rest of the world, it’s going down. The number of people who say they have no religion is now really substantial. It’s about 25 per cent, which is huge. It’s bigger than most other religious denominations. So that’s a very good sign.

However, it’s not entirely clear whether religion has given over to rationalism, or to a more vague, nonsensical new ageism.

That would be a pessimistic view.

Unfortunately, I think pessimism is in order.

There’s evidence that as people discard theologically correct views, they adopt other superstitions to replace them.

Yes, that could be true. So in a way, that’s why I think the second half of the book, the science part, is so important. I think we need to > 21 September 2019 | New Scientist | 39

Cruise Hawaii with Richard Dawkins Evolutionary biology, volcanoes and culture with Discovery Tours newscientist.com/tours

The Selfish Gene (1976) This influential bestseller popularised a gene-centred view of the world and introduced the concept of the meme

The Extended Phenotype (1982) Through examples such as a beaver’s dam, Dawkins illustrates the ways that genes interact with other genes and the wider environment of the organism

The Blind Watchmaker (1986) An eloquent frontal assault on the “what use is half an eye” argument that the complexity of living organisms are evidence of the work of a creator

Unweaving the Rainbow (1998) When Newton explained the origin of the rainbow’s colours, poet John Keats accused him of destroying its mystique. In this book, Darwin argues the opposite: that science enhances the wonder and beauty of the world

The God Delusion (2006) Dawkins on why a supernatural creator almost certainly doesn’t exist, and a belief in a personal god is a delusion

40 | New Scientist | 21 September 2019

really push the beauty of science, not just because it’s true but because it’s beautiful and an armoury against not just religion, but superstition generally.

That part of the book is less combative. For example, it doesn’t even mention the intelligent design movement or pick holes in its claims.

Yes, I simply put the positive case for evolution.

I want to persuade my readers that this is an elegant, beautiful idea that explains all the facts. That automatically undercuts intelligent design.

What about the wider culture war over evolution, particularly in the US? It’s still going on and there are constant little fracas, and it’s an important fight we have on our hands. There’s an anti-science culture in parts of America – I keep coming back to America – and evolution is on the front line.

We live in troubled times.

We do, yes.

I am interested in your views on why that might be. Things like post-truth politics, fake news, the triumph of gut feeling over facts – these are things you have spent a lifetime arguing against.

You must find it depressing.

Yes, it is depressing, but my views are not interesting. I think you’re right that we live in troubled times and I’m as troubled as the next person. But I’m not a sociologist. I’m not a psychologist. I would only be able to give an amateur opinion as a citizen, which is no more interesting than anybody else’s.

One of the things that frequently gets blamed for the mess we are in is social media, of which you are a prolific user.

I think that’s right. Ricky Gervais makes rather a good point when he says that the things people write on the walls of public lavatories you just ignore, and that’s what always used to happen. But now, instead of writing in lavatories, they tweet.

These are people who otherwise wouldn’t have a voice. No editor would publish what they write. They wouldn’t get a letter published in the newspaper. In the old days, what they would do is write on walls. Now, they tweet.

Have you ever considered quitting Twitter?

All it ever seems to do is polarise and inflame...

It does. I mean, if you look at replies, that’s what you get. But then if you look at the number of people who retweet and the number of people who like, that can be very substantial.

CHRIS MCANDREW/CAMERAPRESS

GREATEST HITS

Some of your tweets have led to you being called Islamophobic.

I know. What I’ve said is that Muslims are not culprits, but the biggest casualties of Islam. They’re the ones who suffer most from Islam, so I’m anti-Islam but I’m definitely not anti-Muslim.

People have also criticised you for subjecting Islam to special criticism.

Not at all. If you look at The God Delusion or Outgrowing God, Islam is scarcely mentioned.

I could more fairly be accused of attacking Christianity and not attacking Islam enough.

You’ve described the word Islamophobia as “otiose”. Could you explain what you mean?

Unnecessary and actually pernicious, because it gives an entirely wrong impression. There’s no word “Christianophobe”. But we shouldn’t be phobic about people. We should be mistrustful of ideologies where they have pernicious effects, which I think virtually all religions do.

PROFILE Richard Dawkins is emeritus professor of evolutionary biology at the University of Oxford.

He was professor of public understanding of science from 1995 to 2008. He tweets @RichardDawkins

I write about the environment and I have developed quite a jaundiced view of humanity as a result. But you strike me as somebody who is quite optimistic that reason and science will prevail.

Am I? I’m not sure. There’s some ground for believing that although there are problems, science will solve them. Science’s track record is encouraging, but such optimism as I have is cautious.

Do you feel like your books have helped to advance the causes of rationality?

I can’t possibly tell. I’m glad I’ve written all the books I have, and I’m glad they’re all in print and selling well. I get numerous letters from people who say that they went into science because they read one of my books. I find that hugely encouraging, hugely gratifying.

Do people say that to you about atheism too?

Yes, they do.

To return to God, your new book discusses the evolutionary psychology of religion.

As an evolutionary biologist, do you buy the idea that human brains are naturally receptive to religious ideas?

I think that’s got to be true, which of course doesn’t mean that they’re right to do so.

We need some kind of explanation for the fact that religion is such a ubiquitous phenomenon all over the world.

Another chapter in your book looks at progress in moral issues such as gender and racial equality, and you present a very upbeat picture. Do you worry that progress has gone into reverse?

No. It’s important to take the long view. I think there’s absolutely no doubt that we’re getting better as the centuries go by. The moral standards of a 21st century person are significantly different from those of a 20th century person.

For all that we have reversals, we have at the same time a very strong movement in favour of gay rights, in favour of all sorts of other things which would once have been inconceivable. During my lifetime, you could go to prison for homosexual activities in private.

If you were to project into the future, what current cultural norms will be seen as morally indefensible?

Almost a no-brainer: the treatment of non-human animals.

“We really need to push the beauty of science”

Are you vegetarian?

I’m trying to be. I’m vegetarian at home!

I want everybody to do it. That’s another thing moving in the right direction.

You have never written in detail about the environmental crisis. That strikes me as a debate you could usefully contribute to, because it’s essentially a failure of rationality and truth.

Yes, it is. I can’t deny its huge importance, but I haven’t written much about it. It hasn’t been my field and so, at present, I’d be an amateur.

One conclusion of that research is that humans are deeply irrational and that belief in the supernatural is etched into our brains.

Do you accept that?

Well it’s not universally true, clearly.

There are plenty of highly rational people about: people who are not religious, who are not superstitious and who do maintain a sceptical attitude towards such things.

Although, even those of us who think we’re rational sometimes get things wrong.

We are susceptible to certain irrationalities.

Are there any that you’ll admit to?

I think that if I were locked in a notorious haunted house at night, I might be frightened. I’ve never tried it. But I think we’re all of us susceptible to a certain level of irrationality. ❚

Graham Lawton (@GrahamLawton) is a staff writer at New Scientist

21 September 2019 | New Scientist | 41

PHOTO ESSAY

The sunken rainforest Deep in the Amazon, hydroelectric dams are drowning hundreds of thousands of trees, transforming forests into sources of greenhouse gases. Daniel Grossman reports. Photographs by Dado Galdieri

42 | New Scientist | 21 September 2019

PHOTO ESSAY

I

N BALBINA, a small town in the heart of the Brazilian Amazon, the shoreline of a vast reservoir sparkles blue and a mild wind ruffles the water, lifting small whitecaps. Within a few months, fire will devastate vaste swathes of the forest, some not far from here, but the story I’ve come to investigate lies just below the water’s surface, where millions of trees have been drowned by a hydroelectric dam blocking the Uatumã river. The submerged jungle is no longer sucking carbon dioxide out of the atmosphere. Instead, the rotting corpses of once-magnificent trees are belching out yet more greenhouse gases.

No wonder the Balbina dam is known by experts as “the worst hydroelectric power plant in the world”. And yet its environmental impact is worse than previously thought, as I discovered when I visited the region earlier this year to spend time with climate researchers.

Their findings suggest that any dam built in tropical lowlands could be exacerbating the climate crisis, which is particularly alarming now that Brazil’s president Jair Bolsonaro has promised to extract more of the Amazon’s resources, including hydroelectric power.

Completed in 1989, the Balbina dam was controversial from the start. Its construction ensured that an area substantially larger than Greater London was flooded, engulfing territory that belonged to indigenous groups previously decimated by disease and violent confrontations with settlers.

The Brazilian government claimed the project would modernise the Amazon. But the dam never achieved its advertised capacity, and over the past decade whatever green credentials it had have been discredited.

Hydroelectric power is widely considered a good way to reduce greenhouse gas emissions while satisfying our ever-increasing demand for power. The most recent study produced for the Intergovernmental Panel on Climate Change (IPCC) on this topic, released in 2012, reported that, taking into account construction and

operation, hydroelectric power produces only half a per cent to three per cent of the warming of fossil-fuel power plants that burn coal, oil or natural gas.

That is true for some dams, such as those built in relatively cool, dry places with relatively little vegetation, which rots and turns into greenhouse gases.

But the IPCC report ignored dams built in lowland tropical forests, where luxuriant jungle produces an unusually large amount of emissions.

One of the first people I met when I travelled to Brazil was Philip Fearnside, a biologist at the National Institute of Amazon Research, known as INPA, in Manaus. He has spent the past 25 years arguing that hydroelectric dams in tropical lowlands are a climate disaster.

He cites two reasons. First, tropical lowland forests are highly productive and so contain more carbon than other areas, which means they release more when they die. Second, in hotter climates microbes that digest organic matter grow better and so produce more greenhouse gases. There are two types of microbes that digest the dead trees: one group operates in the oxygenfree conditions at the bottom of the reservoir and produces methane while the other, which lives in oxygen-rich water close to the surface, produces >

Top: Part of the massive reservoir created by the Balbina dam Bottom: Philip Fearnside in his basement office in Manaus Far left: Some 300 kilometres downstream from the dam, a rare Igapó forest has been flooded.

As its trees rot, they give off huge amounts of greenhouse gases

21 September 2019 | New Scientist | 43

PHOTO ESSAY

CO2. In both cases, growth is promoted by higher temperatures.

Fearnside says that the increased methane created in tropical dams is especially problematic. Although it is relatively short lived in air, methane warms the atmosphere much more than CO2. According to the IPCC, over 20 years, each gram of methane has the same heating effect as 86 grams of CO2.

So why did the IPCC reports give tropical dams a clean bill of health?

“A lot of the authors were from big hydroelectric companies,” Fearnside says. William Moomaw at Tufts University in Massachusetts, lead author of the methodology study on which the 2012 IPCC report was based, says the body did “drop the ball,” by lumping tropical dams with all dams as if there is no distinction. But he insists that was due to inattention, not nefarious motives. “The IPCC is dominated by people from the temperate world,” says Moomaw.

In any case, a clear-eyed assessment of tropical dams is now more critical than ever. Most of the hydroelectric plants being planned are in the tropics, primarily in lowland forests. Nearly 150 large dams are slated in the Amazon basin alone, with another 72 planned in Laos and 50 in Cambodia. We aren’t going to restrain global warming if we build these dams based on false assumptions, says Fearnside.

One of those assumptions was that the methane generated in the reservoir is forever trapped, held down by the mass of water above. But Fearnside and his colleagues weren’t convinced. In the early 2000s Bruce Forsberg, also at INPA, and Alexandre Kemenes, then a graduate student of Forsberg’s, put this to the test. They realised the turbine water intake at Balbina is several metres below the surface, right where most of the methane is held. They thought the gas could be released into the air where the water disgorged and the pressure dropped. “Like opening a bottle of Coca-Cola,” says Forsberg.

Sure enough, when Kemenes invented a novel way to sample the water exiting the turbines for methane, the researchers detected significant amounts of the stuff.

44 | New Scientist | 21 September 2019

Above: Emissions from dead and dying trees in an Igapó forest fuel global warming Right: Brazil’s president Jair Bolsonaro has promised to increase exploitation of the Amazon’s resources, including through hydroelectric power Far right: Brazil’s demand for electricity has soared in recent years, driven by the rise of the middle class in cities like Rio de Janeiro

Extrapolating, they were able to show that the reservoir at the Balbina dam is releasing 39,000 tonnes of methane every year. This more than doubles the amount attributable to the dam compared with previous estimates.

The research shows that if you include methane and CO2, Balbina is nearly 10 times as bad for the environment as a coal-fired power station producing the same amount of electricity.

The news got even worse earlier this year when another research team reported that the dam is creating even more CO2 and methane downstream of the floodgates. To see for myself, I joined Jochen Schöngart, another INPA biologist, in a fishing boat.

Halfway between Balbina and the point where the Uatumã river joins the Amazon river, Schöngart stared gloomily across the gunwale. Our pilot

cut the engine and we glided silently through a dead forest, skeletal branches poking above the water.

This eerie graveyard was once a stand of rare shoreline trees, known as an Igapó forest. Its trees are adapted to sporadic flooding, the result of rains changing the water level each year.

But the construction of the dam disrupted the river’s natural rhythms.

Balbina’s technicians deal with the annual three-month pulse of high water by adjusting outflow to store this extra water for release during the rest of the year, smoothing out the amount of electricity produced. In years gone by, the water level of the river fluctuated a lot more between wet and dry seasons than it does now.

Where Schöngart has brought me, the average difference in water level between these seasons has been

Shaun Quegan will talk about mapping forests from space on the Earth stage at New Scientist Live on 10 October newscientistlive.com

significantly reduced. During the dry season the water is on average 1 metre higher than before the dam was built.

Schöngart thinks this higher water prevented tree roots from ever drying out, killing the forest. To confirm it, he and his team looked at growth rings inside 17 dead trees to see when the forest started failing. The results showed that the first trees began dying a year or so after Balbina started raising the river’s dry season level.

Every tree at the lowest elevation along the previous shoreline has since died.

Schöngart and his team also used satellite radar images to estimate the scale of tree mortality. They found that the dam has killed hundreds of thousands of Igapó trees, which had previously locked up roughly 130,000 tonnes of carbon. It isn’t yet clear how quickly the carbon from this dead and

rotting forest will be released, but it only adds to the case that the Balbina dam is even more environmentally damaging than anyone thought.

The problem is, demand for energy is growing. Hydroelectric dams provide 80 per cent of Brazil’s electricity, and president Bolsonaro has promised to build more. That will be “disastrous for the environment and for local people”, says Fearnside.

Even insiders from Brazil’s hydroelectric industry agree that the Balbina dam produces too much greenhouse gas. Luiz Pinguelli Rosa, former president of Electrobras, Brazil’s largest electricity company, admits that “Balbina is very bad”. But he insists that it is an outlier.

Forsberg begs to differ. More than a decade ago, he and Kemenes demonstrated that three other dams

in the Amazon also give off two to four times as much CO2 as an equivalent coal-fired power plant. “Almost all of these lowland tropical dams emit more greenhouse gases per megawatt than a thermoelectric plant burning dirty coal,” he says.

As Bolsonaro plots to further exploit the Amazon to fuel Brazil’s economic development, one thing is abundantly clear. “The solution is to not build more dams,” says Fearnside. ❚

Daniel Grossman (left) is a reporter based in Massachusetts. Dado Galdieri is a photographer based in Rio de Janeiro. Their trip was supported by the Pulitzer Centre

21 September 2019 | New Scientist | 45

Recruitment Assistant Professor of Chemistry The University of Chicago: Physical Sciences Division: Department of Chemistry

newscientistjobs.com Recruitment advertising Email nssales@newscientist.com

Location Chicago, Illinois Description The Department of Chemistry at The University of Chicago invites applications for the position of Assistant Professor of Chemistry in all areas of chemistry.

Applicants must apply online at apply.interfolio.com/66199 and upload a cover letter, a curriculum vitae with a list of publications, a succinct outline of research plans and a one page teaching statement. In your cover letter, please specify one sub-discipline that best represents your research interests (inorganic, materials, organic, physical, theoretical or chemical biology). In addition, three reference letters are required.

8\HSPĂ„JH[PVUZ At the time of hire the successful candidate must have completed all YLX\PYLTLU[Z MVY H 7O + PU *OLTPZ[Y` VY H YLSH[LK Ă„LSK 1VPU[ HWWVPU[TLU[Z ^P[O other departments are possible.

Application Instructions Review of applications will begin on October 07, 2019 and will continue until all WVZP[PVUZ HYL Ă&#x201E;SSLK Apply to: apply.interfolio.com/66199 Equal Employment Opportunity Statement ;OL <UP]LYZP[` VM *OPJHNV PZ HU (É&#x2030;YTH[P]L (J[PVU ,X\HS 6WWVY[\UP[` +PZHISLK =L[LYHUZ ,TWSV`LY HUK KVLZ UV[ KPZJYPTPUH[L VU [OL IHZPZ VM YHJL JVSVY religion, sex, sexual orientation, gender identity, national or ethnic origin, age, status as an individual with a disability, protected veteran status, genetic information, or other protected classes under the law. For additional information please see the Universityâ&#x20AC;&#x2122;s Notice of Nondiscrimination.

1VI ZLLRLYZ PU ULLK VM H YLHZVUHISL HJJVTTVKH[PVU [V JVTWSL[L [OL application process should call 773-702-1032 or email equalopportunity@ uchicago.edu with their request.

Bring your career to life Sign up, create your own job alerts and discover the latest opportunities in life sciences at

newscientistjobs.com

Research Fellow Research Experience required in Immunology, Bioengineering, Immunotherapy, T cell Biology, Antibody Engineering or T cell Receptors. With the research experience, candidate should be well-versed in various lab experiences including tissue culture, cell-based assays measuring phenotypes of various cell subsets, F\WRWR[LFLW\ DQG SUROLIHUDWLRQ Ë&#x160;RZ F\WRPHWU\ DQDO\VHV It could be also helpful if candidate is familiar with gene editing, molecular biology techniques, western blot analysis (immune-histochemistry, immunoprecipitations and immunoblotting), transfections, RNA/ '1$ H[WUDFWLRQV 3&5 SXULË&#x2030;FDWLRQ RI SODVPLGV DQG general lab organization/ordering as well as lab safety LVVXHV ([SHUWLVH LQ HYDOXDWLRQ RI GUXJ HIË&#x2030;FDF\ VWXGLHV LQ animal models could be also helpful.

Education: Ph.D with experience.

Dana-Farber Cancer Institute is an equal opportunity HPSOR\HU DQG DIË&#x2030;UPV WKH ULJKW RI HYHU\ TXDOLË&#x2030;HG applicant to receive consideration for employment without regard to race, color, religion, sex, gender identity or expression, national origin, sexual orientation, genetic information, disability, age, ancestry, military service, protected veteran status, or other groups as protected by law.

@science_jobs

#sciencejobs

46 | New Scientist | 21 September 2019

Apply Here: http://www.Click2apply.net/yrvrqt4zkc6jf6yk

newscientistjobs.com

Scientific Writer You will excel at this role if you have: · PhD/MD (Pharmacology) OR PhD (Life Sciences) OR MBBS/MD · Publication experience, preferably as first author, in reputed journals · Clear, concise, scientific style of writing, with a high level of attention to detail and superior English-language skills · Basic knowledge of biostatistics · Excellent comprehension skills and ability to interpret scientific data · Ability to multi-task and work under tight timelines You will be the star you are meant to be if you have: · Knowledge of clinical research and drug development · PhD in a subject area related to medicine · Excellent literature reviewing and evaluation capabilities As part of our exciting team your responsibilities will include: · You will use scientific expertise to develop high-quality, publication-ready scientific documents (manuscripts, posters, abstracts, slide kits, short communications, etc.) according to client needs under the expert guidance of the Scientific Team Lead · You will act as a document specialist, provide intellectual input across document types, and contribute to making cutting-edge research accessible to specific audiences as appropriate, by maintaining current awareness of developments across therapeutic areas or disciplines. · You will work with international pharmaceutical clients and liaise with internal and external stakeholders, including authors and key opinion leaders on critical therapeutic area issues · Effectively and proactively communicate with team members, authors/faculty, clients, and vendors · Attend workshops/seminars/Trainings to hone your skills and contribute to organizational objectives.

What’s in it for you: · Global exposure: We work with the top 10 Pharmaceutical companies across the globe. So you can be assured that you get the best experience in terms of the profile you handle. · Culture & Team: We never stop recruiting the best people because without an amazing team nothing is possible. People at CACTUS are awesome to work with, driven, smart and know how to get things done like nobody else. · Learn & Grow: Our goal is to keep you as long possible and help you build a career with us. We do this by creating an environment where you will grow both personally and professionally. · Satisfaction & Recognition: With some of the biggest names across the globe as existing clients, doors will open and conversations will flow. You will see the results of your efforts translate into maximum impact. With a competitive salary and our recognition programmes, you will be rewarded for your success.

CACTUS was ranked #18 in the top 25 Best Small & Medium Workplaces in Asia – 2018, a study conducted by Great Place to Work® Institute CACTUS was also ranked 1st as Best Organization for Women Empowerment / Women Talent Development in 2019 “At CACTUS, we believe we put our best work forward when our employees bring together ideas that are diverse in thought. We are proud to be an equal opportunity workplace and are committed to equal employment opportunity regardless of race, color, religion, national origin, age, sex, marital status, ancestry, physical or mental disability, genetic information, veteran status, gender identity or expression, sexual orientation, or any other characteristic protected by applicable national, state or local law. In addition, CACTUS will provide reasonable accommodations for qualified individuals with disabilities. If you have a disability or special need, we would like to know how we can better accommodate you.”

APPLY NOW: To apply, please email freelancepositions@cactusglobal.com with your updated resume.

Fellowships for Postdoctoral Scholars "1_oѲ-uv_brv -u; -Â&#x2C6;-bѲ-0Ѳ; |o m;Â&#x2030; ou u;1;m| 7o1|ou-Ѳ ]u-7Â&#x2020;-|;v bm 7bÂ&#x2C6;;uv; -u;-v o= u;v;-u1_ĸ rrѲb1-࢟omv Â&#x2030;bѲѲ 0; accepted from doctoral recipients with research interests associated with the following: Departments - Applicants who wish to conduct research on topics of general interest to one or more of the departments are encouraged to apply. Interdepartmental research, including with the Marine Policy Center, is also encouraged. The Departments are: Â&#x192; Applied Ocean Physics & Engineering Â&#x192; Biology Â&#x192; Geology & Geophysics Â&#x192; Marine Chemistry & Geochemistry Â&#x192; Physical Oceanography

A joint USGS/WHOI aaward will be given to a postdoc whose research is in an area of common interest between USGS and WHOI Scientific Staff. The individual will interact with both USGS and WHOI based advisors on their research.

$_; 1;-m oÂ&#x201A;ol ";bvlo]u-r_ mv|uÂ&#x2020;l;m| Center (OBSIC) will award a fellowship for research on the earthâ&#x20AC;&#x2122;s internal structure and its dynamic processes Â&#x2020;vbm] v;-Yoou v;bvlb1 l;-vÂ&#x2020;u;l;m|vÄş !;v;-u1_ -u;-v bm1Ń´Â&#x2020;7;Äš v;-Yoou v;bvlb1 bmv|uÂ&#x2020;l;m|-ŕŚ&#x17E;omġ bm1Ń´Â&#x2020;7bm] |_; 7;Â&#x2C6;;Ń´orl;m| -m7Ĺ&#x2020;ou -rrŃ´b1-ŕŚ&#x17E;om o= m;Â&#x2030; v;mvouvĸ ;-u|_ v|uÂ&#x2020;1|Â&#x2020;u; Â&#x2030;b|_ -m ;lr_-vbv om Â&#x2020;vbm] o1;-mĹ&#x160;0oÂ&#x201A;ol seismograph data, including the development and/ ou -rrŃ´b1-ŕŚ&#x17E;om o= m;Â&#x2030; -m-Ń´Â&#x2039;ŕŚ&#x17E;1-Ń´ l;|_o7oŃ´o]b;vĸ ;-u|_tÂ&#x2020;-h;Ĺ&#x160;u;Ń´-|;7 ruo1;vv;v Â&#x2020;vbm] v;-Yoou v;bvloŃ´o]Â&#x2039; -m7Ĺ&#x2020;ou ];o7;vÂ&#x2039;ĸ |_; bm|;urŃ´-Â&#x2039; 0;|Â&#x2030;;;m v;-Yoou v;bvlb1 measurements and oceanographic ruo1;vv;vĸ -m7 o|_;u ruof;1|v within this broad scope. Award recipients may be advised by v1b;mŕŚ&#x17E;C1 v|-@ Â&#x2030;b|_bm |_; CÂ&#x2C6;; Departments as well as the USGS, or a 1ol0bm-ŕŚ&#x17E;om thereof.

!;1brb;m|v o= -Â&#x2030;-u7v -u; v;Ń´;1|;7 1olr;ŕŚ&#x17E;ŕŚ&#x17E;Â&#x2C6;;Ń´Â&#x2039;ġ Â&#x2030;b|_ primary emphasis placed on research promise. Scholarships -u; -Â&#x2030;-u7;7 =ou Ć?ŃśĹ&#x160;lom|_ -rrobm|l;m|v Â&#x2030;b|_ - vŕŚ&#x17E;r;m7 of $61,200 per year, a health and welfare allowance and a lo7;v| u;v;-u1_ 0Â&#x2020;7];|Äş !;1brb;m|v -u; ;m1oÂ&#x2020;u-];7 |o rÂ&#x2020;uvÂ&#x2020;; |_;bu oÂ&#x2030;m u;v;-u1_ bm|;u;v| bm -vvo1b-ŕŚ&#x17E;om Â&#x2030;b|_ u;vb7;m| "1b;mŕŚ&#x17E;C1 -m7 ";mbou $;1_mb1-Ń´ "|-@Äş ollÂ&#x2020;mb1-ŕŚ&#x17E;om Â&#x2030;b|_ ro|;mŕŚ&#x17E;-Ń´ ) -7Â&#x2C6;bvouv rubou |o vÂ&#x2020;0lbমm] -m -rrŃ´b1-ŕŚ&#x17E;om is encouraged. olrŃ´;|;7 -rrŃ´b1-ŕŚ&#x17E;omv lÂ&#x2020;v| 0; u;1;bÂ&#x2C6;;7 0Â&#x2039; 1|o0;u Ć?Ć&#x201D;ġ Ć&#x2018;Ć?Ć?Ć&#x2013; for the 2020/2021 appointments. Awards Â&#x2030;bŃ´Ń´ 0; -mmoÂ&#x2020;m1;7 bm ;1;l0;uÄş !;1brb;m|v o= -Â&#x2030;-u7v 1-m bmbŕŚ&#x17E;-|; |_;bu v|Â&#x2020;7Â&#x2039; -m7 u;v;-u1_ r;ubo7 -| |_; mvŕŚ&#x17E;|Â&#x2020;ŕŚ&#x17E;om -mÂ&#x2039; ŕŚ&#x17E;l; -[;u -mÂ&#x2020;-uÂ&#x2039; Ć?ġ Ć&#x2018;Ć?Ć&#x2018;Ć? -m7 0;=ou; ;1;l0;u Ć?ġ Ć&#x2018;Ć?Ć&#x2018;Ć?Äş Â&#x2020;u|_;u bm=oul-ŕŚ&#x17E;om -0oÂ&#x2020;| |_; "1_oŃ´-uv_brv -m7 -rrŃ´b1-ŕŚ&#x17E;om forms as well as links to the individual Departments and their research themes may be obtained through the Academic uo]u-lv v;1ŕŚ&#x17E;om o= |_; ) Â&#x2030;;0 r-];v -|Äš

Â&#x2030;Â&#x2030;Â&#x2030;ÄşÂ&#x2030;_obÄş;7Â&#x2020;Ĺ&#x2020;rov|7o1|ou-Ń´ tÂ&#x2020;-Ń´ rrou|Â&#x2020;mb|Â&#x2039;Ĺ&#x2020; Lul-ŕŚ&#x17E;Â&#x2C6;; 1ŕŚ&#x17E;om lrŃ´oÂ&#x2039;;u

The back pages Puzzles Cryptic crossword, an egg puzzle and the quick quiz p52

Feedback Elongated eels and naming names: the week in weird p53

Almost the last word Lightning effects and biscuit/cake duality: readers respond p54

Picture of the week Our pick of your future-themed photos p53

The Q&A Randall Munroe on the creative use of science p56

Stargazing at home Week 1

Earth’s celestial moment It’s almost the September equinox, making this the perfect time to kick off our exploration of the heavens with Abigail Beall

Abigail Beall is a science writer in Leeds, UK. This series is based on her book The Art of Urban Astronomy @abbybeall

What you need Cardboard Two balls Wire Sticks Glue and scissors

For next week A clear night sky

Next in our 7-week series 1 Model the equinox 2 Find the North Star and Southern Cross Learn to navigate by the stars 3 Test your area’s light pollution 4 Identify the craters of the moon 5 Orion and Sirius: how to star-hop 6 Planet spotting: Mars, Mercury and Uranus 7 Taurus and the zodiacal constellations

EVER looked up at the night sky in wonder? Ever wished you could spot Mars or navigate by the stars?

Then our new astronomy series is for you, wherever you live in the world and even if you are in a lightpolluted city. Better still, no special equipment is required.

Crucial to making sense of the night sky is understanding Earth’s movement around the sun. As an equinox falls on 23 September, I’m going to kick off the series with a simple model to explain what it is.

There are two equinoxes in the year; they are the points when the lengths of day and night are nearly equal over the world. The one in September is when the southern hemisphere begins to tilt slightly more towards the sun and spring begins. In the north, it marks the start of autumn, or fall.

The equinox isn’t a day-long event, however. It is the exact moment when the sun crosses the plane of Earth’s equator, which varies according to your latitude.

The model we are making won’t be to scale, but that’s OK for our purposes. Start with a circular piece of card. Cut another piece into a rectangle the same length as the circle’s radius, like the one in the picture. Then pierce a hole at one end of your rectangle and at the centre of your circle and push a stick through both. Glue a ball on top to represent the sun.

Next, bend a piece of wire to 23.5° – that is the angle of Earth’s axis of rotation – and stick it into the other end of your rectangle.

Pierce the poles of your “Earth” ball and stick the wire through.

23.5

0

ANGLE OF EARTH'S TILT

PRECESSION EARTH SIDE-ON TO SUN AT EQUINOX

Stargazing at home online Projects will be posted online each week at newscientist.com/maker Email: maker@newscientist.com

Now move your Earth around the sun, keeping your polar wire pointing in the same direction at all times. You’ll come to a point at which the northern hemisphere tilts towards the sun. This is the June solstice, marking the northern summer.

As you move your Earth further round its orbit, it will reach a point where both hemispheres face the sun the same amount – this is where we are now, the September equinox. When the south pole tilts most to the sun, you have reached the December solstice, and the March equinox comes when both sides are equal again.

The tilt of Earth is also moving,

in a process called precession. To simulate this, hold the end of the wire protruding from Earth’s north pole and make it trace a small circle (see picture). This rotation takes 25,772 years to complete, meaning that in around 13,000 years’ time, summer in the northern hemisphere will happen when it currently experiences winter.

It also means the North Star will change, because the north pole will no longer be pointing in the same direction. Instead of Polaris, the bright star Vega will be the north star. Which brings us to next week, when we’ll be using what we have learned to find the North Star and the Southern Cross. ❚ 21 September 2019 | New Scientist | 51

The back pages Puzzles Quick quiz #21

Cryptic crossword #15 Set by Wingding

ACROSS 1 Express disapproval about British leader putting his country before Europe (6) 4 Headless rodents grab physiotherapistâ&#x20AC;&#x2122;s tool (3,3) 9 Microbiologist finding sticky substance by old city (7) 10 Boy eating last of supper with zero fat (5) 11 Audibly put together joint when necessary (2,3) 12 Vehiclesâ&#x20AC;&#x2122; gas emission reversed by first generation, adding carbon (7) 13 Large animal at university â&#x20AC;&#x201C; this might help her find her way around (11) DOWN 1 Withdraw record held

by Madrid club (6) 2 Chemist had some of Garboâ&#x20AC;&#x2122;s children (5) 3 Bone in neck ape broke (7) 5 Cellular features said to be more humorous (5) 6 Fowl took off, itâ&#x20AC;&#x2122;s reported, fleeing this? (4,3) 7 Lover or church? Astronauts feel it intensely (1-5) 8 Nuclear reactionâ&#x20AC;&#x2122;s ability to sustain itself, sceptics would have it? (11)

18 Complex pattern of French law on aluminium (7) 20 Implied sensitivity, myself included (5) 22 Climbing plants with drug moving back in tubes (5) 23 Silver and spirit found in Turingâ&#x20AC;&#x2122;s coat, adding information (7) 24 Look to pull queen backwards (6) 25 Northern Ireland and Gibraltar initially stay in the European Medicines Agency? Turingâ&#x20AC;&#x2122;s cracked it! (6)

14 â&#x20AC;&#x153;One is getting older,â&#x20AC;? as American writes: this could reveal the workings of her mind (7) 15 Recklessly augment harmful chemical (7) 16 Illness causing passion for waiting in line? (1,5) 17 Part of flower that is viewed negatively (6) 19 Heads of Turingâ&#x20AC;&#x2122;s agency sought every reason to develop shocking weapon (5) 21 Hold cold fish (5)

Answers and the next quick crossword next week.

52 | New Scientist | 21 September 2019

#22 The 9-minute egg I like my eggs to be boiled for exactly 9 minutes. The problem is that I have no way to measure time except for two egg timers that are able to measure precisely 4 and 7 minutes respectively.

There is more than one way to set up the timers to measure exactly 9 minutes, but I am keen to eat my egg as soon as possible. Can you help?

2 Pan troglodytes and Pan paniscus are the sole members of the Pan genus.

How are they better known?

1 In mathematics, the continuum hypothesis advanced by Georg Cantor in 1878 concerns the possible sizes of what quantity?

3 What is the main chemical component of standard glass?

4 John Bardeen, Walter Brattain and William Shockley shared the 1956 Nobel prize in physics for which discovery?

Answer next week

5 The hallux is the biggest of your whats?

#21 Six weeks of seconds Solution

Answers below

The number of seconds in six weeks and the product of all the whole numbers from 1 to 10 inclusively (10!) are the same: 3,628,800.

Here is how to show they are the same without a calculator:

Quick Crossword #40 Answers ACROSS 7 Brown rat, 9 Inlier, 10 Womb, 11 Complexity, 12 Taipei, 14 Apple DOS, 15 Expansion slot, 17 Cyclamen, 19 Arsine, 21 Rhinoceros, 22 Mole, 23 Aments, 24 Endogeny

The number of seconds in six weeks is 6 weeks x 7 days x 24 hours x 60 minutes x 60 seconds Now, rewrite these numbers as products of smaller numbers.

DOWN 1 Areola, 2 Swab, 3 Friction, 4 Dial-up, 5 Alex Bellos, 6 Beetroot, 8 Tympanic nerve, 13 Pipelining, 15 Erythema, 16 Nearside, 18 Mucosa, 20 Nylons, 22 Mega

For example: 24 = 3 Ă&#x2014; 8 60 = 5 Ă&#x2014; 4 Ă&#x2014; 3 which gives you: 6 x 7 x (3 x 8) x (5 x 4 x 3) x (5 x 2 x 3 x 2) which equals: 6Ă&#x2014;7Ă&#x2014;3Ă&#x2014;8Ă&#x2014;5Ă&#x2014;4Ă&#x2014;3Ă&#x2014;5Ă&#x2014;2Ă&#x2014;3Ă&#x2014;2

Quick quiz #21 Answers

GETTY IMAGES

1 Infinity. It states that while the infinity of real numbers (all numbers you can order along a line) is larger than the infinity of just the integer numbers, there is no level of infinity between the two 2 The chimpanzee and the bonobo 3 6LOLFRQ GLR[LGH 6L2Ä&#x2039; 4 The electronic transistor 5 Toes

Puzzle set by David Bedford

Reorder and adjust this sequence, noticing that 10 = 5 Ă&#x2014; 2, and 9 = 3 Ă&#x2014; 3 = (5Ă&#x2014;2) Ă&#x2014; (3Ă&#x2014;3) Ă&#x2014; 8 Ă&#x2014; 7 Ă&#x2014; 6 Ă&#x2014; 5 Ă&#x2014; 4 Ă&#x2014; 3 Ă&#x2014; 2 = 10 Ă&#x2014; 9 Ă&#x2014; 8 Ă&#x2014; 7 Ă&#x2014; 6 Ă&#x2014; 5 Ă&#x2014; 4 Ă&#x2014; 3 Ă&#x2014; 2 = 10!

Get in touch Email us at crossword@newscientist.com puzzles@newscientist.com

The back pages Feedback Elongated eels

Mind your mouths

A two-year forensic trawl of Loch Ness in Scotland has concluded that its most famous resident may be a large eel.

Researchers from New Zealand’s University of Otago sifted DNA samples from the loch to see what sorts of creatures were hiding in its depths. The analysis found nothing to suggest the presence of any of the usual Nessie suspects, which in recent years have included plesiosaurs, whales and even large fish such as sturgeon or catfish.

There was, however, plenty of eel DNA. “Our data doesn’t reveal their size,” said researcher Neil Gemmell, “but the sheer quantity of the material says that we can’t discount the possibility that there may be giant eels in Loch Ness.”

Alternatively, perhaps lots of regular-sized eels are slithering around in a giant eel costume, terrorising the occasional visitor and enchanting the local tourist board.

The sea monster head count is rising. Last month, conservationists working on Hilton Head Island in South Carolina reported the discovery of a two-headed loggerhead turtle hatchling.

Meanwhile, Fox News showed a picture of a two-mouthed fish reeled in by angler Debbie Geddes in upstate New York.

That’s not all: in New Jersey last month, a two-headed timber rattlesnake christened Double Dave was recovered by conservationists, while another two-headed serpent was spotted in Bali.

What’s going on? Hypotheses, speculation and glowing antinuclear screeds to the usual address please.

Lost at sea More submarine mysteries, this time in the Baltic Sea. Researchers from the GEOMAR Helmholtz Centre for Ocean Research in Kiel, Germany, are scratching their heads after their underwater monitoring station vanished overnight. The seabed observatory at Eckernförde Bay, in place since 2016, stopped transmitting data on 21 August. When divers arrived at the scene, they found nothing but a shredded cable that once fed power to the station.

The BBC reports that the area is off-limits to fishing boats.

Yet experts said the 770-kilogram observatory was too heavy to be moved by storms, tides or large animals (or, presumably, lots of little animals wearing a large animal costume). In a statement, GEOMAR researcher Hermann Bange asked beachcombers to report anything suspicious washing up on shore. Though with £270,000 of equipment at stake, Feedback thinks the local pawn shop might also be worth a visit.

Picture of the week The future

Bottle rockets All Jedi warriors are advised to put thermal detonators in their checked luggage before passing through airport security.

The US Transportation Security Administration (TSA) previously stated that the existing ban on “replica and inert explosives” included souvenir soda bottles from Disney’s Star Wars: Galaxy’s Edge theme parks, which are designed to resemble the fictional firecrackers.

But millions of voices cried out in protest, and feeling this great disturbance in the force, the TSA has taken the offending bottles off the no-fly list. The grenade-shaped plastic containers can even be taken in hand luggage – so long as the syrupy contents are emptied out first. Allowing liquids to be taken on flights? Now that really would be dangerous.

Jersey justice A Waitrose supermarket in St Helier, Jersey, has faced criticism for including a charity that raises money for alternative cancer treatments in a fundraising initiative.

Local shopper Anne F spied an in-store charity box raising money for “non-toxic cancer treatments as

ASIMO, the humanoid robot, sings and plays with a football four times a day at the Miraikan National Museum of Emerging Science and Innovation in Tokyo.

Courtesy of Penny Winters.

The next theme is nature’s patterns, to celebrate the change in seasons.

Email us your related photos to readerpics@newscientist.com by Tuesday 24 September.

Terms and conditions at newscientist.com/pictureoftheweek-terms an alternative to chemotherapy and radiotherapy”. This money would be used to create a repository of alternative cancer treatment books “that the Jersey Library don’t have at present and are not willing to stock”, as well as paying for patients’ treatments “not covered by their medical insurance”.

As the saying goes, if it looks like a quack and it quacks like a quack, then it’s probably a quack. After a Twitter outcry, Waitrose head office sprang into action, telling Anne the proposal was “done in error” and “we will not be supporting this charity”. It seems shoppers in Jersey will have to settle for scientifically verified treatments for now.

Naming names Feedback is relieved to find the spirit of nominative determinism is alive and well among the New Scientist readership. Still. John Hawkins writes that in our article on happiness “it is delightful to note that the author of a paper titled ‘Positive Psychology’ is Martin Seligman” (31 August, p 30).

The name means “Blessed Man” in German.

Meanwhile, Jack Haley notes that at the University of Florida Transportation Institute, a group examining the structural integrity of supra-aquatic transportation pathways is led by Jennifer Bridge.

Got a story for Feedback?

Send it to New Scientist, 25 Bedford Street, London WC2E 9ES or you can email us at feedback@newscientist.com 21 September 2019 | New Scientist | 53

The back pages Almost the last word Is sitting inherently bad for you or just time that could be better spent exercising?

Lightning bulb

Storm Dunlop East Wittering, West Sussex, UK The sizzling sound was almost certainly a corona discharge and is often heard before a nearby lightning flash. The discharge occurs when the electrical field between the cloud and the ground is strong enough to cause electrons to be emitted from the tips of any pointed objects – even, in some cases, from people’s hair.

As for why the light glowed, it depends on the type of lamp. If it is one that glows after being charged during the day, the flash may have provided sufficient charge for the light to come on. If it is activated by passive infrared (PIR) radiation, it is possible that the heat from the lightning was sufficient to activate the PIR sensor.

John Woodgate Rayleigh, Essex, UK Both effects are due to the electric field that is generated between the thundercloud and the ground.

The light is caused by a current that is induced in the wiring of the lamp by the varying electric field through its accompanying magnetic field. These fields persist for a while at a lower level than the very strong fields created just before and during a strike.

Anthony Richardson Ironbridge, Shropshire, UK It is unclear whether the bulb was powered by the intense light absorbed from the lightning by the solar panel or, in a less likely scenario, by charge absorbed from the air. The sizzling sound must be the sound of the air being explosively expanded in the lightning channel.

54 | New Scientist | 21 September 2019

GETTY IMAGES

A summer storm woke me around 2 am. I heard a sizzling sound before lightning struck about 100 metres away. Then I saw a 1.5-volt solarpowered outside light glowing like a 50-watt bulb. It faded after a few minutes. What caused the sizzling sound and made the light glow so brightly?

This week’s new questions Sitting pretty We are frequently told we need plenty of exercise and that sitting is bad for us. Is the problem with sitting merely that it stops you exercising, or is sitting bad in itself? John Gordon, Datchworth Green, Hertfordshire, UK Coil conversion If I compress a metal spring, tie it with an acid-proof binding then submerge it in acid and dissolve the spring, what happens to the energy that was used to compress it? I think the acid must warm up, but how is the stored energy converted to heat? Roger Key, Bedale, North Yorkshire, UK

Hard-baked Why do crisp ginger biscuits go soft if left exposed to the air for a couple of days when other baked products, such as cakes and bread, go hard?

Krista Nelson Rokeby, Tasmania, Australia The difference between a cake and a biscuit is similar to the difference between bread and toast. Bread starts out soft and moist but dries out over time and becomes an unpleasant mix of soft and dry. Toast is made by drying out bread to make it crisp.

As toast ages, it absorbs moisture, making it rubbery and unpleasant.

Biscuits are the toast of the cake world and were originally made by baking cakes twice to dry them out for storage. If you leave a cake and a biscuit in a standard kitchen, the moist cake will dry out and the dry biscuit will become soggy, both approaching the same state, just from different directions.

Claire Gregson Portadown, County Armagh, UK Biscuits are essentially dried cakes, so absorb ambient moisture. Cakes are much more moist, so evaporate water to the surrounding air. Just eat and enjoy.

David Jackson Liverpool, UK Biscuits start out with a very low moisture content of between 1 and 3 per cent, depending on the type, whereas this is around 15 to 30 per cent for cakes. In an atmosphere of moderate humidity, water will diffuse out of a cake and into a biscuit until equilibrium is reached, not only with the entrapped air, but also the starchy, sugary matrix of the product.

In the 1990s, biscuit and cake manufacturer McVitie’s fought a

UK tax claim on its Jaffa Cakes.

Chocolate-coated biscuits are subject to value-added tax (VAT) in the UK, whereas chocolatecoated cakes aren’t, so a huge amount of money was at stake.

McVitie’s (my employer at the time) won the case, partly because cakes, including Jaffa cakes, become dry when they go stale, whereas biscuits go soft.

Gerald Dorey Oxford, UK This question is an example of the profound cake-biscuit existential problem exemplified by the Jaffa Cake. This chocolatecoated confection has provoked much discussion: a BBC radio programme that discussed the subject even invoked Ludwig Wittgenstein’s ideas of the futility of “family resemblance” tests, whether a categorisation is merely a semantic reflex and whether a non-binary category might be applied.

Lawyers are more practically minded, and in 1991, a UK VAT tribunal decided that the critical factor was whether the item absorbs moisture over time and becomes softer, as with biscuits, or gives up moisture and hardens, as with cake. This confirmed that the Jaffa Cake is a cake, and is therefore liable for a lower rate of tax than it would have been if classified as a biscuit.

Clearly, the ambient humidity is critical. I would suggest that in countries with weather that is hot and humid enough to melt the chocolate on a Jaffa Cake, no cake would harden, nor would a biscuit stay hard for long. The reverse would be true in deserts.

In both areas, the cake-biscuit duality disappears. ❚

Want to send us a question or answer?

Email us at lastword@newscientist.com Questions should be about everyday science phenomena Full terms and conditions at newscientist.com/lw-terms

The back pages The Q&A

Cartoonist and former NASA roboticist Randall Munroe wanted to know how to land a space shuttle in a drainage ditch, and went to astronaut Chris Hadfield to find out As a child, what did you want to do when you grew up?

When I was very little, I had a book that showed some people building a house, so the first thing I can remember wanting to be is a housebuilder. A little later, I started reading comics, and I actually remember thinking that it would be really neat to be a cartoonist. But then I realised that I only knew how to draw stick figures, so I abandoned that idea – only to stumble on it by accident a decade or two later.

Explain what you do in one easy paragraph.

I draw comics and post them on the internet, where people look at them when they’re supposed to be working on something. I also write books about cool maths and science.

What do you love most about what you do?

I love learning about weird cool stuff and getting to tell people about it, but my very favourite thing is that I occasionally hear from people who got to know their future partner by sending my comics back and forth to each other.

How has your field of study changed in the time you have been working in it?

I was never a great student overall, and after a few years of feeling frustrated in science class, I remember thinking that I didn’t want to do science after all. But then I came across a physics textbook and realised that was the kind of science I was excited about.

If you could send a message back to yourself as a kid, what would you say?

I’d feel a lot of pressure to figure out the most important world event to warn people about. But I’d probably panic and just write: “Sorry about the paradox I’m creating right now :(”

What’s the best piece of advice anyone ever gave you?

My mom once told me she tries never to make fun of someone for admitting they don’t know something. I think that’s a really helpful lesson.

If you make fun of people for that, you’re just teaching them to avoid revealing to you when they’re learning something and you miss out on getting to show them cool stuff.

56 | New Scientist | 21 September 2019

What’s your favourite ‘How to’ from your latest book?

For the chapter “How to Make an Emergency Landing”, I interviewed Chris Hadfield, test pilot and commander of the International Space Station. My plan was to throw increasingly bizarre scenarios at him until he got annoyed, but to my surprise, he answered every question without hesitation. Even better, his answers were all delivered in a very businesslike astronaut voice. It was so much fun listening to him calmly describe how to crawl around on the outside of a plane or land a space shuttle in a drainage ditch as if he had done it a thousand times.

Do you have an unexpected hobby, and if so, please will you tell us about it?

Every fall, I spend a few days hiking up to mountain lookouts to help count migrating hawks. I was very into the Animorphs series of books as a kid. K. A. Applegate spent a lot of time describing hawks riding thermals.

It sounded so nice!

What’s the best thing you’ve read or seen in the past 12 months?

Gretchen McCulloch’s book on how the internet shapes language, Because Internet, sheds light on so many things that I’ve noticed but never really understood about how people use text to communicate.

How useful will your skills be after the apocalypse?

I guess it depends whether there are surviving people who have free time and want to hear cool facts about the apocalypse that just happened.

OK, one last thing: tell us something that will blow our minds…

The first nuclear weapon was created closer to the invention of barbed wire than to today. ❚

Randall Munroe is an engineer, author and creator of the web comic xkcd. His latest book, How to: Absurd scientific advice for common real-world problems, is out now TOP: RANDELL MUNROW; BOTTOM: PHOTO RESEARCHERS/FLPA

“My mom told me she tries never to make fun of people for not knowing something”

SOUVENIR ISSUE

MOON LANDING 5OTH ANNIVERSARY 1969-2O19

THE QUEST FOR SPACE

Donâ&#x20AC;&#x2122;t miss a special souvenir issue from New Scientist celebrating the 50th anniversary of the moon landings. Explore the past, present and future of space exploration with over 100 pages of in-depth articles on the wonders of the solar system, plus 20 pages of newly resurfaced historical content from New Scientistâ&#x20AC;&#x2122;s archive detailing the original space race as it happened

Available from all good magazine retailers, digitally in the New Scientist app or direct from

newscientist.com/thecollection