New scientist 13 8 2016

fungus, the bogeyman

The mushrooming threat of fungal diseases

victimless crime?

Sex robots that satisfy illegal desires

dressed for success

Our fashion choices left the Neanderthals behind

WEEKLY 13 August 2016

every last drop How to save our most precious resource

ocean worlds

The search for life in the solar system’s other seas

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Contents

Volume 231 No 3086

This issue online newscientist.com/issue/3086

Leaders

News

3

6

News

Down’s syndrome brain boost

4 UPFRONT

Glimpse of rare sand cat. Obamacare works.

England’s reforestation blip. No sign of sterile neutrinos 6 THIS WEEK Vanishing particle at LHC. Brain’s sewage system. China’s flood myth is true. Venus was habitable. Neanderthal fashion faux pas. Moderate exercisers have bigger hearts 13 IN BRIEF

Sunflower’s dance decoded. Bee colony forms a lung. Smiley baby monkeys. Cancer clock. Fat ages brains. Plastic data storage

plainpicture/Maskot

Drugs may help memory, but the benefits are unproven

time we became eco-warriors on water.

It’s Don’t rush to publish premature explanations

On the cover

29

34 Fungus, the bogeyman Mushrooming disease 20 Victimless crime?

Sex robots that satisfy illegal desires 10 Dressed for success Neanderthal fashion 16 Every last drop How to save our most precious resource 26 Good for nothing What makes us generous

Ocean worlds The search for life in the solar system’s other seas

Cover image Valerii Ilnitskii

Analysis 16 Rethinking water We must change how we use our most precious resource 18 comment

A creationist Ark is no place for a school trip.

Soft solutions needed for the hard problems 19 insight Why gene doping should be allowed in sport 44 BREXIT

Science gets stuck in a bad place

Technology 20 Curbing dark desires. Batteries smooth the way for solar. Algorithm spots sarcasm.

Brain-mimicking crystals sift big data

Features

34

Aperture

Fungus, the bogeyman

Features

24 China’s rainbow layer cake mountains

26 Good for nothing Why humans are so uniquely generous 29 Ocean worlds (see above left) 34 Fungus, the bogeyman (see left) 38 PEOPLE Emmanuel de Merode and Virunga’s gorillas

ron kurniawan

The mushrooming threat of fungal diseases

Culture

Coming next week…

Life’s many beginnings

Early Earth teemed with experiments in evolution

Poker lessons

42 World of connection Marconi was no Einstein, but his intuition brought us radio 43 Tudor time capsule Mary Rose, rebooted

Regulars 52 letters Hazards of sex and childbirth 56 Feedback Litter-picking CCTV cameras 57 The Last Word People-tasting

What Texas hold ‘em says about strategy and risk

13 August 2016 | NewScientist | 1

AF archive/Alamy

LEADERS

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by Williams Gibbons (Wolverhampton)

The stillsuit mentality It’s time we all became eco-warriors for water IN Frank Herbert’s science fiction classic, Dune, the inhabitants of the titular desert planet survive by wearing “stillsuits” that recycle every drop of water they excrete, coupling ecological temperament with martial discipline.

Water is vital to life as we know it. That’s why our search for aliens focuses on worlds that harbour it (see page 29), or once did (page 8), as does our search for worlds on which we might one day settle.

Hence the difficulty in finding economic models for responsible water use: how do you agree a fair price for such a vital commodity?

But we do need to act. Between rising population, megacities, pollution and climate change, the next few decades will see water

stresses on a vast scale. The grave difficulties already apparent in the western US and Australia will afflict many more areas of the world. Ethiopia is gripped by the worst drought in decades; with it comes the spectre of famine.

Water conservation poses technical challenges, too. For example, it’s difficult to clean up used water, so rather than reclaim useful substances – nitrates or phosphates, say – we throw them away. We may also assume, without particularly convincing evidence, that pollutants are diluted enough to pose no risk to human or environmental health.

But enough suspicion lingers that few people would call recycled water their drink of choice.

Too much, too soon TO MANGLE a metaphor, you shouldn’t count your needles until you’ve finished searching the haystack. A promising bump in measurements made at the LHC has vanished, and with it hopes of a new dawn for highenergy physics (see page 7).

Such false starts are to be expected, so physicists talk in statistical jargon about how likely anomalies are to be real. “Five

sigma”, meaning odds of one in 3.5 million that a result is down to random fluctuations, counts as a discovery like that of the Higgs boson. The latest bump, when announced last December, barely ranked two sigma: odds of one in 20 of being down to chance.

Normally, physicists wouldn’t even get out of bed for that. Yet theorists, starved of new physics, produced more than 500 papers

That’s changing. While we may not agree on a price for fresh water, we are starting to see the value of using both recycled water and impurities extracted from it in industry. That has provided incentives to reshape the entire system (see page 16).

We will still need to grapple with booming demand. That means doing a better job of public education about water use, and being tougher on rampant exploitation of scarce resources.

You might call it the stillsuit mentality: fierce, perhaps, but better an eco-warrior mindset now than water stress giving way to water wars in future. And better frugality today than life eked out on a parched planet tomorrow. n

claiming to explain the result.

Excitement accounts for some of this frenzy, but much was just hastily rehashed old theories being reapplied in the hope they might catch on this time.

Alas, with the bump gone, these papers are unlikely to trouble the Nobel committee any time soon.

Perhaps next time, theorists should heed experimentalists’ statistical warnings, and hold off until there is better data. Without it, they are really just writing fan fiction for the universe. n 13 August 2016 | NewScientist | 3

Joe Raedle/Getty

Upfront

US health gets better OBAMACARE’S check-up looks good.

expanded Medicaid to more people.

The Affordable Care Act – President Obama’s initiative for expanding healthcare for poorer people in the US – has already had positive impacts on the nation’s health.

The law, passed in 2010, expanded coverage under the government healthcare programme Medicaid to more adults on low incomes.

States were left to decide how to expand Medicaid. To compare different approaches, researchers asked thousands of adults on low

In both Arkansas and Kentucky, the team found that people were now more likely to have a personal physician, get a check-up, and receive regular care for chronic conditions.

They were less likely to skip taking drugs or visiting the emergency room due to costs. Fewer people reported trouble paying their medical bills (JAMA Internal Medicine, DOI: 10.1001/jamainternmed.2016.4419).

But similar improvements were not seen in Texas. This suggests that the

incomes across three states about their health, between 2013 and 2015.

Kentucky expanded Medicaid access outright, while Arkansas used federal funds to buy private insurance for poorer adults. Texas is among 19 states that have not yet

approach states take to expand Medicaid doesn’t matter too much as long as they go ahead and do it, says Benjamin Sommers at Harvard University, who led the study. “If you don’t expand, then people are not going to get these benefits,” he says.

Lake in hot water

colleagues used sediment cores from the East African lake to study proxies of temperature, algal production and abundance of fish fossils over the past 1500 years.

They found a correlation between warmer periods and fewer animals. This is because surface waters are fertilised by an upwelling of nutrient-rich water, which has been hampered by rising temperatures.

This reduces oxygenation in the lower water layers and has cut populations of the algae, molluscs and crustaceans that the fish eat (PNAS, doi.org/bnqk).

–Turns out they’re right–

No neutrinos

and theorists were convinced it existed.”

Theorists had hoped that sterile neutrinos could explain both dark matter – the mysterious particles thought to make up the bulk of our universe – and why the universe began with an imbalance of matter and antimatter that prevented the cosmos from annihilating itself from the start.

Sterile neutrinos would also extend the standard model of particle physics, hinting at a new direction for our understanding of particles and the forces that govern them.

A PARTICLE ghost has been laid to rest. Physicists have spent decades hunting for “sterile neutrinos”, a fourth flavour in addition to the three known neutrinos, of which trillions pass through your body

unnoticed every second. Now they’re pretty sure it doesn’t exist.

The IceCube Neutrino Observatory at the South Pole is the latest to join the hunt.

A new analysis of almost 100,000 neutrino events hitting its detectors, which are buried deep in the ice, has found no sign of the sterile version – concluding with 99 per cent certainty that it doesn’t exist (Physical Review Letters, doi.org/bnqh).

“Like Elvis, people see hints of the sterile neutrino everywhere,” says Francis Halzen at the University of Wisconsin-Madison, who heads the experiment.

“There was this collection of hints, 4 | NewScientist | 13 August 2016

mike lane / Alamy Stock Photo

“Like Elvis, people see hints of the sterile neutrino everywhere. Theorists were convinced it existed”

AFRICA’S oldest and deepest lake is getting ever warmer, a trend that is hitting biodiversity and will affect local fisheries.

Overfishing contributes to the loss of biodiversity in Lake Tanganyika, but a study of core sediments is now showing that 500 years of sustained climate warming has probably been a larger driver. This has led to a decline in fish abundance that predates commercial fisheries.

Andy Cohen at the University of Arizona in Tucson and his

Sand cat is back BLINK and you’ll miss it. The Arabian sand cat is a shy and secretive animal only seen in the desert at night. Now, after a 10-year absence, three have been glimpsed on camera in Abu Dhabi.

A team led by Shakeel Ahmed, an assistant scientist at The Environment Agency Abu Dhabi (EAD), captured 46 photos of the cats in Baynouna, a protected area. The sightings were usually –Purrrfectly adapted to desert life– made late on moonlit nights and

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

Chimera ban review

at cooler times, suggesting the cats prefer low temperatures for foraging (European Journal of Wildlife Research, doi.org/bnqj).

The sand cat is well adapted to its desert home. It doesn’t need to drink water as it can get all it needs from the small animals that are its prey. Special hairs in its ears and on its paws keep the sand out.

We know little about the cat’s biology, and populations may be declining. The team hopes its work will help inform conservation strategies. “Scientists need to be doing more research on how the sand cats live,” says John Newby at the Sahara Conservation Fund.

IT’S too promising to ignore. The US National Institutes of Health (NIH) is rethinking its stance on some research involving adding human cells to animal embryos.

Since 2009, the funding body has banned the creation of certain types of human-animal chimeras.

Such work may be useful for growing human organs for drug testing, transplants and research.

But it poses a number of ethical concerns, including fears that having human cells could make animals think more like us.

The 2009 moratorium banned

60 Seconds

human pluripotent stem cells from being added to early monkey embryos. Now, the NIH is considering allowing an expert committee to review certain types of proposed chimera work, on a case-by-case basis. It also plans to clarify some of the rules around early-embryo monkey chimeras.

“I’m confident these proposed changes will enable the NIH research community to move this promising area of science forward in a responsible manner,” said Carrie Wolinetz, the NIH’s associate director for science policy. The changes could mean the ban is lifted in early 2017.

Grand tree planting plan stalls

Zika in the US

The National Forest Company

TENS of thousands of people in THE ambitious plan to reforest a swathe of central England is slowing the US could already be infected down. The UK’s visionary National with the Zika virus, following Forest scheme aims to turn a third of travel abroad. a 500-square-kilometre area near This figure was extrapolated the city of Derby into forest. from the number of pregnant But the last few years have seen women confirmed to be carrying successive drops in the amount of the virus after visiting countries new planting and the goal may not be where Zika is established, such reached for another half a century. as Brazil.

The scheme celebrates its 25th With help of data on air travel anniversary this year and has and the spread of the virus, transformed abandoned industrial Alessandro Vespignani at landscapes such as opencast mines Northeastern University in and quarries into woodland. Some Boston, Massachusetts, and his 8.5 million trees have been planted, team calculated that the number boosting forest cover to 20 per cent. of infected returnees to the US so But the rate of planting has far could be as high as 43,300 dropped from over 500 hectares a (bioRxiv, doi.org/bnqg). year at its peak in the early 2000s to Oliver Brady at the London School of Hygiene and Tropical Medicine says multiple data sources support Vespignani’s predictions, but they may be an overestimate. For example, many travellers from the US can afford to stay in air-conditioned hotels and use insect repellents, and these factors reduce the risk of infection.

Nevertheless, based on Vespignani’s estimate, it seems likely that many people are already carrying the virus in the areas of the US inhabited by the Aedes mosquito, which is capable –Cash-strapped– of spreading it.

a new low of 110 hectares in the year 2015-2016. “We’re down to 100 hectares a year at a push,” says John Everitt, chief executive of the National Forest Company.

The causes are partly economic.

Land prices are rising and the landowners who form the backbone of the voluntary scheme have more options for their land, including tourism spin-offs from the forest.

What’s more, much of the easily converted land has already been planted and resources are now being diverted to managing the forest.

But Everitt says the target has not changed. “We still want to be ambitious,” he says. “Even if it takes decades, that’s fine because forests are a long-term venture.”

Reef grief in Maldives Corals in the Maldives face whiteout this year – 60 per cent are bleached because of global warming and exceptionally high sea temperatures triggered by the El Niño weather cycle. In some areas, up to 90 per cent of corals are affected, a new survey has found.

Baffling star The mystery deepens. A star called KIC 8462852 flickers so erratically that some speculate that only an “alien megastructure” can explain its behaviour. A further look showed it has been fading for a century.

But fresh analysis suggests the star has also dimmed more rapidly over the past four years – adding to the enigma.

Medals over morals Russia has been banned from competing in next month’s Paralympics after evidence of a state-sponsored doping programme.

“The anti-doping system in Russia is broken, corrupted and entirely compromised,” said Philip Craven, president of the International Paralympic Committee. Russia is to appeal the decision.

Not Yutu!

The moon just got a little more lonely. Last week China announced that its lunar rover Yutu, or Jade Rabbit, has finally stopped operating after 31 months on the surface.

Over 100 scientific papers have been published using data from the rover, including the discovery of a layer of lava flows no one had spotted before.

Earth overshoot day We’ve already eaten up our annual supply of Earth’s renewable resources, according to the Global Footprint Network. The date by which we “overshoot” by consuming more than the planet can produce in a year keeps getting earlier. Carbon emissions are the fastest growing contributor to ecological overshoot.

13 August 2016 | NewScientist | 5

plainpicture/Maskot

This week so some parents have decided to give it to their child on the basis of this early evidence. Women are also choosing to take it while pregnant with a baby that has Down’s syndrome, says Carol Tamminga at the University of Texas Southwestern Medical Center in Dallas.

Tamminga has now begun a small placebo-controlled trial of Prozac in pregnant women.

However, she has found that many families would rather try Prozac themselves than risk being allocated to the trial’s placebo group. “Those who are potentially interested in doing this are doing it anyway,” she says.

A different compound has produced small positive benefits when tested in people. EGCG, an extract from green tea, reduces the activity of an enzyme that is –Prozac memory boost?– overproduced in the brains of people with Down’s syndrome.

In July, a placebo-controlled trial in 84 adults reported small improvements in some tests involving memory, reasoning and mental focus. Although changes were modest, over a lifetime they could lead to improved abilities, Families are using drugs that haven’t been fully tested, finds Clare Wilson says André Strydom at University College London.

DRUGS that change the chemistry fertilised egg ends up with an “There’s a lot of hype. We have Neuroscience Societies and structure of the brain could extra chromosome. This affects seen with autism that parents conference in Copenhagen, boost the intelligence of people every cell in the baby’s body and will do anything to enhance the Denmark, last month. with Down’s syndrome. can lead to problems such as heart cognitive ability of their child,” In 2015, her team found that Several compounds have disease and an early susceptibility using a drug called bumetanide to says Tom Shakespeare, a disabled improved memory and learning in to dementia. block this molecule made Down’s activist and researcher at the a mouse version of the condition, The IQ of people with the syndrome mice perform as well as University of East Anglia in suggesting that its cognitive effects condition also tends to be about Norwich, UK. We need more other mice in memory tests. The can be changed. Until recently, 50 points lower than the general drug is already used to treat heart evidence about the safety and this idea was unthinkable, average, although there is wide effectiveness of potential Down’s “ We have seen with autism says Mara Dierssen at the Centre variability. People with Down’s syndrome medication, he says. that parents will do for Genomic Regulation in syndrome seem to have fewer Rather than trying to develop Barcelona, Spain. neurons in some brain areas, fewer anything to enhance their drugs, it would be better to change child’s cognitive ability” Such efforts to improve brain connections between neurons, our education and work systems function are controversial, with and altered neuron behaviour. to enable people with Down’s some activists saying people In both mice and people, a syndrome to live fuller lives, says disease, and trials in adults with should be valued as they are. But molecule called NKCC1 seems to be Down’s syndrome are set to start Simone Aspis at the UK campaign some families have decided to give involved. Reducing levels of this group Changing Perspectives. towards the end of this year, their children drugs like Prozac compound in neurons taken from says Cancedda.

But Shakespeare says that if that have not yet been thoroughly Down’s syndrome mice makes such drugs prove to be safe and Prozac has also been found to tested for Down’s syndrome. them sprout more connections, effective, they could help give boost memory in Down’s “Many more studies have to be Laura Cancedda of the Italian people with Down’s syndrome syndrome mice – perhaps by done first,” says Dierssen.

Institute of Technology in Genoa more independence: “I’ve no making extra neurons grow. The Down’s syndrome arises when a told the Federation of European drug is a common antidepressant, objections to this in principle.” n

Drugs may lift IQ in people with Down’s syndrome

6 | NewScientist | 13 August 2016

In this section n Neanderthal fashion faux pas, page 10 n We must change how we use our water, page 16 n Curbing dark desires, page 20

THIS is how you clear your mind.

Researchers have had the best look yet at microscopic vessels that take waste away from nerve cells in the brain.

The first clear picture of this network, called the glymphatic system, came in 2012 from experiments in mice. The network seems to ramp up when we sleep, removing unwanted metabolic by-products and waste proteins like beta-amyloid, but many details, including the exit route this waste takes, are still unclear.

To examine the system in people, Vesa Kiviniemi of the University of Oulu in Finland and his colleagues have developed a souped-up form of MRI scanning that takes 20 times as many photos per second. With this high resolution they followed the biological trash as it was flushed through the network.

It was thought that the pulsing of blood through the brain’s arteries provided all the force necessary for pushing waste through the glymphatic system, but the scans have revealed that other forces are involved. Muscle cells around blood vessel walls seem to give an extra squeeze, and our lungs may be involved too. When we breathe in, pressure changes in our chest seem to help draw the waste fluid down the pipes. “It’s kind-of sucking the glymph out of the brain,” says Kiviniemi.

“This is a very big deal,” says Joel Ramirez of Sunnybrook Health Sciences Centre in Toronto, Canada.

In an experiment yet to be published, Kiviniemi and his team have found that the pulsing of waste fluid in two people with Alzheimer’s disease appears to be subtly different from that seen in people without the condition.

Problems with the glymphatic system may contribute to Alzheimer’s by letting beta-amyloid, which is implicated in the disease, accumulate in the brain. Clare Wilson n

Alastair Philip Wiper/Corbis/Getty

How waste pulses through your brain

corner.” This time, that didn’t check out.

CMS spokesperson Tiziano Camporesi remains confident. “I have no doubt that the accelerator is going to deliver, and it’s up to the experiments now to take the challenge,” he says. There’s certainly plenty to look for. Gaps in the standard model leave much potential for the existence of new physics: it fails to account for the mass of neutrinos, the behaviour of gravity or the existence of dark matter and dark energy.

“Nature is screaming at us from the sky that there is dark matter, lots of it, there is dark energy,” says Gibson. “We would sure like to have some hints of that in our colliders.”

–Some particles are easy to spot– There is an air of inevitability about the search, even as this particular blip fades into memory.

“Our job is to kill the standard model: it’s what we do,” says Blekman. “There are many ways to do that, and we are still LAST week, physicists from CERN All is not lost for those theories, discovering more and more announced disappointing news: though, says CMS researcher ways, but it might take 20 years.” a potential new particle, set to Freya Blekman at the Free Experimenters will continue shake up modern physics, doesn’t University of Brussels, Belgium. to pick at the edges of the exist. So what will they do now?

“These fluctuations really drive standard model, scrutinising the The dream had lasted almost the creativity in the theoretical behaviour of the heaviest and eight months, since the ATLAS section of our field,” she says, lightest particles. They will keep and CMS collaborations found an and a breakthrough may change looking for new particles that unexpected bump in their data everything. “It could still be that one could point to exotic physics like last year. The detectors at the of those 500 papers is totally true.” supersymmetry, in which every Large Hadron Collider (LHC) particle in the universe has a near“Our job is to kill the had measured more proton identical partner particle. standard model, it’s pairs with a shared energy of Bumps like the one at 750 GeV what we do. But it might 750 gigaelectronvolts (GeV), crop up all the time; mostly they take 20 years” than is predicted by the standard fade away with more data, but model of particle physics. once in a while, as with the Higgs If the detection had turned out But proving that will take a boson in 2012, they stick around to be genuine, this could have while. The LHC is now functioning to provide enormous insights into pointed to a new particle. close to its highest possible the deeper workings of nature.

Theorists produced more than energy levels, meaning there More results from the LHC’s 500 papers on how such a find aren’t likely to be any more most recent run will be released would affect our understanding sudden surprises. “There are a in coming months, but the most of particles and forces. But data few chances in the life of a collider complicated analyses of data gathered this year and presented where it feels like there is a big could take years. On top of that, at the International Conference opportunity, where you take a it will be decades before the on High Energy Physics in Chicago big step in energy,” says former next generation of planned on 5 August confirmed that the ATLAS researcher Adam Gibson, particle accelerators comes excess was a statistical fluke, the now at Valparaiso University, online to continue the search for equivalent of getting a surprise Indiana. “All of a sudden there’s exotic physics. It looks as if the run of heads when flipping an the chance that there was universe is going to make us wait.

Leah Crane n ultimately fair coin. something just around the

What next after mooted new particle vanishes?

13 August 2016 | NewScientist | 7

This week

Was Venus once a sweet spot for life? unusually high ratio of deuterium to hydrogen atoms, a sign that it once had water delivered to the surface by comets, as we think happened on Earth.

The team applied an Earth climate model to four versions of the primeval Venus, each varying slightly in details such as the

IT’S everything our planet is not: scorching hot, dried out and covered in toxic clouds. No wonder Venus is sometimes dubbed Earth’s evil twin.

But a mere one or two billion years ago, these two siblings might have had more in common.

New simulations back the idea that the early Venus could have looked a lot like Earth – and been habitable.

“It’s one of the big mysteries about Venus. How did it get so different from Earth when it seems likely to have started so similarly?” says David Grinspoon at the Planetary Science Institute in Tucson, Arizona. “The question becomes richer when you consider astrobiology: the possibility that Venus and Earth were very similar during the time of the origin of life on Earth.”

Grinspoon and his colleagues aren’t the first to imagine Venus as a hospitable world. It’s similar to Earth in size and density, and the fact that the two planets formed close together suggests that their compositions are similar, too. Venus also has an

Rocks bear out story of China’s ancient flood LEGEND has it that a great flood engulfed China 4000 years ago.

Lasting more than 20 years, the deluge was finally tamed by the heroic efforts of Emperor Yu, whose Xia dynasty marked the birth of Chinese civilisation.

Some had dismissed the story as a myth, but we now have compelling evidence that the flood did happen at 8 | NewScientist | 13 August 2016

BABAK TAFRESHI/National Geographic Creative

Aviva Rutkin

the time and place chronicled in the legend – about 1920 BC. “This was the first stage in the founding of Chinese civilisation,” says Qinglong Wu, now at Nanjing Normal University in China, who led the study.

His team discovered ancient rocks and sedimentary formations in the Jishi Gorge, in the upper reaches of the Yellow river, that could only have existed as a result of a cataclysmic flood. They also found evidence of an earthquake and analysed the skeletons of three children killed by it.

Together these helped the team

amount of energy the planet receives from the sun, or the length of its day. They also added a shallow ocean one-tenth the volume of Earth’s oceans.

The models show that Venus might once have looked much like an early Earth and remained habitable for a much of its existence to date. The most promising of the four Venuses enjoyed moderate temperatures, thick cloud cover and even the occasional light snowfall (arxiv. org/abs/1608.00706).

Could life have emerged on this

early Venus? The team isn’t ruling it out. But if it did, it is certainly no more, thanks to the oceans boiling away and volcanoes reshaping the landscape around 715 million years ago.

“There are great uncertainties in understanding Earth, not only its climate history but the history of how life began,” says Michael Way at the NASA Goddard Institute for Space Studies in New York City. If the theory that it began in oceans on Earth is right, it may also have got started on a soggy Venus.

“Both planets probably enjoyed warm liquid water oceans in contact with rock and with organic molecules undergoing chemical evolution,” says Grinspoon. “As far as we understand at present, those are the requirements for the origin of life.”

A future Venus mission should look out for signs of water-related erosion, the team suggest, to uncover evidence of past oceans.

NASA is weighing up two Venus projects, one to drop a probe through the clouds down to the surface, the other to orbit the planet and image its surface.

The study could also aid astronomers in their search for exoplanets, says James Kasting at Pennsylvania State University.

If Venus might have once been habitable, then it suggests that other planets close to their stars –Next door’s not so hospitable now– might be, too. n

establish a timeline of events.

(Science, doi.org/bnh9).

“The first thing was the earthquake, and this triggered a huge landslide that blocked the river,” says Darryl Granger of Purdue University in West Lafayette, Indiana. The dammed water formed a lake 200 metres deep, before breaching months later.

Rocks and debris deposited by the floodwaters around the children’s

“ The hero Yu was able to control the flood, bringing order from chaos and founding the first dynasty”

home show the earthquake and flood must have happened within a year of each other. When the lake burst, it released a huge volume of water – between 12 and 17 cubic kilometres.

According to historical accounts, it took Yu 22 years to bring the floodwaters under control through massive dredging operations. He then founded China’s first dynasty, marking the transition to modernisation.

“In the accounts, the hero Yu was able to control the flood through dredging, bringing order from chaos,” says David Cohen at National Taiwan University in Taipei. Andy Coghlan n

C9 Moonphase

Jochen Tack/imageBROKER/ageFotostock

This week 24,000-year-old carved figurines from Siberia suggest hoodies were in vogue.

Also, weasel, wolverine and dog remains are found at sites occupied by humans – but not at Neanderthal sites. The fur of these animals is a mix of long and short hairs, making it ideal as a trim added to sleeves or hoods. Collard thinks ice age humans could have used fur trims for added insulation, but not Neanderthals.

Fur was used for its function, rather than fashion, says Collard.

“However, there is reason to suspect that early modern human clothing had a stylistic dimension,” he says. “They produced beads and there appear to be multiple –Stylish Neanderthals wore capes– clear regional or stylistic groups.”

Ian Gilligan, formerly at the Australian National University in Canberra, thinks Neanderthals lived fashion-free lives. “I suspect it is only with fitted garments – what I call complex clothes – that symbolic and fashion elements become important.” more common at human sites.

But Neanderthals might not Humans may have created have been completely clueless complex garments, each stitched when it came to personal together from several animal appearance (see “Neanderthal skins, and so caught more chic”, below). animals. Neanderthals might John Stewart at the University have caught fewer because they of Bournemouth, UK, isn’t wore much simpler clothes. convinced. He says bones at an The idea is that Neanderthals archaeological site might be made capes of fur, or even simply indicative of animals hunted for wore the skin of a large animal food instead of fur. “You need to around their shoulders. Modern look at the bones of the animals humans, meanwhile, might have and find evidence that they were opted for a more practical look; skinned – and you can’t do that by what Collard calls “close-fitting studying a database,” he says. n sewn garments”. A collection of

Hoodies were in vogue in ice age Colin Barras

EARLY modern humans dressed for ice age success – Neanderthals, not so much. An analysis of animal remains at prehistoric hominin sites across Europe suggests modern humans clad themselves in snug, fur-trimmed clothing, while Neanderthals probably opted for simple capes.

Some researchers argue that Neanderthals didn’t bother with clothes at all, others that they dressed like our ancestors did.

Mark Collard at Simon Fraser University in Burnaby, Canada, and his colleagues think the truth lies somewhere in between.

They checked a database of mammals that lived from 60,000 to 24,000 years ago in ice age Europe. Next, they used a database of world cultures to identify mammals traditional peoples now exploit for their clothing. When they compared the animals’ abundance at Neanderthal and early human archaeological sites, mammals such as deer, bison and bear were 10 | NewScientist | 13 August 2016

NEANDERTHAL CHIC Ice age Neanderthals living in Europe might have opted for simple clothes (see main story), but they did accessorise.

Around 130,000 years ago, Neanderthals living in a cave in what is now Croatia might have strung eagle talons together into necklaces – no mean feat given how hard it would be to get the talons.

Perforated seashells found in

50,000-year-old deposits in a Spanish cave contain the remnants of pigments, so some researchers think they might have been pendants.

And a collection of 44,000-yearold bird bones found at an Italian cave look as if they’ve been scraped with stone tools where the feathers were once attached. Perhaps Neanderthals removed the feathers to use as ornaments.

Heart may swell suspiciously with exercise YOU don’t have to be an Olympian to have a big heart. People who exercise for only 3 hours a week can have an enlarged heart too, and may be wrongly diagnosed as having a heart condition as a result.

Elite athletes are well known to have enlarged hearts, but no one had realised a similar phenomenon can occur in people who do a moderate amount of exercise. Declan O’Regan at Imperial College London and his team discovered this by scanning 1096 people with healthy hearts.

“Once exercise exceeded 3 hours, we saw a large impact,” says O’Regan.

“Almost half our subjects who exercised for five hours a week or more had enlarged hearts.”

The left ventricle, which pumps oxygenated blood to the body, was 2.4 times as likely to be larger in those who exercised for between 3 and 5 hours a week than in sedentary people, and 4.4 times as likely in those who exercised for even longer.

The right ventricle, which pumps deoxygenated blood to the lungs, was 9.1 times as likely to be enlarged in those doing 5 or more hours of weekly exercise (Circulation: Cardiovascular Imaging, doi.org/bnqf).

O’Regan is concerned about the risk of misdiagnosis based on these changes. Of those people that did 5 hours’ or more exercise, 42 per cent had right ventricles that would prompt a diagnosis of dilated cardiomyopathy, a progressive heart condition.

“We’re talking about completely healthy hearts, but the risk is that they get misdiagnosed as diseased,” says O’Regan. This can have a major psychological impact on affected individuals.

O’Regan wants physicians to check how much their patients exercise before making any diagnosis. “It shines light on the need for doctors to use a whole range of tests to diagnose cardiomyopathies,” says Joel Rose at the charity Cardiomyopathy UK. Andy Coghlan n

The life and work of Alan Turing

Alan Turing is arguably one of the greatest scientists of the modern age. Join us as we explore his life, work and greatest achievements and learn more about this fascinating figure in 20th century science

4 – 8 NOVEMBER 2016

�

STUDENT DAYS Cambridge

�

DAVIDE CIOFFI/ FINE ART IMAGES /GETTY IMAGES

Visit King’s College where Turing studied mathematics and went on to lay the theoretical foundations for modern computers. Marvel at the chapel’s famous Gothic architecture and medieval stained glass. Our guided tour of the city includes the American Cambridge cemetery and the Eagle pub, where Francis Crick first announced that he and James Watson had discovered DNA. After dinner, enjoy a talk by intelligence expert Mark Baldwin and a demonstration of a rare fourwheel Enigma machine.

(other

dates available)

CODE BREAKERS Bletchley Park

Soak up the atmosphere of the huts where Enigma messages sent by the Germany military were decrypted. Visit Turing’s office to see how it would have looked during the second world war.

Discover the ingenious mathematical techniques and devices that Turing and his colleagues designed to crack the Enigma code. At the nearby National Museum of Computing, see a rebuild of Colossus the world’s first electronic computer. Reminisce over the museum’s collection of home computers from the 1970s and 1980s.

�

TORTURED GENIUS Manchester

After the war, Turing became deputy director of the computing laboratory at the University of Manchester. Here he worked on software for one of the earliest computers, the Manchester Ferranti Mark 1 and conducted pioneering work into artificial intelligence. He also turned his attention to pattern formation in biology, though his life was cut short in 1954. Our guided tour of Manchester takes in key locations associated with Turing, from the university and Museum of Science and Industry to the old cinema where a liaison led to tragic consequences.

WHAT’S INCLUDED � Four nights’ bed and breakfast � Welcome reception, dinner and lecture � Second night dinner with wine and talk � Private coach � Local expert guides � All talks, admissions and guided tours

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in Brief

plainpicture

Plastic chains could be super data store

Why some sunflowers track the sun and others don’t HERE comes the sun. The dance of the sunflower reveals a sophisticated ability to exploit its environment.

morning, away from the sunrise. They found that leaves of both groups of sunflowers were about 10 per cent smaller than leaves from plants that were allowed to follow the sun. “They’re less efficient if they can’t track,” says Harmer.

To understand why sunflowers in bloom stop moving

The heads of young sunflower plants follow the sun during the day, then reverse course at night so they’re ready to face the dawn. But no one knew how much of an advantage the plants gain from their daily routine, or why they cease to track the sun once they have bloomed.

To find out, Stacey Harmer at the University of California, Davis, and her colleagues tethered some

and face the rising sun,the researchers rotated some sunflowers so they were facing west, then recorded how many bees and other insects visited the plants.

The east-facing flowers received about five times as many pollinators as the west-facing ones, probably because they were warmer, which attracts pollinators (Science, doi.org/bngk). “You can see the bees going

young plants so they couldn’t move, and rotated the pots of others so they were facing the wrong way in the

crazy over the east-facing flowers and mostly ignoring the west-facing flowers,” says Harmer.

Mutations add up to bring cancer closer HOW old will you be when cancer strikes? Your genetic mutations can add up to make it sooner.

We already know that mutations in some genes strongly increase cancer risk. But now David Thomas at the Garvan Institute of Medical Research in Sydney and his team have shown that mutations in genes linked with a low cancer risk can little by little add up to a deadlier effect.

They analysed 72 genes in thousands of healthy individuals and in 1162 people with sarcomas – cancers that develop in bones and soft tissue, often in young people.

Some of the genes they examined are strongly linked to sarcoma, like TP53, while others are only weakly linked.

As expected, a TP53 mutation increased a person’s risk of getting sarcoma – half of them developed

cancer by the age of 32. But people with mutations in two genes each only weakly associated with sarcoma developed tumours at a younger age – half had cancer by the age of 25 (Lancet Oncology, doi.org/bnjd).

Thomas is now offering MRI body scans to people with mutations like these in their DNA. “We’re picking up cancers that are asymptomatic, and because they’re in the early stages, we can actually cure them,” he says.

ONE day your hard drive could just be a pile of plastic. Researchers have coded a word into plastic molecules, which could be used as a space-saving way to store data.

Jean-François Lutz and his colleagues at the Institut Charles Sadron in Strasbourg, France, have been experimenting with chains of plastic molecules that can encode information.

These chains are made up of two kinds of molecules that stand for the 1s and 0s in digital code.

They wrote the acronym CNRS, the abbreviation for the French National Center for Scientific Research, across six polymers – a 32-bit message when encoded using standard ASCII characters.

To read the message, the chains were sorted from shortest to longest using a mass spectrometer and sequenced by breaking them apart molecule by molecule.

(Angewandte Chemie International Edition, doi.org/f3qs9r).

Baby monkeys smile while asleep SWEET dreams? Baby Japanese macaques smile more while sleeping than human or chimp infants – the only other species known to smile in their sleep.

Fumito Kawakami at Kyoto University in Japan and his team filmed seven snoozing infant macaques and found that they smiled 41 times an hour during rapid eye movement (REM) sleep, which is associated with dreams (Primates, doi.org/bngs).

“We are not sure what is triggering this smiling in their brains,” says Kawakami. Such spontaneous smiles probably help develop facial muscles for social smiling later on. Another possibility is that the infants grin in response to their dreams, but this is difficult to test, he says.

13 August 2016 | NewScientist | 13

in Brief

SHOOTING sponges could refine the way police solve crimes.

Forensic investigators have long studied blood spatter stains to work out details of a crime. The size of the droplets reveals the speed of the impact, and thus if a wound was made by bullets or blunt weapons.

But existing methods for analysing blood spatter patterns are incomplete, says Alexander Yarin at the University of Illinois at Chicago. “None of these approaches even ask the question, what is the origin of droplets?” he says. “What is the physical mechanism of formation of drops, and their initial sizes and velocity?”

Yarin and his colleagues modelled the pattern made as blood from a gunshot wound hits a surface.

The model incorporates physical features of both the bullet and blood. The interplay between air and a denser fluid like blood is what determines initial drop size and velocity, Yarin says.

To test the model, the team fired bullets at sponges soaked in

Marcus Lindstrom/getty

pig’s blood. The resulting spatter patterns showed mixed results: the droplets were generally close to the model’s predictions, but varied considerably between trials. The team is planning to run more trials with different bullets to refine the model further (Physical Review Fluids, doi.org/bngh).

14 | NewScientist | 13 August 2016

Quantum computing rivals go head to head IN THE race to build larger quantum computers, two contrasting strategies have drawn neck and neck. Both sides can now create simple devices that run multiple types of quantum software.

In May, IBM made a quantum computer available for anyone to use over the internet. It uses five quantum bits, or qubits, so can only handle relatively small problems – but it’s programmable just like a PC. IBM uses superconducting qubits built using techniques

from the conventional computer chip industry.

Now, a team at the University of Maryland in College Park has made a programmable five-qubit computer using a different approach (Nature, doi.org/bngr).

These qubits are made from ytterbium ions held in place by magnetic fields and lasers.

“Ions are nature’s quantum units,” says team member Shantanu Debnath. “If you have a bunch of them in a processor, all of them are identical, and that is a significant advantage.”

Trapped-ion qubits have another edge over the superconducting variety in being able to communicate with each other at a distance, thanks to the weird property of quantum entanglement. This lets them process data more easily.

In contrast, superconducting qubits can swap data only with their nearest neighbour, meaning two distant qubits have to slog through all those in between to communicate. “That is something they are going to pay for in the long term,” says Debnath.

Dong Lei/NaturePL

Sponges to help crack gun crime

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Too much fat may age your brain MIDDLE-AGED spread may affect the brain, too, making it look a decade older .

A study of 473 adults found a link between being overweight and having less white matter, which connects different brain areas and enables signalling between them. The volume of white matter in the brains of overweight people aged 50 was similar to that seen in the brains of lean people at 60 (Neurobiology of Aging, doi.org/bngp).

“As our brains age, they naturally shrink in size, but it isn’t clear why people who are overweight have a greater reduction in the amount of white matter,” says team member Lisa Ronan at the University of Cambridge.

The effect was only seen from middle age onwards, perhaps because we are particularly vulnerable in some way at this time of life, says Paul Fletcher, another team member at the University of Cambridge. “It will be important to find out whether these changes could be reversible with weight loss,” he says.

However, overweight people did not show impaired performance in cognitive tests.

Giant honeybees act as collective lung HONEYBEE push-ups might cool the hive. When it’s hot, Asian giant honeybees may chill their colonies through synchronised movements

within a few minutes, and were more numerous during the hottest part of the day (PLoS One, doi.org/bngm).

The spots may be areas where

that suck cool air into the nest, then push warm air out.

To protect their open-air comb, layers of bees form a living insulating cloak called the “bee curtain”. Gerald Kastberger of the University of Graz, Austria, and his colleagues filmed nine colonies near Chitwan National Park in Nepal with infrared video cameras. The footage revealed small cool spots on the surface of the bee curtain that appeared and faded

cooler air from outside the nest is being drawn into the overheated interior, as bees in the innermost layer push their legs against the comb to create a cavity between the curtain and the comb. “The cooler nest spots are analogous to our nostrils,” Kastberger says. When the bees relax, the curtain would hug the comb again, forcing hot air out.

Push up, breathe in. Relax, breathe out. At least, that’s the theory.

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Live Smarter

analysis rethinking water

Not a drop to drink Staving off a global water crisis requires a formidable rethink about how to value it, says Sally Adee

without it, which is why the UN in 2010 declared access to clean water a universal human right.

That limits the price you can put on municipal water. Then there’s the issue of what happens when people can’t pay.

Damon Winter/NYT/Redux/eyevine

Wealth from waste

–Parts of California’s are sinking

ZIKA isn’t the only thing hanging over the Rio Olympics.

The city’s water problems are so intractable that swimmers have been told to keep their mouths closed so that they don’t ingest sewage. The situation is an important consequence of the shoddy way we all treat our water.

Beyond Rio, evidence of our disregard for the wet stuff is all around, and it is starting to bite.

Beijing has sucked so much water out of the ground that the city is sinking by 11 centimetres a year.

That’s positively glacial compared with parts of California’s Central Valley, which are dropping by 5 centimetres per month.

In Connecticut, nuclear power plants have shut down for lack of 16 | NewScientist | 13 August 2016

water to cool the furious reactions head of environment at the World inside, and coal power stations in Economic Forum.

India have shut due to droughts.

At its heart, the issue can be Concerns have been raised that traced back to a simple but California may run out of water perplexing question: how do you to fight its wildfires. And in give water a value? One way is to February, protesters sabotaged assign a price that reflects its a canal supplying Delhi’s water – importance or scarcity. In other two were killed by armed forces words, treat water as a commodity sent to secure the canal. like oil. This was a fashionable In the not-too-distant future, we refrain in the water world for could see entire cities abandoned – much of the last decade. ghost town casualties of drought But the biggest problem with and water mismanagement. It is setting a price is that the value of not overly dramatic to say that the water is incalculable. All humans world’s “use once and throw are reliably dead after a week away” attitude has enabled a slowmotion water apocalypse. “We’re “ Rather than treating water like oil, we should going to have to do something or think of it the way we we’re all going to be juddering to think of renewables” a halt,” says Dominic Waughray,

Perhaps rather than commoditising water like oil, we should be thinking of water the same way we think of renewables.

This isn’t about building hydropower dams on every river, but considering whether it is possible to contain an area’s water inside a reusable, closed loop system that reduces waste while making money from the stuff the water carries.

At the moment, it’s common to take water from a source like an aquifer or a river, use it once for drinking, agriculture or industry, and then flush the result into a central municipal treatment plant. This is referred to as the linear model of water use.

This processing requires huge amounts of energy and leaves behind a foul sludge that is costly to dispose of.

Several things have happened in the past few years that could provide alternative ways of doing things, with the advantage of extracting value in the process.

First, water purification techniques have advanced.

“You can take the worst industrial waste and turn it into incredibly high quality drinking water,” says Peter Gleick of global water think tank the Pacific Institute. “It’s just a matter of economics.” The process is expensive, but now there are several designs for microbial fuel cells that generate electricity from sewage and industrial waste, mitigating the expense. It has also become cheaper to recover useful substances from water. For example, we can now extract agricultural fertilisers like ammonia, phosphorus and nitrates from sewage.

For daily news stories, visit newscientist.com/news

As a result, people everywhere, from the European Commission to the corporate advisers who inform policy makers in places like water-stressed South Africa, are talking about replacing the linear model with a circular approach (see “Closing the loop”, right).

The most radical vision is a city based on a perfectly closed loop, with water flowing from one application to the next on the basis of the purity required for each. For example, your drinking water could become household sewage that irrigates agricultural fields, whose run-off then goes to industrial use or to enable fracking. After its final use, the water returns to a treatment plant. “Then you treat it all again, and return it to drinking water, and the whole thing starts again,” says Waughray. “But now the plants can get energy and fertiliser out of the water and monetise treatment.”

This may sound far-fetched, but various components of this model have been around for a long time. The technology is now at a point where it’s possible to envisage the separate parts being stitched together.

Singapore is the most advanced in treating sewage – its NEWater is so pure it is used in hypersensitive microchip fabrication plants, and supplies 30 per cent of the population’s water needs. Other places around the world, including Texas and Orange County, California, are beginning to accept the idea of toilet to tap recycling.

Switching to renewable water is a formidable task. To pull all these aspects together into a waterefficient city will require a huge infrastructure overhaul.

However, many cities are already starting to look at distributing water treatment instead of centralising it, which would make it possible to harvest its valuable contents at different points along the cycle – and reduce the formidable cost of pumping it around a city. “It takes a lot of energy to move water

Closing the loop A closed loop water system avoids costly centralised treatment – it can even extract value and generate energy while processing waste Source (e.g aquifer)

Drinking water

Treatment works

Heavy industry

betting on the pop-up towns and cities that are attracting millions of people from rural areas in places like China. These places are being constructed from scratch so can be built around the guiding principle of clean water.

All the unknowns

Even if the logistics pan out before these water-centric cities can be built, some big questions need to be answered about how to make Black sure what re-enters the loop as water drinking water is safe.

Methane: Energy Fuel The biggest concern for Ernest Polymers Biodegradeable Blatchley, at Purdue University plastics in Indiana, is the chlorine that is Treatment Fertiliser Treatment still used in places like London to works works kill any biological pathogens – not the chemical itself, but its disinfection by-products.

“We have identified more than Agriculture Treatment Light works industry 700 chlorination by-products,” he says. Whether these are present in In the case of energy, every around,” says Gleick. One of the concentrations that elicit adverse method of generation requires goals in Sydney’s 2030 vision human health effects is not fully massive amounts of water. statement is to have distributed known, but there’s definitely treatment points around the city. According to the US Geological potential for them to negatively Survey, cooling the turbines of the affect human health, he says.

More worryingly, many country’s coal fired power plants countries don’t prioritise water The good news is that many requires up to 320 trillion litres of utilities are moving away from at the most basic administrative water per year – that’s the amount chlorine and toward UV for level. In the US, for example, of water that runs off Niagara Falls disinfection, says Fred Royan, “there’s no department of in five months. “Get the energy water,” Waughray says. an analyst at global business companies on side,” Waughray While it’s tempting to think research firm Frost & Sullivan. says, “and all of a sudden you of that as a bug in the system, One of the world’s biggest have some really powerful people UV-treatment plants has just Waughray thinks it can become a feature, because sectors that need pulling strings to make it happen.” opened in Washington DC. So where will the first true water should be motivated to No one is saying it will be closed loops be? Waughray is invest in ways to improve access. easy, but we need to solve the problem sooner rather than later, says Gleick. If we continue Whose wee is it anyway? business as usual, it is estimated If you live in London, the joke is that make more sense when cities use that by 2030 global demand for your tap water has already been a closed water cycle. By 2060, water will exceed viable resources through seven people. Like all good Singapore will get 55 per cent of its by 40 per cent. jokes, there’s some truth in it, but water directly from sewage.

And if the worst case realistically none of us uses new The joke reflects our discomfort scenario happens – we ruin water. “All the water in the world with water that has been “prethe planet so the whole things has been here since the dinosaurs,” owned”, something that’s likely to be looks like Rio’s oceans of sewage – says Ernest Blatchley at Purdue worse in a smaller hydrological cycle. we’ll have an even more pressing University in Indiana. “In fact, the But anything undesirable in the small case for perfecting this circular water you’re drinking has probably system also exists in the bigger water economy. “Anyone who been through a dinosaur.” one – just dispersed more widely. wants to get off the planet has to Figuring out how many humans “We all live downstream,” says bring all their water with them,” your water has been through will Blatchley. “It’s just a matter of scale.”

Blatchley says. “And that’s all they’ll have.” n

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13 August 2016 | NewScientist | 17

comment

That sinking feeling A Noah’s Ark “theme park” stuffed full of creationist pseudoscience is no place for educational visits of any sort, says Josh Rosenau IN A quiet corner of Kentucky, what claims to be the world’s largest timber-frame structure is hard to miss – a “life-size Noah’s Ark” that cost $100 million.

Called Ark Encounter, this “theme park” features stuffed creatures and a petting zoo. It opened last month, billing itself as a family-oriented educational treat. That makes it sound like a good place for school visits.

Not so fast. Promotional material also describes the park as “a Christian evangelistic outreach intended to bring the Ark of Noah’s day to life”, which “equips visitors to understand the reality of the events that are recorded in the book of Genesis”. It is a hardcore creationist extravaganza replete with pseudoscience – no place for field trips.

But that hasn’t stopped founder Ken Ham from urging publicly funded schools to come.

Throughout the Ark, signs, animatronic mannequins and videos insist it is no Sunday school tale, but a “historically authentic” boat that existed just as Ham and others on the young-Earth creationist fringe imagine it.

It is now offering reduced rates to tempt schoolchildren – $1 a student, and teachers go free.

Educators and parents should know that a trip wouldn’t educate or entertain, it would misinform and browbeat.

In any event, the Constitution of the US prohibits government bodies, including schools, from endorsing one particular religious belief over others.

Ark Encounter is all about endorsing Ham’s reading of Genesis as the literal truth.

What’s more, everything in the park is designed to promote scientifically impossible ideas.

From astrophysics to zookeeping,

Prevention is better…

Medical science alone can’t get us out of an epidemic of lifestyle diseases, says Luke Allen THE march of obesity, diabetes, cancer and heart disease seems to be unstoppable. Such noncommunicable diseases or NCDs cause 70 per cent of deaths worldwide and threaten to bankrupt health systems.

Appropriately alarmed, the World Health Organization has invested heavily in prevention 18 | NewScientist | 13 August 2016

social, political and economic environments are much stronger drivers of disease than genetics, biology and individual choice.

Where we are born, live, work and age are vital factors for health and many people have little control over these things. Only by influencing them can we turn the tide. But first we need to properly understand those factors.

Much has been written on the biology of atherosclerosis, and we have a good knowledge of stroke

and control. Its work has usually focused on bioscience, pharmaceutical treatment and public health messages.

But let’s be clear – such efforts have not dented the worrying rise “ We are still struggling to in these conditions. That’s why fathom how the outsized the WHO is shifting its focus. health impact of inequality The global health community can be reduced” has long acknowledged that

and diabetes on a similar level.

By contrast we are still struggling to fathom how to reduce the outsized health impact of inequality. Even less space has been given to understanding the many forces that influence what we eat, the health impact of trade agreements, and the regulation of tobacco, alcohol and junk foods.

Progress requires researchers versed in law, economics, sociology and political science.

That’s what the WHO’s Global Coordination Mechanism for NCDs is all about. It was set up late in 2014 for precisely this task – to coordinate attempts to combat the major causes of chronic

For more opinion articles, visit newscientist.com/opinion

Josh Rosenau is programs and policy director of the National Center for Science Education in Oakland, California

diseases, rather than looking for new ways of treating symptoms.

That’s not to say that the WHO has ditched drugs. DirectorGeneral Margaret Chan has described the hard balancing act of treating those who are ill while trying to prioritise prevention.

Economic and nutritional transitions to Western-style diets are occurring worldwide, exacerbating the rising tide of NCDs, and demanding political, economic and societal solutions.

Encouraging more research into these will be vital. n Luke Allen is a UK doctor and a former global health consultant at the WHO

INSIGHT Next generation doping

mike kemp images/getty

the visitor is deluged with misinformation. It may be impossible to find a single sign in the park free of scientific errors.

For example, Ark Encounter is founded on the notion that all the walking and flying animals alive today descend from specimens caged on a boat so unwieldy that it surely would have twisted apart in the roiling waters of a biblical flood. It is a notion that founders on the rocks of biogeography, genetics and marine engineering.

Just as pernicious as religious proselytising and scientific errors is a subtler form of indoctrination.

The relentless message is that our world is as fallen and wicked as Noah’s, and that the destruction of the flood – including the obliteration of all humans other than a virtuous few – was not just acceptable but praiseworthy.

Under the pretence of illustrating a beloved tale shared

by Jews, Christians, Muslims and others, Ark Encounter presents a message as socially divisive as it is scientifically inaccurate, instilling fear, hatred and hopelessness.

Those are lessons no school or parent should want their students or children to take on board. n

–Is fairness an illusion?–

Gene doping is coming, so let’s embrace it ELIZABETH PARRISH of anti-ageing could boost performance, and if they company BioViva claims to have given are added directly to muscle they may herself two kinds of gene therapy, not be detectable in blood. Worse still, one of which causes muscles to stay with gene editing technique CRISPR, it will be possible to make more subtle strong even if you don’t exercise – and grow faster if you do. changes to our genetic makeup that It’s not clear whether Parrish really could be impossible to detect. has done this - or if it works. But you There is only one sensible option: can be certain that BioViva is already accept that we can’t stop gene doping, hearing from sportspeople desperate and reverse the ban on it before to try it themselves. Gene therapists dangerous forms become common. say they often get such calls.

The most persuasive argument There have yet to be any against this is that it would force clean confirmed cases of athletes athletes to dope. As well as being genetically enhancing their bodies. morally objectionable, you would be But this could be because no one forcing them to accept the health risks has ever been tested. That’s about to “ Accept we can’t stop gene change. Last week the International doping and reverse the ban Olympic Committee said that athletes on it before dangerous in Rio will be tested for gene doping.

Conventional gene therapy involves forms become common” adding extra genes, whose sequence differs from a person’s own version of that doping carries. But many sports these genes. Blood samples from Rio are risky. American football can cause will be tested for added copies of a brain damage: should we ban that too? gene for a hormone called EPO, which An anonymous survey in 2011 stimulates the production of red blood suggests that more than a third of cells, giving athletes a big advantage. athletes engage in doping. Seemingly, Will this make the Olympics a fair many athletes already think they must competition? Far from it. There are dope in order to have any chance of several other genes besides EPO that winning. Allowing certain forms of

gene doping under medical supervision could reduce the risks they face, not increase them.

In fact, some gene doping could make athletes healthier. Lee Sweeney of the University of Florida, who is developing gene therapies for muscles, said it would be wrong to stop them having such treatments.

“I think it’s unethical to withhold from someone something that would actually allow their muscles to be much healthier now and in the future,” he told the BBC in 2014.

Then there’s the argument that people will lose interest in athletics if doping is allowed. Nonsense. Athletes already use one effective performance enhancer. It’s called caffeine.

Finally, fairness. Doping gives some competitors an unfair advantage. But sport is already unfair. Some teams have more resources than others, while some people have natural genetic advantages. We recognise the unfairness of one genetic difference: people with a Y chromosome mostly compete separately from those who don’t. Some sports also divide into weight divisions. Of course, some forms of gene doping could give athletes superhuman abilities, but such enhancements will be obvious.

The answer here is a separate category rather than an outright ban.

Like it or not, gene doping is coming.

Sporting authorities can’t stop them.

It will be far better if we embrace them instead. Michael Le Page n 13 August 2016 | NewScientist | 19

Artur Debat/Getty

Technology realistically to VR stimuli.

Renaud’s lab currently focuses on using VR for assessment, but he also plans to explore synthetic pornography for treatment.

There’s plenty of precedent: VR is increasingly used to treat phobias, post-traumatic stress disorder and schizophrenia.

For paedophilia, there are few other options. “It’s very difficult to treat,” he says. “You cannot change this sexual preference in itself as you can change a bad habit like smoking.” But perhaps VR – coupled for example, with cognitive behavioural therapy – could help people learn to cope with and understand their desires. In a controlled lab setting, a sex robot might make the –Is VR helpful or harmful?– simulations even more realistic.

Some scientists are cautiously optimistic about the idea. “It is possible that virtual pornography or robots might be a safer outlet for at least some individuals,” says Michael C. Seto, at Canada’s Royal Ottawa Health Care Group.

Paedophilia is difficult to diagnose and treat. Aviva Rutkin examines But Renaud cautions that it may bold claims that technology could help also have the opposite effect: a bot could normalise the behaviour LAST month, at the Forbidden past offenders reintegrate and must assess whether they and promote “the need to go Research event at Massachusetts harmlessly into society as well as pose a danger to others. To do so, further and to cross the line with Institute of Technology, a panel of helping prevent those who have he attaches subjects to a suite of real victims”. roboticists posed an inflammatory never offended from doing so. physical measurement devices, “We just don’t know,” says question. Should paedophiles be At the moment, there is a then exposes them to sexual Darling. “We have no idea what handed prescriptions for sex hidden population who have stimuli. In the case of direction this goes in and we can’t robots built to resemble children? urges but are desperate not to act paedophiles, the stimuli used to research it.” Funding is scarce, This isn’t as hypothetical as you on them. These people are at best be actual photographs of children and it isn’t easy to find a group of might think. Japanese company ignored by legal and medical obtained during police raids. That paedophiles willing to participate Trottla already ships child-sized systems that could help them. At practice was banned in Canada, in research. Any study would also sex dolls globally. Earlier this year, worst, mandated reporting laws so Renaud’s lab turned to audio be likely to provoke objections a Canadian man faced trial after mean that admitting those urges – from many corners – such as the “ Technology might help he was arrested for ordering such even when seeking help from a Campaign Against Sex Robots, to redirect dark desires a doll, which is considered child mental health professional – can which argued in a paper last year toward machines and pornography under Canadian law. trigger an official report and that technological sexual He could go to jail for seven years. social and legal consequences. It’s away from real children” substitutes haven’t been shown to But what if dolls like these could down to policies like these that we reduce demand for prostitutes. help rather than hurt? Ron Arkin, don’t know for sure how prevalent recordings describing sexual It’s only a matter of time a robotics engineer at the Georgia paedophilia is. Our best estimates scenarios. However, Renaud says before dolls like the ones sold Institute of Technology, and Kate suggest that it occurs in 0.5 to these aren’t sufficiently realistic.

by Trottla come with artificial Darling, who studies human1 per cent of the population.

So he began to wonder if VR intelligence. Will more realistic robot interaction at MIT argue VR is being mooted as a way pornography could do better, and technologies help reduce the that virtual reality and sex robots towards more accurate diagnosis. avoid the moral concerns posed problem, or make it worse? might function as an outlet to Patrice Renaud, a psychologist at by real pictures. In a series of We need to start figuring out what redirect dark desires towards the University of Montreal, experiments, he and his team the impact will be. As Arkin said at machines and away from real Canada, sees individuals referred showed that non-deviant men and the event, “The cost if we don’t children. If it works, it could help by the court or specialised clinics, sexual offenders both responded explore it is intolerably high.” n

Curbing dark desires

20 | NewScientist | 13 August 2016

ONE PER CENT

For more technology stories, visit newscientist.com/technology

THE dream of a solar-powered society has tantalised us for decades. But the costs involved in piping the sun’s energy into the electricity grid remain prohibitively high. Now, solar power could get the efficiency boost it needs – thanks to a corporate takeover.

Last week, Tesla, which makes batteries big enough to power your home – and also happens to make the biggest-selling electric car –

into huge vats of salt, which is good at absorbing heat. When the energy is required, piping water through the salt causes it to boil and produce steam that drives a turbine. In Texas, a giant array of batteries backs up the Notrees wind farm, keeping energy flowing when the wind dies.

Both projects turn unreliable renewable resources into dependable power plants – but at a cost. “While

announced that it is buying SolarCity, one of the leading installers of solar panels in the US. Backed by Tesla CEO Elon Musk, who co-founded both companies, the combined expertise could provide the breakthrough the fledgling solar industry needs.

The price of solar panels has fallen significantly in the last decade, but providing stable power from solar is

deployment of storage is increasing,

into data on electricity demand, weather forecasts and electricity prices, as well as data from the solar panels and storage system itself. The software uses all this information to make better decisions about when to charge and discharge batteries, increasing their lifespan. It can also help energy providers balance supply and demand, ironing out peaks.

Tesla and SolarCity could do the same. With batteries in cars and homes that can store solar power for when it’s needed, Tesla can smooth the supply of solar power to the grid.

A similar approach is already being tested in pilot schemes around the US.

it is not widespread,” says Matt Kromer, who leads the SunDial project at the Fraunhofer Center for

Arizona Public Service – the utility that serves the Phoenix area and plugs into the Solana plant – is in the midst of deploying solar panels and batteries to 1500 households.

Even though the panels and storage are spread across many rooftops, they are effectively roped together into a single 10-megawatt power plant that APS can control. The

more complex than just plugging in more panels. Grid operators need a way to store the sun’s energy to smooth out the supply during the night and when it’s cloudy.

Several experimental sites are

Sustainable Energy Systems in Boston.

Simply plugging solar panels into a battery isn’t enough, says Aminul Huque at the Electric Power Research Institute in Palo Alto, California.

Batteries get stressed every charging

SunDial project is planning a pilot in Massachusetts in which 2 megawatts of solar power and storage are controlled by the local utility company.

This kind of integration is exactly what the tie-up between Tesla and

exploring how best to do this for renewables like solar and wind. The Solana solar power plant in Gila Bend, Arizona, pumps excess heat energy

cycle and die quickly if they aren’t carefully managed.

To get round this, firms are turning to software. Kromer says SunDial taps

SolarCity promises – but on a much grander scale. There might soon be a power plant on every roof.

Hal Hodson n

Appen, a voice recognition firm working for Google, has put out a call on website Reddit for people with Scottish accents to submit recordings of themselves reading certain phrases to help train its software. Users with certain accents – particularly Scottish – have complained that voice recognition systems such as those used in Google Now and Apple’s Siri struggle to understand them.

119,756 The number of bitcoins stolen from Hong Kong exchange Bitfinex last J. EMILIO FLORES/The New York Ti/eyevine

“ Batteries that can store solar power until it’s needed will smooth the supply to the grid”

Nae bother

week. The theft of the bitcoins, worth around £55 million at the time, caused the cryptocurrency’s value to plummet 20 per cent.

One for the road It’s never a good idea to get a tattoo when you’ve been drinking – but putting one on before you start could save your life. A team at the University of California, San Diego, has designed a smart tattoo that detects alcohol levels in your sweat and sends a reading to your phone. The team hopes to cut down on drink-driving and says the patch’s sensor could also be linked to a car’s ignition system.

–Bring me sunshine– 13 August 2016 | NewScientist | 21

Reuters

How Tesla could change the solar power game

Halden Krog/The Times/Gallo Images/Getty Images Picture Credit

Technology AI learns to spot sarcasm in your tweets PICKING up on sarcasm online can be hard even for humans. For computers, it’s often a major headache. But now a machine learning system has learned to spot when you’re being sarcastic just by reading your past tweets.

Mining comments on social media is big business. Advertisers track our attitudes and moods, companies and governments follow public opinion.

But people being sarcastic and saying the opposite of what they mean makes this tricky.

So Silvio Amir at the University of Lisbon, Portugal, and his colleagues turned to machine learning. They trained the system to spot sarcasm on Twitter simply by looking at a user’s tweets. The software builds up a rich enough picture of a person that it can deduce when they’re being sarcastic,

jens karlsson/moment/getty

correctly interpreting tweets such as “ok thanks for being a great caring person! “ and “@BernieSanders and obama doing a great job.”

“It intuitively makes sense,” says Amir. “Tell me what you talk about and

–Data generators don’t come bigger–

Crystal chips mimic brain to sift giant piles of data

THERE’S nothing quite like the glass-like amorphous state. human brain. Last week, IBM When this phase change reaches a I can tell you who you are.” The team unveiled its latest attempt to certain stage, the crystal “fires” – will present their findings this week emulate it: an artificial neuron emitting an electrical signal much at CoNLL, a conference on language that switches between crystal like a neuron. A final energy pulse processing in Berlin. and glass-like states. then resets the crystal.

Dealing with sarcasm would be a The chip is designed for systems Conventional computer chips great help for marketers and customer that have to cope with huge operate as on-off switches, service teams, says Mark Carman at volumes of data – like those flipping in response to a voltage Monash University in Melbourne – not processing data from the Square change. By instead firing only to mention virtual assistants like Kilometre Array in South Africa Apple’s Siri. Edd Gent n and Australia (pictured) or those “ A brain-inspired chip could help filter out the garbage monitoring the stock exchange – from what’s interesting at a fraction of the energy cost of conventional chips. “Such a device to astronomers” could help filter out the garbage from what’s interesting to once a certain input threshold is astronomers,” says Chris Sciacca reached, the crystal chips should at IBM. be better at making sense of The artificial neuron is just a large amounts of chaotic data – micrometre across, and is made especially when working as a pack. from a chalcogenide-based crystal Imagine you wanted to monitor sandwiched between electrodes. thousands of Twitter accounts for Information arrives as pulses tweets that mentioned a specific of energy, which alter the phrase, says Tomas Tuma at IBM temperature of the crystal.

Research-Zurich in Switzerland.

As it heats up, it changes from an You could have a system that –I’m not a big drinker, me– ordered crystalline structure to a notified you of every single 22 | NewScientist | 13 August 2016

mention. But by having the chips fire only once the number of mentions passes a threshold, you’re more likely to pick up on something meaningful, he says.

To test the set-up, the team fired a broadband signal at packs of around 500 crystals. Each spiked at a slightly different time, but collectively they produced a discernible pattern that represented the incoming signal – a feat that resembles how groups of neurons work together in the brain (Nature Nanotechnology, DOI: 10.1038/nnano.2016.70).

Gert Cauwenberghs at the University of California, San Diego, is impressed. It’s the first demonstration of a phase-change device of this kind emulating the spiking of a biological neuron, he says.

The idea is not to replace existing processors, says Tuma.

Rather the chip could work alongside them. Yet Cauwenberghs thinks all computers might use chips of this kind one day, especially if advantages in energy efficiency hold up. “It remains to be seen if such technology can prove its chops to the computer industry.” Aviva Rutkin n

NS 16

Aperture

24 | NewScientist | 13 00 August Month 2016 2016

Rainbow cake mountain YES, this is a real place. Yes, it’s on this planet.

The vibrant colours of the mountains dotting China’s Zhangye Danxia Landform Geological Park in Gansu Province lend the peaks their nickname: the rainbow mountains. The strata were originally laid down horizontally, one on top of another, like the layers of a cake.

The mountains’ startling hues came from water and oxygen interacting with iron and other elements in the sediment, along with tiny amounts of other minerals left behind by groundwater creeping through the deposits.

Over millions of years, the layers were buried and solidified into rock. Their distinctive slant was caused by the same tectonic forces responsible for the formation of the Himalayas: as the Indian plate crashed into the Eurasian plate, beginning about 40 or 50 million years ago, the overlying land tilted and crumpled into mountains.

After the layers were elevated, erosive forces such as water and wind carved the craggy contours we see today. Emily Benson

Photograph Imaginechina/REX/Shutterstock

13 00August Month 2016 | NewScientist | 25

Generous by nature An ancient form of giving holds clues on how to promote human kindness, finds Bob Holmes

L

IFE isn’t easy as a Maasai herder on the Serengeti plain in eastern Africa. At any moment, disease could sweep through your livestock, the source of almost all your wealth. Drought could parch your pastures, or bandits could steal the herd. No matter how careful you are, or how hard you work, fate could leave you destitute. What’s a herder to do?

The answer is simple: ask for help. Thanks to a Maasai tradition known as osotua – literally, umbilical cord – anyone in need can request aid from their network of friends. Anyone who’s asked is obliged to help, often by giving livestock, as long as it doesn’t jeopardise their own survival. No one expects a recipient to repay the gift, and no one keeps track of how often a person asks or gives.

Osotua runs counter to the way we usually view cooperation, which is all about reciprocity – you scratch my back, I’ll scratch yours. Yet similar forms of generosity turn out to be common in cultures around the world.

Some anthropologists think it could represent

one of the earliest forms of generosity in human society.

That’s not the only curiosity about generosity. In biological and evolutionary terms, it makes no sense to give and get nothing in return. Altruism is rare in other animals, yet humans can be inexplicably kind.

Are we generous by nature? How did we get to be this way? What role does culture play in kindness? These are the big questions now being addressed by researchers in the Human Generosity Project, who are using fieldwork, experiments and modelling to explore osotua and other examples of human cooperation.

Their aim: to find how best to make the milk of human kindness flow.

A friend in need Osotua isn’t a responsibility the Maasai take lightly. “It is the connecting fibre in society,” says anthropologist Dennis ole Sonkoi at Rutgers University in New Jersey, who is

Arterra/UIG via Getty Images

Maasai (left) and Mongolian herders (above right) can expect help from their neighbours

26 | NewScientist | 13 August 2016

Maasai. Each individual maintains their own network of osotua partners. Once formed, the relationships can last for generations, with parents passing osotua partners on to their children. And it’s not just the Maasai. “In every society we’re studying, we have found needbased transfers,” says Human Generosity Project co-director Athena Aktipis at Arizona State University in Tempe. Fijians, Tanzanian slum dwellers and American cattle ranchers all pitch in to help neighbours in need, with no expectation of being paid back. Even the Ik of Uganda, whom one anthropologist once vilified as the least generous people in the world, do it.

But the giving is often one-sided. “Since I was a kid, there were families that I knew to have a lot of cows. Those families would be the ones that are always approached,” says Sonkoi. On the face of it, they seem to lose much and gain little by participating. Why do they continue to be generous, against their apparent best interests?

A clue lies in the trigger for such generosity: an unpredictable crisis. This suggests that these practices persist because they help manage risk, which pays off for everyone in the long run. Even the best-prepared family can fall prey to catastrophe, such as a sudden illness.

These types of risk cannot be prevented, so need-based giving may have emerged as a proto-insurance policy. Prosperous members of many societies share so that this social insurance will be available if they need it – just as wealthy homeowners insure their belongings against fire. “You’re exchanging the possibility of a catastrophic loss for the certainty of a small, controllable loss,” says Lee Cronk at Rutgers University, who heads up the Human Generosity Project with Aktipis.

Thinking of osotua-style generosity as insurance could explain why participants

Taylor Weidman/LightRocket via Getty Images

don’t keep a tally of who owes whom. “If you don’t help partners they may not survive, and then they may not be around to help you,” says Aktipis.

To investigate this idea, Aktipis and her colleagues made a computer simulation of a Maasai herding society. Each virtual household had a herd of cattle, which would grow through reproduction but occasionally be hit by a disaster. If numbers fell below 64 cattle – about what it takes to support a Maasai family – the household would die.

Aktipis’s team ran the simulation under three scenarios: one with no giving, one in which potential donors would only give if the asker had paid back previous gifts, and one

resembling osotua. Their newly published results show that households survived much longer, on average, with osotua-style giving, supporting the idea that even habitual donors benefit in the long run from keeping their neighbours going.

However, need-based giving works best when risks are “asynchronous” – when hardship is likely to strike one family and spare their neighbours. Herding tribes in northern Mongolia, for example, use such

“ Why do people continue to be generous, against their apparent best interests?”

generosity to help families crippled by illness.

However, the system breaks down when they face their biggest threat, a zud – a winter storm that prevents livestock from feeding. With everyone affected, helping one’s neighbours isn’t really an option.

This may also explain how the Ik got their reputation for selfishness, says Cronk. When anthropologist Colin Turnbull visited in the 1960s, he described them as “unfriendly, uncharitable, inhospitable and generally mean as any people can be”. But they had been pushed out of their traditional territory and were struggling with famine and war. Under such circumstances, they may have had little ability to help one another. > 13 August 2016 | NewScientist | 27

Mohamed Azakir/Reuters

LUIS MARDEN/National Geographic Creative

Westerners are quick to help in an international emergency, while Fijian generosity is closer to home

However, the ability to help isn’t enough in itself. To benefit from osotua-style generosity, you need to prevent cheating, for example asking when not truly in need. In some societies the solution is easy. “In the context of the Maasai, the things they’re most concerned with are livestock,” says Cronk. “It’s hard to hide them, so you can’t cheat.” In addition, osotua requests tend to be made in public, so everyone knows who has asked and given – or refused to give – says Sonkoi.

Where wealth is easier to hide, reputation is the key. In Fiji, for example, there is an osotualike practice called kerekere. “People can get reputations for being habitual kerekere-ers, implying they’re lazy,” says Matthew Gervais at Rutgers University. That makes them think carefully before making kerekere requests, which bring a slight taint of shame.

In fact, reputation doesn’t just inhibit cheating in kerekere: it appears to be the rock upon which generosity is built. Gervais gave 51 Fijian men a sum of money roughly equal to a day’s wages, and the choice of sharing their windfall with any of the other 50 men, all of whom they knew. Despite being told their decision would remain undisclosed, they proved surprisingly generous. On average, they kept just 12 per cent of the money for themselves, and 22 men kept nothing. When Gervais asked them how they chose who to share their money with, almost all said they gave to people who needed it. However, closer statistical analysis showed reputation was almost as important as need. Men with a reputation for giving tended to be the ones who received more.

Cronk believes that in day-to-day life, norms of generosity, love and respect drive decisions about sharing more than cold cost-benefit 28 | NewScientist | 13 August 2016

calculations do. This reinforces the idea that generosity is good. But the Human Generosity Project focuses on close-knit societies. Do humans become less generous when they live in more complex societies?

Of course, there is still need-based giving.

“When natural disasters occur, people donate,” says Aktipis. “And they donate because they know there is need, not because they expect they’re going to get good dividends on their donation to the Red Cross.” On the other hand, people in Western countries often walk past

encouraging generosity Research suggests ways to persuade people to give more generously to charity

1. Let givers build their prestige through donating.

“That’s what Bill Gates is trying to do when he gets billionaires to give away half their wealth,” says Joseph Henrich at Harvard University. This works for ordinary people, too, says behavioural scientist David Rand at Yale University.

2. Appeal in person, preferably to acquaintances.

Wesley Allen-Arave at the University of New Mexico surveyed the charitable giving of 515 New Mexican households and found that they were most likely to agree to a request from someone they knew – that criterion being more important than severity of need, says Allen-Arave.

3. Build empathy for the needy. That’s why so many charitable appeals feature photos of sad-looking children. Reading fiction featuring an unfortunate protagonist could make people more empathetic, and thus more willing to help someone in need an idea that Henrich hopes to test.

beggars on the street. But that could be because social institutions exist that they expect to step in and help. In fact, Westerners often give generously to strangers, whereas people living in smaller-scale societies tend to direct their generosity towards people they know. Fijians, for example, are very generous within their village. “But when we’ve had Fijians do games that involve giving to distant poor people, they seem almost baffled as to why anyone would send money to someone they don’t know far away,” says Joseph Henrich at Harvard University.

Nevertheless, osotua-style generosity offers some ideas about how to encourage charitable giving worldwide (see “Encouraging generosity”, left). And insights from the Human Generosity Project could help with some seemingly intractable problems.

For example, Aktipis is working with the authorities that manage southern Arizona’s scarce supply of water. The city of Phoenix has dozens of independent water providers that draw from a range of wells and other sources.

These vary seasonally and with the weather, so water availability can be unpredictable, leaving individual managers unable to meet demand. Aktipis hopes that by borrowing knowledge from need-based sharing, they will learn to cooperate more effectively.

In the future, this form of generosity could have a far more widespread and important part to play. It is possible that the social upheavals that accompany climate change and sea-level rise could overwhelm conventional insurance and social-assistance programmes. If that happens, it would be comforting to know that we can count on our neighbours for help. n Bob Holmes is a consultant for New Scientist

Hidden

depths

Oceans inside distant icy moons are the best prospects for finding life beyond Earth, says Joshua Sokol

S

UDDENLY, out of darkness, a ghostly city of gnarled white towers looms over the submersible. As the sub approaches to scrape a sample from them, crew-member Kevin Hand spots something otherworldly: a translucent, spaceship-like creature, its iridescent cilia pulsing gently as it passes through the rover’s headlights.

This is not a dispatch from an alien world, but it could be. Hand is a planetary scientist at NASA’s Jet Propulsion Lab in Pasadena, California, and one of a select few to have visited the carbonate chimneys of the Lost City at the bottom of the Atlantic Ocean.

It is the site of an extraordinary ecosystem – one > 13 August 2016 | NewScientist | 29

bottom left: NASA/JPL/SSI/Universities Space Research Association/Lunar & Planetary Institute bottom right: NASA/JPL-Caltech/University of Arizona/University of Idaho

30 | NewScientist | 13 August 2016

can interact with it. That turned out to be an astrobiologist’s fantasy: a plume of ice particles and water vapour shooting into space through cracks near Enceladus’s south pole.

Cassini has since flown through these plumes several times. First its instruments revealed the presence of organic compounds.

They seemed to be coming from a liquid reservoir – and the particles collected from lowest part of the plumes were rich in salt, indicative of an ocean beneath. Cassini detected ammonia, too, which acts as an antifreeze to keep water flowing even at low temperatures. All the signs suggested this was a sea of liquid water, stocked with at least some of the building blocks of life.

Treasure plumes “After decades of scratching around Mars to find any organics at all, this was an embarrassment of riches,” says Chris McKay, an astrobiologist at NASA’s Ames Research Center in Moffett Field, California.

The treasures kept coming. In March 2015, Cassini scientists detected silicate grains in the plumes – particles that most likely formed in reactions at hydrothermal vents.

By September, measurements of how Enceladus’s outer crust slips and slides had convinced them that it contains a global ocean between 26 and 31 kilometres in depth. That’s a paddling pool compared with Europa’s, but way deeper than Earth’s oceans.

So when do we visit? NASA has already selected instruments for a new mission to Europa, set for launch in June 2022. It will feature a magnetometer to probe the ocean’s saltiness and ice-penetrating radar to show

“ What could be bending Jupiter’s magnetic field around Europa?

Seawater fits the bill”

top four and previous: NASA/JPL-Caltech/Space Science Institute

that Hand suspects might be replicated on icy moons orbiting distant gas giants. “In my head, I was saying to myself: this is what it might look like,” he says.

Jupiter’s moon Europa, and Enceladus, which orbits Saturn, both have vast oceans secreted beneath their frozen outer shells.

As such, many astrobiologists consider them our best bet in the search for life beyond Earth.

NASA is plotting life-finding missions there.

But we don’t have to wait to dip our toes in extraterrestrial waters.

Having explored extreme ecosystems on our own ocean floor – places like Lost City, where life is fuelled by nothing more than the reaction between rock and water – we know what to look for. Now the race is on to spot signs of similar geochemical rumblings on Europa and Enceladus, and so discover whether we truly are alone in the solar system.

“Follow the water” has long been the mantra in the search for life, and for good reason: every known organism needs water to survive. Most prospecting has been done on Mars, but the Red Planet’s water is either long gone or locked in the ground as ice. These days, even Mars buffs would struggle to deny that the best prospects for finding living extraterrestrials lie further from Earth.

It might seem odd to search for liquid water in places far from the sun’s warmth. And yet it looks as if there are sloshing oceans beneath the surfaces of Europa and Enceladus, thanks to tidal flexing as a result of their eccentric orbits. As the gravity of their host planets pushes and pulls at the moons’ interiors, they warm from the inside out – and that heating is enough to maintain a layer of liquid between their rocky mantles and icy crusts.

The first hints of Europa’s concealed sea came from the Voyager probes, which explored Jupiter back in the 1970s. Voyager II spotted cracks in Europa’s icy surface crust, suggesting active processes below. When the Galileo spacecraft returned in the 1990s, it saw another clue: Jupiter’s magnetic field lines were bent around Europa, indicating the presence of a secondary field. The best explanation is the presence of a global vat of electrically conductive fluid, and seawater fits the bill. We now think this ice-enclosed ocean reaches down 100 kilometres. If so, it contains enough salty water to fill Earth’s ocean basins roughly twice over.

The case for a sea on Enceladus washed in more recently. In 2005, the Cassini probe showed that the moon leaves a distinct impression in Saturn’s magnetic field, indicating the presence of something that

Two of Saturn’s moons may host life: Enceladus (with its geysers) and Titan (bottom right)

where solid shell meets liquid water. It might even include a lander to fish for amino acids, the building blocks of the proteins used by every living thing on Earth.

The space agency has also invited proposals for a trip to Enceladus. One option is the Enceladus Life Finder, a probe that will sample plumes using instruments capable of detecting larger molecules and more accurately distinguishing between chemical signatures. Other plans have even suggested carrying samples back to Earth for analysis.

With any luck, NASA probes will be arriving at these ocean worlds by the twilight years of the 2020s. Until then we just have to sit tight, daydreaming about what fresh wonders we might find once we get there. Or do we?

In fact, there is plenty we can do in the meantime to plumb Europa and Enceladus’s hidden depths. We can survey their surfaces using ground-based telescopes, gawping at the fissures where water might bubble through and leave telltale deposits from the oceans

beneath. We can model the geophysics that keeps them liquid so far from the sun, and may generate conditions that could support life. And we can use the closest analogues on our own planet to guide our search.

On Earth, deep-sea vents at the boundaries between tectonic plates, where magma breaches the sea floor, have long been recognised as hotbeds for life. Around geysers of scalding, murky water – known as black smokers – bacteria feed on chemicals, and all manner of organisms make their living on those microbes. Europa or Enceladus might just draw enough energy from the tidal push and pull of their host planets to have molten interiors that can fuel similar vents. We don’t know. The good news for life hunters, however, is that we’re now aware of another possibility.

When we discovered the Lost City vents beneath the Atlantic in 2000, we saw that you can have a hydrothermal ecosystem with resident microbes and the occasional visit from a comb jelly – the otherworldly creature spotted by Hand during his visit – without the faintest rumble of tectonic activity.

Lost City is powered by a chemical >

The improbable promise of Titan Saturn’s largest moon, Titan, boasts glorious bays and beaches, but not a drop of liquid water. With temperatures

this activity, but the only way to know what causes it is to visit Titan. No such mission has yet been signed off, but recent work

forming larger ones made of carbon, nitrogen and hydrogen called polyimines – and these could form the backbone of an

hovering around -180 °C, it is far too cold for that.

The lakes and seas that dot its surface are instead filled with methane and ethane, which are gases here on Earth but slick, oily liquids in Titan’s frigid climes.

has given us fresh impetus by suggesting that the moon’s ice-cold chemistry would offer the toolkit required to make weird analogues of the molecules that support life on Earth.

In 2015, a team at Cornell

alternative biology.

At terrestrial temperatures, these chemical structures would fall apart. In the cryogenic seas of Titan, however, they would be preserved and could take on a wide array of forms, some of

This makes Titan an unlikely focus in the search for new forms of life in the solar system (see main story).

Astrobiologists have speculated that any life there might run on an entirely alien chemistry. Some suggest that microbes could make a living by breathing hydrogen and eating organic molecules like acetylene and ethane. The Cassini probe has spied evidence of chemical activity in Titan’s atmosphere that seems consistent with the idea.

There could, of course, be

University in Ithaca, New York, constructed a flexible, cellmembrane-like structure using only the ingredients and conditions available on Titan.

Earlier this year, Martin Rahm, also at Cornell, and colleagues did some modelling to show that Titan should possess the chemicals required to create even more complex molecules.

Hydrogen cyanide is abundant in Titan’s atmosphere and should rain down on the surface, but it doesn’t appear to build up there. Instead, Rahm suggests, hydrogen cyanide combines with

which could carry out primitive versions of the reactions in living cells here on Earth. Rahm says they might even float to the surface of tidal pools as membrane-like films, or as mats of stacked, crystalline molecules.

It’s another leap for any such system to be truly alive – to metabolise, replicate or evolve. Even so, given that these chemicals can absorb light at the very wavelengths that penetrate Titan’s cloudy atmosphere, any hungry organisms lurking in its methane seas would at least have a few rays of sunshine to

non-biological explanations for

other molecules when it lands,

snack on.

13 August 2016 | NewScientist | 31

NASA/JPL/DLR

reaction called serpentinisation. When alkaline rocks from Earth’s mantle meet a more acidic ocean, they generate heat and spew out hydrogen, which in turn reacts with the carbon compounds dissolved in seawater. It is these reactions that slowly built the towers of carbonate, some 60 metres tall, that disgorge organic-rich alkaline fluids into the water and make methane for microbes to snack on.

According to Michael Russell, a geologist turned astrobiologist at JPL, Lost City is just the sort of place where life on Earth might have begun. Russell thinks that the imbalance between the alkaline fluid flooding cell-like pores inside carbonate chimneys and the relatively acidic seawater beyond created electrochemical potential that the molecular precursors of life found a way to tap. If he’s right, then wherever alkaline hydrothermal vents exist life may have followed.

Astrobiologists like Hand think there is a good chance we’ll find them on Europa and Enceladus. Now they are attempting to confirm their suspicions from afar.

One way to do that is to look for molecules whose presence would betray ongoing serpentinisation. Cassini’s discovery of silicate grains in Enceladus’s plumes suggests this reaction has at least happened there in the past. Recent estimates suggesting that the ocean itself is rather alkaline, which would be expected after eons of serpentinisation, add to the case. To figure out if the process is

“ HIDDEN OCEANS could be THE DEFAULT state FOR LIFE to arise, with earth THE real OUTLIER”

happening today, however, we want to see hydrogen. That would be important because where there are free molecules of hydrogen gas in the deep sea, there tends to be life.

“Hydrogen is chocolate-chip cookies for microbes,” says McKay. Although Cassini was not built to detect molecules as large as amino acids, the probe could detect small molecules like hydrogen. In fact, that is precisely what it was attempting to sniff out late last year, during its penultimate dive through the plumes; mission scientists are still analysing the data. But it will be tricky to distinguish between the possible sources of any hydrogen molecules they find. The trouble is that hydrogen in the plumes could

Sea change Our planet's oceans are clearly visible from afar. But elsewhere in the solar system, seas hide beneath the frozen surface of moons – which might make them friendly to life

Surface ocean Average water depth Total water volume

EUROPA 3.6km 1.39 billion km3

Life on Earth could have begun at undersea alkaline hydrothermal vents, where seawater and rock react to generate energy

32 | NewScientist | 13 August 2016

Moon of Jupiter

Subsurface ocean Estimated water depth Total volume

100km 3 billion km3

Anomalies in Jupiter’s magnetic field suggest it contains a global subsurface ocean with a vast area of rock in contact with water

ENCELADUS

Moon of Saturn

Subsurface ocean Estimated water depth Total volume

26-31km Unknown

Plumes from Enceladus’s south pole indicate a global sea beneath its icy shell. Their chemistry also hints at hydrothermal activity

SOURCE: NASA/JPL/USGS

EARTH

for life as we know it: electron-grabbing oxidants like oxygen and electron-giving reducing agents like hydrogen have to meet and react, releasing energy that living things rely on in the form of electrons.

Europa has no atmosphere from which to cycle oxygen, as Earth does, but we know that radiation from Jupiter produces oxidising chemicals on its surface. To arrive at their conclusions about Europa’s sea, Hand and his colleagues assumed that these oxidants are being cycled from surface to sea.

Life, cycled

Lost city expedition/NSF

either be from serpentinisation or from water split apart in the atmosphere, after it was launched from the surface. If it turns out to be the former, it would be a big deal – the strongest indication yet that hydrothermal vents at the bottom of Enceladus’s ocean are serving up good amounts of chemical fuel.

There may also be other clues in Cassini’s back catalogue. The probe flew through the plumes so fast that it broke apart larger compounds, and we might be able to use its detection of the fragments to reconstruct the big stuff. “There are clearly some aromatics in some of these heavier compounds,” says Hunter Waite at the Southwest Research Institute in San Antonio, Texas. But aromatic compounds can be produced through either biological or abiotic processes, so its presence wouldn’t be a smoking gun. Still, it would help us understand what kinds of carbon chemistry can flourish under the ice.

Europa is even more likely to have serpentinisation as it is much larger, meaning it boasts more rock in contact with seawater.

There are no confirmed plumes to sample, though. Instead we are learning about its ocean chemistry by peering at its surface from telescopes on Earth. In October 2015, for example, observations made with the Keck Observatory in Hawaii revealed a strangelooking substance in a region of Europa riddled with cracks. Although the chemical signature suggests it could be dirty water ice, the dirty part has so far defied identification.

Patrick Fischer of the California Institute of Technology in Pasadena, who led the analysis, says the deposits could be potassium chloride or sodium chloride. Both are normally transparent but could be rendered visible by the shower of energetic particles raining down from volcanoes on Io, Europa’s explosive sister moon. If so, we could be looking at salts left behind after underground water breached the surface and then evaporated. That would suggest the ocean is seasoned not with the sulphate salts from Io, as most people expected, but with chloride – making it perhaps a third as salty as expected and therefore friendlier to life.

This May, Hand and his colleagues made a bigger splash with a study suggesting that Europa’s ocean has a chemical balance similar to Earth’s. The calculations were based on estimates that fractures in the moon’s sea floor could reach as deep as 25 kilometres into the rocky interior. In that case, there would be great swathes of rock surface with which water can react to release lots of hydrogen.

But that is just one part of a cycle required

Life-giving chimneys like those at Lost City, under the Atlantic, could exist on Europa

That’s a big assumption. “If you mix the subsurface and the surface, then you get a chemical cycle that life could take advantage of,” says Britney Schmidt, an astrobiologist at the Georgia Institute of Technology in Atlanta.

If not, life is unlikely. And it’s not yet clear whether that cycling happens on Europa, never mind Enceladus, where the radiation from Saturn is weaker, leaving fewer oxidants on its surface.

To find out, Schmidt has drilled through Antarctic sea ice and deployed a robotic submarine to study the underside, where fresh ice is constantly forming and melting.

“If we can figure out how the ice and ocean system works here on Earth, then we can extrapolate back to Europa,” she says. Only then will we know if its vast ocean gets enough oxidants to create the ratio of elements for life.

It is possible, of course, that life elsewhere follows a different rulebook, that it is made from a different set of biochemical building blocks. So what should we be looking for if not organic molecules and amino acids? It is a question that astrobiologists contemplate, but it can probably only be answered by finding alien life forms.

Maybe we never will. Maybe we really are alone in the solar system. If we can detect something akin to deep-sea alkaline vents on faraway moons, however, the odds of finding extraterrestrials would be slashed.

We might also have to entertain the prospect that similarly life-friendly conditions are lurking beneath the shells of other icy worlds: moons like Ganymede, Mimas and Ceres. In fact, given how common we now know them to be, oceans concealed by frozen crusts could be the default condition for life – in which case our blue planet, with its peculiar open oceans, is the outlier. n Joshua Sokol is a science writer based in Cambridge, Massachusetts 13 August 2016 | NewScientist | 33

ron kurniawan

34 | NewScientist | 13 August 2016

Fatal fungi We overlook a mushrooming threat at our peril, finds Tim Vernimmen

S

OME are tasty, others are a nuisance.

That’s probably how most of us think of fungi. Few people would consider them to be killers. But perhaps we should.

Fungi are on the march. New varieties are emerging and infecting everything from crops to amphibians. Some of this is down to the ease of international travel, which is spreading hardy spores to new locations. Then there’s our disruption of natural environments, which creates opportunities for fungi to evolve. Now, some researchers are worried we could be about to reap the spores we’ve sown: might we have unleashed a killer?

Neil Gow, a medical mycologist at the University of Aberdeen, UK, was co-organiser of a conference held at London’s Royal Society earlier this year to assess the growing fungal threat in areas from animal welfare to food security to ecosystem stability. He’s keen not to overstate the threat to human health – but not to downplay it either. “I don’t think a fungal pandemic is imminent: as far as we know, humanity has never been struck by one,” he says. That is not to say fungi don’t kill people. “More people die from invasive fungal infections than from malaria, a disease we hear much more about.”

Even now, about a dozen fungal species kill in total around 1.5 million people every year.

Fungal disease is a significant contributor to AIDS deaths, for example – and yet the threat is often overlooked. “Fungal and bacterial infections may give similar symptoms, leading to misdiagnosis,” says Gow. “So in many cases, patients with fungal infections are initially treated for bacterial infections instead.”

Fungi comprise a whole kingdom of organisms in their own right, separate from plants and animals, and far less studied. This hugely diverse group of up to 5 million species includes mushrooms, yeasts, moulds and

crop-destroying rusts and smuts. Most of the time, we happily coexist even with the killer varieties – you may be inhaling them right now, or they may be living in or on your body.

But occasionally they turn rogue.

Take Candida albicans, which causes most fungal infections in humans. Candida cannot survive without living on us or other animals.

“There’s no evidence that it’s doing us any good, but it usually doesn’t harm us either,” says Gow, who studies Candida. Yet sometimes the unassuming resident gets a bit too comfortable and multiplies so fast that it causes the infection commonly known as thrush.

How and why this happens is the focus of intense research. Usually, our white blood cells and other defences do a good job of keeping the fungus under control. “But anything that tips the odds the other way,” says Gow, “such as low numbers of white blood cells or antibiotics that wipe out other microflora,

“ More people die from invasive fungal infections than from malaria ” may cause a local outbreak.” This can be very aggravating – just ask one of the 100 million women worldwide who suffer at least four episodes of vaginal thrush a year. Most people recover without complications, because the fungus seldom thrives in the blood.

“The bloodstream of a healthy human is quite robust to infections,” says Gow. But Candida does overcome the defences of hundreds of thousands of people each year to enter their blood – and at least half of them die. How can this be? “In a way, fungal infections are the disease of the diseased,” says Gow. “People who are vulnerable after an accident or invasive surgery, or whose > 13 August 2016 | NewScientist | 35

36 | NewScientist | 13 August 2016

E. GUEHO/SCIENCE PHOTO LIBRARY

DAVID SCHARF/SCIENCE PHOTO LIBRARY

immune system has been weakened or suppressed after an organ or stem cell transplant, may be unable to fend off a fungal attack. Candida is very opportunistic.”

To work out a way to help the immune system nip Candida in the bud, Gow and his colleagues are investigating how the fungus interacts with our white blood cells. “It’s a titanic struggle on a microscopic scale,” he says. Candida uses camouflage and can shed tiny bits of cell wall to avoid being caught.

Even when it does end up inside a white blood cell, it’s not game over. “The fungus can evade digestion by reducing the acidity inside the cell compartment where it’s held, and it even scavenges some of the cell’s food,” says Gow – “which is why it’s often able to keep growing until the white blood cell bursts open.”

Another potentially deadly fungus, Cryptococcus, can cause meningitis by lurking in a white blood cell until it crosses the usually impenetrable blood-brain barrier. It then forces the cell to eject it.

Unlike Candida, Cryptococcus is not a fungus native to us – instead, it usually grows on rotting plant material in the soil. “Though most of us have been exposed to it by the age of 6, the chance that a particular Cryptococcus cell has encountered a human before is absolutely minuscule,” says Robin May at the University of Birmingham, UK. Yet Cryptococcus has recently achieved something once considered almost impossible: it has infected and killed previously healthy people.

First discovered in Vancouver, Canada, over a decade ago, a particular strain of Cryptococcus, C. gattii, spread across the Pacific Northwest of the US, killing hundreds along the way. How does a fungus living on plant matter manage to survive inside a healthy human body? By accident, argues May. “There is obviously very little evolutionary pressure on Cryptococcus to find a way to survive in humans,” says May. However, the fungus is preyed upon by amoebas in the soil, and their mode of attack is quite similar to that of white blood cells. That might give the fungus a head start. This means it can occasionally thrive inside the body, harming its host in the process.

Like Gow, May doesn’t think a fungal pandemic is just around the corner. “Fungi have very complex life cycles, and they tend to grow and evolve much slower than bacteria or viruses do.” The fact that fungi don’t depend on us for their survival cuts both ways, though. “It means that they probably aren’t trying very hard to conquer us. But also that

they couldn’t care less if we were all to die.”

Given that there has only been a single outbreak of C. gattii, it’s difficult to establish what led to it. May surmises that the strain had been around for some time, and that a very hot and dry summer may have contributed to its spread. “The fungus likes humid soils, so perhaps the drought stimulated it to produce more spores, or simply provided conditions that helped them to blow around more,” he says. However, we don’t have clear evidence for this and May notes that the summers of the past decade have all been fairly wet.

FUNGAL HELPERS Although a few fungi can kill us, many provide indispensable services. l Fungi play a crucial role in ecosystems by feeding off organic matter and

recycling the nutrients for plants to use. l Yeasts are vital in the fermentation

of sugars to make alcohol and for leavening bread. l Fungi produce antibiotics, most

famously penicillin, and are used to make other drugs – even antifungals. They also synthesise complex compounds of commercial value, including ingredients

for perfume. l We can use fungi to tackle oil spills, break down pesticides and herbicides, and destroy neurotoxins used in chemical weapons. l The birch polypore mushroom even makes a good hat.

This raises the question of whether other deadly new fungal strains might emerge as climate change takes hold. That is difficult to answer because the impact on weather patterns is likely to be very variable, says May. “But you might expect, for example, that Britain, which is a bit too cold for many fungi right now, may see an influx of fungus when temperatures rise.” Another concern is that although the warmth of our body protects us from many fungal infections, a warmer world may undo that by helping fungi to adapt. “But I currently know of no studies showing that fungi from warm soils infect warm-blooded animals more easily,” says May. In any case, Cryptococcus copes just fine with being at 37 °C. Another fungus, called Aspergillus, can live in the heart of compost heaps at temperatures of 60 °C. Aspergillus spores are absolutely everywhere, says Jacques Meis of the Canisius Wilhelmina Hospital in Nijmegen, the Netherlands. “Every breath you take, they’re infecting you.”

Garden-variety killer In the early 1990s, Meis was a parasitologist working on malaria when a prominent Dutch haematologist sought his help. “We can now treat blood diseases with bone marrow transplants or cycles of chemotherapy, but then patients literally die of garden-variety fungal infections,” he told Meis. Keeping Aspergillus at bay is a constant challenge.

“The fungus and its spores are really small and often very water-repellent, so they take off with the slightest air current and find their way through all but the finest air filters,” says Meis. They are also extremely hardy – the spores can survive acidity, dehydration,

EYE OF SCIENCE/SCIENCE PHOTO LIBRARY

A handful of fungi kill some 1.5 million people each year.

They include (from left to right) Candida, Cryptococcus and Aspergillus

Deadly fungal disease is often not viewed with the seriousness it deserves because it mainly affects people that were “on the way out anyway”, says medical mycologist David Denning at the University of Manchester, UK, But that argument is very problematic, he says. “The Cryptococcus gattii outbreak shows that there is always a risk that a fungus will one day find a way to infect healthy people as

KOH OKAMOTO, SHUJI HATAKEYAMA ET AL.

One deadly fungal strain has found a way into the human brain

EDMOND BYRNES AND JOSEPH HEITMAN/DUKE UNIVERSITY

freezing and high heat. No wonder they’re the most common eukaryote on the planet.

Eukaryotes – which include fungi but not bacteria or viruses – are organisms in which the cells contain a nucleus. The fact that we, too, are eukaryotes makes it difficult to combat fungal pathogens. “Some of the most effective medicines against fungal infections, such as amphotericin B, are quite toxic to our cells as well,” says Meis. So they are often combined with or replaced by another class of antifungal drugs, collectively known as azoles.

“The azoles block an enzyme that most fungi need to maintain their cell membrane,” he says.

You would expect fungi to develop resistance to these drugs in people receiving repeated or long-term treatment. But lately, Meis has seen an increasing number of patients coming down with a resistant strain right away. “We found this very odd at first,” he says. “But then it dawned on us that in the past decades, azoles have become very popular products.” They are now used to prevent fungal growth on crops, produce and flowers, and are an ingredient in many paints and coatings. Aspergillus isn’t the target of these azoles, but it is constantly exposed to them. “There is no doubt that some of these applications are contributing to azole resistance in the clinic,” says Meis. “Because Aspergillus is quite literally all over the place and exchanges genes very quickly, resistance can spread across the world incredibly fast.”

Meis doesn’t expect companies to stop producing azoles or farmers to stop using them. “I’m afraid the fact that Aspergillus targets only patients who are already weak will likely undercut any arguments in favour of reduced azole use,” he says, “except if we can figure out which products are causing the biggest problems and why.”

well.” In any case, it isn’t true that weakened patients who contract a fungal disease are already bound to die of some other cause, says Denning: our ability to keep severely ill people alive is constantly improving. However, this means the number of people vulnerable to fungal disease will go on rising unless we tackle the problem. “It would be a terrible shame if this progress and all we’ve invested in it were offset by fungal infections.”

Yet that is what is happening, especially in the fight against HIV. Antiretroviral cocktails are now highly effective, but many people with HIV live in poor countries where it can be difficult for them to take the drugs as prescribed. A lapse in treatment can cause their white-blood-cell count to drop, at which point any fungus they’re exposed to may turn invasive. “About half of all AIDS deaths are the result of fungal infections,” says Denning, “yet they’re hardly addressed.”

There are multiple reasons why the problem is going untackled. “Diagnosis of fungal disease isn’t straightforward – it is as good as impossible without access to a medical lab – and treatment with amphotericin B is intravenous and risky,” says Denning.

But the task isn’t impossible, and cracking it could be a big step towards achieving the UN’s target of reducing annual AIDS-related deaths to below 500,000 by 2020. “If we could treat 60 per cent of the HIV patients annually overcome by an invasive fungus, we could save at least 300,000 lives a year – typically 35year olds, economically active, with husbands or wives and children who need them,” he says. “These people aren’t on the way out.

They are ill, and they need our help.” n Tim Vernimmen is a writer based in Antwerp, Belgium 13 August 2016 | NewScientist | 37

Brent Stirton/Getty Images

We risk our lives daily for this park Emmanuel de Merode shares his plan to bring peace to Africa’s embattled Virunga National Park, and good news about its critically endangered mountain gorillas You’ve called Virunga a magical place. What makes it so enchanting?

It was established in 1925 as Africa’s first national park. Virunga is one of the most spectacular landscapes on Earth because of the extremes in altitude, from a low of 900 metres above sea level to active volcanic peaks at 4500 metres. In between is an incredible diversity of habitats and species: you travel 38 | NewScientist | 13 August 2016

a few kilometres and everything changes, from classical acacia savannahs, to lakes and wetlands, to alpine zones. It is a microcosm of virtually all the ecosystems found in Africa.

It is also one of the parks most affected by war.

That’s true. There have been four major wars in the Democratic Republic of the Congo since 1996. In a sense, all of them started

within Virunga National Park. The park is in the DRC but touches the borders of Uganda and Rwanda. These three countries have been swept by armed conflict in recent decades.

The park has extensive forests that serve as refuges for militias and a source of the natural resources that they traffic to fund themselves.

There is $35 million of illegal fishing on the park’s Lake Edward every year, an equal dollar amount in illegal charcoal production, and illegal appropriation of park land for agriculture. The militias are involved in all of these activities. There are 12 distinct militia groups operating in Virunga right now.

You were shot and seriously injured in 2014, and nearly 150 of your rangers have been killed in two decades protecting the park. Yet few of your rangers quit. Why is that?

I’m not sure, to be honest. The chance of dying a violent death during your service here is 35 to 40 per cent. I don’t think there are any armies on earth with our level of casualties, or that have had their soldiers under combat

PEOPLE

Profile Emmanuel de Merode is an anthropologist, conservationist, a prince of Belgium and the director of Virunga National Park in the Democratic Republic of the Congo

as a means for survival. If you can provide them with an alternative livelihood, you go a long way to fostering stability and peace.

But you have to create jobs on a large scale.

To do that, we need to look at the resources that the park can offer the community to provide employment, while safeguarding its environmental integrity.

You’re aiming to use national park revenues to create 60,000 to 100,000 jobs in your area in the next decade. What initiatives could help achieve this goal?

One project is to create eight hydroelectric plants outside the park boundaries. We’ve found that when you build such plants, you quickly get many small and medium-sized enterprises springing up around them, mainly small agribusinesses such as flour mills, cold-storage facilities and soap manufacturers. A pilot project has shown that you can create 800 to 1000 jobs for every megawatt of electricity that you bring to a community.

The traditional model of conservation says: “this is a protected area, so you can’t do anything in it”. Your vision is clearly different.

conditions every day for the past 20 years.

It’s incredibly stressful. But on the other side, you have a strong feeling of cohesion within the community of rangers. Many are the sons and daughters of rangers: sometimes even their grandparents and great-grandparents worked here, so there’s a real sense of shared values and mutual support. If I were to up and go, I would feel like I was letting them down, so that’s extremely motivating in terms of committing oneself to the park and the team.

You helped negotiate agreements between rebel factions and the DRC government to spare the park, and have called Virunga a stabilising force for peace in the region. In what sense?

The underlying causes of the armed conflict are economic. We have an unemployment rate of 70 per cent in our region, and 4 million people live within a day’s walk of the park boundaries. When you have that population size and level of unemployment, combined with the availability of small arms, it’s no surprise that young men choose the militias

It has to be. The resources of the park must be used to economically uplift the local people.

This is very fertile and valuable land that’s worth about $1200 a hectare per year. With an area of 800,000 hectares, that means about $1 billion a year is being forfeited so the park can be maintained.

The park is for the whole of humanity, but the cost is almost entirely borne by local people, who lose the right to these lands due to conservation. The sacrifice by some of the poorest people on earth is an extreme case of environmental injustice. So we have to find alternative forms of economic growth to generate that level of income for the local community. That’s the only way to prevent the park being destroyed in the long run.

that great. But the point is that it helps to break the eastern DRC out of its isolation.

For example, we built a lodge at the park headquarters in Rumangabo about five years ago. The lodge itself hasn’t been a huge boon to the economy, and we didn’t expect it to be. However, it brought investors as well as tourists to the region. And because of that, we managed to secure $60 million in investment around the park, particularly in the energy sector. So tourism isn’t just about tourists – it’s a kind of pioneer activity that creates inroads into a region that can also be used by investors, helping to build the economy.

The mountain gorillas are tourist favourites.

An ongoing survey is expected to report rising numbers in the park and adjoining reserves.

That’s amazing for a war-torn region, isn’t it?

It’s quite remarkable. The DRC, Rwanda and Uganda have all been intensively protecting these animals, even during times of armed

“ The gorillas embody some of humans’ best traits – they welcome you to the family” conflict. Here in Virunga, only two gorillas have died in snares set out by bushmeat poachers to catch other species since 2007, in a period when there have been dozens of births. So yes, we expect the survey to show a significant rise in gorilla numbers.

How do you feel about these gorillas?

They embody some of the best traits of humans. They form very tight-knit and highly stable family units, and their interactions with one another are very intimate and warm. They extend that to humans as well, so it’s as if they welcome you to the family when you are with them. They are a very endearing species.

Do you have any favourites?

Tourism is one way to help the local economy, but is it correct that money from tourist lodges doesn’t always flow to the surrounding communities?

Kabirizi is a stunning male who dominates his group. He is not used to humans, and is much more nervous and more feisty than others, but he’s quite a lot of fun. There is another silverback called Humba. He’s huge – the biggest silverback of all – but he’s very calm, gentle and easy-going. They’re both wonderful, and they represent two ends of the spectrum in terms of personality. That individuality is what makes it so interesting and entertaining being around gorillas. We simply have to save this species! n

You’re right; the volume of tourist money injected into the community is not necessarily

Interview by Richard Schiffman 13 August 2016 | NewScientist | 39

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culture

The Marconi connection He may not have had the originality of Einstein, but we still owe Marconi a huge debt for his intuition, finds Andrew Robinson

AT GUGLIELMO MARCONI’s grand state funeral in Rome in 1937 – orchestrated with military-style pomp by the black-shirted Benito Mussolini – the largest wreath on the hearse, adorned with a Nazi swastika, was sent by Adolf Hitler.

As the funeral began (6 pm precisely, Rome time, on 21 July), telegraph and radio stations in Italy, the UK, the US and Canada fell silent. As did the 31 beam and wireless stations of Cable and Wireless’s global network, and others in China, Japan, the Middle East and Europe.

Everyone knows that Marconi was the main pioneer of wireless communication. Yet we are far less confident about just which parts of this invention were his own work, in contrast with the inventions of near-contemporary, Thomas Edison. Now, at long last, we are offered a clearer picture in Marconi: The man who networked the world, a deeply researched and almost all-encompassing biography by Canadian media studies academic, Marc Raboy.

Fascinating and influential though Marconi was, the man who emerges does not inspire warmth, either in Raboy or, perhaps, in most readers of his notably balanced book. As Marconi remarked in 1934 in an 42 | NewScientist | 13 August 2016

exchange with the principal of the University of St Andrews, UK, after the students elected him lord rector: “Have I done the world good, or have I added a menace?”

Radio transmission is one of the great inventions of all time. But in Raboy’s view, “Marconi’s greatest invention was himself”. Most of his massive biography is therefore devoted not to wireless science and technology per se but to its profound ramifications for national and international business and politics, and for the complicated identity of Marconi. including the attack on what He was a man full of inner is now Ethiopia in 1935, when dissatisfaction, a womaniser Marconi offered to serve in Africa. with generally troubled personal In his later years, he spent much relationships, including a failed time on the yacht he bought in marriage. Among men, Marconi 1919: a floating lab he named “didn’t really have friends, only Elettra, after electrum: the Latin associates”, remarks Raboy. By for amber, which creates a spark contrast, “He courted women who when rubbed. challenged him but married two In the mid-1920s, Marconi’s who would never have dreamed company started short-wave radio of doing so.” Raboy concludes: transmissions using the so-called “Something was missing…

Marconi beam system. These perhaps a result of his mother’s rapidly supplanted the cabled unconditional devotion; he telegraphy introduced in 1830s, always, painfully, sought and and led to the global connection was never able to find that in a “Fascinating and influential companion.” though Marconi was, the A permanent outsider who man who emerges does longed to belong, Marconi was not inspire warmth” born in Italy in 1874 to an Italian Catholic father and an Irish Protestant mother, made his we take for granted in our mobile name and fortune in imperialist telephony and the internet. The Britain at the turn of the century, beam concept was Marconi’s, but and became a visiting celebrity in its key technology was an antenna the US and Canada. He eventually designed by Charles Franklin, his returned to Italy to embrace employee, close colleague and Mussolini and Italian fascism, collaborator, who went on to Science & Society Picture Library

Marconi: The man who networked the world by Marc Raboy, Oxford University Press, £25 Museum of the History of Science, Oxford: Director’s Choice by Silke Ackermann, Scala Arts, £9.95

design the antenna for the first BBC television transmission in 1936.

After Marconi’s death, Franklin wrote of his boss with a mixture of respect and criticism: “His scientific knowledge was weak, his engineering knowledge was weak, but he had a damned lot of intuition and common sense.

He may have initiated the beam system but he didn’t know a thing about it.”

Franklin’s analysis certainly applies to the most famous episode of Marconi’s tumultuous career. It was 1901 and Marconi was in Newfoundland, waiting for a signal to cross the Atlantic from a spark transmitter in Cornwall, UK. At that time, physicists were convinced by the electromagnetic theory of James Clerk Maxwell and unaware of the existence of the reflecting ionosphere. They were sure that such long-distance atmospheric transmission was impossible because all electromagnetic waves travelled

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in straight lines, like light beams, and could not bend to follow Earth’s curvature. Marconi ignored conventional wisdom and ploughed on with his experiment.

As Raboy writes, his “tinkerer’s experience… made it happen by following hunch and intuition rather than scientific theory”.

But, as with his later beam system, a crucial element in Marconi’s 1901 equipment was not his invention: the sensitive detector known as a coherer.

Originally conceived by French physicist Edouard Branly in 1890, Marconi’s 1901 coherer was created by an Italian collaborator, Luigi Solari. He apparently based it on an unpatented mercurybased design by Indian physicist Jagadish Chandra Bose, published in the Proceedings of the Royal Society in 1899: a borrowing never acknowledged by the notoriously litigious Marconi and neglected,

Shiver our timbers!

Henry VIII’s favourite warship lives, thanks to 21st-century tech, finds Chris Simms The Mary Rose Museum, Portsmouth, UK

THE watch bell rings out amid the hubbub of the ship. Sailors work on deck; the barber-surgeon yanks a tooth; men cook for their 500 shipmates. As the enemy approaches, everything changes: cannons are primed, archers loose arrows. The 16th-century warship is alive in a way it hasn’t been since it sank in 1545, battling the French.

On view again after a six-month hiatus, the Mary Rose is now lit with CGI vignettes. Move along glass-panelled viewing platforms parallel to the remaining half of the ship and sound effects change to match the videos. Thousands of preserved objects from Henry VIII’s favourite warship also give us an unrivalled look at Tudor life.

But it is much more than that.

The fact we can now see it close up and breathe the air surrounding its ancient timbers is a testament to an epic conservation effort dating back to 1982 when the ship was raised from the Solent.

Mary Rose 2016: CGI, sound effects and timber smells bring it to life

Waterlogged and home to marine bacteria and fungi, if the ship dried too fast, it would crack and collapse, so for 12 years it was sprayed with chilled water. Then, from 1994 to 2013, it was doused with polyethylene glycol, while a biocide killed bacteria and fungi.

So why does the ship look so dry now? Since 2013, dehumidifiers have sucked tonnes of water from the hull, bringing it to a stable state that should last many years.

Look carefully and you may see signs of another conservation battle: yellowish traces of iron and sulphur in the wood. The ship was held together by iron nails and wooden pegs. The nails rusted, forming iron oxides. When the ship was below the sea, anaerobic bacteria used this oxidation for energy, producing hydrogen sulphide, which is acidic in water, further weakening the timbers.

Hence why the frame supporting the hull is titanium not iron.

The Mary Rose is not just a Tudor time capsule. It was crewed by microbes and skeletons for 437 years, and has been out of the water for as long as it sailed. Its voyage is still going on. n

stephen foote,courtesy of the mary rose trust

Marconi followed his intuition rather than scientific formality

surprisingly, by Raboy.

Marconi’s very first coherer, undoubtedly based on Branly’s, caused a sensation when he demonstrated it in public lectures

by William Preece, the engineerin-chief of Britain’s Post Office in 1896-1897. Concealed in a black box with an electric bell on top, the coherer could receive a signal from a spark transmitter that rang the bell, no matter where Marconi placed the black box, and without any visible connection between transmitter and box. There was immediate talk of “magic”, and comparisons with illusionist Harry Houdini. Even the University of Oxford called Marconi a “magician” in a speech conferring an honorary degree on him in 1904.

The coherer, now in the extensive Marconi collection at the Museum of the History of Science in Oxford, is reproduced in a new, superbly photographed guide to the museum. It is one of 35 intriguing objects taken from the museum’s collections, appealingly described by its director, Silke Ackermann.

These objects range from a metal astrolabe constructed by Muhammad Muqim al-Yazdi for Shah Abbas II of Persia in 1648 to a paper “photogenic drawing” John Herschel made in 1839 and a flask of penicillin culture made by one of its developers, Howard Florey, around 1940 – plus a blackboard chalked by Albert Einstein in Oxford in 1931.

Marconi’s coherer certainly ranks with astrolabes, photography and penicillin. But as portrayed

by Raboy, the man seems to me much closer in intellect and personality to, say, Steve Jobs than to Einstein. Despite Marconi’s limited original contribution to technology and science, we shall always owe him an enormous debt for his vision of universal communication. n Andrew Robinson’s latest book is Einstein: A hundred years of relativity, Princeton University Press

13 August 2016 | NewScientist | 43

analysis brexit

The hell of uncertainty

NIKLAS HALLE’N/AFP/Getty Images

After the vote to leave the European Union, UK researchers need answers and action on funding, co-operation and freedom of movement, writes Jeremy Webb

–Lost souls

IN HIS Divine Comedy, Dante she must negotiate with EU names the first circle of hell officials, who will want what’s “limbo”. The virtuous pagans best for their members. stuck there can do nothing to Science has not been slow to improve their lot but await divine urge action on a broad set of intervention. Today, UK scientists priorities issued by the Royal find themselves in a limbo of their Society and other UK national own over their relationship with academies last month. the other 27 countries of the Academies want the European Union. government to commit to filling The cause is the UK referendum any gap in research funding vote to leave the EU – though created by Brexit. That’s no small admittedly, the intervention matter, given that the UK gets they await is not divine. First, the more out of the EU’s main science prime minister Theresa May must fund than it puts into it – about decide what she wants from the “ Theresa May wants to cut divorce settlement with the EU, immigration, which will put including the nature of the posther on a collision course exit relationship and future with science and Brussels” access to the single market. Then 44 | NewScientist | 13 August 2016

£1.40 for every £1 it pays in.

Academies also want the UK to adopt regulations that match the EU’s in areas such as clinical trials and data protection. Without this “harmonisation”, the country could face barriers to research and trade with its nearest neighbours.

On top of this, academies want EU and UK researchers to remain free to cross borders to do science in other countries, and to collaborate as freely as they do now. This is where the spaghetti is likely to hit the fan. May wants to cut immigration, which will put her on a collision course not only with science, but also with Brussels. Free movement of people is a founding principle of

the EU, so rejecting it will almost certainly toss the UK out of the single market, and could also cost it dear in terms of access to the EU’s flagship funding programme for research, Horizon 2020.

World-beating research requires collaboration and free movement. Scientists have always travelled to learn from the best and to discover new ideas and skills. In the process they build networks and can pave the way for new markets. The UK’s openness – especially as part of the EU – is one reason for its scientific success.

In April, the House of Lords select committee on science and technology concluded that “researcher mobility must be

protected if UK science and research is to remain worldleading”. “Unnecessary barriers to this mobility will weaken science and be to the cost of all nations,” says a statement from some 30 national academies across Europe.

The League of European Research Universities supports this principle too. Its secretarygeneral, Kurt Deketelaere, told New Scientist: “Cooperation in the past has been beneficial in both directions, for the UK and for continental Europe.”

The UK will probably be watching London and Brussels have also those negotiations closely. restated that the UK is still part It is hard to know if the of the EU and legally nothing has government will opt for associate changed. Moedas reinforced this, membership, though: the silence saying there was no need for from Whitehall is deafening. The researchers on the continent to European Commission is also sideline UK scientists in new saying nothing. This reticence collaborations. reached a climax on 25 July, when Still more reassurance is aimed UK science minister Jo Johnson at the 43,000 academic staff and and the European commissioner for science Carlos Moedas shared “ After the referendum, dozens of UK researchers a platform at the EuroScience Open Forum in Manchester. After reported prejudice against UK bids for EU funds” addressing a hall packed with worried scientists, they declined postgraduates from other EU to take questions and left. countries who work at UK It seems the best the UK universities, and to UK academics government and European working in the EU. The eligibility Commission can do for now of many to remain where they are is to issue reassurances over has yet to be clarified. In her letter, uncertainties caused by the vote May says: “Our research base is and their own indecision. Last enriched by the best minds from month, May sent a letter to the Europe and around the world – Royal Society and its former providing reassurance to these president Paul Nurse, who wants individuals and to UK researchers science to have a place at the working in Europe will be a Brexit negotiating table. “I would priority for the government.” like to reassure you about the But these people seem to have government’s commitment to become bargaining chips in the ensuring a positive outcome forthcoming negotiations. for UK science as we exit the Beyond the uncertainty, has European Union,” she wrote.

The science case is not about narrow self-interest, says Anne Glover at the University of Aberdeen and former chief scientific adviser to the president of the European Commission. It’s about new treatments for cancer and next-generation phone networks – and, indeed, “the interests of everyone in the UK and our future sustainable economy”, she says.

What are those close to the political world thinking? “It wouldn’t shock me if the UK came out of the single market in order to take control of its borders,” says Graeme Reid, professor of science and research policy at University College London and a former Whitehall science mandarin.

In that case, the best hope is to try to become an “associated country” – which would, for a hefty fee, give the UK access to Horizon 2020. Nations including Israel and Turkey have become associates without agreeing to free movement of people.

But there is a potential fly in the ointment. Switzerland was an associate and had agreed to free movement. Then, in February 2014, the country voted to tighten immigration controls and the EU revoked its status.

Switzerland has regained limited access to Horizon 2020, but must renegotiate its membership this year – and that is not a done deal.

Lieven Creemers © EU 2015

Swiss miss

there been any direct impact yet?

Mike Galsworthy of the pressure group Scientists for EU has been monitoring events. In the month after the vote, 378 researchers from around the UK reported back. Of these, 33 noted prejudice against UK bids for Horizon 2020 funds and 25 described cases in which foreigners had turned down a UK job or cancelled an application because of Brexit.

Another 86 said they or someone they knew planned to leave as a result of the referendum, and 35 cited rising xenophobia, including personal attacks.

“The overall message is that UK science has been hit overnight because it is suddenly less attractive to talent staying here and as a place for partnerships,” says Galsworthy. Switzerland saw this after its vote on immigration.

“We had an image problem,” says Martin Vetterli, president of the country’s National Research Council. Being a relatively small country, Switzerland needs foreign researchers, and when they stopped coming it struggled on the world stage.

What now? The Royal Society is monitoring overseas applications to its fellowship programme to see if the UK’s appeal is waning. It is also exploring the best paths and outcomes for negotiations with Brussels. Elsewhere, the science committees of both houses of parliament have launched inquiries into the consequences of Brexit, Galsworthy is planning more creative ways to spread the value of science to the public, and the Campaign for Science and Engineering is trying to ensure that May’s new ministers and departments know what’s at stake.

Will UK science escape limbo soon? That’s doubtful, given talk of years of negotiations ahead.

But by keeping up the pressure, it raises the chance of eventually ending up in a better place. n

Jeremy Webb is New Scientist ’s –Johnson greets Moedas editor-at-large 13 August 2016 | NewScientist | 45

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Bioinformatician: Molecular Informatics/Modeller At Unilever, we strive to develop and innovate products that are safe for our consumers, workforce, and the environment. We are also committed to the elimination of animal testing and are at the forefront of research into novel non-animal approaches for assessing consumer safety. An exciting opportunity has arisen for a Structural Bioinformatician to join our team in the Safety & Environmental Assurance Centre (SEAC), where we carry out safety assessments for all our products as well as supporting Unilever’s alternatives to animal testing programme.

The role primarily involves provision of bioinformatics expertise to SEAC Scientists particularly in the area of structural bioinformatics: analysis of protein-ligand interactions, docking (ranking/prioritization), molecular dynamics. In addition the Bioinformatician will contribute to the development and evolution of a platform that integrates and visualises data from different sources to build capability in predictive non-animal approaches for consumer safety.

As you will work in multidisciplinary teams, you will need strong written and verbal skills to enable you to communicate complex concepts to a broad audience. You will also need to be an excellent problem solver who is comfortable working independently.

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Imperial College Research Fellowships Imperial College London is delighted to invite applications for its Imperial College Research Fellowship scheme, to give outstanding early-career researchers an opportunity to develop independent research programmes. In 2017, we will be awarding up to 20 fellowships. Each one offers up to 4 years funding (stipend in the range of £36,070 to £41,110 per annum plus a generous contribution to research expenses). Fellowships are designed to provide freedom to focus on research: there are no obligatory teaching or administrative duties. Applicants will be encouraged to apply for additional sources of funding to allow them to strengthen their research programme.

Proposals will be accepted in all research areas active at Imperial College London.

Multidisciplinary projects are welcomed as are collaborations with The Francis Crick Institute https://www.crick.ac.uk/research/ Applicants will need to identify an Imperial academic staff member to act as their sponsor who will provide laboratory space, facilities and mentorship for the tenure of the fellowship. Candidates may be from the UK or abroad and will be normally expected to have no more than 4 years post-doctoral research experience in an academic environment at the time of application. Proposals will be judged primarily on the basis of scientific merit, track record of the applicant and potential for development of an independent research programme.

For more information and application forms see: www.imperial.ac.uk/jrf Informal enquiries to researchfellowships@imperial.ac.uk Deadline for proposals is 12 September 2016 (midnight BST) Committed to equality and valuing diversity.

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13 August 2016 | NewScientist | 51

LETTERS editor’s pick

The hazards of sex and of childbirth From Avril Danczak You report on UK doctors potentially warning of the risks of vaginal childbirth – as though it were a medical procedure (9 July, p 8).

Try this thought experiment.

Should we ask men to sign a consent form before they have sex? Surely men should confirm that they know the hazards of sex, including sexually transmitted infections, trauma to the penis and HIV transmission, to name just a few.

If their partner gets pregnant, sex will involve them in lifelong financial and emotional commitments.

It is just as absurd to suggest “consenting” to childbirth, which is also a physical and psychological event, not a medical “procedure”.

The doctors’ proposal is based on a 2015 UK Supreme Court case, which involved a woman with a chronic disease affecting pregnancy.

Why assume it is appropriate to extrapolate to every pregnancy?

And is evidence about risk sound enough to inform choice about childbirth? The UK’s National Institute for Health and Care Excellence (NICE) describes the available evidence as of low or very low quality.

Childbirth is not a consumer good, chosen after careful consideration of the risks and benefits. It is inherently unpredictable, variable and uncertain.

Manchester, UK

To read more letters, visit newscientist.com/letters 52 | NewScientist | 13 August 2016

letters@newscientist.com

Hurrah for that objective collapse!

From Paul Vann Hurrah for the work of Daniel Sudarsky and colleagues in advancing the case for objective collapse theory (OCT) in understanding quantum physics (16 July, p 30). Both the standard (Copenhagen) and the manyworlds interpretations of quantum mechanics are clearly bonkers in their respective requirements. The first demands sentient observers: there are too few of us, and in the beginning there were none. The second generates unreasonably large quantities of “reality”.

There is surely a Nobel prize in a box somewhere, waiting to be opened and awarded to the leading developers of OCT. Loddiswell, Devon, UK From Louis Barson Schrödinger’s cat is a visceral metaphor that helps some to engage with quantum physics and stimulates debate. But it’s not a fair representation of the Copenhagen interpretation.

I believe it represents a “straw man” argument, reflecting the intuitive dislike that Erwin Schrödinger and Albert Einstein had of certain elements of quantum mechanics. The box is full of “observation” that causes any superposition to decohere: the cat is observing the system throughout. If it is alive, the decay can’t have taken place. How anthropocentric – or mystical – is it to assume that only human observation has a quantumweirdness-killing quality?

London, UK From Jan Willem Nienhuys In the 1960s the theoretical physicist Nico van Kampen taught me that the Schrödinger cat conundrum was a nonproblem. The cat, or in fact any macroscopic object, consists of a huge number of particles: say

there are n. Each can be in many positions or states – say m.

The total number of states is nm which is beyond astronomical.

But what are the probabilities that the cat is dead, alive or in a superposition of dead and alive?

The superposition probability is, van Kampen said, an average of a huge number of small negative and positive contributions. In his words, the result is a number that is closer to zero than any other number in physics.

The probabilities that the cat is dead or alive each add up to 0.5.

So we get equal probabilities that the cat is alive or dead, and a probability very, very close to zero that it is in a superposition of dead and alive.

Waalre, the Netherlands

The economics of impact statements From Merlin Reader Canadian firm Nautilus Minerals commissions an environmental study on the proposed deep-sea Solwara 1 mine, and it comes out with a good report for the company (30 July, p 38). Surprise!

I trained to do environmental impact assessments at university but realised when graduating that, as they are almost invariably commissioned by developers, you won’t make a living if your reports are too critical.

Until reports are commissioned by the state, independently of corporate interests, there seems to be little point in them.

London, UK

Cry me a river with or without DNA From Doug Cross Having been a principal ecologist on a large study of the potential impacts of proposed hydropower projects in the Lower Mekong Basin, I can assure you that

@newscientist

newscientist

knowledge of what species exist where has no significant effect on which schemes will be implemented. So the notion that collecting a DNA database for rivers “may help limit the damage” to aquatic species caused by dams is naive (9 July, p 20).

The goal is power generation, not the preservation of fish stocks.

Despite analysis of the probable impacts on the highly productive fisheries downstream of the proposed sites, and warnings of dramatic losses should some sites be selected for power generation – even by so-called low-impact “run of river” schemes – decisions to build dams and generating stations are almost entirely governed by geopolitical goals.

Inconvenient environmental and social impacts are simply downgraded or ignored. In this competitive international development sector, science is utterly subservient to politics. To suppose otherwise merely confers a spurious veneer of reliability to environmental analyses that justify the unfettered application of technology.

Lowick Bridge, Cumbria, UK

Other species that dine on jellyfish From Guy Cox Tamar Stelling reports Andrew Sweetman’s search to discover what eats jellyfish, and eventual finding that fish do (16 July, p 26).

They also form a substantial part of the diet of juvenile green sea turtles (Chelonia mydas). Adults switch to a vegetarian diet of seagrasses and algae.

Unfortunately, Sweetman’s Norwegian fjords are far too cold to attract the turtles, however many jellyfish may be available.

St Albans, New South Wales, Australia From Roger Hill There are a few other animals that eat jellyfish: some jellyfish

“ Makes sense. I have MS, and rarely catch anything.

So before MS, I thought I was invincible.” agdalene Sivertsen offers one data point for autoimmune diseases M being side effects of a strong immune system (6 August, p 15).

predate other jellyfish, and leatherback turtles feed almost exclusively on them.

Jellyfish predators feed mainly at depth, but the culling techniques described in the article all work at the surface. Protecting leatherbacks, particularly their breeding beaches, would seem the best way to control jellyfish.

Manchester, UK

Computer says what, why?

From Richard Cragg Thank you for Regina Peldszus’s review of Samuel Arbesman’s book warning that we have reached the stage where very few “experts” really understand the complexity of the software systems they have installed to control critical parts of our infrastructure (23 July, p 42).

This reminds me of the lament of Nobel laureate Eugene Wigner: “It is nice to know that the computer understands the problem. But I would like to understand it too.”

London, UK Tom Gauld

Patently protect new uses of drugs

But the patent system is trying its utmost to find solutions.

Chichester, West Sussex, UK

From Alan Wells Your Leader article asserts that the patent system does not provide protection for the use of old drugs for new diseases (16 July, p 5). But, in the UK and Europe at least, drugs companies will be aware of the availability of “second medical use” claims in patents. They have been applying regularly to patent “substance X for use in treatment of Y”. The problem is enforcing the patent for use to treat a second disorder, when that for the first expires.

An example is the complex patent dispute over the use of pregabalin for pain relief, after the patents covering uses including epilepsy and generalised anxiety disorder expired.

The drug was then marketed with a “skinny label” referring only to those medical indications which do not infringe the seconduse patent.

This case may well to go to UK Supreme Court. This is a legal minefield, amid sweeping change.

The editor writes: n Even with a second-use patent these drugs may still not turn a profit, as doctors in the UK and other jurisdictions are able to prescribe drugs “off-label”. It is unclear whether they can be prevented from prescribing a lower-priced alternative.

The varieties of human force field From Duncan Butlin Anil Ananthaswamy discusses an “invisible force field” surrounding humans (9 July, p 10). I believe there is a more important “field”: the effect of our presence on those around us.

The “peripersonal space” described exerts no force, whereas presence can affect everyone within eyesight, and hundreds simultaneously in a crowd.

The force is transmitted mainly through posture, gesture and eye

contact. A threatening stare, for example, challenges everyone within range. Denial is useless: one can forget one’s own presence, but can never turn it off.

Chichester, West Sussex, UK

Testosterone overdose alert From Chris Wilkins Narcissistic behaviour may, Emma Young reports, be caused by overindulgent parenting (9 July, p 26). That, for me, was the most persuasive part of her article. However, there are other contributory and complementary traits that may play a role.

For example, the amount of testosterone we possess correlates with who gets to be the “alpha male”. We know that in a fight the amount of the hormone increases and one of the changes it brings is to reduce the ability to empathise.

It’s more difficult to hit someone when you feel their pain. So testosterone by default makes us more selfish and self-serving.

Tewin, Hertfordshire, UK

For the record n Zinc and brass are merely separated well enough on the galvanic series to generate voltages (25 June, p 47). n Logged off: the wood found offshore at Cleethorpes is better described as being preserved by immersion (23 July, p 12). n Tanja Masson-Zwaan is an assistant professor at the International Institute of Air and Space Law at Leiden University (9 July, p 32).

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FEEDBACK

For more feedback, visit newscientist.com/feedback

“If we didn’t remove incredibly powerful fire retardant asbestos & replace it with junk that doesn’t work, the World Trade Center would never have burned down.”

(17 October 2012) “The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing non-competitive.” (6 November 2012) “How amazing, the State Health Director who verified copies of Obama’s ‘birth certificate’ died in plane crash today. All others lived” (12 December 2013)

Paul McDevitt

“Snowing in Texas and Louisiana, record setting freezing temperatures throughout the country and beyond.

Global warming is an expensive hoax!” (29 January 2014)

MUCH has been made of the rise of post-truth politics – the idea that while politicians are still as dishonest as ever, they no longer even pretend to stick to the facts. An exemplar of this is US presidential candidate Donald Trump, a man who doesn’t lie so much as see the truth as a bad investment.

Lately Trump has been accused of softening the Republican stance on Russia.

Quizzed on Vladimir Putin’s military adventurism, Trump insisted that the Russian leader had no expansionist plans: “He’s not going into Ukraine, OK, just so you understand,” he told George Stephanopoulos at ABC News. “You can mark it down.”

Stephanopoulos was prompted to point out that Russian forces are already there, having annexed Crimea in 2014. “Well, he’s there in a certain way,” Trump admitted, before adding, inexplicably: “But I’m not there.”

TRUMP’S Heisenbergian take on Putin’s whereabouts encourages Feedback to cast an eye over the pompadoured presidential candidate’s

“Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn’t feel good and changes - AUTISM. Many such cases!”

forays into matters scientific and more. We feel these can only be adequately conveyed in the great orator’s own words, taken verbatim from his Twitter feed.

(28 March 2014)

“I predicted the 9/11 attack on America in my book “The America We Deserve” (29 December 2011)

(2 August 2014)

“Not only are wind farms disgusting looking, but even worse they are bad for people’s health” (23 April 2012) “An ‘extremely credible source’ has called my office and told me that @BarackObama’s birth certificate is a fraud.” (6 August 2012) “Remember, new “environment friendly” lightbulbs can cause cancer.

Be careful-- the idiots who came up with this stuff don’t care.”

(17 October 2012)

“ Roger Gladwell is tickled by a sign he spotted by the highway as he drove north from Southampton, UK: “CCTV cameras take your litter home”… Well, that’s a new use for them 56 | NewScientist | 13 August 2016

PREVIOUSLY, Jocelyn Penington wrote in to question Shakespeare’s astronomy credentials, evident in Hamlet’s love letter to Ophelia (30 July).

James Fradgley draws our attention to a further example in Julius Caesar, in which the titular character exclaims: “I am constant as the Northern Star”.

Unfortunately for the Bard, “in 55 BC there wasn’t anything nearby that one could call a northern star”, says James.

“In any case, Polaris is five stars, a Cepheid variable.” Perhaps the Roman leader was not as constant as he hoped?

PETNET sells $150 internet-linked feeding bowls for cats and dogs, allowing you to dispense food from afar using your smartphone.

But in a novel twist on Schrödinger’s pet-care practices,

“The U.S. cannot allow EBOLA infected people back. People that go to far away places to help out are great-but must suffer the consequences!”

“I am being proven right about massive vaccinations—the doctors lied. Save our children & their future.”

(3 September 2014) the company’s servers controlling the “Ebola is much easier to transmit than the CDC and government representatives are admitting.

Spreading all over Africa-and fast.

Stop flights” (2 October 2014) “We must suspend immigration from regions linked with terrorism until a proven vetting method is in place.”

(26 June 2016) Feedback can at least agree with one bombastic pronouncement from the ornery demagogue: “The global warming we should be worried about is the global warming caused by NUCLEAR WEAPONS in the hands of crazy or incompetent leaders!” Quite.

bowls unexpectedly went down, leading Petnet to warn customers: “You may experience a loss of scheduled feeds and failed remote feedings. Please ensure that your pets have been fed manually until we have resolved this issue.”

Feedback can’t help but ask: if manually filling your pet’s bowl was an option, why would anyone need a remote feeder in the first place?

You can send stories to Feedback by email at feedback@newscientist.com.

Please include your home address.

This week’s and past Feedbacks can be seen on our website.

Last words past and present at newscientist.com/lastword

THE LAST WORD Clean living Does it make sense to recycle messy small plastic items such as yogurt pots, given that householders use comparatively large amounts of warm water to rinse them?

item, and lays the burden on future generations.

People are rightly concerned about nuclear waste, and, of course, it has great potential hazards – but much domestic waste in the form of plastic also lasts a long time, especially where large quantities accumulate.

n It is a good idea to collect this material, especially as some of “Plastic in landfills might the polymers in them are quite last for millennia, leaking valuable once recycled. The and belching toxic advice that we at the Waste and materials” Resources Action Programme give consumers is to quickly rinse these items to remove any food In Florida, the most prominent residues – they do not need to landscape features I saw were be squeaky clean. You could landfills and, if not removed, they save them to do after you’ve might last for millennia, leaking done all the washing up and and belching toxic materials, and use the dishwater. wasting resources for the WRAP (the organisation behind foreseeable future.

Recycle Now, the national Unlike the concentrated recycling campaign for England) resources that a householder’s rinsed yogurt pots and drinks n As you point out, the cans represent, a lot of domestic immediate costs are hard waste is too diffuse for most to justify, and no sensible forms of economical recycling. householder will waste more Jon Richfield resources on such a task than Somerset West, South Africa the items are worth.

However, there is more to the equation than just how People-tasting much plastic, or indeed, glass What do humans taste of? I have or metal one can recycle. A heard that it’s a little bit like pork good deal of energy went into (not that I want to find out). But if it is, making the polymer or metal, why? And if it isn’t, what do we taste including its sheer fuel value in of? Also, why do different meats – say some cases, so the equation must lamb, beef, chicken or pork – taste allow for the often greater cost of different anyway? destroying dirty, unsegregated waste rather than recycling clean, n Apparently, in parts of sorted waste. the Pacific region where Disposal may be more human flesh was eaten, expensive than creating a new

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it was known as “long pig”.

Pigs and apes are both forest animals, and their way of dealing with predators is to run for cover.

Apes run for the nearest tree and climb it; pigs head for the nearest thicket and hide in it.

Both manoeuvres require some intense but short-lived muscular exertion.

Cattle and sheep are animals of the open country, and escape from predators by outrunning them. This requires endurance, so their muscles are rich in myoglobin to provide on-board oxygen supplies. The myoglobin makes their meat red and gives it quite a different flavour to that of forest animals.

Hazel Russman London, UK

This week’s questions

Those veggIE blues

Edible fruits and vegetables come in practically every shade of green, red and yellow. Why are so few of them convincingly blue in colour?

Duncan Hutchinson, Newton Abbot, Devon, UK Offal way to die

The Last Word has told us that lions prefer to eat the fat and organs of their prey rather than the muscle. Apparently, muscle tissue is relatively poor in energy and vitamins (for lions, at least), and lions are able to make glucose in the liver from protein, so do not need carbohydrates. What, then, are the equivalents in humans?

And if, when civilisation crashes, I finally manage to catch a stray cat or dog, which parts should I eat first, and why?

Quentin Macilray Limassol, Cyprus

High-flyers

Blood sausage

In the spring and summer, I see swallows swooping in the air, presumably to eat flying insects – so why are the insects way up there?

Milo Seal Seattle, Washington, US

A full mosquito must be much heavier than an empty one – and they can consume a lot of blood.

What is it about the mosquito that allows it to carry such a heavy load? And what is the percentage increase in body weight between a mosquito that hasn’t had a meal of blood and one that has? How does its prorata load-carrying ability compare with that of, say, a buzzard or vulture, which must also gorge when the opportunity presents itself?

Bill Reed Davie, Florida, US

Bolted on

Is the exact spot where a bolt of lightning will strike the earth pretty much predetermined at the moment it leaves a cloud? Or does it continuously change direction on the way down?

John Butcher Sunbury-on-Thames, Surrey, UK

Question Everything The latest book of science questions: unpredictable and entertaining. Expect the unexpected Available from booksellers and at newscientist.com/questioneverything