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LUCKY BREAK How neutrinos saved the early universe LABOUR PAINS Health warning about risks of natural childbirth MOON GRAB Luxembourg’s lunar gold rush WEEKLY July -15, 2016 GREEN AND BREXIT LAND Could leaving the EU help the environment? No3081 US$5.95 CAN$5.95 70989 30690 Science and technology news www.newscientist.com US jobs in science DESERT FIRE Exploring the lost volcanoes of the Sahara FOCUS LONGER ANDRZEJ WOJCICK/SPLI/GETTY Subscribe to New Scientist Visit newscientist.com/9016 or call 1-888-822-3242 and quote offer 9016 Live Smarter C9 Moonphase CONTENTS Volume 231 No 3081 This issue online newscientist.com/issue/3081 Leaders News News Labour pains UPFRONT Herpes turtle trouble on Barrier reef Juno reaches Jupiter Alien-hunting telescope Zambia’s vulnerable hippos culled First fatality in autonomous car THIS WEEK Neutrinos may explain missing antimatter Colourful sign language Feel the force of your personal space NASA’s biggest rocket 14 IN BRIEF Gut bacteria eat brain chemical Lazy bears stick to dumps CRISPR snips out herpes viruses Rafting sea slug goes global Hunt for invisible aliens SPUTNIK/SCIENCE PHOTO LIBRARY Health warning about risks of natural childbirth The risks of natural childbirth should be clear Don’t go ape over gibbon conservation On the cover 26 Lucky break How neutrinos saved the early universe Labour pains Risks of natural childbirth 32 Moon grab Luxembourg’s gold rush 19 Green and Brexit land How leaving the EU could help the environment 36 Desert fire Volcanoes of the Sahara Me! Why a little vanity can get you a long way Analysis 16 Teen health What are hormonal contraceptives doing to teenage girls? 18 COMMENT Let Mars rover check out “life" zone It’s vital that robots fire up our empathy 19 INSIGHT Brexit may not doom the environment Technology 20 Testing the DNA of rivers Machines don’t see the world like we A virtual journey inside a cell Giving plants a voice Cover image Lettering by M Deuchars Features Aperture 36 24 Inside the lightning strike lab Features Desert fire 26 Me! (see above left) 30 Plight of the Hainan gibbon The race to save the world’s rarest mammal 32 Moon grab Luxembourg’s lunar gold rush 36 PEOPLE Desert fire (see left) Exploring the volcanoes of the Sahara JAN KUPER Culture Coming next week… Does reality exist without you? Making the universe one random act at a time Jellymageddon How to stop jellyfish taking over the world 42 Listening to everyone Do antidepressants work? It depends who you ask 43 Eat the enemy Tasty invasive species 44 Old world The challenge of being 100 Regulars 52 LETTERS Out with obscure dark energy 56 FEEDBACK Homeopaths Without Borders 57 THE LAST WORD Earth’s angle explained July 2016 | NewScientist | AF ARCHIVE/ALAMY STOCK PHOTO LEADERS LOCATIONS USA 50 Hampshire St, Floor 5, Cambridge, MA 02139 Please direct telephone enquiries to our UK office +44 (0) 20 7611 1200 UK 110 High Holborn, London, WC1V 6EU Tel +44 (0) 20 7611 1200 Fax +44 (0) 20 7611 1250 Australia Tower 2, 475 Victoria Avenue, Chatswood, NSW 2067 Tel +61 9422 8559 Fax +61 9422 8552 SUBSCRIPTION SERVICE For our latest subscription offers, visit newscientist.com/subscribe Customer and subscription services are also available by: Telephone 1-888-822-3242 Email subscribe@newscientist.com Web newscientist.com/subscribe Mail New Scientist, PO Box 3806, Chesterfield, MO 63006-9953 USA One year subscription (51 issues) $154 CONTACTS Contact us newscientist.com/contact Who’s who newscientist.com/people General & media enquiries enquiries@newscientist.com Editorial Tel 781 734 8770 news@newscientist.com features@newscientist.com opinion@newscientist.com Picture desk Tel +44 (0) 20 7611 1268 Display advertising Tel 781 734 8770 displaysales@newscientist.com Recruitment advertising Tel 781 734 8770 nssales@newscientist.com Newsstand Tel 212 237 7987 Distributed by Time/Warner Retail Sales and Marketing, 260 Cherry Hill Road, Parsippany, NJ 07054 Syndication Tribune Content Agency Tel 800 637 4082 New Scientist Live Tel +44 (0) 20 7611 1273 live@newscientist.com © 2016 Reed Business Information Ltd, England New Scientist ISSN 0262 4079 is published weekly except for the last week in December by Reed Business Information Ltd, England New Scientist (Online) ISSN 2059 5387 New Scientist at Reed Business Information 360 Park Avenue South, 12th floor, New York, NY 10010 Periodicals postage paid at New York, NY and other mailing offices Postmaster: Send address changes to New Scientist, PO Box 3806, Chesterfield, MO 63006-9953, USA Registered at the Post Office as a newspaper and printed in USA by Fry Communications Inc, Mechanicsburg, PA 17055 A woman’s right to choose The risks of all forms of childbirth should be made clear THE 1983 movie Monty Python’s The Meaning of Life opens with a scene in a hospital room where a woman is giving birth “More apparatus please nurse,” shouts one doctor “Get the machine that goes ‘ping’,” bellows another The mother-to-be and her baby are an afterthought The scene was (in part) a satire on the overmedicalisation of childbirth How times have changed A similar satire today would probably target the excessive promotion of natural childbirth as the ideal In the UK, for example, women who request a caesarean section for non-medical reasons – which the National Institute for Health and Care Excellence says they should be allowed as long as they are warned about the risks – are often blocked from having one, or have to jump through so many hoops they give up Vaginal birth is, of course, the natural endpoint of a pregnancy, but natural does not necessarily mean good And while it is right to inform women about the risks of non-medical C-sections, the playing field is not a level one Pregnant women who choose a vaginal delivery are not officially warned about the possibility of bad outcomes for themselves or their babies Now UK doctors are considering whether to formally warn women about the risks of giving birth vaginally (see page 8) The medical evidence is on their Go ape? Not just yet WHAT is the world’s rarest mammal? If you have no idea, you’re not alone The Hainan gibbon – current head count 26 – may be on the brink, but there is barely a murmur of publicity about efforts to conserve it Maybe that is no surprise We often hear about extremely rare species only once it is too late The plight of the baiji, for example, only came to the world’s attention after the last sighting in 2002 Five years later it was extinct Given this precedent, what odds we have of saving the gibbon? Is it even worth trying? Those are key questions in conservation biology right now (see page 30) Some argue that we should only invest in relatively healthy populations or ecosystems rather than fight rearguard actions to save species on the edge side Planned C-sections are the safest option for the baby, because they avoid any chance of brain damage from a vaginal birth and the not-insignificant risk of stillbirth after 39 weeks A planned C-section is also the only guaranteed way to avoid a risky emergency C-section And they are cheaper in the long run once the costs of caring for injured mothers and children are taken into account Obstetricians’ leaders are still deciding whether to press ahead, perhaps fearing a battle with natural birth campaigners But if they delay much longer they will be letting down the patients they are meant to serve Sometimes medicalisation is best ■ That is a valid point However, the Hainan gibbon increasingly represents the future of conservation Vertebrate populations have declined by about half since 1970, and more and more species are dwindling towards extinction Working out what can be done for those that have been reduced to Hainan gibbon levels will only become a more common problem Efforts to save it are clearly worthwhile, if only to learn lessons that will maximise future success ■ July 2016 | NewScientist | RINGO H.W CHIU/AP/PA UPFRONT Juno at Jupiter, at last JUBILATION, relief and exhaustion That was the reaction at NASA’s Jet Propulsion Laboratory in Pasadena, California, the heart of the Juno mission, when the probe pulled into orbit around Jupiter on Monday night It was the most dangerous day for NASA’s Juno spacecraft since its launch in 2011 Long communication times between Earth and the probe made human help impossible, so mission engineers could nothing but wait to hear whether it had succeeded Juno’s approach was the fastest ever by a spacecraft going into orbit, at more than 200,000 kilometres per hour relative to Earth In the event, the spacecraft slipped into a near-perfect orbit after a journey covering 869 million kilometres “We conquered Jupiter!” said mission lead Scott Bolton, who was overwhelmed as confirmation came in “All that went through my head is, ‘Wow It’s perfect.’” Bolton wasn’t exaggerating: Juno’s orbit is so close to ideal that it is a mere second behind its scheduled trajectory Juno is now in a 53.5-day capture orbit Then, on 14 October, it will burn its main engine, tightening up into a 14-day orbit This is also when it will turn its scientific instruments on to carry out its major observations Over the next year and a half, the craft will investigate some of Jupiter’s biggest mysteries, mapping the planet’s gravity and magnetic fields, looking for evidence of a solid core and tracking its auroras –By Jove, we did it– No need for drugs OUT with antibiotics for colds? People not experience more serious health problems when family doctors are stricter about prescribing the drugs for conditions such as coughs, colds and sore throats – a finding that should help stop the spread of antibiotic resistance Martin Gulliford at King’s College London and his team studied 610 general practices in the UK and found that, overall, those that prescribe fewer antibiotics for respiratory “This study provides GPs with the evidence to convince patients they don’t need antibiotics” infections not have higher rates of serious bacterial complications, such as meningitis (BMJ, doi.org/bkrd) However, the researchers did detect slightly higher rates of pneumonia and quinsy, a rare complication of sore throats They estimate that if an average-sized GP surgery with 7000 patients cut | NewScientist | July 2016 antibiotic prescriptions by 10 per cent, it would see one extra case of pneumonia a year and one more case of quinsy every decade “Both these complications can be readily treated once identified,” says Gulliford These findings are encouraging for family doctors, who have to decide many times a day whether to prescribe antibiotics, without knowing if a person’s condition is caused by bacteria or a virus Using antibiotics for what is actually a viral infection helps spread drug resistance, but the fear has been that failing to catch a bacterial infection in its early stages can have severe consequences “This is an important study and addresses a very emotive subject,” says Adam Roberts, who studies antibiotic resistance at University College London “The pressure on GPs to reduce prescriptions is increasing, and this study provides them with the evidence they need to convince patients that, at least for respiratory tract infections, it is not going to harm them if they don’t receive the drugs.” Deeper exploration THE deep sea is about to yield more of its secrets The Nekton alliance, launched this week, brings together more than 30 international organisations from the fields of science, technology and business to try to learn more about Earth’s final frontier “We know more about the surface of Mars and the moon than we about our own seabed,” says principal scientist Alex Rogers at the University of Oxford The alliance’s XL Catlin Deep Ocean Survey will kick off with dives in Bermuda this month, using both manned and autonomous submersibles Rogers says such increasingly sophisticated craft are giving us unprecedented access to the deep sea “We see a great need to learn, and we now have the technology to it.” Nekton’s ultimate aim is to diagnose the health of waters below 200 metres, to better inform policy decisions on protecting these habitats Tesla: accidents will get rarer THE first death in an autonomous car has occurred According to the US road safety administration, Joshua Brown was killed in Florida in May after his Tesla Model S hit a truck while in autopilot mode Brown was on a highway when the truck joined the road from a cross street Unable to pick out the white truck against the bright sky, the self-driving system failed to brake Florida police found a DVD player in the car, but it is not known if Brown was watching a movie at the time Tesla said the accident was a tragic loss “As more real-world miles accumulate and the software logic accounts for rare events, the probability of injury will keep decreasing,” it said in a statement The fatality will raise tough questions about the safety of semi-autonomous cars but should not be seen as an indictment, says Hussein Dia of Swinburne University of Technology in Australia For new stories every day, visit newscientist.com/news Anyone out there? CHINA finished building the largest radio telescope in the world this week – and will use the enormous dish to listen for aliens The Five-hundred-meter Aperture Spherical Telescope WILL BURRARD-LUCAS/NATUREPL.COM/ALAMY 60 SECONDS Onwards and outwards After its fly-by of Pluto last July, the New Horizons spacecraft has got one final job before its fuel runs out NASA has approved an extension of the mission to visit 2014 MU69, an ancient object just 30 kilometres across The probe will head out into the Kuiper belt and is scheduled to reach MU69 on January 2019 “Individual panels can be rearranged to track specific objects, giving it greater range and sensitivity” Don’t take it lying down JASPER JUINEN/BLOOMBERG VIA GETTY IMAGES (FAST) is the size of 30 football pitches, dwarfing its nearest rival, the 300-metre-wide Arecibo Observatory in Puerto Rico Assembled from 4450 triangular panels, the dish should Hippo cull go-ahead be able to detect astronomical AS MANY as 2000 hippos may be objects whose radio signals are killed over five years in Zambia too weak to be picked up by The government has resurrected smaller telescopes And aliens a culling plan it suspended in Construction of FAST began mid-June Animal welfare groups in 2011 It is situated in Guizhou province in a natural bowl-shaped say there is no solid scientific case for the cull, which may be carried feature that is ideal for housing out by paying trophy hunters the colossal concave disc The government has put The individual panels can be forward various reasons for rearranged to focus on and track the cull in the South Luangwa radio waves from specific objects National Park These include of interest, which will give the preventing anthrax, which dish much greater range and sensitivity than rival dishes “There’s relentless effort “The size of this telescope is to press ahead with the key to its scientific impact,” says suspended cull, even Tim O’Brien at the University of without scientific backing” Manchester, UK “The bigger the telescope, the more radio waves hippos can spread, claims of it collects and the fainter the overpopulation and of water objects it will be able to see.” levels too low to support both hippos and the other wildlife Yet there’s no current anthrax outbreak and water levels are the highest they have been in five years, says Will Travers, president of wildlife charity the Born Free Foundation “They are on thin ground scientifically.” The government suspended the cull on 14 June, following protests by animal rights activists But senior officials met on 22 June in Lusaka to recommend the cull go ahead after all, the Born Free Foundation claims “There’s a –Attention still needed– relentless effort to press ahead,” –Run for your life– says Travers “But at the moment, I can’t see how they can justify what’s going on.” He has now written to Zambian president Edgar Lungu asking for the cull to be abandoned, and for open publication of the rationale for killing the animals Officials hadn’t replied to New Scientist’s request for comment as we went to press Turtles in trouble IT’S a turtle tragedy Tumours are crippling an increasing number of green sea turtles on Australia’s Great Barrier Reef The affected animals have a turtle-specific herpes virus that causes fibropapillomatosis – a condition in which disfiguring tumours grow on and inside the body Those can block vision and increase risk of other infections, says Karina Jones at James Cook University in Townsville, Australia Her team’s surveys this year shows that in parts of the reef as many as half of the turtles have these crippling tumours “We think there must be some external trigger that causes the tumour development,” says Jones Turtles in healthy marine environments can still carry the virus, but it often lies dormant with no symptoms The next step is to try to pin down the pollutants responsible The idea that women are more likely to conceive if they lie down to help sperm reach the egg is bogus Women who rested for 15 minutes after insemination were no more likely to get pregnant than those who moved around The work was presented at the annual meeting of the European Society of Human Reproduction and Endocrinology in Helsinki, Finland Cosmic weather map In March, a software glitch caused the Japanese X-ray space telescope Hitomi to spin itself to pieces just six weeks after launch But before the malfunction, the probe mapped one of the largest weather systems in the universe, the flowing plasma of a clump of galaxies known as the Perseus cluster (Nature, DOI: 10.1038/nature18627) Greenpeace under fire A third of all living Nobel laureates have signed a letter criticising Greenpeace’s stance on genetically modified crops Greenpeace has “misrepresented the risks, benefits and impacts” of GM crops, they say, adding that “there has never been a single confirmed case of a negative health outcome for humans or animals from their consumption” Asleep, one ear open King penguins sleeping on a beach react to different levels of threat, the Society for Experimental Biology meeting in Brighton, UK, has heard When orca or skua calls were played, the penguins woke up and fled Sounds of non-predators woke them but they did not flee July 2016 | NewScientist | THIS WEEK Doctors may warn of birth risks Official advice on the risks of vaginal birth could soon be given to women first childbirth, he found that the emergency C-section, which risk of injury to a woman’s pelvic carries a higher risk of infection, floor muscles from vaginal birth haemorrhage and blood clots rises by per cent The risk of one than planned C-sections of these muscles detaching from Dietz argues that women the pubic bone – which greatly should be warned about how raises the risk of uterus prolapse – factors like age and having a big was 10 per cent for a 20-year-old baby make vaginal birth more having a vaginal delivery without difficult In April, he suggested the use of instruments like that, given that patients are forceps, but this doubled to warned of risks as low as in 1000 20 per cent for a 40-year-old before surgery, it is incongruous Age is a factor because our not to warn a woman having her muscles and ligaments get less “You should be able to stretchy as we grow older This weigh up the risks, but makes them more likely to tear you can’t if you don’t during childbirth, and increases have the information” the likelihood of needing an Clare Wilson FOR the first time, pregnant women in the UK may be given official advice about the relative risks of vaginal births and caesarean sections The move comes in the wake of a landmark 2015 UK Supreme Court case that awarded damages for a baby who sustained brain damage during vaginal birth In this case, the plaintiff had a higher than usual risk of having a difficult birth, due to having a small pelvis and diabetes But doctors didn’t inform her of these increased risks – an act of “medical paternalism”, said the presiding judge, who decided in the mother’s favour This ruling is seen as applying to all births Although advice is available for those who seek it out, women are not officially warned about common risks such as tearing and incontinence, because vaginal birth is seen as the default outcome of pregnancy first child at 38 that she has a 15 per cent chance of an anal tear (American Journal of Obstetrics and Gynecology, doi.org/bkpw) “They have the right to know that,” he said At the moment, women considering C-sections are warned about potential risks, like wound infections, blood loss and riskier future pregnancies But women aren’t warned about the risk of bad tearing during vaginal birth, which can lead to problems in later life “They have got leaflets about C-sections, yet most people opt for a vaginal birth and there are In many countries, including the UK, the average age of mothers at birth has been rising for decades For example, in 1973, the average age at childbirth in England and Wales was 26 years, but by 2014 this had risen to 30 Research is now revealing how age raises the risks from vaginal delivery A recent study by Hans Peter Dietz of Sydney Medical School, Australia, found that women who have their first child later in life are more likely to have major pelvic floor injuries during vaginal birth – damage that can lead to incontinence (American Journal of Obstetrics and Gynecology, doi.org/bkps) For every extra year at age of | NewScientist | July 2016 SPUTNIK/SCIENCE PHOTO LIBRARY Age matters –Consent form needed?– For more books and arts coverage, visit newscientist.com/culture A hundred and counting A centenarian society is on its way It’s going to be a huge challenge, finds Marek Kohn The 100-Year Life: Living and working in an age of longevity by Lynda Gratton and Andrew Scott, Bloomsbury, £18.99 AFP/GETTY IMAGES WHEN Poles want to wish somebody well, they wish them a hundred years of life This is a charming prospect, as long as the chances of it coming to pass are vanishingly small But once it starts to look as though it might actually happen, you may think that people should be careful what they wish for you As Lynda Gratton and Andrew Scott make arrestingly clear, it will take a lot more than good wishes to make sure that a hundred years is a blessing, not a curse Life expectancies have been rising by up to three months a year since 1840, and there is no sign of that flattening Gratton and Scott draw on a 2009 study to Gratton and Scott advance the show that if the trend continues, idea of a multistage life, with more than half the babies born in repeated changes of direction and wealthier countries since 2000 attention Material and intangible may reach their 100th birthdays assets will need upkeep, renewal With a few simple, devastating or replacement Skills will need strokes, Gratton and Scott show updating, augmenting or that under the current system it is discarding, as will networks almost certain you won’t be able of friends and acquaintances to save enough to fund several Earning will be interspersed with decades of decent retirement For learning or self-reflection As the example, if your life expectancy authors warn, recreation will have is 100, you want a pension that is to become “re-creation” 50 per cent of your final salary, Clearly this will be expensive and you save 10 per cent of your As well as saving for retirement, earnings each year, they calculate people will need to pay for selfthat you won’t be able to retire till reflection phases and education your 80s People with 100-year If you are, say, a hairdresser, you life expectancies must recognise they are in for the long haul, and “More than half the babies born in wealthier countries make an early start arranging since 2000 may reach their lives accordingly their 100th birthdays” But how to go about this? 44 | NewScientist | July 2016 Our young selves should hang on to rewards for our older incarnations won’t need to worry too much about skills becoming obsolete But you probably won’t be able to afford much self-renewal Gratton and Scott point out the twofold inequality of lengthening lifespans: the rich live longer than the poor, and the better-off are better off in all the resources needed to make increasing longevity a blessing not a burden Even the better-off will mostly be stretched by the demands of the multistage life, though, and so the need for a good partner will loom ever larger Although two can’t live as cheaply as one, they can live more cheaply together than apart Crucially, too, partners will look to each other for financial cover when not earning There’s a contradiction here that the authors don’t really acknowledge The 100-year life demands constant review and readiness to change one’s work and one’s self, but relies heavily on commitment to one’s partner Yet people already review their relationships, resulting in changes of partner They may need to reverse that policy Perhaps Gratton and Scott felt their groundbreaking book should skirt some of the tougher terrain, so as not to discourage readers who aren’t ready to think as boldly as they The most significant absence is about ageing itself Although they note that financial literacy declines with age, for the most part they write as though people think and feel much the same way whatever age they are Yet recent research illustrates that younger and older people have different incentives Researchers at University College London, for example, found that older people don’t respond as strongly to rewards as younger ones They think that may be because the “reward” neurotransmitter, dopamine, declines by up to 10 per cent every decade If they are still working, older people will be competing with younger people who have more motivation in their synapses Hopefully those younger people will have the foresight to hang on to their rewards so they can pass them on to their less motivated, less competent older selves The 100-year life will need the old to be young, and the young old ■ Marek Kohn is a science writer based in Brighton, UK Take a Chance Explore the science and secrets of luck, randomness and probability in the latest book from New Scientist, available now from all good bookstores newscientist.com/chance letters@newscientist.com LETTERS EDITOR’S PICK Out with obscure dark energy From Rosemary Campbell As a humble, long retired physics teacher, I am delighted to read of qualified opposition to the notion of dark energy (18 June, p 28) Dark matter is indigestible enough, but it at least has the merit of a potentially discoverable particle to explain its existence Dark energy, depending as it does on the overall uniformity of the universe, seems like a step too far in light of discoveries of enormous overdense chunks of galaxies interspersed by under-dense voids And may I congratulate the artist responsible for the picture that so brilliantly foreshadows the possible dissolution of dark energy in the development of ideas of curved space? Glen Waverley, Victoria, Australia From Conrad Norris As a non-physicist, even I could understand this article about the possible banishment of dark energy I would suggest, though, a better analogy for the “heretics” undermining the “dark side” than comparing them to Copernicus How about the collapse of the hypothesis that a Planet Vulcan between Mercury and the sun could explain the planet’s non-Newtonian orbit? While Copernicus debunked religious dogma with observation and science, Einstein’s theory of general relativity explained the orbit and turned good Newtonian science into great science Lower Earley, Berkshire, UK 52 | NewScientist | July 2016 Anticipating crimes of the future From Paul Ekblom, Department of Security and Crime Science, University College London Your cartoon of the truncheonholding bobby peering into the crystal ball presents a funny side of crime anticipation (Feedback, June) But the purpose behind the Dawes Centre for Future Crimes at University College London is to address the crime and security implications of rapidly emerging technologies and social changes, and to develop pre-emptive measures to address them Its research will span social, physical, computer and engineering sciences, driven by commitment to real-world impact and scientific rigour Society has an unfortunate history of new technologies being followed by “crime harvests” – think of mobile phones, the internet, 3D printers and drones Getting ahead of criminals is a much-needed strategic extension to the arm of the law Tunbridge Wells, Kent, UK Cannibalism may not be the answer From Nuala McDonnell Archaeologists should consider alternative explanations to their standard interpretation that “cut marks and polishing on bones are hallmarks of cannibalism” (14 May, p 36) As recently as the last century, washing ancestors’ bones was normal practice in Okinawa, Japan, so that many generations of remains could be brought together in one tomb The dead were interred with appropriate ceremony One to three years later, to make space for another corpse, remains of flesh were removed from the bones using chopsticks, or, if decomposition wasn’t complete, a sickle When picked clean of all flesh, the bones were washed in water and saki and then placed in an urn Prayers of apology were offered to the deceased for having disturbed their bones Totnes, Devon, UK A universal metasimulation game From Ed Subitzky Geraint Lewis comments on Elon Musk’s suggestion that our universe is actually a simulation taking place inside a computer (11 June, p 18) He points out that the laws of physics operating in our universe would be whatever laws the coders decided to bake into their simulation However, the computer that runs the simulation must also exist in a universe – a “metauniverse” with its own physical laws, to which its objects and inhabitants are bound These meta-laws determine the laws the coders can “choose” for us Of course, the meta-universe could itself be a simulation embedded in a meta-meta-universe The laws of physics there would trickle down to determine the laws in the two universes beneath What if the sequence of metauniverses and simulations continues for a vast number of iterations? Would the laws get more real as we approach the top? If the sequence were infinite, there would be no privileged level at which the laws could be considered more real than at any other level In this case, the laws we experience around us would be as good as any, and we might as well just get on with them Since our attempts to create simulated universes are still extremely primitive, we would be at, or close to, the bottom of any chain that may exist New York, US From Dhiren Rao The theory that our universe may be a simulation was discussed by @newscientist newscientist Nick Bostrom and reported in New Scientist (27 July 2002, p 48) Berkeley, California, US Not the largest wooden structure From Martin Gregorie Feedback mentions a replica ark at the Creation Museum in Kentucky, which claims it is the “largest timber frame structure in the world”(4 June) Hangar at US Marine Corps Air Station Tustin, in California, has four times the area and eight times the volume, being 327 metres long, 89 m wide and 52 m tall It is all wood apart from the concrete frames for the sliding wooden doors at each end – these frames don’t support the main structure It was built in 1942 to shelter blimps Harlow, Essex, UK I’ve seen things you wouldn’t believe From Belinda Martin You mention that an artificial intelligence has “reinterpreted” parts of the 1982 film Blade Runner (11 June, p 24) Was this the original cinema release with the Harrison Ford voice-over – a thoughtful and thoughtprovoking discourse on what it means to be human and therefore of some interest to an artificial intelligence? Or was it one of the multitude of “director’s cuts” that reduce it to a mindless dystopian shoot-em-up? We wouldn’t want to give the AI any wrong ideas Newton Aycliffe, County Durham, UK The trouble with tiny demons From Paul G Ellis Stephen Battersby uses Maxwell’s demon to discuss the physical nature of information (14 May, “Outreach is at the heart of science Without effective outreach, what we has no real meaning” David Brockley, amid outrage, calmly appreciates our view that experts need to reassert their value to society (2 July, p 5) p 28) But how can the demon “see the motions of air molecules” or operate “a frictionless door” or “slide a partition” without some physical interaction? Surely, any useful modern analysis has to include the demon’s use of photons or the like (which are subject to Heisenberg’s Uncertainty Principle) to measure molecules’ momentum vectors in order to determine whether they should pass into a hotter location Similarly, some account is needed of the physical interaction involved in operating the door or inserting a partition Battersby mentions Leo Szilard’s approach to the thought experiment Though Szilard estimates the molecule’s work of pushing a partition, he appears to me to ignore the physics both of the initial insertion of the partition and of the demon measuring which end the molecule is in Chichester, West Sussex, UK From Guy Cox The description of Leo Szilard’s 1929 thought experiment really doesn’t work If we have a box TOM GAULD with only one molecule in it, and we introduce a movable partition, the molecule has to be on one side or the other A demon might know which side, but in its absence the partition would still move, though we couldn’t predict which way Exactly the same amount of work would be done and the molecule would lose just as much energy, thereby getting cooler This is classical thermodynamics, since with a molecule on one side and a vacuum on the other we have a pressure difference – or we have used the random position of the molecule to create one where there was none before Sydney, New South Wales, Australia The editor writes: ■ To extract work from the molecule, you need to apply some resistance for it to work against, and to that you need to know which way it will be pushing, and therefore which side of the partition it starts You could provide bi-directional resistance by making the partition slide against friction, but that’s no good, as with friction the motion just gets dissipated as heat Instead, you need to provide resistance that does something useful, such as winding up a weight against gravity The significance of the polygenic score From Eric Kvaalen You report that New Zealanders whose genetic profiles have higher “polygenic scores” have more prestigious occupations, higher incomes and more assets, and being more likeable and friendly (11 June, p 10) But the coefficients of correlation for these traits ranged from 0.10 to 0.13, except that for exams at age 15, which was 0.24 The squares of these numbers tells what fraction of the variance is “explained” by the factor So between per cent and per cent of the variation is due to these genes, except for the exam results, where it was per cent So let’s not get the wrong idea about the significance of these genetic contributions Les Essarts-le-Roi, France The editor writes: ■ The correlations may be small, but they are there, and a tiny percentage across a huge population could potentially have a big impact It is fascinating that there is a genetic influence on “success” at all Pinhead focus presumption flaw From Tim Stevenson I fear there is a flaw in Brian Pollard’s critique of my comment about the inability of a pinhead to cover the sun, as viewed by a wide open pupil at the Oort Cloud (Letters, 11 June) He assumes that the eye’s lens can simultaneously focus the distant sun and near pinhead on the retina My point is that the wide aperture in that dim light would make this impossible Prestwood, Buckinghamshire, UK Make a human genome at home From Theresa Cheapman You report concern over a meeting to discuss plans to synthesise a complete human genome, from which journalists were excluded (21 May, p 6) My partner and I have made two novel genomes We, like the scientists in your article, did not invite any journalists South Riana, Tasmania, Australia Letters should be sent to: Letters to the Editor, New Scientist, 110 High Holborn, London WC1V 6EU Email: letters@newscientist.com Include your full postal address and telephone number, and a reference (issue, page number, title) to articles We reserve the right to edit letters Reed Business Information reserves the right to use any submissions sent to the letters column of New Scientist magazine, in any other format July 2016 | NewScientist | 53 A LIBRARY OF KNOWLEDGE POCKET SIZED FREE! SUES SAMPLE IS ! P IN-AP Visit newscientist.com/app or call 1-888-822-3242 and quote offer 9056 Live Smarter For more feedback, visit newscientist.com/feedback FEEDBACK refrigerators today,” writes Ian Napier “Personally, however, I suspect they didn’t know what else to with it until the invention of sliced bread.” WE ARE left baffled, as David Moss is, by Glaceau brand bottled water, which boasts that it is “distilled spring water with added electrolytes” Isn’t that a rather circular process? How they tell the difference between the two? And when is the water deemed ready for drinking? PAUL MCDEVITT MEANWHILE, Crispian Strachan writes, there is also nominative anti-determinism at work in this universe “Some years ago, one English police force had a brass band led by a local conductor, one Major Crook,” he says And perhaps in a similar vein, there is South Yorkshire comedy duo the Chuckle Brothers WITH the Olympic Games in Rio just a month away, plenty of companies are hoping to cash in Rebecca Robbins of medical publication STAT gives a tour of some of the goods claiming to protect against Zika virus, including stickers, hats, nets, wristbands and bracelets All are infused with anti-mosquito spray, and all offer protection that is dubious at best Add to this “anti-Zika condoms” to prevent sexual transmission of the virus (all condoms offer such protection), and herbalists offering turmeric, basil and ginger as a way to waste good curry ingredients in ineffective antivirals And of course, we are told by Homeopaths Without Borders that the water cure offers prophylaxis against such epidemics – dilutions of belladonna, poison ivy and boneset are said to be equally effective, which is to say, not at all Avoidance remains the best strategy, and while DEET is still the deterrent of choice, Feedback recalls, as Robbins does, the news last year that Victoria’s Secret Bombshell perfume offers some protection from Zika (28 November, 2015) – whether borne by mosquitoes or men FEEDBACK has been led up the garden path, writes Mark Fawcett (18 June) “Alicia Keys was not born with that name, but adopted it,” he says, because she felt it represented her identity as a performer This is therefore a case of harnessing the power of nominative determinism for career success, much like South Yorkshire comedy duo the Chuckle Brothers PREVIOUSLY The Irish Times hinted enigmatically that it was “not unusual” to discover lumps of millennia-old butter hidden in bogs (25 June) “The prevailing theory is that, being at an evenly cold temperature, bogs were used in ancient times much as we use Colin McCulloch writes: “Your comment on the ‘first cut’ article sponsored by Gillette reminded me of free condoms and chlamydia tests promoted in pharmacies under a Virgin Care logo” 56 | NewScientist | July 2016 DURING recent floods in Launceton, Tasmania, officials warned that “24,000 Volkswagens worth of water” was flowing through swollen rivers every second, reports Jon Burne “I immediately wondered which model the controller was referring to,” says Jon Feedback feels that Jon ought to focus on the spirit, rather than the letter of the warning MARK RIBBANDS is delighted by the acoustic specifications touted for the ventilation fan he’s fitting to a motorhome Not only is the device reported to be “silent at high speed” but, even better, it’s “exceptionally silent” at minimum speed IAN NAPIER, a name we’re sure sounds familiar, asks: “What is the term for having had that déjà vu feeling before? Is that just plain old déjà vu, déjà vu squared or something else entirely?” Perhaps one of Feedback’s wise readers can advise FEEDBACK has previously struggled with how to adhere to the rules of the Celebrity Diet – that is, selecting foods that are high in energy but low in calories – and came to the conclusion that food eaten on a mountain such as Helvellyn might fit the bill (4 June) “My teenage son, Luke, points out that the Celebrity Diet would be very successful” if this were the case, says Sean Kelly “Having dined on top of Helvellyn, you must descend to ground level to harness the potential energy stored within your low calorie dinner To eat again, you need to ascend Helvellyn again.” Weight loss will be rapid, we are assured MORE pre-science prescience in literary fiction: Dave Cheesman writes that Elon Musk’s Hyperloop is presaged in the July 1950 issue of The Eagle comic, “in which Dan Dare and his stalwart batman Digby are taken by the Treens to the capital of Venus in an ‘Electrosender’” This baroque transportation carriage is shot down a vacuum tube using electromagnets, reaching speeds of 24,000 kilometres per hour Sounds familiar, but no word yet from Musk on plans for Venus WHAT makes something healthy? A pack of Sunfood “raw organic apricot kernels” warns buyers they must limit themselves to just seeds per day, due to the presence of amygdalin, “which can cause symptoms of cyanide poisoning when eaten in excess” Nonetheless, we are also informed that the kernels come from wild trees untouched by any “pesticide, herbicide or synthetic fertilizer” What a relief! 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 A fresh angle If the world’s tilt was at a different angle, how different, if at all, would the world’s environment be? ■ The world’s tilt can be considered from two perspectives One is obliquity, or the angle between the plane of Earth’s orbit around the sun and the plane of Earth’s equator This tilt is essential for giving us the seasons, and does in fact vary with time It is currently at 23.4°, but shifts over a 41,000-year cycle between 22.1° and 24.5° So we can observe how changes in obliquity have affected Earth’s environment, particularly during the early Pleistocene epoch starting 2.6 million years ago Obliquity is one of the factors that Milutin Milankovitch hypothesised in the 1920s could drive glacial-interglacial cycles in the northern hemisphere Reducing the angle of obliquity, for example, decreases the mean annual amount of sunlight reaching the poles, making it more likely that winter ice will survive the summer without melting fully This means the following winter’s ice has a “head start” and will reach a greater extent than the previous winter As other feedbacks also begin kicking in – such as the fact that sea ice reflects more sunlight into space than seawater – the northern hemisphere descends into a cold glacial period with ice sheets up to kilometres thick across northern Eurasia and North America, and a global sea level around 100 metres lower than today Conversely, The writers of answers that are published in the magazine will receive a cheque for £25 (or US$ equivalent) Answers should be concise We reserve the right to edit items for clarity and style Please include a daytime telephone number and an email address if you have one New Scientist retains total editorial control over the published content Reed Business Information Ltd reserves all rights to reuse all question and answer increasing obliquity increases the ■ The axis around which Earth amount of sunlight reaching the spins is tilted at about 23.4° If poles, making it more likely for ice this changed, everything would to melt there during the summer be affected – temperature, It may be a small comfort that precipitation and life forms The obliquity is currently declining, easiest way to think about this is potentially counteracting a little to imagine the two extremes: of the human-induced global zero tilt and 90° If our planet’s warming for our descendants axis had zero tilt, we would Secondly, we can consider experience no seasons – no precession, or the “wobble” in the winter or summer, no change in orientation of Earth’s spin axis “The Earth’s tilt of 23.4° is (just like a spinning gyroscope) essential for giving us the over a period of 24,000 years seasons and does in fact Crucially, precession dictates vary over time” whether the summer solstice in the northern hemisphere occurs close to aphelion (the point where temperature throughout the year Earth is furthest away from the sun Seasons exist because the in its orbit) or perihelion (the point amount of solar energy received where it is nearest) by northern temperate and polar At present, our summers are at regions is highest when the North aphelion and thus relatively cool, Pole is most tilted towards the with our winters relatively mild sun (at the summer solstice on This is the ideal configuration 21 June) and least at the winter for a glacial period, because solstice (21 December) summer temperatures are not Now imagine Earth stops high enough to substantially melt rotating and our axis tilts to 90°, last winter’s ice (ignoring the with the South Pole pointing permanently at the sun That “At present summers are pole would have 24-hour sunshine cool, winters are mild This 365 days a year The Antarctic ice is the ideal configuration cap would melt, as the continent for a glacial period” became the hottest place on Earth The southern hemisphere human-induced greenhouse would be in constant light At the effect) An interglacial period equator, the sun would be in a would be expected to occur when perpetual sunrise/sunset position, precession leads to summer and the temperature would be perihelion and scorching heat at decidedly chilly that time of year, melting more The North Pole would see no ice – not something we would sunlight – and neither would the particularly welcome in our northern temperate zone Both current predicament would become extremely cold Sam Buckton They might receive a little warmth Cambridge, UK via winds and ocean currents, if material that has been submitted by readers in any medium or in any format and at any time in the future Send questions and answers to The Last Word, New Scientist, 110 High Holborn, London WC1V 6EU, UK, by email to lastword@newscientist.com or visit www newscientist.com/topic/lastword (please include a postal address in order to receive payment for answers) Unanswered questions can also be found at this URL Question Everything The latest book of science questions: unpredictable and entertaining Expect the unexpected Available from booksellers and at newscientist.com/questioneverything g these still flowed, but the north Atlantic and north Pacific would freeze solid, probably to what we know as the tropic of Cancer The northern tropical zone would be in perpetual twilight – and with no direct solar radiation would be cold, though probably less so than temperate and Arctic regions Our planet’s flora and fauna developed to take advantage of the climatic zones we have Had there been a change in tilt in the past, they would have evolved differently Moreover, any change in seasons would probably have an effect on rainfall and thus erosion patterns Peter Bursztyn Barrie, Ontario, Canada ■ In a light-hearted vein, on April 1986 The Guardian newspaper in the UK published a “Government Announcement on the proposed shift of the earth’s axis” Their supposed aim was to tilt the planet to bring the UK closer to the equator, making it warmer China would, in contrast, become a polar republic All this was to be achieved by electromagnetic charges already in orbit, but not yet switched on until 11 o’clock that morning Kitchens should be vacated, because saucepans and other items might undergo “spasmodic displacement” Alteration of zodiacal signs might cause marital mismatch and upheaval, but persons “locked in amatory embrace between 11.00 and 11.30 might feel the earth move” John Forrester Edinburgh, UK NEW SCIENTIST X INTREPID TRAVEL New Scientist and adventure specialists Intrepid travel have created a bespoke seven-day tour across Iceland Discover how fire and ice shaped the scenery – past and present – and get a chance to see the Northern Lights Highlights include: GEOTHERMAL POWERS VOLCANOES AND GLACIERS MAGICAL LANDSCAPES Marvel at the sights, sounds and smells of erupting geysers, hot springs and bubbling pools of mud Relax in the warm, mineral-rich waters of the Blue Lagoon Enjoy food cooked by the Earth’s heat, visit a geothermal power plant, and see where tomatoes grow even in deepest winter Drive across Europe’s second largest glacier in an eight-wheel truck, and see shades of blue you never knew existed in Langjökull ice cave Hike across the dramatic Sólheimajökull glacier See how an eruption 8000 years ago sculpted beautiful shapes in Vatnshellir lava cave Visit the famous Eyjafjallajökull volcano Explore UNESCO-listed Thingvellir national park, where tectonic plates rip the land apart to create a dramatic rift valley Witness the thunderous force and beauty of the Gullfoss waterfall Discover Iceland’s south shore, famous for its sheer cliffs, picturesque villages and black sand beaches overlooked by towering glaciers WHAT’S INCLUDED: ❭ Six nights’ accommodation in Reykjavik and countryside hotels ❭ Private coach ❭ Local expert guides ❭ All entrance fees DAVID CLAPP/GETTY IMAGES 25 FEBRUARY – MARCH 2017 From £1738 per person (local prices available) FIND OUT MORE Call +44 (0)142 059 3015 or visit newscientist.com/travel/iceland I I [...]... for example, funds a contraceptive trial network but still excludes under 18s “I suspect it’s political,” says Bonny, who has been running her own, small-scale 16 | NewScientist | 9 July 2016 For daily news stories, visit newscientist.com/news Sexually active girls between the ages of 15 and 19 in the US use many methods of birth control 100 80 60 SOURCE: CDC, 2011-2013 40 20 potentially setting a different... the best idea of anyone in a group.” ■ Emma Young is a writer based in Sheffield, UK 9 July 2016 | NewScientist | 29 THE RAREST OF THEM ALL YANG GUANYU/XINHUA/ALAMY LIVE NEWS When Sam Turvey stared into the face of a Hainan gibbon he knew he had to join the effort to save the world’s rarest mammal 30 | NewScientist | 9 July 2016 I has set up its territory close to the edge of the forest patch Villagers... mats of kelp, plastic – even turtles “There’s always stuff out there for them to live on,” says the study’s co-author Jonathan Waters at the University of Otago, Dunedin, New Zealand For new stories every day, visit newscientist.com/news HENRI WEIMERSKIRCH/CEBC/CNRS EASY riders The great frigatebirds can fly for weeks without a break, mostly cruising over the ocean looking for food near the surface... right way, and then you get a by gathering the fragments of Last year, a team of European for amphibians, too: at every much better view of life.” ■ Rivers of DNA 20 | NewScientist | 9 July 2016 For more technology stories, visit newscientist.com/technology Mechanical Turk to answer queries about a set of pictures, such as “What is the man doing?” or “What number of cats are lying on the bed?” Each... won’t really know what it is,” he says “It looks like a 50s sci-fi robot or something.” Conor Gearin Photographer Alastair Philip Wiper alastairphilipwiper.com 9 July 2016 | NewScientist | 25 FRANCOIS GUILLOT/GETTY COVER STORY 26 | NewScientist | 9 July 2016 ALL ABOUT ME Self-promotion comes naturally to narcissists, so should we all be stroking our egos, asks Emma Young H Everybody hates a big-head, so... – this is the stuff of every day Now a new form of synaesthesia has been discovered – one that moves beyond written language to sign language In theory, any two senses can overlap “People with synaesthesia experience the ordinary world in extraordinary ways,” says Jamie 10 | NewScientist | 9 July 2016 DIRK FELLENBERG/PLAINPICTURE Anil Ananthaswamy Ward, a neuroscientist at the University of Sussex in... conservation biologist at the Zoological Society of London 9 July 2016 | NewScientist | 31 Space raiders Companies gearing up to plunder the cosmos will blast off into a legal void How can we prevent a disastrous free-for-all, asks Paul Marks UNITED NATIONS The 1967 Outer Space Treaty left the door ajar for space mining 32 | NewScientist | 9 July 2016 M “ AGNIFICENT desolation.” Buzz Aldrin’s first... lily – as if it knew I was there – but I don’t think I’ll keep my peace lily plugged in After a while, the plant started to bother me: it’s like having a vocally disruptive child in the room Eventually, I’m forced to turn it off Penny Sarchet ■ A career in science, it’s not always what you think From movie advisor to science festival director, where will your science career take you? newscientist.com/jobs... sensations – the action is not enough by itself Most of those in the study who knew sign language were not hard of hearing and had learned to sign in later life This implies that their synaesthesia adapted to this new form of language, says Ward “It tells us that synaesthesia is not fixed in early life – exposure can bring new synaesthesia,” he says “The results are consistent with the idea that synaesthesia... first test flight with an empty Orion crew capsule in 2018 will have only half the lifting power of the retired Saturn V rockets that sent astronauts to the moon Mika McKinnon, Promontory, Utah 12 | NewScientist | 9 July 2016 Essential upgrades To get more thrust, NASA plans first to upgrade the SLS’s upper stage rocket for a second test flight in 2023, when Orion will carry a crew After that, the ... 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