New Scientist Magazine - No. 3011

32 MILEELECTRIC RANGE148MPG510 MILECOMBINED RANGEULTRA LOWCO 2 EMISSIONSWE HAVEN’T JUST MADE HISTORYWE’RE SAVING DRIVERS £1,000sThe Mitsubishi Outlander PHEV is cutting costs across the country – and if you’re one ofBritain’s average daily drivers you can use just a few drops of petrol each day.This intelligent hybrid decides when it’s more efficient to use petrol or electricity, giving it theability to deliver a staggering 148mpg 1 . With an electric range of up to 32 miles the OutlanderPHEV easily tackles the UK’s average daily drive on a single charge – and on longer journeys thepetrol engine helps out to achieve a combined range of up to 510 miles 2 . The battery can becharged in just a few hours via a domestic plug socket 3 , a low-cost home Charge Point 4 or oneof over 7,500 Charge Points found across the UK. With ultra-low CO 2 emissions the OutlanderPHEV is exempt from Road Tax and the London Congestion Charge 5 – as well as being eligible fordrastically reduced Benefit in Kind taxation 6 . There’s even £5,000 off the list price through theGovernment Plug-in Car Grant, which means an Outlander PHEV will cost you from just £28,249 7 ,the same price as the Outlander Diesel – and it comes with the same 5 year warranty 8 .We’ve made history, you just need to make time to find out how we can save you £1,000s.We call this Intelligent Motion.THE WORLD’S FIRST4WD PLUG-IN HYBRID SUVFROM £28,249 - £39,999Including £5,000 Government Plug-in Car Grant 7Discover how. Search PHEV. | Visit: mitsubishi-cars.co.uk to find your nearest dealer1. Official EU MPG test figure shown as a guide for comparative purposes and may not reflect real driving results. 2. 32 mile EV range achieved with full battery charge. 510 miles achieved with combined full battery and petrol tank. Actual range will vary dependingon driving style and road conditions. 3. Domestic plug charge: 5 hours, 16 Amp home charge point: 3.5 hours, 80% rapid charge: 30mins. 4. Government subsidised charge points are available from a number of suppliers either free of charge or for a small fee - askyour dealer for more information. Offer ends 31st March 2015. 5. Congestion Charge application required, subject to administrative fee. 6. 5% BIK compared to the average rate of 25%. 7. Prices shown include the Government Plug-in Car Grant and VAT (at 20%)and exclude First Registration Fee. Metallic/pearlescent paint extra. Model shown is an Outlander PHEV GX4h at £33,399 including metallic paint. Prices correct at time of going to print. For more information about the Government Plug-in Car Grant please visitwww.gov.uk/plug-in-car-van-grants. 8. All new Outlander PHEV variants come with a 5 year/62,500 mile warranty (whichever comes soonest), for more information please visit www.mitsubishi-cars.co.uk/warranty.Outlander PHEV range fuel consumption in mpg (ltrs/100km): Full Battery Charge: no fuel used, Depleted Battery Charge: 48mpg (5.9), Weighted Average:148mpg (1.9), CO 2 Emissions: 44 g/km.

CONTENTSVolume 225 No 3011This issue onlinenewscientist.com/issue/3011News8Future perfume:Eau de yeastDesigner bugs giveperfumers greatercontrol over scentOn the cover30Larger HarderColliderForget the Higgs.Now we’re searchingfor the root of realityCover imageMaximilien Brice/CERN(Original ATLAS image)Features38Your brainon migraineRethinking the world’smost misunderstoodneurological disorderALEX COGHE/PLAINPICTURE ALEXA BRUNET/PICTURETANK12 Shake and sniffA hand’s secret smells38 Your brain on migraineRethinking this disorder34 DambustersThe end of Brazil’shydroelectric dreams28 Gateway to addictionCigarettes and alcoholopen door to hard drugs44 Ready, aim, blur!Invisible laser impairs sightComing next week…ChanceHow randomness rules our worldLiving weaponsDid our pets hound out the Neanderthals?Leader5 Will revamped LHC make or break physics?News6 UPFRONTSyrian war linked to droughts. Amazondeforestation soars. Rendezvous with adwarf planet. Net neutrality ruling8 THIS WEEKWhy people sniff their hands afterhandshakes. Quantum foam makes distantuniverse fuzzy. Iron rain on early Earth10 SPECIAL REPORT€190 billion effort to climate-proof Europe14 INSIGHTThe vexing US law on guns and mental health17 IN BRIEFDrill Mars for ice age clues. Bees make falsememories. Future-predicting neuronsfound. Ancient Britons loved flat breadTechnology20 Buckle up for the virtual reality filmrevolution. Facebook improves onthe Turing testAperture24 Grey kangaroo frozen in red dirtOpinion26 Siege mentality Victoria Esses on the deeppsychological roots of hostility to immigrants27 One minute with… Hannah BelcherI have an autism spectrum disorder – andthere are many more women like me28 The gatekeeper Denise Kandel on howcigarettes can open door to drug addictionFeatures30 Larger Harder Collider (see above left)34 Dambusters The end of Brazil’shydroelectric dreams38 Your brain on migraine (see left)44 Ready, aim, blur! Invisible laser weaponknocks out visionCultureLab46 Mind-bending Fifty years after split brains,the mystery of the mind still eludes us47 Time to die Which theories block progress?Regulars53 LETTERS Cancer coaster. Microbial gold56 FEEDBACK Razors vs dictum57 THE LAST WORD Tree time7 March 2015 | NewScientist | 3

Big landscapesInspire big thinkingTHERE’S NOTHING LIKE AUSTRALIA FOR YOUR NEXT BUSINESS EVENT.This year we chose Australia for our global congress. It was an easy choice, as Australia’s proximity to Asia gave us theopportunity to attract many new delegates. The program was one of the best in years. New Australian developments inour field attracted a lot of interest and strong international research partnerships were established.Australia is on everyone’s list to visit, and it lured our highest number of delegates yet. There’s no doubt they’ll be talkingabout this convention for years to come.Dr Louise Wong,International Board MemberVISITAUSTRALIA.COM/BUSINESSEVENTS/ASSOCIATIONSFOR EVERYTHING YOU NEED TO PLAN YOUR AUSTRALIAN EVENT.

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A quartercenturylater, Paul Dirac conjuredup antimatter. It soon turned upin cosmic rays.And so to 2012, when jubilantphysicists at CERN’s LargeHadron Collider, near Geneva inSwitzerland, announced that theyhad found the Higgs boson prettymuch where they expected it.The discovery of the Higgsput the finishing touch to thestandard model of particlephysics. Barring a few smallwrinkles, everything this theorypredicted has now been confirmedexperimentally. But completionof the model still leaves a lot forphysics to explain, with no clearindication of where to go next.With the LHC powering upagain after a two-year refit, for thefirst time there is no consensus onwhat it should find (see page 30).If the theoreticians keep theirrun of success going, it shouldturn up the first decent evidencefor supersymmetry, the nextgenerationtheory that couldexplain dark matter, gravity andother phenomena not covered bythe standard model. But then, ifyou believe the theories, the LHCshould already have seen manysuch indications. It hasn’t.That leaves theorists andexperimentalists alike in a state ofexcitement and trepidation. Therebooted LHC could demonstratethat supersymmetry is on theright track, albeit not quite as weexpected. It could find a clutchof new particles that point in asurprising direction. Or it couldfind nothing. Either of the first“ It would be a real sadness ifthe LHC discovers nothing,because then the subject Ilove would come to an end”two scenarios would be exciting.The last looms ominously.“It would be a real sadnessif the LHC discovers nothing,because then the subject I lovewould come to an end. But ifthat’s the way the universe is,that’s the way it is,” David Tong,professor of theoretical physicsat the University of Cambridge,told the audience last month ata New Scientist event in London.If the upgraded LHC isn’tpowerful enough to makeprogress, the days of smashingprotons together to reveal thefundamental nature of realityare probably over. We could notbe confident of finding anythingnew until we reached vastlygreater energies – too great forany collider conceivable today.But there are alternatives.Some argue that messy collisionsbetween protons are not the idealway to find physics beyond thestandard model. Plans alreadyexist for more precise electroncolliders – from the InternationalLinear Collider, which might bebuilt in Japan, to a circular colliderat CERN up to 100 kilometreslong – far bigger than the LHC.Our quest to understand thenature of reality thus stands ata crossroads. Past success hasbred confidence in the BigPhysics approach. Governmentagencies, emboldened by theexcitement of discovery and theemergence of spin-offs like theWorld Wide Web, have been happyto spend billions of dollars onparticle experiments. But if theLHC comes up with nothing,will the confidence still be thereto fund the next generation ofmachines?Many physicists would claimthat their success over the yearsowes more to judgement thanluck. Now, without the steadyhand of agreed theory to guidethe way, they may need all theluck they can get. ■7 March 2015 | NewScientist | 5

UPFRONTSyrian war’s dry rootsTHE consequences of leaving on your climbing carbon dioxide emissionslights might be worse than you think. (PNAS, doi.org/2jw).A drought exacerbated by climateThose natural yearly variationschange might have contributed to led to the occasional drought, butthe outbreak of civil war in Syria. the long-term drying exacerbatedColin Kelley of the University of the 2007-2010 drought, making it theCalifornia, Santa Barbara, and his most severe in the observed record,colleagues analysed Syrian weather says Kelley. The drought and andata since 1931, and found that the inadequate response to it led to cropwinter rainfall that is crucial for crops failure, a rise in crop prices and masshas steadily declined. Over the same migration into slums with few jobperiod, temperatures have risen, opportunities. Affected cities includeddrying soils faster. The onlyHoms and Hama, where protestsexplanation lies in humanity’sbegan in 2011.greenhouse emissions, says Kelley. “Placing stress on a society tendsClimate models, his team found, to make violence more likely,” sayspredict such changes for the region. Andrew Solow of the Woods HoleThe team used statistics to tease Oceanographic Institution inapart annual ups and downs inMassachusetts. But, he says, politicalprecipitation from the long-term unrest in the Middle East might havedrying that seems to be linked to led to violence in Syria anyway.–Caused by climate change?–UNITED NATIONS RELIEF AND WORKS AGENCY VIA GETTY IMAGESDwarf world DawnCROSS dwarf planets off thebucket list. As New Scientist wentto press, NASA’s Dawn spacecraftwas on track to arrive at Ceres,which will become the first dwarfplanet to get a spacecraft visitor,early on 6 March. The icy worldmay hold clues as to how our solarsystem came together.Dawn previously orbitedthe asteroid Vesta, and tookoff in 2012 to chase Ceres, a950-kilometre-wide object inthe asteroid belt. The arrival will“The arrival will set apersonal record for Dawn,making it the first to visittwo different worlds”set a personal record for Dawn,making it the first spacecraftto visit two different worlds.The spacecraft should swinginto orbit around Ceres at 4.20 amPacific time, but NASA scientistswon’t be able to confirm successuntil the afternoon, when thespacecraft will be in the right spotto send signals back to missioncontrol. Dawn will orbit the dwarfplanet for a year. During this time,the craft will gather informationabout Ceres’s unique features,particularly subsurface geologicalprocesses, in an effort to learnmore about it and about the rolethat similar objects had in theformation of the solar system.The mission will also providea closer look at a strange sight inone of Ceres’s craters: two brightspots, recently imaged by Dawnon its approach. The spots havepuzzled NASA scientists, whobelieve they may be ice or salts,or perhaps related to the faintplumes of water vapour detectedby the European Space Agency’sHerschel spacecraft early last year.Although Dawn’s instrumentsare not designed to confirm thevapour finding, they may beable to observe it indirectly.“The mystery will be solved,but it’s one that’s really got uson the edge of our seats,” saidCarol Raymond, Dawn’s deputyprincipal investigator, at a pressconference on Monday.The more famous dwarf planetPluto will have to wait for its timein the spotlight: the New Horizonsspacecraft will arrive there in July.Flu, man flu or cold?ATISHOO! Chances are that ifyou’re 30 or over, it’s just a cold.That’s the message from workshowing that people aged 30 orover can expect just two bouts offlu per decade. Children are likelyto succumb every other year. Thismay be because adults have betterimmunity or mix less with others,says Steven Riley of ImperialCollege London. His team screenedblood samples from people insouthern China for antibodies toseasonal flu strains that circulatedglobally between 1968 and 2009.An algorithm then worked outin which years each personhad become ill (PLoS Biology,DOI: 10.1371/journal.pbio.100208).But things could change. TheWorld Health Organization haswarned of a rising number of avianflu strains emerging over the pasttwo years. “This appears to behappening now at an acceleratedpace,” it said. The worry is that thestrains could infect humans: “Theconsequences for human healthare unpredictable yet potentiallyominous,” it concluded.World’s most infectious dressAN INEXPENSIVE dress worn toa wedding in Scotland turned outto be a highly contagious virus.A Tumblr user uploaded a pictureof the dress, saying she was havingan argument about what colour itwas: white and gold or blue andblack. Buzzfeed republished it andit broke the site’s record for visitorsto a web page. Practically everymedia outlet and dozens ofcommercial enterprises rushed topiggyback on the phenomenon, andon Friday there was even less senseto be had out of the internet thannormal. Blogger and viral-contentexpert Neetzan Zimmerman tweetedthat it was the “viral singularity”.As for the dress itself, cognitivescientist Erin Goddard at MacquarieUniversity in Sydney, Australia, toldNew Scientist the confusion over itscolour came about because peoplewere unconsciously correcting forthe colour they assumed the sourceof light on the dress to be.6 | NewScientist | 7 March 2015

For new stories every day, visit newscientist.com/news60 SECONDSFreedom on the netYOU don’t often see dancing inthe streets of the US capital. Butlast week, campaigners for “netneutrality” apparently did so,after the Federal CommunicationCommission (FCC) voted in“I think the nearly 4 millionpeople who wrote in to theFCC is the most significantpiece of the equation”favour of rules to classifyinternet service as a utility.The new regulation, which willapply to US broadband providers,is seen as crucial to ensure thatall information is treated equallyin transmission – so-called netneutrality. This has beendescribed as a human rights issue.Victor Pickard of the Universityof Pennsylvania says widespreadpublic engagement in the issuewas instrumental to the outcome:“I think the nearly 4 millionpeople who wrote in to the FCCis certainly the most significantpiece of the equation.”But a Republican-led FCC ofthe future could overturn thedecision, adds Pickard. Indeed, thecurrent rules are already expectedto be challenged in court. “I feelmany people are declaringvictory,” he says, “and once youhave the public tuning out that’swhen the damage could occur.You might see some pushbackagainst these regulations.”–You too can own this meme–AP PHOTO/RUI VIEIRADeforestation riseTIMBER! Deforestation in theAmazon has skyrocketed in thepast six months.That’s according to an analysisof satellite images issued byBrazil’s non-profit researchinstitute, IMAZON. It comparedmonthly deforestation figureswith the same month a year before.The difference ranged from a136 per cent increase in Augustto a 467 per cent rise in October.“If this trend continues,it won’t be long beforethe world’s tropical forestsare essentially gone”“Rates have way more thandoubled over the equivalentperiod in the previous year,” saysPhillip Fearnside, an ecologist withBrazil’s Amazon research agencyINPA. And the study probablyunderestimates the problem,because the satellite used canonly recognise clearings largerthan 250,000 square metres.Many farm plots are smaller.The figures come as a surprisegiven that deforestation in theBrazilian Amazon declined by77 per cent between 2004 and2011 (PNAS, doi.org/wbn).Brazil’s Amazon isn’t an isolatedcase, though. A study releasedlast week shows that the loss oftropical forests around the globe–Now you see it, now you don’t–between the 1990s and 2010accelerated by 62 per cent(Geophysical Research Letters, doi.org/2h7). “The rate of deforestationis way up,” says the lead author oflast week’s study, Do-Hyung Kimat the University of Maryland.“If this trend continues, it won’tbe long before the world’s tropicalforests are essentially gone.”For more on the Amazon, see page 34Hitch a rideCALLING all galactic hitchhikers:the European Space Agency isoffering a ride. In 2020, ESAplans to launch a spacecraft toan asteroid, and will have roomfor up to six mini-spacecraftcalled CubeSats onboard.These 10-centimetre-widevessels are cheap to build, but noCubeSat has ever flown beyondEarth’s orbit, so it could be achance to grab a slice of history.ESA is inviting applicationsfrom research teams andcompanies across Europe.Although even hobbyist teamscan build CubeSats, JamesDiCorcia of Deep Space Industries,a firm that is also working on aCubeSat mother ship, thinks ESAwill be looking for experiencedlaunchers. But even simplespacecraft will come in handy.“At this early stage in asteroidproximityoperations, almost anydata acquired is useful,” he says.PAULO PEREIRA/GREENPEACEEurope’s hard line on GMPreventing farmers from growinggenetically modified crops just gota lot easier in the European Union.Member states previously had tojustify proposed bans with scientificevidence of potential harm to healthor the environment. But now, rulespassed on Monday mean bans can beinvoked for a host of other reasons.Swiss ice breakerSwitzerland officially submittedits post-2020 climate action planto the UN this week, making it thefirst country to do so ahead of theinternational climate summit inParis in December. It plans to reduceits greenhouse gas emissions tobetween 70 and 85 per cent below1990 levels by 2050.Kew Gardens croppedThe UK government must urgentlygive the Royal Botanic Gardens atKew in London more financialfreedom to protect its scientificresearch, after almost 50 scientistswere made redundant there. Therecommendation came in a reportby the House of Commons Scienceand Technology Committee,published on Wednesday.Orbital explosionIn space no one can hear youboom. A US military satellite hasexploded after 20 years in orbit. TheDMSP-F13 satellite was launched in1995 to gather weather data for theair force and navy, but was no longerin full-time operation. Its powersystem overheated at some point inFebruary, blowing it to smithereens.Emotional popcornTrying to shed the pounds?Think twice about that tearjerker.Moviegoers across seven US citieswho watched the sad film Solarisate an average of 55 per cent morepopcorn than those watchingcomedy My Big Fat Greek Wedding,say researchers from the CornellUniversity Food and Brand Lab(JAMA Internal Medicine, in press).7 March 2015 | NewScientist | 7

THIS WEEKYeast’s heavenly potentialGenetically modified microbes could oust flowers in the making of perfumeAviva RutkinSITTING before me is a vial ofcloudy white broth. BiologistPatrick Boyle invites me to takea sniff. To my amateur nose, theliquid smells green and sweet,a little like fresh-cut grass, a littlelike a bunch of flowers.The concoction is a microbialperfume. Cooked up in thelaboratories of Ginkgo BioWorksin Boston, it contains yeast thathas been genetically engineeredto smell of roses. Its ultimatepurpose: to become part of a$10 to $100 a kilo because there’s ashortage or an embargo,” says BobWeinstein, chief operating officerat Robertet.Perfumers can use a syntheticsubstitute, created by mixingfour or five chemicals together toapproximate natural rose scent.This can be convincing, but someperfumers say it falls short of therich subtleties that woulddistinguish a high-end fragrance.Culturing microbes to producescents is not only cheaper thanusing naturally sourcedingredients, but also givesperfumers more control overfragrances, says Ben Fundaro,director of perfumery at Robertet.“We’re basically at the mercy ofnature with some of these crops,”he says. “If we could produce in amore controlled environment, theodour would be more consistent.”The approach being pursued atGinkgo starts with the DNA of therose itself. In order to make thecompounds responsible fortheir flowers’ distinctive smell(see “On the scent of a rose”, right),“ We’re at the mercy ofnature with roses. Culturedproducts would give us amore consistent odour”designer fragrance, one where itspresence rivals the rose oils oftenused in luxury scents.The “cultured rose” wasborn out of a marriage betweenGinkgo – which bills itself as “theworld’s first organism engineeringfoundry” – and Robertet, a Frenchflavours and fragrance companyfounded in 1850. Robertet pridesitself on the natural ingredientsit uses in perfumes created forclients such as Chloé and BottegaVeneta, as well as its scents forhousehold products like detergents.Rose oil is a classic perfumecomponent. Traditionally,roses are grown in vast fields inBulgaria or Turkey, then pickedby hand and distilled to extractthe aromatic oil. But from thefragrance companies’ perspective,this approach is unreliable. Boththe quality and the price of rosescan fluctuate wildly from year toyear, influenced by factors suchas natural disasters, labourshortages, diseases or simply apoor growing season. “You haveraw materials that will go fromALEXA BRUNET/PICTURETANK8 | NewScientist | 7 March 2015

In this section■ The €190 billion effort to climate-proof Europe, page 10■ Why people sniff their hands after handshakes, page 12■ Facebook improves on the Turing test, page 22plants need to use enzymes,and the team must find the genescoding for these. Once that’s done,Ginkgo can engineer a numberof strains of yeast, each with agenome modified to ensurethat the microbes’ metabolicreactions result in one of thedesired compounds. This mightbe accomplished by tweaking thegenome or by adding genes froma rose or another plant, such ascorn or hyacinth, that does thesame job.“Our goal is to recreate the rosebiosynthetic pathways, even if wedon’t use rose genes to do it,” says–Much easier to just leave it to proveBoyle. “We often find that adifferent but highly related genefrom a different species worksbetter in yeast than the rose genethat has the function we want.”Every month or so, Ginkgosends samples of the strainsto Robertet perfumers. Theyevaluate them and send critiquesback to Ginkgo, asking for a scentto be made stronger or weaker,or to play up its floral, musky orfruity qualities. Once the strainsfor the individual componentshave been cleared by theperfumers, Ginkgo will produce asingle strain of yeast that has allthe genetic modifications – theirattempt at the ideal rose scent.The best rose oil, says Fundaro,smells fresh and clean, “very trueto the way the rose would smell inthe air if you were in a rose gardenor next to a bouquet”. One issuewith the cultured rose fragranceis that it retains the yeast’scharacteristic sour smell. BeforeBoyle’s team is done, they mustfind a way to downplay thisodour, perhaps by moderatingsome of the genetic pathways thatcontribute to it, or by carefullyfiltering the final product.Ginkgo isn’t the only companyto have anticipated manufacturers’desire for cultured fragrances andflavours. Californian companyAmyris has partnered with Swissfirm Firmenich to work on labmadepatchouli oil. Allylix,another California company,cultures a version of vetiver oil,a woody extract of an Indianperennial grass.“The basic material is sugarand microorganisms, so it’s muchmore stable,” says Toine Janssen,CEO of Isobionics, based in Geleenin the Netherlands. Isobonicsrelies on bacteria to makevalencene, a compound found inoranges and often used in softdrinks. “It’s like brewing beer. Ifyou have lots of fermenters, youcan make as much as you like.”Shota Atsumi, a chemist at theUniversity of California, Davis,sees another potential upsideto cultured products: they mayON THE SCENT OF A ROSEWhy does a rose smell like a rose?To uncover the secrets of a flower’sscent, chemists use a techniquecalled headspace analysis. Theylock the plant in an airtight glasscontainer, trapping the volatilecomponents responsible for its smell.It’s then easy to do tests to identifyeach compound and measure itsconcentration.Headspace analyses have revealedhundreds of compounds among thedifferent rose varieties. The mostcommon contributors to the classicrose smell are:replace some synthetic scents,the vast majority of which areproduced from petrochemicals.Last year, in an effort todemonstrate the potential ofcultured scents as a renewablealternative, Atsumi’s researchteam altered the DNA of E. colito make the bacteria smell likebananas and blueberries.It’s not clear what customerswill make of a microorganismculturedperfume. VictoriaFrolova, a perfume industryanalyst, says companies maychoose not to highlight theunusual product process on thelabel. “For reasons of intellectualproperty, the fragrance industry“ Can we recreate an extinctflower’s scent? We’vesequenced Neanderthals,so it’s not out of question”doesn’t share the componentsof perfume, much less how theyare synthesised,” she says. “Howwould anyone know that themolecules in their eau de toiletteare yeast-produced?”As researchers get better atproducing cultured fragrances,they may become moreadventurous, attemptingto replicate much scarceringredients. Many naturalfragrances prized by perfumersare extremely difficult to get holdof: compounds from jungleCitronellol Also found in citronellacandles. Imparts a sweet smell.Geraniol Strengthens the rose scent.Nerol Makes roses smell fresh.Farnesol This sweet-smellingcompound in combination withthe three above give roses theircharacteristic smell.Linalool Often used in cleaningproducts with floral fragrances.Eugenol Also found in bay leavesand clove oil, it has a spicy smell.Rose oxide Has a grassy smell;strengthens roses’ initial fragrance,or top note.orchids that resist cultivation, forexample. Another rare ingredientis ambergris, an earthy substancemade inside a sperm whale’s guts;people collect it whenever itwashes up on the beach. Thesecould one day be cultured bycomparing the genomes of theiranimal and plant sources to onesalready on tap in the lab.Or fragrance companies couldturn to bioengineers to ordercustom-grown versions of scents.This is the idea that excites MartinGras, a perfumer for over 40 years.“Perfumers get inspired bynature,” says Gras. “I can imaginewith genetic engineering, youcan make new odours just bychanging the genes of the flower.It is another way of thinking.”The biologists at Ginkgo planto push these boundaries. Theyare now seeking samples of IceAge wildflowers that have beenpreserved in permafrost. If thesurviving DNA fragments containgenes present in modern-dayplants, researchers may be ableto develop a yeast strain thatmimics the extinct plants’ longlostfragrances.“Can we recreate the scentof flowers that can’t be grownbecause they don’t exist anymore?” asks Boyle. “People havesequenced Neanderthals, so it’snot out of the question.” ParfumExtinctio, the ultimate elitefragrance. ■7 March 2015 | NewScientist | 9

SPECIAL REPORTClimate-proofing EuropeCan €190 billion save Europe from the wrath of climate change?Andy CoghlanAS CHAOS from climate changeramps up in the coming decades,making floods, droughts andheatwaves commonplace, Europewill be ready. So says the EuropeanEnvironment Agency, whichlaunched its five-year assessmentof the state of Europe’senvironment in Copenhagen,Denmark, this week.A key message is that we mustprepare now for the catastrophesthat will become more frequent ifthe world warms up as predicted.“Many of the decisions we maketoday will determine how we aregoing to live in 2050,” said HansBruyninckx, executive director ofthe agency, at the launch of TheEuropean Environment State andOutlook 2015.Unlike other rich nations suchas the US and Australia, Europehas embraced the reality ofclimate change and is blazing atrail in preparation for what is tocome. The European Union hasagreed to spend 20 per cent of itsbudget of €960 billion for 2014to 2020 on mitigating climatechange and adapting to itseffects. The money is expectedto boost efforts to climate-proofEurope. “Countries must decidewhat to use it on, and makesure it’s used properly,” saysBacterial cell walls,antibiotics and theorigins of life2015 Leeuwenhoek Prize Lecturegiven by Professor Jeff ErringtonFMedSci FRS, Newcastle UniversityTuesday 17 March, 6.30pmThe Royal Society6 – 9 Carlton House Terrace, London, SW1Y 5AGFree admission – doors open at 6pmFor more information visit royalsociety.org/eventsRegistered Charity No 207043. DES3577Stéphane Isoard, the agency’sspecialist on adaptation toclimate change.Dozens of projects are alreadyin various phases of readinesswith the help of earlier funding.The top reason cited by 28 out of30 national authorities for going“ Many of the decisionswe make today willdetermine how we aregoing to live in 2050”ahead with such projects is theimpact of previous extremeweather events, according toa survey published in October.Next, for 17 out of 30, came theheavy economic costs of stormor flood damage. For example,the European Commissionestimates that between 1980and 2011, floods killed morethan 2500 people and adverselyaffected another 5.5 million inEurope, while causing economiclosses exceeding €90 billion.As a result, 13 countries nowhave adaptation projects upand running, and another 33have action plans or nationaladaptation strategies in place.Here, we showcase some of 60or so projects from across thecontinent (see right).Whether they will ultimatelybe enough to protect peoplein Europe will depend on thevagaries of climate change. Butthe costs of doing nothing couldbe even greater. The EC estimatesthat the annual cost to the EU ofnot adapting to climate changecould rise to €100 billion by 2020and €250 billion by 2050. Isoardcan’t say if it’s possible to climateproofour future, but given thesuccess of flood managementplans, for example, theintroduction of the new projectsis “clearly a very positive sign”. ■1 SOGN OG FJORDANEMOUNTAINS, NORWAYHAZARD: Avalanches, landslidesand floodingSOLUTION: Early warning system.Warmer winters and unstabletemperatures can cause rock slides andavalanches in unexpected locations,such as populated areas and roads.The scheme in this county aims toalert citizens and tourists at immediaterisk from such hazards via landline andcellphone-based messaging systems,and social media, including Facebook.COST: €105,0002 NORFOLK BROADS, UKHAZARD: Flooding from tidal surgesSOLUTION: Reinforce banks. Brandedas “Britain’s Magical Waterland”the Norfolk Broads are uniquewetlands where flooding is likely atneighbouring properties and farmlandthrough breaches in old peat and clayembankments. The project aims to10 | NewScientist | 7 March 2015

For daily news stories, visit newscientist.com/newsForest fireHeatwaveFloodAvalanche/landslideDroughtstrengthen and modernise 175kilometres of embankments to keepcurrent and future settlements safe.COST: €160 million3 NIJMEGEN, THENETHERLANDSHAZARD: River floodingSOLUTION: Get rid of the bottleneckin the Waal river, which bends sharply62113 47–Submerged, but not without hope–58910and narrows as it meanders aroundthe coastal city of Nijmegen, causingfloods. For example, in 1993 and 1995a quarter of a million people had to beevacuated. The city is digging an extrachannel, essentially broadening theriver, giving it more room to flow. Thiswill also create an urban island withnew spaces for riverside recreation.COST: €350 million9CLOCKWISE FROM LEFT: CHRISTOF STACHE/GETTY; ANDY BRANDL/GETTY; JOHN KOLESIDIS/REUTERS4 BERLIN, GERMANYHAZARD: Urban heatSOLUTION: Grow vegetation whereverpossible, including on roofs and walls,to provide shade and cool the city.Under the scheme, 60 per cent ofnewly built public and residential areasand 30 per cent of business areas inthe inner city must be reserved as“green space”.COST: Not available5 LODZ, POLANDHAZARD: Storm floodingSOLUTION: Provide a “sponge” forincreasingly heavy rainstorms byrestoring the city’s natural rivers andby building new reservoirs. During19th-century industrialisation, riverswere turned into canals that don’tsoak up water as well, which ledto increasingly severe floods.COST: €1.15 billion6 ZARAGOZA, SPAINHAZARD: DroughtSOLUTION: Make Zaragoza’s 700,000inhabitants more water-savvy tosurvive the lengthier droughtspredicted for the region. Coupledwith anti-leak repairs, the projecthas almost halved daily water useper person compared with 1980, andthe city’s total water consumptionhas fallen by 30 per cent since 1995.COST: €2.5 million, for the publicinformation campaign7 VENICE, ITALYHAZARD: Storm surges and risingsea levelSOLUTION: Build four mobile barriersat the three points where water fromthe Adriatic Sea enters the lagoonon which Venice is built. The barrierscould be temporarily raised to blocksea surges and protect against risesof up to 60 centimetres.COST: €4.5 billion8 FORMER YUGOSLAVREPUBLIC OFMACEDONIAHAZARD: HeatwavesSOLUTION: Raise awareness. In 2007,a record heatwave in the landlockedBalkan country reached 45.7 °Ccausing an estimated 1000 deaths.The national action plan aims to raisepublic awareness and prepare thehealth sector to identify vulnerablecitizens, and advise them on how toavoid the impact of severe heatwaves.COST: Not available9 CYPRUS AND GREECEHAZARD: Forest firesSOLUTION: Fire analysis system. Aroundthe Mediterranean forest fires havedoubled in frequency since the 1970s,to 50,000 a year. To cope, firefightershave been testing a system to predicthow a blaze will evolve. It integratesa range of data such as vegetationcover, landscape information, ignitionrisk and real-time weather feeds.COST: €2.3 billion10 DANUBE RIVER:BULGARIA, MOLDOVA,ROMANIA, UKRAINEHAZARD: River floodingSOLUTION: Soak up flood waterby restoring 224,000 hectares ofwetlands flanking 1000 kilometresof the river Danube. The wetlandswere lost over the past centurythrough dyke drainage projectsin the four countries. The LowerDanube Green Corridor project aimsto protect 1 million hectares of landcurrently vulnerable to flooding.COST: €183 million7 March 2015 | NewScientist | 11

THIS WEEKShake hands, sniffpalm, read signalsCatherine de LangeYOU won’t believe you do it, butyou do. After shaking hands withsomeone, you will lift your handsto your face and take a deep sniff.This newly discovered behaviour,revealed by covert filming,suggests that humans usebodily smells to send signals,much as other mammals do.There is evidence that thescent of women’s tears lowerstestosterone levels and dampensarousal in men, and that humansweat can transmit fear. Buthumans don’t tend to go aroundsniffing each other, so how can weexchange information via smells?Noam Sobel and his colleaguesat the Weizmann Institute ofScience in Rehovot, Israel, turnedto one of the most common wayspeople touch each other: shakinghands. “We started looking atpeople and noticed that after,the hand somehow inadvertentlyreached the face,” says Sobel.To find out if people reallydo smell their hands, histeam surreptiously filmed 153volunteers. Some were wiredup to a variety of physiologicalinstruments so that airflow to theSAUL LOEB/AFP/GETTY IMAGESnose could be measured withoutthem realising this was the aim.The volunteers were filmedas they greeted a member of theteam, either with or without ahandshake. The researchersrecorded how often volunteerslifted their hands close to theirnose, and how long they keptthem there, during the minutebefore and after the greeting.Before the greeting, both menand women had their hands neartheir nose 22 per cent of the time,on average. Airflow in the nosemore than doubled at the sametime, suggesting they were indeedsmelling their hands.After shaking hands withsomeone of the same sex, bothmen and women sniffed theirshaking hand for more than twiceas long as they did before thehandshake. If the person was ofthe opposite sex, they smelledtheir other hand twice as long asbefore (eLife, doi.org/2jz).–Scent a deal? Not always–The team also carried outthe experiment with one of thepeople wearing sterile gloves.The chemicals picked up on theglove included hexadecanoic acidand squalene, both of which areinvolved in social signallingamong dogs and rats.It may seem counter-intuitivethat the volunteers smelled theirshaking hand more when theyencountered someone of thesame sex, but that’s the wrongway to think about it, Sobel says.“We tend to think of socialchemosignalling as a cross-genderstory, but it’s not.” There areplenty of instances wheresignalling happens betweenpeople of the same sex, he says,such as when women’s menstrualcycles become synchronised.The behaviour could also dependon the context, he suggests. In abar, for example, the patternmight be reversed.One surprise was just howmuch the volunteers smelledtheir hands. “When we werecoding the videos we would seepeople sniffing themselves justlike rats,” says Sobel. “It’s likeblindsight – you see it all the timebut you just don’t think of it.”Charles Wysocki at the MonellChemical Senses Center inPhiladelphia says that thefinding fits with the generalidea that there is a lot morechemical communicationgoing on than we are aware of. ■Key to quantumgravity may lurkin cosmic hazeSPACE-TIME’S frothy nature could beblurring the cosmos. If our views ofgamma-ray bursts halfway acrossthe universe are intrinsically fuzzy,as some predict, then the findingcould help unite the twin pillarsof theoretical physics: quantummechanics and general relativity.The two theories disagree aboutthe texture of the universe, withrelativity saying space-time is smoothand quantum mechanics claiming itis grainy, especially on small scales.Peacemaking “quantum gravity”schemes, like string theory, arenotoriously hard to test, but dopredict that space-time shouldbe frothy at close range.This “quantum foam” would onlyshow up at scales of 10 -35 metres,far too small to observe directly.But it might jostle the paths ofphotons enough for us to observeits effects across the universe.“They’re very small perturbations,but they add up,” says Eric Steinbringof the National Research CouncilCanada in Victoria.In 2003, Richard Lieu at theUniversity of Alabama in Huntsvillelooked for this blurring in opticalimages of galaxies from the Hubblespace telescope, but found nothingsignificant. Others have since arguedthat our ability to observe far moredistant objects at all means the foam’seffects must be weak or non-existent.“ Quantum foam might jostlephotons’ paths enough forus to observe its effectsacross the universe”But Steinbring says that highenergyphotons – belonging to gammarays and X-rays – could be perturbedby even weaker fluctuations inthe quantum foam (arxiv.org/abs/1502.03745). He tweaked theequations that describe how tinyuncertainties due to the foamadd up as a photon crosses space,and compared his predictions withgamma-ray data from NASA’s Fermitelescope. The results are consistentwith some blurring, he says.“I take it as a promising result,” saysLieu. “Quantum gravity is the ultimatein excitement.” Joshua Sokol ■12 | NewScientist | 7 March 2015

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IN BRIEFBAERTELS/PLAINPICTUREDrat! Where’s the nectar?I was sure it was this flowerEVER remembered something that turned out to befalse? Bumblebees may be prone to similar lapses.Although bees have good memories, they have a lotto recall, including the colours and locations of flowers.“Bees make more mistakes when they juggle multiplememories than if they just focus on one flower type,”says Lars Chittka of Queen Mary University of London.Chittka and his colleague Kathryn Hunt investigatedwhether bees make false memories, as humans often do.This happens when an individual remembers somethingthey haven’t actually experienced – a problem forTreating inherited disease in the wombBABIES with a genetic disease mayface a lifetime of treatment. Butwhat if the baby’s immune systemcould be primed for treatmentbefore they were born?Our immune systems areusually good at destroying foreignmaterial in our bodies. But thisdoesn’t apply in the womb: astudy in the 1950s showed thatmice undergoing skin grafts fromdonor mice were more likely toaccept it if they had been exposedto the donor cells as fetuses.Sébastien Lacroix-Desmazesat INSERM in Paris and hiscolleagues wondered if this couldhelp treat inherited diseases, suchas haemophilia. This is causedby the lack of a clotting proteinand can be treated with proteininjections. But in some cases, theprotein is rejected by the immunesystem. To see if fetal primingwitnesses in trials and for students, who maymisremember what they were taught.The researchers trained bees using artificial flowersthat were either yellow or had a black-and-white ringedpattern. The flowers offered a nectar-like reward, but atdifferent times. When tested within minutes of theirtraining, bees usually visited a flower of the type that hadmost recently rewarded them. But as time wore on, somebees started opting for a completely new type of flower –one with yellow and white rings. The bees seemed tohave become confused, merging their memories tocreate a false one (Current Biology, doi.org/2gp).”There might be items in a bumblebee’s memorylibrary that they have never actually encountered inreal life,” says Chittka.could help, the team gave clottingprotein to pregnant mice bred tolack it. Other similar pregnantmice received no treatment.Once the pups were born,all were treated with proteintherapy. The mice primed inthe womb were much moretolerant of the protein – theirimmune systems produced80 per cent less antibody againstit than the unprimed mice(Science Translational Medicine,doi.org/2c5).Artificial fibre astough as spider silkSPIDER silk is stronger than steeland tougher than Kevlar, butefforts to spin our own have sofar failed to match the real thing.Now a German research grouphas equalled its toughness.Previous attempts to mimicspider silk have focused on twomolecules that provide its materialproperties. But Thomas Scheibelat the University of Bayreuth inGermany and his colleaguesrealised that this neglected twosmaller molecules that help alignthe strands. His team splicedspider genes into E. coli, whichenabled the bacteria to produce allfour molecules in a bath of alcoholand water. The team then used amethod called wet spinning todraw out the fibres, creating theartificial silk (Advanced Materials,doi.org/f253cq).The material is not as strongas real silk, but is more elastic,so it can absorb as much energyas the real thing.Programmablepop-up materialsNORMALLY you can rely on solidobjects to hold their shape. Butnow there’s a way to make flatsurfaces pop into complex 3Dshapes when heated – which couldfind uses from medicine to flight.Taylor Ware at the Wright-Patterson Air Force Base in Ohioand team created a film of elasticpolymers that contains a crystallattice. Shining polarised laserlight on the film changes the waythe lattice is aligned, and can beused to draw a pattern. Becausethe crystal’s thermal propertiesaren’t the same in all directions,heating the film to 175 °C makessome parts of the pattern expandand others contract. Thepreplanned 3D shape formed canbe 100 times as tall as the film isthick (Science, doi.org/2gz).7 March 2015 | NewScientist | 17

IN BRIEFFor new stories every day, visit newscientist.com/newsBRIAN J. SKERRY/NATIONAL GEOGRAPHIC CREATIVEGreat whites plotattacks using sunDAA DUM! Daa dum! Great whitesharks attack by positioningthemselves between the blindingsun and their unsuspecting prey.It is the first empirical evidenceof a non-human animal using thesun as part of its hunting strategy.Charlie Huveneers at FlindersUniversity in Australia andcolleagues threw chunks of tunainto the water in South Australiaand watched how the sharksapproached when attacking.They recorded 44 great whitesharks making 1000 approaches,37 of which were actual attacks.Sharks tended to come in from thedirection of the sun: in the morningthey were more likely to attackfrom the east and in the eveningfrom the west. When the sun washidden by cloud, there was nosuch association (The AmericanNaturalist, doi.org/2gv).It could be that the prey arebetter lit that way, or perhaps theirview of the shark is obscured bythe glaring sun. “With the sun inthe eyes of the prey, their pupilscontract,” says Rob Harcourt atMacquarie University in Sydney,Australia.“I surf every day at Bondi [beach]and in the mornings the sun is risingover the water,” says Harcourt.“The sun is a lot brighter above thewater so hunting that way wouldmake sense.”Future-predicting neurons discovered in the brainLEAN in for a kiss. Am I into it orwill you get a slap? Interactingsocially requires us to predictothers’ intentions. Now we knowwhich brain cells allow monkeys –and possibly humans – to do this.Keren Haroush and ZivWilliams at Harvard MedicalSchool trained monkeys to play aversion of the prisoner’s dilemma,a game used to study cooperation.The reward – in this case, drops ofjuice – depends on whether or notboth parties individually opt tocooperate. Once both monkeyshad made their decision, theyPrehistoric Britonsloved flat breadPREHISTORIC people living onthe British Isles were more thanhunter-gatherers: they werebakers, too. They seem to havebeen eating wheat 2000 yearsbefore arable farming startedon the islands.Robin Allaby at the Universityof Warwick, UK, and his teamfound wheat DNA dating backsome 8000 years in mud at a nowsubmerged Mesolithic shipyardnear the Isle of Wight, off thesouthern coast of the UK (Science,doi.org/2gs).But no pollen turned up,which suggests that the wheatwasn’t being grown there. A lackof husks and seed casings alsoimplies the wheat wasn’t groundat the shipyard, and was insteadimported as flour.The closest wheat farmersat this time were probably insouthern Europe or the NearEast. “Rather than being cut off asthe commonly held view states,these hunter-gatherers had tradelinks to distant agriculturalcommunities,” says Allaby.It is likely that the boat buildershad a fondness for flat breads tocomplement their protein-richdiet of game and foraged nutsand plants, says Allaby.could each see the other monkey’schoice. Like humans, theywere more likely to cooperateif their opponent had recentlycooperated with them.During the experiment,Haroush and Williams recordedbrain activity from single cells inthe monkeys’ anterior cingulate –an area involved in decisionmaking.They found that theactivity of a specific set of neuronswas associated with the monkey’sown decision in each game.But anticipating an opponent’saction is key to maximising theFor clues to Earth’s climate, drill MarsDIGGING a hole on another worldmay settle a nagging question aboutEarth’s climate.From about 1300 to 1870, much ofthe Earth endured a long cold snapdubbed the Little Ice Age. The freezeis usually blamed on a dip in solaractivity, but there are other suspectssuch as volcanoes.If the sun was responsible, weshould see evidence of it across thesolar system, says Ralph Lorenz ofthe Johns Hopkins University AppliedPhysics Lab in Laurel, Maryland.To settle the debate, he suggestsdigging a hole on Mars to see if it, too,reward. The pair found anotherset of neurons in the same areathat seemed to predict what amonkey’s opponent intendedto do – before they did it.In fact, when they looked backat the results, in 79 per cent oftrials, the activity of the neuronsin one monkey predicted thenext move of the other (Cell, doi.org/2gn). They say that unlikemirror neurons – which are activewhen observing an action orperforming the same action asanother – these neurons try topredict the intentions of others.had an ice age around that time(Icarus, doi.org/2g2). Temperaturechanges propagate downwardthrough ice and soil, so a boreholewill contain clues to past climate.The ice cap in Greenland containssignals of the Little Ice Age around60 metres deep, for instance.Drilling a hole on Mars is already onthe cards: NASA’s 2016 InSight landerwill drill 5 metres into Martian soil.That might be deep enough to finda hint of an ice age. For the fullsignature you would need to digdown 40 metres, but it could bemuch shallower in certain soils.NASA/JPL-CALTECH/MSSS18 | NewScientist | 7 March 2015

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TECHNOLOGYHOLLY ANDRES/HELLO ARTISTS–Film night of the future–Enter the reel worldThe virtual reality boom is about more than just gaming –it could revolutionise how we watch films. Jacob Aron jacks inI’M SAT in a deckchair relaxingon the beach, watching the sun godown. I would happily have stayedthere for a good while, but mytime is up and I have to returnto the real world. When I removethe Oculus Rift headset andheadphones, the noisy conferenceroom comes as a huge shock.I had been experiencingPerfect Beach, a virtual reality (VR)experience created by developernDreams in Farnborough, UK.The firm was showing off itscreation at the SouthWest VRconference in Bristol last week,where game developers,film-makers and visual-effectsartists came together to discusshow VR experiences couldimprove films and games.The rise of VR headsets inrecent years has been led bygame developers seeking a wayto immerse players even deeperin virtual worlds. But addingVR to a video game can actuallyhamper play, because the gogglesstop you seeing the controller inyour hands.Yet the ability to put someonein a space and give them limitedbut meaningful interactionprovides a new experience –one that could shake up thefilm industry.“The thing I find reallyengaging about VR is the sense ofpresence,” says Dave Ranyard ofSony Computer EntertainmentEurope, who is developingsoftware for Sony’s upcomingVR headset, Morpheus. “It feelslike a step change in immersion.”One of the big hits at theSundance film festival in Utah in“The brain accepts virtualfilm as a social interaction,rather than somethingthat’s seen on a screen”January was Wild: The Experience,a 3-minute virtual reality versionof the film Wild starring ReeseWitherspoon, in which viewerscan watch from all directions. VRfirm Oculus has also set up a VRfilm division called Story Studioto produce short films for thelatest version of its headset.But VR film-making doesn’thave to be a blow-out Hollywoodextravaganza to work; evensimple films, like my deckchairexperience, can be surprisinglyconvincing. “In any othermedium this would be boring,you wouldn’t sit there for10 minutes,” says Nick Pittomof VR firm Fire Panda. But it’snarrative experiences where VRwill really shine, he says – if astatic VR scene can be powerful,a story will be even more so.As VR film is a new mediumthere are no set rules. Phil Harperof Alchemy VR, a UK firm working20 | NewScientist | 7 March 2015

For more technology stories, visit newscientist.com/technologyONE PER CENTon immersive natural historyfilms with veteran broadcasterDavid Attenborough, calls hisnature documentaries 360° video,because they are made byarranging a number of camerasin a sphere and stitching theresulting videos together tocreate an all-encompassing film.Watching someone speak to youin VR is more intimate than on aTV screen, he says, because theyappear to be the same size as a realhuman. “The brain begins toaccept this as a social interaction,rather than something that’s seenon a screen,” Harper says.Nowhere to hideBut this approach has itschallenges. Because audiencescan see all around them, it isimpossible to hide equipmentthat would normally sit just outof shot. Even directors have toface their audience, or else hide.“Often I’m just stood in thebackground,” says Harper. “Youcan’t hide anything in 360° video.”In some situations that can freeviewers of a framing camera’sdeception. “360° video is a trulyhonest format,” says Harper,who thinks news broadcasts inparticular could benefit. Earlierthis year Vice News gave the firstVR news report from a protest inNew York.For fictional stories, filmmakersmight want a differentTHE DIRECTOR’S CUTHollywood is embracing virtualreality not just for audiences, butfor directors who want a new viewof the action.An important step when makinga movie is previsualisation, whenfilm-makers create low-cost versionsof the film before spending millionsof dollars on the real thing. Thatused to involve scale models andstoryboards, but now includes3D animations of key sequences.Duncan Burbidge of The ThirdFloor in London, which helpsapproach. One option used byBelgian VFX firm Nozon is torender high-quality 3D worlds ona computer and then “film” insidethem, without having to worryabout having equipment on show.This 360° CGI is convincing –Nozon’s Matthieu Labeau showedme a short but incredibly lifelikeclip in which a robot and a beaverhang out in an ornate ballroom.Both 360° CGI and 360° videohave the same problem, though:they can’t react to the audience.Limited interaction, like selectingdifferent scenes based on whereyou look, is possible, but that’sabout it. Viewers also tend to lookstraight ahead, so you have tocue them to look elsewhere withparticular sounds or pointingcharacters. “I don’t think a moviewhere things are happening allaround you makes sense, becauseyou will feel you missed half themovie,” says Labeau.That’s where game engines, thesoftware that powers gaming’s 3Dworlds, can help. Visual qualitytakes a hit because renderinghappens in real time, but thatalso allows for a more interactiveexperience, heighteningimmersion. You can place a sceneto the left of the viewer andencourage them to turn theirhead, but if they don’t take thehint the characters can movedirectly into view, says Pittom.He recently recreated scenesfrom animated Studio Ghiblifilm-makers with previsualisation,says the film is now experimentingwith adding virtual reality to these3D animations, so directors canexplore a location and plan outtheir shots.“These days sets are becomingincreasingly virtual,” says Burbidge,making it harder for directors to lettheir creative juices flow. Virtualreality changes that, he says. “Theireyes light up like a Christmas tree andthey’re suddenly engaging with it in away that they’re used to.”films in a game engine to letpeople explore them in VR, atechnique that is also findingits feet in the film industry (see“The director’s cut”, below left).But Pittom says the language offilm – close-ups, fast cutting andso on – doesn’t translate well toVR. Instead, in some ways theclosest existing medium is theinteractive theatre pioneered byPunchdrunk, in which there is nostage and the audience directlyinteracts with actors and chooseswhich parts of a scene to watch.But VR can create realistic worldsthat are impossible in theatre. “It’sthe difference between watching akitchen-sink drama and the filmAvatar,” Pittom says.But are consumers ready for anew kind of film that requires newhardware, having so recently been“A cardboard headset thatyou slot your phone intomight be all you need toexperience virtual reality”burned by the 3DTV and film fad?Some VR experiences need verypowerful PCs for the full effect,so the outlay could be enormous.“The demand already existsbut the technology doesn’t,”says Harper. Unlike 3DTVs,which were pushed by televisionmanufacturers, the growth inVR tech is being driven byconsumers, particularly throughcrowdfunding – though that hasled to delays in getting productson shelves. But with the ubiquityand increasing power ofsmartphones, a cheap cardboardheadset that you slot your phoneinto might be all you need to takeyour first steps into VR.Whether as films, games orsomething in between, thereis a lot of confidence that VRexperiences are finally here tostay. Ranyard even thinks thatVR could be a defining part of the2010s, as the Walkman was forthe 80s. “I think people wearinga VR headset and experiencingsomething is going to be aniconic image.” ■Hack your gardenRevolution Bio, a biotech start-upin Fort Collins, Colorado, plans tosell petunias that repeatedlychange colour. Their DNA hasbeen reshuffled to link the genesthat control flower colour to a setthat only switch on during the day.The result is a flower that, forexample, blooms pink in themorning and changes to blueby nightfall.37.9The percentage of the worldpopulation who access the internetat least once a year. Facebook’s TheState of Global Connectivity reportadds that the rate at which the totalnumber of users is growing everyyear has declined, from 14.7 per centin 2010 to 6.6 per cent last year.Smart foodWant to make sure your milk isfresh? Two new London start-upsaim to change the way food ispackaged. Zyme Deal coats theinside of drinks packaging witha polymer to extend shelf life.Fresh Sense’s packagingchanges colour when it sensesthat the food inside has beencontaminated. Both groups arepart of the Imperial Create Labat Imperial College London.REVOLUTION BIOENGINEERING7 March 2015 | NewScientist | 21

TECHNOLOGYFacebook’s exam for machinesMaking your AI take a storybook quiz vastly improves on the Turing test, says Jacob AronJOHN is in the playground.Bob is in the office. Where is John?If you know the answer, you’reeither a human, or softwaretaking its first steps towards fullartificial intelligence. Researchersat Facebook’s AI lab in New Yorksay an exam of simple questionslike this could help in designingmachines that think like people.Computing pioneer AlanTuring famously set his owntest for AI, in which a humantries to sort other humansfrom machines by conversingwith both. However, thisapproach has a downside.“The Turing test requires usto teach the machine skills thatare not actually useful for us,”says Matthew Richardson, anAI researcher at Microsoft. Forexample, to pass the test an AImust learn to lie about its truenature and pretend not to knowfacts a human wouldn’t.These skills are no use toFacebook, which is looking formore sophisticated ways to filteryour news feed. “People havea limited amount of time tospend on Facebook, so we haveto curate that somehow,” saysYann LeCun, Facebook’s directorof AI research. “For that you needto understand content and youneed to understand people.”AI plays 20 questionsIn the longer term, Facebookalso wants to create a digitalassistant that can handle a realdialogue with humans, unlike thescripted conversations possiblewith the likes of Apple’s Siri.Similar goals are drivingAI researchers everywhere todevelop more comprehensiveexams to challenge theirmachines. Facebook itselfhas created 20 tasks, whichQ16/ALAMYget progressively harder – theexample at the top of this articleis of the easiest type. The teamsays any potential AI must passall of them if it is ever to developtrue intelligence (arxiv.org/abs/1502.05698).Each task involves shortdescriptions followed by somequestions, a bit like a readingcomprehension quiz. Harderexamples include figuring outwhether one object could fitinside another, or why a personmight act a certain way. “Wewanted tasks that any humanwho can read can answer,” saysFacebook’s Jason Weston, wholed the research.Having a range of questionschallenges the AI in differentways, meaning systems thathave a single strength fall short.The Facebook team used itsexam to test a number of learningalgorithms, and found that nonemanaged full marks. The bestperformance was by a variant ofa neural network with access toan external memory, an approachthat Google’s AI subsidiaryDeepMind is also investigating.But even this fell down on taskslike counting objects in a questionor spatial reasoning.Richardson has also developed atest of AI reading comprehension,called MCTest. But the questions–Smarter every day–in MCTest are written by hand,whereas Facebook’s areautomatically generated.The details for Facebook’s tasksare plucked from a simulationof a simple world, a little like anold-school text adventure, where“ In the long-term, Facebookwants a digital assistantthat can handle a realdialogue with humans”characters move around and pickup objects. Weston says this is keyto keeping questions fresh forrepeated testing and learning.But such testing has itsproblems, says Peter Clark ofthe Allen Institute for ArtificialIntelligence in Seattle, becausethe AI doesn’t need tounderstand what real-worldobjects the words relate to.“You can substitute a dummyword like ‘foobar’ for ‘cake’and still be able to answer thequestion,” he says. His ownapproach, Aristo, attempts toquiz AI with questions takenfrom school science exams.Whatever the best approach,it’s clear that tech companieslike Facebook and Microsoft arebetting big on human-level AI.Should we be worried? Recentlythe likes of Stephen Hawking,Elon Musk and even Bill Gateshave warned that AI researchersmust tread carefully.LeCun acknowledges people’sfears, but says that the researchis still at an early stage, and isconducted in the open. “Allmachines are still very dumband we are still very much incontrol,” he says. “It’s not likesome company is going to comeout with the solution to AI allof a sudden and we’re going tohave super-intelligent machinesrunning around the internet.” ■22 | NewScientist | 7 March 2015

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APERTURE24 | NewScientist | 7 March 2015

Frozen in dirtTHIS grey kangaroo probably died from starvationat the peak of Australia’s recent 15-year drought,and then quickly became half-buried in thecountry’s iconic red dirt, carried in scorching drywinds blowing across the desert.It was those winds that, in 2009, blanketedAustralia’s east coast in an eerie red cloud -what became known as the East Australian duststorm. When photographer Dean Sewell saw thespectacular storm engulf Sydney, he decided tohead west and investigate its source.He came across this dead kangaroo inTibooburra, one of the places the dust wasfound to originate, about 1200 kilometres northwestof Sydney. “There was no vegetation outthere at all,” says Sewell. “It was as bare as you’veever seen it. And daily there were dust stormsblowing around.”This image forms part of a lifelong project toexamine the region, known as the Murray-Darlingbasin after one of Australia’s most significant riversystems. Sewell says he returns again and againto capture the consequences of climate changeand human activity.The photograph is on display as part of theSyngenta Photography Award 2015: Scarcity–Waste exhibition at Somerset House in Londonfrom 11 March to 10 April. Michael SlezakPhotographerDean Sewell Oculioculi.com.au7 March 2015 | NewScientist | 25

OPINIONSiege mentalityHostility to immigration has deep roots in human psychologythat will be difficult to overcome, says Victoria EssesIN SEPTEMBER 2014, the US faceda crisis. Tens of thousands ofunaccompanied children fromCentral America had crossed theMexican border illegally and werebeing held in detention centres.There were polarised, angrydebates on how to respond.President Obama called the issuea “humanitarian crisis” andworked to house and feed thechildren. Others opposed usingUS resources to care for them.Around the same time, a rowerupted in Europe over migrantships in the Mediterranean. Italysuspended its rescue missionsand the UK refused to supporta new European Union searchand rescue operation, claiming itwould encourage more migrantsto attempt the crossing. Aidagencies and the UN HighCommissioner for Refugeesretorted that such operationswere necessary to save lives.International migration is oneof the major social issues of theday. More people live outsidetheir country of birth than at anyother time in history – 232 millionin 2013 – and this number isexpected to carry on rising.The swell in migration is theresult of many global trends,including growing inequalitiesbetween nations, demand forlabour in countries with a fallingbirth rate and a rise in the numberof refugees and asylum seekers.Opposition to immigrationis widespread in many Westernnations. Anti-immigrationactivists, the media and politicalelites have created a crisismentality in which immigrantsare portrayed as “enemies at thegate”. Immigrants – particularlynon-whites – are blamed for all ofsociety’s woes. Such depictionsencourage support for moreextreme political platforms.Even legal immigrationhas become controversial,with groups such as the UKIndependence Party proposingstricter controls on migrantsfrom certain parts of the EU.Psychologists have much tocontribute to the understandingof what may be driving theseattitudes and behaviours. Yet,with a few exceptions, we havebeen slow to enter the field.We are not starting fromscratch. Attitudes and prejudiceshave been studied for decades,and there are experimentalmethods for probing theirunderlying causes.One especially pertinent areaof research looks at the perceivedrole of competition in intergrouprelations. Psychologists have beendebating this for many years. Inthe context of immigration, itturns out to be very important.As a rule, members of sociallydominant groups tend to believethat their group is superior andhence entitled to resources andprivileges. To maintain their“ More people live outsidetheir country of birth thanat any time and the numberwill carry on rising”dominance, they must fend off“invading” groups who are seenas competing with them for finiteresources including jobs, politicalpower and cultural and religiousinfluence. This can occurirrespective of whether thereare indeed limited resources andactual competition over them.This belief in zero-sumcompetition is central to attitudesabout immigration. There is awidespread belief that any gainsimmigrants make must be at theexpense of members of the hostsociety. This belief is deeplyembedded in Western society,even though it is seldom justified.The upshot of these attitudes ishostility toward immigrants, selfaggrandisement– often in theform of nationalism – andsupport for the exclusion ofimmigrants and refugees.When migrants are allowed tosettle in a new country, they areoften faced with a “damned ifthey do, damned if they don’t”dilemma. If they are economicallysuccessful, they are seen as havingtaken jobs or opportunities awayfrom local people; if they are notsuccessful, they are seen as a drainon the system.Refugees and asylum seekersare especially likely to be treatedwith hostility. Research hasshown that common themesin the media – including claimsthat asylum-seekers are “bogus”and associated with criminals,terrorists and disease – leads todehumanisation. This perceptionallows some in the host nations toassert that refugees deserve theunfair and inhumane treatmentthey receive.26 | NewScientist | 7 March 2015

For more opinion articles, visit newscientist.com/opinionThese reactions ebb and flowdepending on external factorsthat increase uncertainty andanxiety, and challenge the statusquo. Economic recession, naturaldisasters and demands for equalrights for migrants can exacerbateperceptions of zero-sumcompetition and threat fromoutsiders. The Ebola outbreak, forexample, helped to fan the flamesof anti-immigration sentimentagainst Hispanics in the US, eventhough there were no cases ofEbola in Latin American countries.Changing these attitudes is noteasy. We know that just tellingpeople that immigrants are nottaking resources can backfire.This may occur because zero-sumbeliefs are so deeply embeddedand well defended.Change may be easier innations built on immigration ,such as Canada, the US andAustralia. Focusing on theirhistory, on what today’simmigrants have in commonwith yesterday’s, and on thebenefits that immigrants bringcan help forge a common identityand more positive attitudes.However, this will not workin nations, such as the UK, thatdo not see themselves as beingbuilt on immigration. In thesecountries, attempting to describeimmigrants as part of the nationalin-group may simply reinforcenegative attitudes.What is abundantly clear is thatimmigration and asylum-seekingare not going away. Countries thatintegrate immigrants successfullyare less likely to feel the stress andmore likely to reap the benefits.Many have recently come to thisrealisation and are implementingnew policies: President Obama’sTask Force on New Americans isan example. Those countries thatsimply try to slam the door shutare asking for trouble. ■Victoria Esses is professor ofpsychology and director of the Centrefor Research on Migration and EthnicRelations at the University of WesternOntario in London, CanadaONE MINUTE INTERVIEWWhen autism wears a maskMore women have autism spectrum disorders than peoplethink, says Hannah Belcher – we’re just better at hiding itPROFILEHannah Belcher is a PhD student in psychologyat Anglia Ruskin University, UK, who wasdiagnosed with Asperger’s syndrome at age 23.She is conducting an online survey to betterunderstand possible misdiagnoses in femalesWhat led to you being diagnosed so late?I’d had a lot of isolated problems that nobody hadreally pieced together as I was growing up. I wasin therapy when somebody finally said: “I thinkall these difficulties you’ve been having couldactually be autism rather than mental illness.”How did you react to that idea?It was a massive shock. Despite studying autismin my psychology degree, I had never considered Imight have a form of it. That’s also when I realisedthat there is a big issue with diagnosis in general.Did things make sense to you at that point?Definitely. At first I thought: I have friends, Isocialise, it can’t possibly be that. But underneathI’m having the same problems: a lot of anxiety,especially in social situations, and problems likesensory overload. I realised I’m just masking it a lot.So that led to your current research?Yes, I wanted to find out how many otherfemales are out there who are also maskingtheir symptoms and so haven’t been discoveredyet, just because what they are displaying isn’tstereotypical autism spectrum disorder (ASD)behaviour. My research involves a nationwidescreening project and anybody, male or female,can take part at psychscreen.co.uk.How might women be masking symptoms?Females are placed under a lot of pressure to fitin, and I think that drives us to develop copingmechanisms. I read a paper on memory that saidfemale brains are naturally better than male onesat storing up scripts in social situations. When Iwas growing up, I would observe people aroundme, see how they were behaving, and develop ascript to get myself through it. Also, when femaleswith ASD get an obsession it’s not typically withthe same things that males with ASD get into. I’venever been interested in trains or timetables – I’mnot collecting information. I was obsessed withmore normal things.What do you get obsessed with?When I was younger it was music – I would listen tothe same song over and over and drive everyoneup the wall. Now I’m obsessed with psychology.What would an earlier diagnosis have meant?I dropped out of school when I was 14 becauseI couldn’t cope with the pressures. With adiagnosis, that wouldn’t have happened – I wouldhave had the correct support. I think a lot ofundiagnosed females develop other mentalhealth conditions because of the pressure theyare under. Only a fifth of girls with ASD arediagnosed before the age of 11, compared withover half of boys with it, so I think there areprobably more girls with ASD than we realise.Having left school so young, how did youmanage to turn yourself into a researcher?I’m not very good in a group or at understandingpeople, so I found it easier to teach myself. Itaught myself GCSEs, A levels and most of mydegree. It was just second nature to me.Interview by Catherine de Lange7 March 2015 | NewScientist | 27

PROFILEDenise Kandel is aprofessor of sociomedicalsciences at ColumbiaUniversity’s MailmanSchool of Public Healthin New York City. For50 years she hasexplored risk factors fordrug use and addictionSentinel at thegates of addictionThe idea that cigarettes prime the brain for addiction toharder drugs has long been controversial. EpidemiologistDenise Kandel explains how she found hard evidence

OPINION INTERVIEWFor more opinion articles, visit newscientist.com/opinionPhotographed for New Scientist by Mike McGregorIt’s the 40th anniversary of the gateway drugtheory. What led you to propose it?There had been a large increase in the useof marijuana in the 1970s. I was funded todo a project focused solely on marijuana,but I thought that it might also be interestingto look at other drugs, so I slipped somequestions about drinking and smokinginto the interviews.Once I started looking at the data, I realisedthat there were certain ages at which peopletended to get involved in different classesof drugs. They tended to start on cigarettes,alcohol and marijuana at around ages 12 to 14.By doing cross-sectional and longitudinalstudies of drug use, I found the same patternover and over again.What was that pattern?People started with legal drugs such as wine,beer and cigarettes, and some progressed tomarijuana. Then some moved on to cocaine,and then, perhaps, to heroin. Of course, thisdoesn’t mean that just because you smokecigarettes, you are going to become a heroinaddict. But it was – it is – a very compellingpattern. I proposed that cigarettes and alcoholwere gateways to the use of illegal drugs.This created a lot of controversy.You finally put your theory to the test lastyear in a collaboration with your husband,neuroscientist and Nobel laureate Eric Kandel.How did that come about?For years, I’d suggested that a rodent modelwas needed to better understand what mightbe driving this pattern. Then, a decade ago,I was invited to go to a meeting in Pragueorganised by the Society for Research onNicotine and Tobacco, so I asked my husbandif he would like to come. He said yes, and whenI told the organisers, they asked if he wouldgive a basic science lecture. He had done somework on cocaine – nothing to do with thegateway theory – and he talked about that.After his lecture, I said, “You know, Eric,I think we should do something in micelooking at the impact of nicotine on theresponse to cocaine.” That was how it started.If we hadn’t gone to the meeting together, if hehadn’t given that lecture, it might never havehappened.You found a strong neurological basis for thegateway effect. Were you surprised?As I said, I didn’t think that the pattern of usewas random. But testing the idea empiricallyin humans was a challenge. You can’t proposea study where you say, “I am going to presentcigarettes and cocaine, in different orders, toa group of kids to see if they are more or lesslikely to want to snort cocaine after havingtried cigarettes.” But you can do somethingalong those lines in mice.When we did that study – and we lookedat the behaviour, the neurobiology andthe molecular biology – we found a stronggateway effect: when you primed a mousewith nicotine and then exposed it to cocaine,the effects of cocaine were enhanced. We sawmore addiction-like behaviours in those mice,and my husband’s laboratory saw changes atthe molecular level.What sort of brain changes emerged?Just one example is that nicotine enhances theexpression of FosB, a gene involved in reward.Such changes make the brain more receptiveto experiencing the rewards of another drug.“ People aren’t talking abouteffects of e-cigarettes onthe brain, but it’s important”What surprised us was that this effect wascompletely unidirectional: when we did thereverse and primed the mice with cocaineand then introduced them to nicotine, therewas no effect on nicotine at all, either inbehaviour or at the molecular level (NEJM,vol 371, p 932).Were there any other surprises?Yes, another unanticipated finding in ourmouse data was that we only saw the gatewayeffect when exposures were overlapping –when mice were primed with nicotine andthen had at least one day where they wereexposed to both nicotine and cocaine. Thissuggested that people have to be activelysmoking when they start using cocaine forthese brain changes to occur.I went back and re-examined theepidemiological data and found that, in theoverwhelming majority of cases, young peoplewere actively smoking when they startedusing cocaine. And the rate of addiction wastwice as high among those who were smokingwhen they started using cocaine as amongthose who were not smoking at the time.It sounds like a fertile marriage of two verydifferent disciplines…The work exemplifies how you can movefrom epidemiology to the biology lab andback again. The two fields have a lot to offerone another – if scientists are open to it.E-cigarettes and vaping are gaining popularity,touted as “safe” alternatives to smoking.What are your thoughts on this?It is a controversial topic. You need to keep inmind that there are two types of e-cigaretteconsumers: people trying to stop smoking,and young people trying something new.If you’re an established smoker, vapingmight be a safer alternative because you aren’texposed to all the carcinogens that cigarettesproduce. But e-cigarettes are unregulatedand may contain all kinds of compoundsand chemicals that we do not know about.Perhaps most importantly, the currentsafety discussions in the medical communityemphasise the effects of these products on thelungs and heart. People aren’t talking abouteffects on the brain. Our work suggests this isimportant. Nicotine is nicotine, whether froma cigarette or an e-cigarette. And when it getsinto the brain, especially the adolescent brain,there are negative consequences.We are learning that the rates of useof e-cigarettes are growing dramatically,especially among young people. What isdriving that? The science is not keepingup with rapidly changing behaviour.Your initial work on the gateway theory alsosuggested that marijuana is a gateway drug.Over the years, people tended to focus onmarijuana being the gateway drug, thesubstance that would ultimately lead you tococaine or heroin. Indeed, that link does notappear to have weakened over time – but thatwasn’t exactly what I was saying. My researchdescribed a link from tobacco or alcohol tomarijuana, and then from marijuana tococaine. The connection between alcoholand cocaine, and between cigarettes andcocaine, is extremely strong.How might your new work translate intopublic health measures to tackle drug useand addiction?Drug addiction stems from a constellation offactors. We know that genes are important,and so is environment. If you are susceptibleto becoming addicted, then it isn’t safe to useany drugs. We have known for a long time thatyou have to start any intervention early for itto be successful. Our work provides a strongrationale for doing so. If you can get youngpeople to not use tobacco or other substances,if you can educate them about the effects onthe brain, you can reduce the risk – and, withluck, make a difference. ■Interview by Kayt Sukel7 March 2015 | NewScientist | 29

THEY call it “the desert” – a vast,empty landscape separating usfrom a promised land that shimmerslike a mirage on the horizon. A land fullof answers, where we finally achieve acomplete understanding of material reality.Stop dreaming: we can’t get to this nirvana.The way across the desert is too long and hot,and we have no vehicle to take us there. But ifphysicists’ hopes are realised, a machine justwaking from a two-year slumber could bringus a decisive step closer – and might evenreveal answers closer to home.The machine in question is the LargeHadron Collider, or LHC. This most muscularof particle smashers, situated at CERN nearGeneva, Switzerland, garnered fame fordiscovering the Higgs boson in 2012. Thatwas the last uncharted feature of a landscapethat’s now pretty well explored: the landscapeof the standard model, our current best theoryof matter and its workings.Since February 2013, the LHC has beenundergoing a comprehensive overhaul.It's backAfter a two-year makeover,could the rejuvenated LHCspy even wilder particles,asks Matthew ChalmersNow it is gearing up again, more powerfulthan ever before, for a journey towards thedesert – and the complete unknown. Theexcitement is palpable. “We are living in aonce-in-a-lifetime experience, opening thecurtains on a totally new energy scale,” saysJim Olsen of the LHC’s CMS experiment.Particle physicists measure out territoryusing energy as their yardstick. ThroughEinstein’s famous equation E = mc 2 , smashingparticles together at high speed converts theirmass into pinpricks of enormous energythat can in turn form other, more massiveparticles. Our universe started out in a hot,dense big bang, so the higher the energies wereach by ramping up the speed of the collidingparticles, the further back we reach into theorigins of the cosmos and matter itself.In this way the LHC and its predecessorshave allowed us to map out the standardENRICO SACCHETTI30 | NewScientist | 7 March 2015

COVER STORYmodel. This theory describes the fundamentalparticles of matter, known as leptons andquarks, and the particles responsible fortransmitting three of the four forcesoperating on them: electromagnetismand the weak and strong nuclear forces.The crowning glory of this effort wasthe Higgs boson. This particle representsa disturbance in an all-pervasive, invisibleentity, the Higgs field, with which all otherfundamental particles interact to acquiretheir mass. The Higgs is essential to explaina pivotal moment in the early cosmos.Originally, electromagnetism and the weaknuclear force were part of the same unifiedelectroweak force, until the Higgs fieldswitched on around 10 -12 seconds after the bigbang. This “broke the symmetry” of the force,giving the particles that transmitted it differentmasses. Since that point electromagnetism,carried by the massless photon, has had aneffectively infinite range, whereas the weakforce, carried by the meaty W and Z bosons,has been confined to the subatomic scale.Complete yet incompleteThe Higgs’s existence was first predicted in1964, but finding it required the energy of theLHC: 8 teraelectronvolts (TeV) produced inhead-on collisions between protons. Eventhen, theorists were not certain about exactlywhat mass the Higgs should have, assumingit did exist. But it was a no-lose situation: evenif it did turn out to be a mathematical mirage,they would have had the impetus to tear upthe standard model and start afresh.As it was, the elusive particle was foundwith a mass of 125 gigaelectronvolts (GeV),well within the LHC’s energy range. Theoristswere vindicated and two of the Higgs theory’spioneers, François Englert and Peter Higgs,shared the crowning glory of physics, a Nobelprize, in October 2013.But here’s the thing: although the standardmodel is now complete, it is incomplete.The theory includes no description of darkmatter – a sizeable omission, given thatthis stuff apparently makes up 85 per centof all matter in the universe, judging byobservations such as how galaxies move as ifwhirled around by an invisible gravitationalhand. It gives no indication of how a tinyimbalance could have arisen between normalmatter and antimatter to ensure a matterfilledcosmos. It is also mute on gravity,the fourth of the four fundamental forces.More technically, the standard model isdependent on a bevy of arbitrary numbers >7 March 2015 | NewScientist | 31

Unscalable heightsParticle accelerators have conquered many new frontiers – but are still far short of the energies at which the forces of nature become unifiedParticle Accelerator Force unification scaleElectron massFirst particle accelerator: Berkeley 9-inch cyclotron, 1931Proton massFirst proton collider: Intersecting storage ring, CERN, 1971Higgs massELECTROMAGNETISM + WEAKElectroweak unification scaleLHC commissioning energy, 2008LHC upgrade energy, 2015ELECTROMAGNETISM + WEAK + STRONGELECTROMAGNETISM + WEAK + STRONG + GRAVITYGrand unification scale (presumed)Quantum gravity scale (presumed)KeV MeV GeV TeV 10 3 TeV 10 6 TeV 10 9 TeV 10 12 TeV 10 15 TeVto make it work. The Higgs is just oneexample: its mass is one of many quantitiesthe standard model cannot predict, but whichhave to be measured instead. Left to its owndevices, the model does come out with anumber of sorts: it says the Higgs interacts sostrongly with heavy particles that it acquiresa nonsensically large mass of at least 10 13 TeV.For most physicists, the conclusion is thatthe standard model is part of a bigger theory –one that brings us closer to unifying all forcesand understanding matter at all energyscales. The problem is, although precisepredictions vary, our best guess is that furtherbouts of force unification only lie at scalesof trillions of TeV and above, that were lastattained in the first trice of the universe –within 10 -36 seconds of the big bang (seediagram, above).No accelerator on Earth could conceivablyachieve such energies. In this picture,what lies between us and the unattainablepromised land is a desert devoid of interest.It makes the LHC’s upgraded collision energyof 13 TeV seem a rather forlorn gesture.Not so, says theorist Ben Allanach of theUniversity of Cambridge. If the favouritecandidate for a next-generation theory isright, the sliver of new territory we areabout to enter could contain particles andphenomena that will take us a decisivestep closer to an ultimate answer.The theory in question is supersymmetry,or SUSY to its friends. First dreamed up inthe 1970s, SUSY provides the first whiff of a“grand unified theory” that combines theelectroweak and the strong forces. It pullsoff this trick by introducing a forest of“sparticles”, heavier supersymmetricdoppelgängers for each particle alreadyknown, that might appear at scales the LHCcan probe. “If they find signals of a newparticle at the LHC you will see a shock gothrough the theoretical community,” saysAllanach. “We’ll be dancing in the streets.”Not least because the lightest sparticleprovides an excellent candidate for darkmatter. In concert, the sparticles also naturallycancel out troublesome quantum fluctuationsthat cause the Higgs mass to balloon out ofcontrol. A dark-matter-like SUSY particle islikely to slip unseen out of the detectors,leaving a hole when adding up the energy andmomentum produced. But, in general, SUSYparticles are expected to make themselvesknown by the way they decay into lighterstandard model particles in telltale patterns.So beloved of theorists is SUSY, and soearnest is the desire to catch a glimpse of it,that several safeguards must be built intothe analysis procedure to guard against“ No accelerator on Earthcould achieve the energiesneeded to unify the forces”overenthusiasm. Once the crew is confidentthe machine and the analysis are runningsmoothly, the data will be “blinded” –computers doing the analysis will not readout the results of certain calculations untilsufficient data has been accumulated, toprevent standard model processes beingmisinterpreted as something new (see“Faster, higher, stronger”, right).To confirm an anomaly is the result offresh physics, it must be present in datafrom both of the two big LHC experiments,ATLAS and CMS, as was the case for the Higgsdiscovery. “The moment where fluctuationsdeepen and are mutually confirmed ismagical, and it is hard to predict how it willoccur,” says Andreas Hoecker of ATLAS.Or if it will occur at all. In a perfectlysupersymmetric world, sparticles wouldhave identical masses to their partner particlesand would have been seen long ago. Theoristssuppose that, rather like the electroweak force,SUSY is “broken” to make the sparticles muchheavier. Make them too heavy, however, andthey cease to be useful in addressing problemssuch as the Higgs mass, the nature of darkmatter or force unification.The fact that no sparticles were discoveredin the LHC’s first run has already limitedthe breathing space for the simplest, mostaesthetically attractive variants of the theory.Like many theorists, Allanach says the nextfew years of LHC data will decide whether ornot he waves goodbye to SUSY. If nothing’sfound, “it will show that there is somethingreally fundamental at high energy scales thatwe don’t understand,” he says.While physicists keep a keen eye out for asatisfactory solution to the SUSY conundrum,there remains the vexed question of gravity.The conventional view is that there is nochance of seeing even a hint of unificationwith this force at the energy scales the LHCcan probe. Gravity is so much weaker thanthe other three forces – by some 40 orders ofmagnitude – that it can only hope to be unifiedwith them at blistering energies of 10 16 TeVand above, that correspond almost to the heatof the big bang itself.But in 1998 theorists proposed a mindbendingalternative. What if our world existedon a “brane” of three spatial dimensionsfloating in a higher-dimensional space? Thenthe true strength of gravity might be spreadover all these dimensions, leaving it lookingstrangely diluted from our perspective. If so,32 | NewScientist | 7 March 2015

Stargate: the upgraded LHC couldtake us closer to the origins of thecosmos and matterENRICO SACCHETTIFASTER, HIGHER, STRONGERThe souped-up LHC will not interacts with other particlesonly be delivering collisions at such as the top quark and thehigher energy, but will also W and Z bosons, are highdouble their rate, amassing a priorities, says Jim Olsen of CMS.gigabyte of data a second.In the heady daysFurther upgrades are planned, immediately following themeaning that all the data the Higgs discovery, there wereparticle smasher has collected hints that it decayed into pairsso far would represent just of photons at twice the rate1 per cent of the total theexpected in the standard model,machine should collect in its but the discrepancy meltedfull 20-year expedition.away once more of the particlesThe first job after the restart had been produced. Thewill be to see if the LHC’s two big consensus now is that themultipurpose detectors, ATLAS Higgs has a disappointing “plainand CMS, are dealing with this vanilla” flavour, conforminghuge flow of data properly, by to every prediction made of itcalibrating and testing them on by the standard model. Butknown physics. “Rediscovering” perhaps more data will oncethe Higgs boson and making again hint at something moreprecise measurements of its interesting, such as the Higgsproperties, especially how it being not one particle,but a composite bundle.In any case, it is importantto investigate how the familiarlandscape of the standardmodel looks from theperspective of the upgradedmachine. The particle processesin this landscape will formthe expected “background”against which any blips – thesignatures of fresh physics –will manifest themselves.“We need both to confirmthat the standard model stillholds at higher energy, and toprove that we are able to predictand model the main backgroundto new physics searches,” saysOlsen. Only then can the huntfor next-generation theoriessuch as supersymmetry begin(see main story).gravity’s true strength might be such thatthe promised land of unification lies atenergies much closer to where we are now,perhaps even within the LHC’s reach. Then thedesert would be no desert, but full of a host ofstrange objects such as miniature black holes,which the LHC might be able to squeeze intoexistence by warping and pinching space-timein its collisions. These entities would decayinto showers of more familiar particles inhighly distinctive patterns.Even if such things turn out to be tooenergetic for direct observation, thereis a chance that new particles, SUSY orotherwise, might influence the behaviour ofthings at lower energy scales in ways that aremeasurable. Some whispers of unexplainedeffects do lurk in data from the LHC andprevious colliders, and these will grow or fadeas further collisions amass after the restart.If such a blip grew large enough, that in itselfwould be a “huge thing”, says Allanach. But itwouldn’t necessarily tell you what sort of newparticle is at play. The trouble with theoristslike him, he says, is that they will come upwith 20 or more different hypotheses toexplain the same blip – all of which work.For an experimentalist like Hoecker,though, the excitement lies less in provingany “this or that” scenario, but precisely innot knowing what’s to come. “There certainlyis more room for surprise in the vast space ofpossible new physics effects than was the casefor the Higgs discovery,” he says.So the hope is that the territory about tobe explored is a lush forest bristling withparticles that give us clues to the nature of thedesert – and beyond. If not, then we’re stuck,with no indication of what comes next, andno “natural” explanation for why aspects ofthe standard model landscape look as theydo. Faced with such a prospect, physicists areleft postulating that only some spooky finetuning,some strange coincidence of factors,is responsible. Perhaps our standard modelis just one of countless others, in a spacein which all possible universes exist. Orperhaps we can move the goalposts andsay the answers can be found only with amachine that can reach higher energy scales.But in the meantime let’s saddle up for theupgraded LHC ride, wherever it takes us – soas not to be left back staring longingly at aunreachable kingdom, with a bag containingjust the Higgs and a load of unansweredquestions. ■Matthew Chalmers is a freelance writerbased in Bristol, UK7 March 2015 | NewScientist | 33

DA M B U S T E R SAfter a 40 year battle, Brazil’s grandiose plan to tap the hydropower of theAmazon is coming apart at the seams. Sue Branford and Maurício Torres reportABOUT 20 men, their arms painted liketortoise shells, are silently hackingaway at the forest, opening up acorridor about 4 metres wide. Whenthey have finished, the corridor will stretchfor 230 kilometres, encircling the land theycall Sawré Muybu. Every so often the men,indigenous Munduruku, erect a signasserting their ownership of the land intheir own language and in Portuguese.The ancestors of these men used todecapitate their enemies and stick theirheads on poles. Although the Mundurukugave up head-hunting long ago, some of thesigns feature a painting of a head on a pike.This is their none-too-veiled way of telling theBrazilian government they are determined todefend this tract of Amazon forest that hasbeen theirs for hundreds of years.The government has other ideas. If itgets its way, work will soon begin on a hugehydroelectric dam close to Sawré Muybu onthe Tapajós river, one of the major tributariesof the Amazon. Six other large dams are alsoon the drawing board for the Tapajós basin(see map, page 37). If the São Luiz do Tapajósdam goes ahead, parts of Sawré Muybu willbe flooded.Dreams of tapping into the immense powerof the Amazon began in the 1970s, at a timewhen little attention was paid to climate andbiodiversity. The military dictatorship inpower at the time decided to start with a chainof dams on the Xingu river, another mightytributary of the Amazon. However, after alengthy battle with environmentalists andlocal people, it scaled back its plans to a singledam, albeit a huge one.Belo Monte finally got the go-ahead in 2011.When it comes on stream in 2019 it will be thethird-largest hydroelectric dam in the world.The building site is so big that it seems as if anew Panama Canal is being carved out of theforest. Even if one harbours reservations aboutthe wisdom of this massive undertaking, onecan’t help but be impressed by the speed andefficiency with which huge layers of rock areblasted into the air and the rubble carted awayby a phalanx of giant lorries.This scene could eventually be replicatedacross large swathes of the Amazon. Accordingto ecologist Philip Fearnside, a senior researcherat the National Institute for Amazon Researchin Manaus, the government has ambitionsto turn much of the basin into chains ofreservoirs for the production of hydropower.Most of the energy will be used to power bigmineral extraction and refining projects inthe Amazon itself, particularly aluminiumsmelting and gold mining.The issues surrounding the constructionof these dams are painfully familiar: habitatdestruction, loss of biodiversity and heritage,and the trampling of the rights of vulnerableBrazil’s hydropower ambitions arecreating familiar tensions betweendevelopment, biodiversity and therights of indigenous peoplepeople. But the scale on which it could happenadds up to a huge transformation of one of theworld’s most important natural environments.No surrenderBefore they resorted to direct action to defendtheir land, the Munduruku tried to go throughthe proper channels. Brazil is a signatory tothe International Labour Organization’sConvention 169, under which indigenousand tribal people shouldn’t be removed fromtheir land without their free and informedconsent. It also states that before licensing adam, a government must canvass the opinionof all affected groups and only then undertakeviability studies. However, in early 2013 theBrazilian government authorised a researchcompany to send in teams of scientists tocarry out the viability studies, even thoughproper consultations with the Mundurukuhadn’t happened.Incensed, in June 2013 the Munduruku tookthree biologists hostage and paraded them,hands bound, in the square of Jacareacanga,a town beside the Tapajós. The government >CLOCKWORK FROM BOTTOM LUNAE PARRACHO / REUTERS, ULYSSES/WWW.AGEFOTOSTOCK.COM, DADO GALDIERI/BLOOMBERG VIA GETTY, GREENPEACE/JOHN NOVIS34 | NewScientist | 7 March 2015

eacted quickly, promising to carry outthe consultations and the biologists werereleased. However, three weeks later, thegovernment sent the scientists back inunder the protection of 250 policemen –still without any proper consultation.According to reports from the Mundurukuand other local people, the police created anatmosphere of intimidation and terror byentering villages unannounced, sometimesarriving by helicopter. In a surreal episodewhich recalled the days of the dictatorship,a policeman bearing a machine gun triedto bar our way as we approached a groupof biologists in a roadside cafe in a remotearea of the Tapajós valley.Brazil’s constitution also appears to beon the Munduruku’s side, as it bans thepermanent removal of indigenous peoplefrom their land. But the land claim has to berecognised by the authorities, which can onlyhappen after a report giving the coordinatesis officially published by FUNAI, the NationalIndian Foundation.FUNAI began mapping Sawré Muybu eightyears ago and completed the job in September2013, but has yet to publish its report. Untilthat happens, the territory isn’t formallyrecognised as belonging to the Munduruku.The Munduruku believe that the governmentis deliberately dragging its heels.We obtained a leaked copy of the report,which shows that FUNAI accepts theMunduruku’s claim to the land. TheMunduruku are using its coordinates tomark out the boundary of their territory.But it is a long and laborious process.The Munduruku’s troubles have createda dilemma for the scientists carrying outthe viability studies, for whom it hasbecome embarrassingly clear that theyare involved not in impartial research butin a fait accompli. Talking off the record,some are distraught at the prospect of theoverwhelming losses that will be borne bypeople and ecosystems if the dam goes ahead.Yet they are reluctant to protest or resign,fearing that they will be blacklisted by thegovernment and their career prospectsharmed. So they dutifully produce theirreports hoping to get the government torethink its policies. But the governmentsimply cherry-picks the evidence.A more vigorous response has comefrom archaeologists. Evidence is beingunearthed that the Tapajós basin wasoccupied by indigenous people forthousands of years before the Portuguesearrived, and archaeologists have beenClockwise from top left: the BeloMonte dam; pristine rainforest;deforestation; Munduruku protestscontracted to carry out environmentalimpact studies. This has caused widespreadunease. At their meeting in August 2014,the northern branch of the BrazilianArchaeological Society passed a motionstating: “We are gravely concerned by theinvolvement of archaeologists in a processthat relies on the presence of the NationalSecurity Force to guarantee the fulfilmentof the research. For this reason we are callingon our professional colleagues not to takepart in activities related to the environmentallicensing of the dams along the Tapajós river.”The concern at the biodiversity loss and thethreat to indigenous people is exacerbated bya growing awareness that the drive to harnessthe power of the rivers may, in the long term,be futile. São Paulo, the industrial heartlandof Brazil, is in the grip of the worst drought inliving memory. The clouds from the Amazonthat make the basin itself so wet and alsodeliver rain to the south of the country –dubbed “flying rivers” by one Brazilianscientist – have failed to materialise.While this may be a result of natural climatevariability, Antonio Nobre, a senior researcherat Brazil’s National Institute for SpaceResearch in São José dos Campos, says thatthe disruption is linked to deforestation.Recent research has shown that Amazonvegetation, particularly large trees, play acentral role in maintaining the hydrologicalcycle. “In a single day a large tree in therainforest can pump over 1000 litres ofmoisture from the soil into the atmosphere.If this is scaled up for the whole forest, itmeans the Amazon forest transpires 20 billiontonnes of water a day,” he says. Cut down theforest and you destroy the flying rivers.According to official satellite data, 22 percent of the forest has been felled. But this isan underestimate as it fails to account forselective logging, which the satellite imagesdon’t detect. After several years of markeddeclines in forest clearance, which wonBrazil international plaudits, the level ofdeforestation has risen again.It seems probable that continued forestdestruction will sooner or later trigger aCLOCKWISE FROM BOTTOM LEFT LUNAE PARRACHO / REUTERS, DADO GALDIERI/BLOOMBERG VIA GETTY IMAGES, FAUSTO GIACCONE / EYEVINE, DANIEL BELTRA/ GREENPEACE36 | NewScientist | 7 March 2015

Watery graveThe Brazilian government wants to build seven large hydroelectric power stations on the Tapajós riverand its tributary, the Jamanxim, flooding parts of the indigenous Munduruku’s territory50 kmAMAZONPlanned dams1234TAPAJÓS BASINManausTAPAJÓS RIVER3São Luiz do TapajósJatobáChacorãoCachoeira do CaíJacareacangaBELO MONTEDAM SCHEMEXINGUBRAZILGenerationcapacity8040 MW2338 MW3336 MW802 MWTAPAJÓS RIVERFloodedarea729 km 2646 km 2616 km 2420 km 2dramatic transformation of the Amazon.The tipping point was spelled out in 2013by the Brazilian Panel on Climate Change:“Modelling studies have suggested that, ifdeforestation reaches 40 per cent in theregion, drastic changes will likely occur inthe hydrological cycle, with a 40 per centreduction in rainfall during the monthsfrom July to November.”Even scientists with a less alarmist outlookthan Nobre believe that, if deforestationcontinues, the viability of the large damsmay be compromised. Until recently mostscientists thought that cutting down treesnear dams increased the amount of waterflowing into them. But a recent study by theAmazon Environmental Research Institutein San Francisco, California, came to a verydifferent conclusion. It found that by 2050,when on present trends at least 40 per centof Brazil’s Amazon forest will be gone, therewill be a significant decline in river flows andenergy generation (PNAS, vol 110, p 9601). Thiswould make the reliability of the dams as anenergy source highly questionable.Another difficulty is that big developmentprojects always provoke an unruly influx of567Sawré Muybu(Mundurukuterritory)24JamanximCachoeira dos PatosJardim de Ouro1ItaitubaSawré MuybuvillageJAMANXIM RIVER881 MW528 MW227 MWillegal loggers, land thieves, cattle ranchersand slash-and-burn farmers, who exacerbatethe deforestation. The government promisesit will be different with São Luiz do Tapajós,through the use of river platforms similar toNorth Sea oil rigs to make it possible to bringpeople in using helicopters rather than roads.But Juan Doblas of the non-profit Social-Environmental Institute in Altamira pointsout a flaw: “Yes, when a dam is up andrunning, you can bring workers in byhelicopter. But the main environmentaldamage is done during the building of thedam, when thousands of labourers are needed.You can’t bring in this volume by helicopter.Big projects always cause forest felling andthere is no sign of that ending.”A radical solution would be to see if Brazilcould do without dams on the Amazon. Nobresays that much could be done to save energy.“Brazil wastes 55 per cent of public street5674 km 2117 km 2426 km 2“ Big projects always causeforest felling and there isno sign of that ending”7lighting because the lenses spread the beamwider than is necessary. By refocusing thelight we would save as much energy as BeloMonte will generate,” he says. Another sourceof waste is electric showers. “If we were toinstall solar water heaters, which would notbe difficult with the amount of sunshine weget, there would be no need for furtherhydroelectric dams in the Amazon.”Along with growing doubts from scientists,another factor is creating the perceptionthat the authorities’ love affair with Amazonhydropower may be waning. Historically,one of the biggest drivers of dam-buildinghas been a cosy relationship between bigengineering companies and their politicalallies. “Energy planning in Brazil is not treatedas a strategic issue but as a source of moneyfor engineering companies and politicians,”says Felício Pontes, prosecutor for the FederalPublic Ministry in Pará.But many of the companies are now caughtup in a massive corruption scandal involvingbribery and money laundering by the stateownedoil company, Petrobrás. Investigatorsare examining the contracts for the BeloMonte dam, and a leading executive of oneof the companies, Camargo Corrêa, whichhas been funding viability studies for theSão Luís do Tapajós dam, has been arrested.As a result, there is no longer the sameimpetus to push ahead with the dams. Untilrecently, the government was planning togenerate electricity from all the maintributaries of the Amazon east of the city ofManaus. But in a leaked copy of its latest 10-year energy plan, obtained by the O Estado deS. Paulo newspaper, all dams except São Luizdo Tapajós have been removed. Even this is nolonger on the list of priority projects to be builtover the next five years. If confirmed, thisamounts to a major rethink of Brazil’s energyplans, and a possible reprieve for the Amazon.Meanwhile, the Munduruku fight on.Emboldened by a judicial decision that “full,free and prior consultations” must be carriedout, a delegation of 30 made the five-day busjourney to Brasilia at the end of January topresent their demands – the central one beingthe cancellation of the dam.They are still a long way from achievingvictory. But after decades of bitter struggle,the battle for the Amazon finally seems to begoing their way. ■Sue Branford is a freelance journalist specialisingin Latin America. Maurício Torres is collaborativelecturer in the postgraduate programme at theFederal University of Western Pará, Brazil7 March 2015 | NewScientist | 37

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Your brainon migraineMigraines cause profound changes to the way people experiencethe world every day. Helen Phillips reports“ WELL a very, very heavy ah heavy duitburtation tonight. We had a veryderes dereson. But let’s go aheadtarish tasen losh lobitt behend dupet”. Newsreporter Serene Branson’s unintelligible liveTV commentary on the 53rd Grammy awardsceremony in 2011 made her an overnightinternet sensation. As the paramedicsattended, the worry was that she’d suffereda stroke live on air. Less-kind pundits blameddrugs, stage fright, or alcohol. In interviewsshortly after, she revealed she’d been havinga migraine.I too have experienced this type of migraine“aura”, though thankfully rather less publicly.In mid-sentence, with absolutely no warning,I began talking drivel. I couldn’t find the rightwords, but I also couldn’t stop myself garblingnonsensical phrases with similar startingsounds or patterns to the words I sought. I wasmortified. A few minutes later I developed aCHRISTINA Ksteadily expanding blind spot edged with asemicircle of dancing black-and-white zigzags.Several days later came the most intenseheadache imaginable. I was 19.Migraine is often thought of as anoccasional severe headache, sometimesaccompanied by strange visual effects andnausea. There’s a feeling it isn’t really seriousbecause once the headache is over the persongoes back to normal. But these bizarre anddisturbing aura symptoms alone should tellus there’s far more to migraine than meets theeye. Over the past decade, research has beenbuilding a picture of a condition which ismuch more serious than many give it creditfor. It shows that migraine is caused by realstructural and functional differences in thebrain, and that people who experiencemigraines feel, see, touch, hear and respondto the world differently all the time, not justduring an attack. Perhaps more worrying,the disorder, and the brain changes thataccompany it, seem to be progressive, gettingworse with each attack. “Migraine is a moreserious condition than people have thought,”says David Borsook of Harvard Medical Schoolin Boston. “These repetitive strikes changebrain networks, and we are just beginningto understand those.”More than 37 million people in the USalone experience migraine, although anestimated 50 per cent of sufferers, alsoknown as migraineurs, go undiagnosed.Given these recent findings then, it’s time torethink how we tackle, diagnose and treat thecondition. “We need to stop calling migrainea vascular disease or a pain condition,” saysmigraine expert Peter Goadsby, who splitshis time between King’s College London andthe University of California, San Francisco.“It is a neurological disorder.”The effects of migraine have been >7 March 2015 | NewScientist | 39

ALEX COGHE/PLAINPICTUREIF YOU GET THEM…Although migraine is a result of abnormal brainactivity, the causes are still unclear. Around70 per cent of people who report migraines havea family history of the condition, but because ofmisdiagnosis, family history may remain hidden.Migraine attacks usually involve intense,one-sided throbbing head pain. They are alsogenerally accompanied by other symptoms,ranging from nausea and sickness to sensitivityto light, sounds and smells. There may be nasalcongestion, tears and sweating. Sometimesthere is tingling in limbs, neck pain, evenone-sided paralysis and slurred speech, sooccasionally it looks almost like a stroke. Andaround 20 per cent of people who suffer frommigraines get the strange visual or auditoryhallucinations known as aura. Because thesymptoms of migraine are so broad, it isoften misunderstood and misdiagnosed.So if you think you might suffer frommigraine, seek professional advice and get aproper diagnosis. Find out what kind of lifestylechanges and medications are most appropriatefor your symptoms. Do not just tough it out,as that can make things worse in the longrun. Self-medication with over-the-counterpainkillers can even prolong the pain. Takingpainkillers can lead to rebound, where thesymptoms return as the drugs wear off, leadingto a cycle of often worsening symptoms.Do try to keep a good routine, sleep well, stayhydrated and try to eat “clean”. If nothing else itmight help you to identify patterns and triggersfor your attacks. A migraine diary will help, andthere are also online diaries and apps which canhelp find links you might not have considered.The brain attends to all sorts ofthings it should be ignoringdocumented for centuries, but only now arebrain imaging technologies allowing us to seethe big picture. Most media attention so farhas focused on reports that MRI brain scansof some people with migraine show tinyareas of damage, which show up as smallbright spots on the image. In 2004, Mark Kruitfrom Leiden University Medical Center in theNetherlands and his colleagues scanned thebrains of around 300 people with migraineand found that they were more likely to havesuch bright spots than carefully matchedcontrols. Some of the spots, mostly in thecerebellum, related to changes in the deepwhite matter, which is the insulating sheaththat allows nerve fibres to send electricalsignals efficiently and is now also knownto be important in learning and memory.Worryingly, other spots closely resembledthe kinds of damage you would expect to seein the brain of someone who’d had a stroke.The incidence of these so-called stroke-likelesions was not high, but it was statisticallysignificant – they were apparent in around8 per cent of cases of migraine with auracompared with 5 per cent of controls.Stroke-like damageAs if the words “stroke-like lesions” weren’tworrying enough, no one is quite sure whatthese spots of damage on the brain are, orwhat they mean. We already know thathaving migraines puts people at greaterrisk of stroke – especially those with auraand cardiovascular risk factors such as bloodpressure problems, who smoke or are obese,and women taking certain oral contraceptives.“Because the blood flow to parts of the brainrelated to the aura first increases thendecreases, it is possible that the changes arerelated to small strokes,” says Richard Liptonof the Albert Einstein College of Medicine inNew York, who recently published a detailedreview of structural brain changes inmigraine. But as both he and Kruit’s team arequick to point out, the spots don’t appear tocause symptoms, or make migraine worse.To find out what’s really going on, thesechanges needed to be monitored. Do regularmigraines cause more areas of stroke-likedamage? And to what effect? Kruit and histeam rescanned most of their volunteersnine years later. Interestingly they found thenumber of spots had slightly increased overtime in women with migraine, but not inmen, but they didn’t correlate with migrainefrequency, severity, or treatment. Neitherdid the spots seem to have any bearing oncognitive functions like memory or attention.Another long-term study in France found nolink between migraines and cognitive decline,all the way to age 80.That is good news given that even silentstrokes – where damage to the brain can beseen on scans without there being any clinicalsymptoms – have been shown to be a risk factorfor cognitive decline and dementia later on.According to Kruit, the spots may relate tohaving the “disease” of migraine, rather thanbeing caused by successive attacks. And it“ Even normal touch canfeel painful to people whohave frequent migraines”doesn’t look like the brains of people withmigraine age faster, says Lipton.So the jury is still out on the significance ofthe stroke-like lesions in migraine. However,there are other, less-talked-about structuralchanges in the brain which may be much moreimportant. These differences relate directlyto the changing and increasing severity ofmigraine symptoms over time. Several groupshave now described changes in the thicknessor volume of various brain areas in peoplewith migraine, and they seem to underlie thesensory, emotional and sex differences inpeople’s experience of the condition.In one study from 2007, NouchineHadjikhani and her team at Harvard MedicalSchool found thickening of a region known asthe somatosensory cortex, which maps our40 | NewScientist | 7 March 2015

Cycle of sensitivityThe brains of people who experience migraine work differently overall, not just during an attack.Studies are starting to reveal which circuits may play a role in the various stages of migraine,although the picture is still developingCortexSomatosensory cortexVisual cortexThalamusHippocampusInsulaHypothalamusPostdromeMigraine “hangover”.During attack, blood flowfirst increases thendecreases, which results inexhaustion and hungerPainOveractive sensory andemotional circuits giveoverwhelming feeling of pain,plus heightened sensitivityto light and soundInterictal phaseBetween attacks, the brain showsdifferences in structure andfunction. Senses, attention, painand emotions affected.Oversensitivity to changes insleeping or eating patterns,hormones, etcProdromal orpromonitory periodThe already oversensitive brainis thrown out of balance byenvironmental or behaviouraltriggers. Common effectsinclude sensitivity to light,sound and touch, as well asnausea and stressAuraOverexcitable circuits lead tocortical spreading depression – astorm of neural activity thatcrosses the brain. Symptoms caninclude hallucinations andspeech irregularitiesTRIGGER TROUBLEOne unique feature of migraine is the wayit appears to be “triggered” by somethingenvironmental. Common triggers are said toinclude red wine, chocolate, flashing lights,hormonal changes, sleep disruption, and stress.Doctors advise patients to try to identify theirown triggers by keeping a migraine diary, andto make changes to their lifestyle and diet.But recent studies show that the story ismore complex than first thought.For a start, the things that get reported astriggers may not always be to blame. In onerecent study on people who believed theirmigraines were triggered by flashing lights,the researchers failed to trigger a single attackin the lab using all manner of annoying lightingand strobes. Instead, it could be that the triggeritself does not cause the attack, but that peopleare more susceptible to these stimuli once amigraine is under way, and are therefore morelikely to notice them.During the prodome stage of an attack(see diagram, left) people are more sensitive tostimuli such as light and noise, but don’t alwaysrealise that their attack has started. It’s possiblethat sleep may be disrupted by the attack, thatthings feel more stressful or that a stimuluslike bright lighting becomes more troublesome.These things might then be blamed for theattack that was already in progress.Stress let-down, the feeling of relief aftera period of stress, has also been found to beone of the most common triggers. Peopleoften report migraine at the weekend or aftera big exam or work event. But even this mightactually be due to change of routine – a lie-in,say, or a change in diet or caffeine intake.sense of touch in different parts of the body.They found the most significant changes inthe region that relates to the head and face.“Migraine has always been considered as anepisodic problem,” says Hadjikhani. “But ifyou have a series of episodes of pain in the facearea, it increases cortical thickness.” If peoplehave frequent migraines, they often develop acondition called allodynia, where even normaltouch can feel painful. Estimates vary, but thiscondition is thought to affect at least a quarterof migraineurs. “It’s an important finding,”she says. “Migraine could have long-termconsequences.”Her group has also identified thickening inthe visual cortex, which makes sense whenyou consider how frequently migraine attacksare accompanied by visual disturbances. Oneof the physiological features of a migraineattack is a storm of neural activity calledcortical spreading depression that passesin a wave across the brain’s surface.Hadjikhani’s group was first to record thisepilepsy-like activity in a brain scanner duringmigraine aura, in a visual region that respondsto flickering motion. The study confirmeda long-suspected link between spreadingdepression and the aura that often precedesmigraine pain. “People with migraine oftenhave a history of motion sickness, sensitivityto stripes or certain visual stimuli,” saysHadjikhani. “And we found increasedcortical thickness in these visual areas.”She admits they don’t yet know whetherthe changes cause the areas to produce thesestorm waves or are a result of them. Indeedother work suggests that spreading depressionmay occur all over the brain, often unnoticed,and may even happen in healthy brains.So aura may be the result of a person’s brainbeing more sensitive to spreading depression.The list of structural changes, often in theform of thickening, has been growing in recentyears, so that now there is barely a region ofthe migraine brain that has been found to beunchanged. This list includes sensory andemotion areas, and the hippocampus – whichis involved in autobiographical memory andnavigation – along with reward networks,frontal areas involved in planning, cognitionand voluntary actions and, not surprisingly,regions that involve pain. “We have to lookat [the possibility] that the whole brainis altered,” says Borsook, with different >7 March 2015 | NewScientist | 41

RELIEF AHEADAs we learn more about theunderlying neural mechanismsof migraine, new treatmentsare emerging. Brain stimulationwill be huge in the next fiveyears, says Peter Goadsby ofKing’s College London.Transcranial magneticstimulation (TMS) and othertechniques that deliver smallelectrical currents throughelectrodes on the forehead arealready proving effective insome cases of migraine, as wellas for chronic pain conditionsand depression.These treatments seemto work by steadily alteringand normalising oversensitivebrain circuits, though atpresent it’s not clear how.One big advantage is that theyare well tolerated comparedwith other therapies, includingdrugs and botox – which isapproved for migrainetreatment by the US Foodand Drug Administration.TMS and the like also havescope to treat people who havebecome insensitive to migrainedrugs, those who experiencerebound symptoms (see “If youget them…”, page 40), andwomen who are pregnant orbreastfeeding.A huge change in drugtreatment is on the horizon too.The first group of medicines tobe developed specificallyfor treating migraine is just afew years from the pharmacy.These block a molecule calledcalcitonin gene-relatedpeptide, or CGRP. Goadsbyfirst found CGRP in the blood ofpeople experiencing a migraineattack nearly 30 years ago.Now, a handful of drugs thatinterrupt CGRP receptors arebeing tested for episodicmigraine, and monoclonalantibodies, which bind to thereceptors for longer, are beingtested for people with chronicmigraine. Several candidatedrugs are in phase II trials.These could be ideal fortackling the long-term effectsof migraine on the brain.structures being more or less involved. “Thewhole migraine brain is very excitable,” headds, “much more excitable than in healthysubjects.” His suspicion is that repeatedattacks make it that way. Indeed, Hadjikhani’steam also found microscopic structuraldifferences in the thalamus, an area thattransmits sensory information to the cortexand controls its excitability. “It was as thoughsmall pathways had become highways totransmit the pain, says Hadjikhani. “Usingthe system repetitively makes it work moreefficiently.”But it is perhaps functional changes inthe hypothalamus that have caused mostexcitement in the medical world. Thehypothalamus is vital for controlling internalbody states – things such as sleep and wakingcycles, metabolic balance, feeding behaviour,stress, and hormone cycles – all of which arelinked to migraine attacks. Migraineurs willrecognise many of the symptoms controlledby circuits around the hypothalamus: nauseaand vomiting, nasal congestion, wateringeyes, excessive urination, thirst and hunger,cravings, yawning and tiredness. “The ideathat the hypothalamus is a critical centrein migraine is not new,” says Borsook, “butwe now know that there are functionaldifferences in how the hypothalamusinteracts with other brain areas in migraine.”Functional MRI scans enable researchersto look at how closely correlated the activityof different brain areas is. In people whoget migraines, such scans revealed raised“functional connectivity” in the circuitsbetween the hypothalamus and areas thatcontrol automatic regulation of our bodystates. These areas normally respond to allsorts of stressors including cold, hungerand exercise. This makes the circuitsmuch more sensitive. Think of the levelof sensitivity as a threshold. If you haven’tslept well or eaten properly, your oversensitivityto dysfunctional activation“ A startling possibility isthat infant colic is anearly form of migraine”allows your brain to overreact, and go intoa full-blown migraine attack. What’s more,says Borsook, this sensitivity seems toincrease during an attack, and with moresevere or more frequent migraines.A better grasp of these structural andfunctional changes may also be the key tounderstanding one of the most curiousaspects of migraine – that it affects aroundthree times as many women as men. NasimMaleki, also at Harvard Medical School, andcolleagues including Borsook, found that thebiggest differences between male and femalemigraineurs were in two brain regions. Onewas the precuneus, an area that is likelyinvolved in self-awareness, which fits with myown experience of migraine – I always describethe pain as coming from the part of my brainwhere I feel “I” am when I close my eyes.The other is the insula, specifically theposterior insula, which is involved in sensoryprocessing and control of our automatic bodyfunctions. The insula is an intriguing part ofthe emotional brain, involved in severalimportant functions including sensation,autonomic regulation, understanding ourinternal state (interoception), and “salience”,in other words judging what is important rightnow. Both areas were thicker in women withmigraine than in men with the condition.When it comes to functional imaging ofmale and female brains, Maleki’s team foundthat migraine in women seems to involvemore activity in emotion circuits than in men.The pain may be a more emotional experiencefor women, and anecdotally many do reportfeeling intense mood swings before andafter migraine strikes. There is also a strongassociation between depression and migraine.Female sex hormones may well underlie thedifferences, somehow making the circuitsmore sensitive to change with repeatedattacks, but the mechanism is not clear.Borsook is now studying how migraineprogresses in children as they enter andpass through puberty, and has found starkdifferences between boys and girls. “There’s42 | NewScientist | 7 March 2015

diminish over time. Suspecting thatthe problem was related to attention,Mickleborough recently tested visualattention in migraineurs. “They seem to beattending to things they should be ignoring,”she says: “They find it hard to concentrate.”It matches anecdotal reports and my ownexperience that especially in the day ortwo before an attack, I find myself easilydistractable and unable to settle at mycomputer. I can’t tolerate flickering adverts,or ignore TV screens and am much moredistracted by music or talking.no question that when boys go throughpuberty there’s a good chance their headacheswill resolve,” he says, “and in girls, a goodchance their headaches will get worse.”Work with children is adding weight tothe idea that migraine is a progressive braindisease, which may appear in different waysat different stages of life, beginning withsome kind of genetic susceptibility. Onestartling suggestion is that infant colic, theuncontrolled crying and fussiness oftenblamed on sensitive stomachs or reflux, maybe an early form of migraine. Goadsby andcolleagues have looked at the prevalence ofmigraine in mothers of babies with colic, andearly indications are that it is more prevalentin the family of colicky babies. In a study of154 mothers whose babies were having aroutine two-month check-up, the migrainesufferers were 2.6 times as likely to have ababy with colic. It is possible that a baby witha tendency to migraine may not cope wellwith the barrage of sensory informationthey experience as their nervous systemstarts to mature, says Goadsby, and thedistress response could be what we call colic.So what are we to make of all this research?The brain of a person with migraine isemerging as oversensitive, and increasinglyso with successive attacks. Perhaps notsurprisingly, researchers are findingcorresponding differences in brain function,even between attacks. Marla Mickleborough,a vision specialist at the University ofSaskatchewan in Saskatoon, Canada, foundheightened sensitivity to visual stimuli in thesupposedly “normal” period between attacks.People with migraine are less able to toleratestaring at a bare light bulb, for example.Her findings draw on previous workshowing that the brain’s response doesn’t“habituate” as it would normally do. Usuallythe brain comes to see something repeatingover and over again as unimportant, but inpeople with migraine the response doesn’tTYPES OF MIGRAINEMigraine with aura Warning signs before themigraine begins, such as visual distortionsMigraine without aura Migraine occurswithout warning signsSilent migraine Aura or other migrainesymptoms are experienced, but no headacheChronic migraine Experienced at least 15 daysin every monthEpisodic migraine Occurs occasionallyAbdominal migraine Usually occurs in children.Recurring attacks of abdominal painMenstrual migraine A specific condition wherethe attacks occur around menstruation and at noother timeHemiplegic migraine Attacks include paralysisor weakness on one side of the bodyHard to ignoreMickleborough also finds that migraineursdo not perform well in tests of negativity bias –a well-studied psychological phenomenon inwhich we pay more attention to stimuli wedon’t like, perhaps because they have a higherchance of being important and threatening.The fact that migraineurs don’t do this couldadd to the general feeling of being distractedby numerous stimuli all at once and finding itharder to focus on the right thing.The idea that our brains are different,and growing ever more so with every attack,is deeply worrying for those of us whoexperience migraine. It’s a wake-up callfor doctors to treat the condition moreaggressively, and to find out more about eachindividual’s particular triggers (see “Triggertrouble”, page 41) so as to stop attacks fromhappening, rather than let people sufferthrough each one while it sensitises the brain.But there is a silver lining. Despite talkingabout migraine as a progressive neurologicaldisorder, these structural changes should notbe likened to dementia, Alzheimer’s disease orageing, where brain tissue is lost or damagedirreparably. “That’s the wrong way to look atit,” says Borsook. In migraine, the brain iscompensating, he says. “Even if there’s agenetic predisposition, it is the disease itselfthat is driving networks to an altered state.”That means that treatments that reducethe frequency or severity of migraine willprobably reverse some of the structuralchanges too. Lipton agrees.“Headache begets headache,” he says.Treatment used to be about reducing theimmediate pain, he says, but now it seemsthat finding good treatments for migrainesmay have much longer-term benefits. ■Helen Phillips is a consultant for New Scientist andauthor of Emotion: Pleasure and pain in the brain(OUP, 2014)7 March 2015 | NewScientist | 43

An unexpected discovery has created a laser that canmanipulate your vision. And you won’t even know you’rethe target. David Hambling reportsBlinded bythe heatIT BEGINS without warning. You are drivingfast on the highway and your vision starts toblur. As vehicles around you become hazyand the road ahead fades, you lose control.Even if you survive the impending crash, noone may ever find the cause, because you havebeen targeted by a weapon that leaves no trace.Such a device already exists. Tagged byits developers as non-lethal, it is a laserdesigned for use by security services or onthe battlefield. It sends out an invisible beamthat temporarily blurs vision, apparentlywithout damaging the eye. The hope is that itcould be used to temporarily blind potentialsnipers or disable terrorists before they act.But the story is not quite so clear-cut.Would such a laser be less dangerous thanconventional alternatives, such as laserdazzlers or tasers? After all, with a driver orpilot in the firing line, it could cause fatalities.What’s more, there would be no evidence ofthe cause. Aviation authorities are alreadytrying to prevent people from shiningpowerful laser pointers at aircraft, fearingthey will blind pilots. Such pointers producevisible light, so at least there is a chance ofdeterring or catching the culprits. But it isa different story with this weapon. In thewrong hands, it would cause chaos.Lasers concentrate energy into intenselight beams, so it is hardly surprising thatpeople have tried to turn them into weapons.In the 1980s, for example, the UK Royal Navydeveloped a system to blind attacking pilots,and the US created lasers to defend aircraft,helicopters and vehicles. Laser weaponscapable of blinding people were outlawed byan amendment to the Geneva Conventionsin 1996, after a successful campaign.Yet lasers that cause temporary vision lossare still permitted. Laser dazzlers or “oculardisrupters” used to send signals or as dazzlersGIPHOTOSTOCK/SPLare widely used. The Glare system, forexample, is a flashlight-sized device that wasfielded by the US military in Iraq to signal todrivers as they approached checkpoints. Andthe US police and coastguard service receivedthe go-ahead to use laser dazzlers in 2012.Although designed to be safe, these devicescan still damage eyes, particularly when usedat close range. To help prevent this, dazzlershave a minimum safe distance at which theyshould be operated – and some even switchoff automatically when a target is too close.Despite this, lasers damaged the eyes of someUS soldiers in Iraq. It is not clear how manycivilians have been affected.So if lasers are going to be used in theseways, there’s a need to make improvements.Researchers have tested strobing lights, andcombinations of light and sound that candisorientate, even at low light intensities. Thenin 2009, researchers from defence technologycompany Northrop Grumman and the AirForce Research Laboratory at Brooks City Basein Texas came across a promising lead: theynoted that mammal eyes are particularlyresistant to damage by infrared laser light ata wavelength of 1320 nanometres. In tests ittook at least 50 times more power at thiswavelength to damage the retina than atshorter wavelengths.Further studies revealed why: althoughour eyes can’t detect light at around1300 nanometres, the infrared is absorbedby the structures of the eye – the lens, corneaand the fluid inside the eyeball – and they heatup. This changes the eye’s refractive index,altering the way light travels through it. Theeffect, known as thermal lensing, prevents theeye focusing the light onto the retina, so thereis no tight pinpoint of light to cause damage.Thermal lensing seems to open the door toall kinds of remarkable effects. In tests with44 | NewScientist | 7 March 2015

TODD DARLING/POLARIS/EYEVINElow-power infrared beams, the air force team,working with researchers at the Universityof Texas at Austin, found they could blurthe eyesight of volunteers, making it appearthat they were gazing through a heat haze. Inanother study, published in 2014, the teamreported reducing the eye’s ability to focus by2 dioptres, equivalent to inducing moderateshort-sightedness. With more powerfulbeams, they found they could entirely blockout parts of their volunteers’ vision. All theseeffects disappeared as soon as the laser wasturned off and didn’t heat the eye enough tocause damage, says Benjamin Rockwell, oneof the team at the Air Force Research Lab. Withmuch the same range as a conventional laser,it seems to offer a less-dangerous alternativeto visible-light dazzlers, he says: “a unique wayto temporarily challenge someone’s vision”.Any device that manipulates eyesight couldmake a powerful weapon. It could certainlystop a sniper, or disable a driver approachinga checkpoint. But there are still possibleproblems, says Jürgen Altmann, a physicistat the Technical University of Dortmund inGermany. “Whenever one manipulates thehuman eye, there are obvious safety issues,”he says. We don’t fully understand thermallensing yet, he says, so more research isneeded on the effect and its implications.There is a big difference between controlledtests in a lab and the much broader beamsused during actual operations, he says.Stephen Coleman from the Universityof New South Wales in Canberra, Australia,who studies military ethics, warns that usingany kind of invisible light is inherently moredangerous: “With visible dazzlers, exposureis limited because people look away.”Visible lasers have been aimed at thepolice during riots and public protestsOne in the eyeLaser pen attacks on the eyes of pilots during flightshave risen dramatically over recent years in manycountries including the US and UK. Would new, moredangerous technology follow a similar trend?Reported attacks (thousands)4321USUK02009 2010 2011 2012 2013 2014But with an infrared laser, there’s no suchlimitation – people might blink more, butnot turn away. Those using such devices mayalso ignore limits because they can’t see theirtargets react. “Safety limits might be exceededbecause there’s no visible effect for the user:‘I’ve been using it for 5 seconds and nothing ishappening, I’ll keep using it’,” says Coleman.And anyway, he adds, the device is simply notsuitable for police use. “Weapons like pepperspray, tasers,and even firearms, disablesuspects so they can be taken into custody.This blurs vision. The range of circumstancesin which it could be used is very limited.”Combining the infrared beam with avisible laser could get around some of theseproblems, Rockwell believes. This pairingcould disrupt vision more effectively indaylight, at lower energy levels, he suggests.SOURCE: FAA/CAA“There may be an optimal configurationwhich allows higher exposures before adangerous level is reached.”On the other hand, this combination couldalso increase the potential for blinding insome people, Rockwell and his colleaguessay. The eyes of people who are long- or shortsightedare unable to focus light on the retina,and thermal lensing might provide exactly thechange their eyes need for perfect focusing.The device could temporarily improve theirvision and so cause serious eye damage.Close to marketIt might be some time before the militaryturns infrared lasers into practical weapons,but others may not take so long. Last year,security equipment provider Shield DefenseSystems of Reno, Nevada, announced a“retinal obfuscation” device called Z-RO.The company’s website claims it blocksvision for 10 to 15 minutes, but will notdamage the retina or cornea “as these arenot targeted to achieve the visual obfuscationeffect”. Although the company won’t discussthis technology, its details appear to matchthe US air force’s thermal lensing laser. Shieldclaims Z-RO is in the manufacturing stage,and should be available soon.Whatever happens, lasers operatingat a wavelength of 1320 nanometres arealready used in research labs, for medicaltreatments such as scar removal and in opticalcommunications systems. Shrinking theselasers to weapon-size portability remains achallenge, but laser technology is advancingrapidly, so this may not take long. And that’swhen the real problems could begin.Some of the challenges arising from small,portable lasers are already evident. Accordingto the US Federal Aviation Authority, in the USalone there are 11 incidents every day in whichpilots are targeted with small but powerfullaser pointers (see chart, above). This hascaused eye injuries, but no crashes so far.Bus, truck and train drivers have also beentargeted. Some incidents have led to accidents.Authorities have a chance of tracing peoplewho use visible lasers. That would be muchmore difficult if they were wielding a thermallaser. “There would be much potential formisuse by criminals and irresponsiblepeople, against car drivers, pilots or forrobbery,” says Altmann. Even the victimmight be unaware of what was happening.“Only a small percentage of those exposedhave reported any sensation of heating,” saysRockwell. “Except for the visual effect, mostare unaware of the exposure.”It’s a sobering thought. The truth is, ifthere’s one thing worse than knowing you’rethe target, it’s not knowing. ■David Hambling is a writer based in London, UK7 March 2015 | NewScientist | 45

CULTURELABFrom grey matter to youSplit brains told us a lot, but the mystery of mind eludes us still, finds Anil AnanthaswamyTales from Both Sides of the Brain:A life in neuroscience by Michael S.Gazzaniga, HarperCollins, $28.99The Future of the Brain: Essays by theworld’s leading neuroscientists editedby Gary Marcus and Jeremy Freeman,Princeton University Press,$24.95/£16.95“HOW on earth does the brainenable mind?” This line from thepreface to Tales from Both Sidesof the Brain by neuroscientistMichael Gazzaniga serves as theoverarching question for his latestbook. And it’s also a question thatpermeates The Future of the Brain,a collection of essays edited bypsychologist Gary Marcus andneuroscientist Jeremy Freeman.But what a difference in thetechniques the authors use toexplore the answers. Gazzaniga’sbook is a deep dive into his ownpersonal and professional lifeand, as such, it’s filled withanecdotes that reveal not justthe science but also the scientists,their passions, foibles and follies.His journey begins in the early1960s as a graduate student at theCalifornia Institute of Technology,where he worked with people withsplit brains. His advisor was RogerSperry, the neuroscientist whopioneered the study of animalswhose brain hemispheres hadbeen surgically separated.It was also a time whenneurosurgeons were beginningto treat severe drug-resistantepilepsy by cutting the corpuscallosum, the bundle of nervefibres that connects the brain’stwo halves, to stop the spreadof epilepsy’s electrical storm.Sperry got Gazzaniga studyingsomeone who had undergone thisprocedure – setting him on coursefor a life of scientific discovery.The book is an intimate look at asimpler time, when deep insightscould be gleaned by designingdeceptively simple yet elegantexperiments, such as showingobjects to the left or right visualfields of people with split brainsand analysing their responses.Such work led Gazzaniga tohis theory that the left brain isan “interpreter”, trying to makelogical sense of our experiences –even when information is onlyperceived by the right brain andisn’t reaching the left. “Thoughthe left hemisphere had no clue,it would not be satisfied to stateit did not know. It would guess,prevaricate, rationalize, look for“ Feynman offered himselfup for split-brain surgery ifGazzaniga guaranteed he’dstill be able to do physics”a cause and effect, but it wouldalways come up with an answerthat fit the circumstances,” writesGazzaniga. Above all, he says, it is“the special device… that givesour actions one narrative and thesense that we have but one mind”.Whether you like reading abouthow such insights happen or caremore about the people who havethem, Gazzaniga amply delivers.Personally, I enjoyed interludessuch as the Caltech party whereRichard Feynman offered himselfas a subject for split-brain surgery,if Gazzaniga guaranteed hewould still be able to do physics.Gazzaniga writes that “Feynmanstuck out both left and right handto shake on the deal!”There’s no such levity in TheFuture of the Brain, a collectionof accessible but academicallyinclined essays charting whereLeft brain, right brain: thedifferences tell us about the wholeneuroscience is headed. Amongthe contributors are Ned Block,George Church, Christof Koch,as well as May-Britt Moser andEdvard Moser – 2014 Nobelists.Many of the essays point to afuture of high-resolution mapsor brain atlases, showing genes,connections or brain activity, andtaking us well beyond today’sfMRI and PET scans. For example,techniques that tag individualneurons with any one of ahundred fluorescent proteins, ormake brains optically transparentwill transform imaging.The technologies will generatelots of data, and neuroscientistswill need large-scale simulationsand brain models to make senseof it. Editors Marcus and FreemanPHILIPPE LOPPARELLI/TENDANCE FLOUE46 | NewScientist | 7 March 2015

For more books and arts coverage, visit newscientist.com/culturelabsay that we had better get usedto seeing the brain as an organthat carries out computations – anotion that is often resisted. Theywrite that “nerve cells exist tocompute; the real trick is to figureout what they are computing”.And as we figure that out, willneural interfaces be far behind?The most far-reaching technologyimagined in the essays is “neuraldust” – specks of silicon coupledto piezoelectric crystals thatstimulate and record activity fromneurons. These devices would besprinkled throughout the brain,communicating to a receiver onthe skull via ultrasound.They sound scary. I would havewelcomed more on the ethics ofsuch technologies, building onbioethicist Arthur Caplan’sargument that mapping thebrain must be about more thanjust gathering information anddiscussing how to use it. Caplanwrites: “Scientists must alsodebunk hype, allay groundlessfears, and anticipate… ways inwhich efforts may be made toexploit or dupe the public in thename of knowledge derived frombrain maps, studies, and scans.”It’s a welcome cautionary note,as is a caveat in Block’s essay,advocating clarity about therelationship between brainactivity and psychologicalexperience. He writes that“massive quantities of dataalone cannot produce theoreticalbreakthroughs in understandingthe mind at a psychological level”.Koch and Marcus end with afuturistic essay, looking back from2064 and hoping for a solutionby then to the “hard problem”of how subjective feelings, andconsciousness itself, emergefrom a physical brain. Maybein that future a neuroscientistwill also write a popular accountspanning the momentous50 years that answeredGazzaniga’s question of how onearth the brain enables mind. ■Anil Ananthaswamy is a consultant forNew ScientistOne funeral at a time...Which scientific ideas ought to die? Simon Ings finds outThis Idea Must Die: Scientifictheories that are blocking progressedited by John Brockman, HarperPerennial, $15.99/£9.99THE physicist MaxPlanck had a bleakview of scientificprogress. “A newscientific truthdoes not triumphby convincing itsopponents...” hewrote, “but rather because itsopponents eventually die.”This is the assumption behindThis Idea Must Die, the latestcollection of replies to the annualquestion posed by impresario JohnBrockman on his stimulating andby now venerable online forum,Edge. The question is: which bitsof science do we want to bury?Which ideas hold us back, trip us upor send us off in a futile direction?Some ideas cited in the bookare so annoying that we wouldbe better off without them, eventhough they are true. Take “brainplasticity”. This was a real thingonce upon a time, but the phrasespread promiscuously into somany corners of neurosciencethat no one really knows whatit means any more.Other ideas, especially inthe more anthropocentricallyinclined sciences of economicsand computer science, reflectmore our natural bent for binaryoppositions and good stories thanthey reveal real things about theworld. This is where things getvery interesting indeed, makingBrockman’s latest book essential,as well as enjoyable, reading.More than any amount ofView from the grave: to progress,science must bury its opponentspontification (and readerswouldn’t believe how many newbooks agonise over what “science”was, is, or could be), Brockman’sposse capture the essence ofmodern enquiry. They show whereit falls away into confusion (theuse of cause-and-effect thinkingin evolution), into religiosity(virtually everything to do withconsciousness) and cant (forexample, measuring nuclearrisks with arbitrary yardsticks).This is a book to argue with –even to throw against the wall attimes. Several answers, cogent inthemselves, still hit nerves. When“ The next person to askJulia Clarke about the firstbird will probably get acake fork in their eye”Kurt Gray and Richard Dawkins,for instance, stick their knivesinto categorisation, I was leftwondering whether scholastichand-waving would really be animprovement. And Malthusianideas about resources inevitablygenerate more heat than lightwhen harnessed to the verydifferent agendas of Matt Ridleyand Andrian Kreye.On the other hand, there ispleasure in seeing thinkers forcedto express themselves in just afew hundred words. I carry no flagfor futurist Douglas Rushkoff orpsychologist Susan Blackmore,but how good to be wrong-footed.Their contributions are amongthe strongest, with Rushkoffdiscussing godlessness andBlackmore on the relationshipbetween brain and consciousness.Every reader will have afavourite. Mine is palaeontologistJulia Clarke’s plea that peoplestop asking her where feathereddinosaurs leave off and birdsbegin. Clarke offers lucidglimpses of the complexitiesand ambiguities inherent indeciphering the behaviour oflong-vanished animals from thinfossil data. The next person to askabout the first bird will probablyget a cake fork in their eye.This Idea Must Die is garrulousand argumentative. I expected noless: Brockman’s formula is triedand tested. Better still, it shows nosign of getting old. ■ALAN THORNTON/GETTY7 March 2015 | NewScientist | 47

www.NewScientistJobs.comIncorporating ScienceJobs.comTo apply online visit newscientistjobs.comEast Coast Office225 Wyman StreetWaltham, MA 02451Email NSSales@NewScientist.comPhone 781 734 8770Calls may be monitored or recorded for staff training purposesAdvancedResearch Coursesin Woods Hole, MassachusettsFaculty PositionGenerous scholarship support available.CONTACT:Admissions CoordinatorMarine Biological LaboratoryWoods Hole, MA508.289.7401admissions@mbl.edumbl.edu/educationMBL courses derive major support from grants awarded by Howard Hughes Medical MBL is an EEO/Affirmative Action/Disabled/Veterans EmployerInstitute, the Burroughs Wellcome Fund, and the National Institutes of Health.and an affiliate of the University of Chicago.The Department of Molecular and Cell Biology at theBoston University Henry M. Goldman School of DentalMedicine has an opening at the Assistant, Associate, or FullProfessor level. Individuals with an outstanding publicationrecord and an ongoing NIH R01-funded research programDUHHQFRXUDJHGWRDSSO\:HVHHNTXDOL¿HGFDQGLGDWHVZLWKresearch interests in biochemistry, cell and developmentalbiology, molecular genetics, or craniofacial and oralbiology. Excellent laboratory facilities and start-up fundsare available as well as joint appointments with appropriatedepartments at the School of Medicine and participation inthe Bioinformatics Program at the School of Engineering.4XDOL¿HGDSSOLFDQWVVKRXOGVXEPLWD&9DEULHIVXPPDU\of research accomplishments, a description of plans forfuture work, and names of three to six references.Email all materials to: Dr. P. C. Trackman,Search Committee Chair at mcbdept@bu.eduPlease visithttp://dentalschool.bu.edu/research/molecular/index.html%RVWRQ8QLYHUVLW\LVDQ$I¿UPDWLYH$FWLRQDQG(TXDO2SSRUWXQLW\(PSOR\HUAssistant Professor Faculty PositionUniversity of Pittsburgh Cancer Instituteand University of PittsburghDepartment of Pharmacology & Chemical BiologyApplications are invited for a tenure-stream Assistant Professor-level faculty position at the Universityof Pittsburgh Cancer Institute (UPCI), specifically a PhD scientist working in the area of breast cancerbiology, prevention and/or treatment. The incumbent will have primary appointment in the Departmentof Pharmacology & Chemical Biology, University of Pittsburgh.The University of Pittsburgh, School of Medicine ranks among the top 10 NIH-funded academicmedical centers, and the department is consistently one of the top 10 NIH-funded Departments ofPharmacology. At UPCI, faculty and lab personnel have access to state-of-the-art shared facilitieswith animal care, microscopy, mass spectrometry, high throughput drug discovery, translationalresearch and clinical pharmacology analytical capabilities. The UPCI laboratories and sharedresources are located in the Hillman Cancer Center and Magee-Womens Research Institute.Successful candidates should have a track record of extramurally-supported research grantfunding, a strong publication record and excellent communications skills. Salary and benefits will becommensurate with experience.Applicants should provide a one-page statement of research objectives, curriculum vitae, and contactinformation for three professional references to:Dr. Maryann Donovan, PhD, MPHAssociate Director for Research Administration, UPCIC/O Lola Thompson5150 Centre Avenue, Suite 532Pittsburgh, PA 15232Email: thompsonla3@upmc.eduThe University of Pittsburgh is an Affirmative Action/Equal Opportunity Employer.Bates College, Faculty Position, BiologyVisiting Assistant Professor of Evolution and Conservation Biology- Biology R2706Location: Lewiston, MaineThe Biology Department of Bates College invites applications for a 1-year, fulltimefaculty position in evolutionary biology and conservation biology, beginning1 August 2015. Teaching responsibilities comprise five courses per year, includingan upper-level evolution course, a conservation biology course, two offerings ofan entry-level evolution course open to all majors, and an additional course relatedto conservation biology or environmental studies. Supervision of undergraduatethesis research is also expected.QualificationsPhD or ABD required by start date. We welcome applications from all individualswith the ability to contribute to the college’s continuing commitment to social andcultural diversity, inclusiveness, and the transformative power of our differences.The search committee asks applicants to identify their strengths and experiences inthese areas and describe how their research, teaching, and/or outreach can furtherthis goal.Application InstructionsReview of applications begins 15 March 2015, and will continue until the positionis filled. Applicants should submit in PDF format, a cover letter, curriculum vitae,unofficial graduate transcripts, and statements on teaching and research. Pleasealso arrange for the submission of three letters of recommendation, in PDF format.Employment is contingent upon successful completion of a background check.Please email academicservices@bates.edu for further consideration, and don’tforget to mention you saw us in New Scientist Magazine.48 | NewScientist | 7 March 2015

www.NewScientistJobs.comSUMMER PREVIEWJune 4 - 5, 2015Ann Arbor, MichiganApply online: February 16 - March 31medicine.umich.edu/postdocThe University of Michigan Medical SchoolPostdoc Preview will introduce graduatestudents in the biomedical sciences to theextensive research and training opportunitiesat Michigan. During a fully-funded visit, recruitswill interview with prospective mentors andnetwork with current postdocs.Eligibility:Applicants must be U.S. citizens or permanentresidents or be currently enrolled in a U.S.graduate institution.BioinformaticsBiological ChemistryBiophysicsCancer BiologyCell BiologyComputational BiologyDevelopmental BiologyResearch Areas:Human GeneticsImmunologyMicrobiologyMolecular PathologyMolecular PhysiologyNeurosciencePharmacologySAVE THE DATE!Fall Preview will be held October 15 - 16, 2015Application will open in JulyDirectorSpace Telescope Science InstituteBaltimore, MarylandThe Association of Universities for Research in Astronomy (AURA) seeks a newDirector for the Space Telescope Science Institute (STScI). STScI is located atseveral sites on or around the campus of the Johns Hopkins University in Baltimore,Maryland. STScI is operated by AURA under contract with NASA to conduct thescience program of the Hubble Space Telescope (HST) and to develop the Scienceand Mission Operations Center for the James Webb Space Telescope (JWST).STScI also operates the Barbara A. Mikulski Archive for Space Telescopes (MAST)for NASA. In the case of HST, the Institute solicits and selects observing proposals,supports observers, plans and carries out the scientific observations, calibrates andarchives the data, and distributes grant funding. For JWST, the Institute is currentlydesigning and building the ground system, as well as the systems required to alignand maintain the telescope and instruments, in preparation for taking responsibilityfor both mission and science operations in 2019. STScI is, and will be, responsiblefor the Education and Outreach activities of both of these very prominent missions.STScI has a world-renowned professional staff of approximately 600 which includesscientists, engineers, technicians, education/outreach specialists and administrativepersonnel. STScI’s scientific staff conduct world-class research to carry out NASA’smissions. STScI is committed to developing and maintaining a dynamic, diverseand inclusive workplace which enables innovation as well as scientific and technicalexcellence.The STScI Director is responsible for the overall operation of the Institute withinAURA and NASA policies and guidelines. The Director leads all aspects of theInstitute. The Director interacts with many stakeholders, including representativesof NASA, the European Space Agency, the Canadian Space Agency, leadersof industry, members of Congress, the astronomical community, oversightcommittees, Institute staff and the public at large.The Director should possess broad scientific vision and have established a strongrecord of achievement and leadership, preferably in astronomy or a closely relatedfield. The Director should also have demonstrated the skills and experiencecritical for administration and management, and be adept in organizationaland international relations. The successful candidate will possess excellentcommunication and negotiation abilities. The new Director should continue towork with the community to identify potential new missions, carry out studiesfor them, and to partner with the community to enable such missions. Currently,the Institute is working on concepts for WFIRST/AFTA and next generation spacetelescopes. The new Director of STScI must be poised to lead the organization,working with our partners, the scientific community and the public through thechallenges of transitioning the Institute to HST’s successor mission, the JamesWebb Space Telescope.AURA/STScI offers an excellent compensation and benefits package. The SearchCommittee will begin evaluating applications on March 15, 2015. Applications willbe accepted until the position is filled. Applications will be held in confidence at thecandidate’s request. Interested candidates are requested to submit a letter providinga summary of the candidate’s interest in the position as well as an overview ofthe candidate’s relevant experience and accomplishments, a curriculum vitae/resume and a list of at least three references. The Search Committee also welcomesnominations.Materials and nominations should be submitted todirectorsearch@aura-astronomy.org and addressed to:Garth Illingworth, ChairSTScI Director Search Committee, C/o AURA1212 New York Avenue NW, Suite 450Washington, DC 20005AURA/STScI sees the diversity of our staff as a strategic priority in our desire to create a first-ratescientific community. We reflect that deep commitment in strongly encouraging women, minorities,veterans and disabled individuals to apply for these opportunities.EEO/AA, M/F/Veteran/Disabled7 March 2015 | NewScientist | 49

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LETTERSIs anyone out there?From Ian SimmonsJohn Bailey’s pessimistic view thata lack of alien visitors indicatesthere are no aliens out there(21 February, p 54) carries with ittwo hidden assumptions: anadvanced civilisation will aspireto interstellar travel, and theywill develop the means to do so.It may be that interstellar travelcannot be achieved on timescalesthat are meaningful to livingorganisms. Voyager I, humanity’smost distant space probe, won’tactually leave the influence of thesun’s gravity for another 17,000years, let alone reach another star.Anything we are likely to buildin the foreseeable future won’t domore than shave a few thousandyears off that, and whatcivilisation is going to sit aroundfor 10,000 years awaiting ananswer from a probe it’s unlikelyto even remember it sent?It is now over 40 years sincewe even sent anyone to the moon,and a combination of economicsand politics has stifled our abilityto get out of Earth orbit sincethen, let alone reach for the stars.Similarly, alien civilisationsmay be out there, but have nevermanaged to visit us simply dueto budget cuts.Monkseaton, Tyne and Wear, UKFrom Adrian EllisJohn Bailey concludes that sincewe haven’t been bombarded withself-replicating alien space probesor spotted heat signatures inspace, there probably aren’t anyadvanced civilisations living inour galaxy.He seems to think thatadvanced races will have a “moreis better” philosophy, but climatechange is showing us that theopposite is the only intelligentlong-term strategy.If this is correct, then the moreadvanced an alien race is, the lessvisible they will be. It’s the quietones that are clever, not theshouters.Hampton, Middlesex, UKFrom Neil DohertyWe ought not to fear attractingadvanced aliens throughinterstellar signals (21 February,p 8). Considering the chances ofany sentient life having thetechnology to detect, recogniseand understand our signals, andthe distances involved to travel toits source, we will be a veryadvanced race ourselves by thetime they arrive.Barnsley, South Yorkshire, UKSome crap questionsFrom Philip AbbottJessica Hamzelou describes theenormous influence intestinalbacteria have on the behaviour ofthe human body (14 February, p 8).I wonder if this casts doubt onthe validity of epidemiologicalstudies on the diet. Could thebenefit of a Mediterranean dietbe dependent on a Mediterraneanfaecal biota?To my knowledge,standardisation of faecal biotaisn’t a feature of dietary surveys.Surely the effect of diet can onlybe meaningful if this factor istaken into account – especiallyif a faecal transplant can triggerobesity, as Hamzelou describes.As a final thought, when one ischoosing a faecal donor, it maynot pay to choose someone withan active sporting lifestyle. Thephysical fitness might becompensating for deficienciesin the microbiome. Would it notbe better to choose a healthycouch potato whose biota arekeeping them fit, despite theirinactive lifestyle?Teddington, Middlesex, UKThe fine germ lineFrom Jeremy GreenwoodI agree with Michael Le Page’sargument for genetic alteration ofembryos to treat those with majorabnormalities (14 February, p 26),but where do you draw the line?Congenital deafness? A geneticpredisposition to cancer?A predisposition to stammering?I stammer, and am pleased I wasnot interfered with at conception.I think that as technologyimproves and such interventionsbecome routine there is the riskof laudable intentions towardsperfection taking the whole thingtoo far. Some genetic disordershave benefits. Sickle cell disease,for example, confers a level ofprotection against malaria.There will be other benefitsattached to less-severe diseasesthat we are not aware of. We cannever accurately foretell thefuture, so reducing our geneticdiversity is not without peril.There may well be a value tonature’s lottery.So yes, let’s have germ-linealterations, but these shouldonly be for a very limited rangeof defined conditions, and neverdone without counselling andinformed consent.Bacup, Lancashire, UKPredicting troubleFrom Geoff RoweHal Hodson draws our attentionto the increasing prevalence ofautomated systems that tend tobe driven by predictive equations(7 February, p 30).These equations often have onething in common: they rely onincomplete and proxyinformation to make theirpredictions. It is sobering toconsider how accurate similarpredictive equations are in fieldslike medicine or epidemiology.Although valuable insightsare gained from epidemiologicalstudies, say, the predictiveequations derived from themmay not be good enough topredict individual choice,behaviour or risk. This can be putdown to the use of incomplete,inappropriate or inaccurateindicators.The public should be givenassurance that the predictiveequations used in banking ornational intelligence meetexceptionally high standards.Ottawa, CanadaNo need to frackFrom Steven WhiteIn examining whether the UKshould press ahead with frackingfor gas, you write that a lot ofimported gas originates in Russia(14 February, p 10).But according to governmentfigures, the gas we import comesprimarily from Norway, Qatar andthe Netherlands. The prevalentmisconception that we need tofrack to keep the lights on, andthat we get our gas from Russia,makes it hard to have a sensibledebate on energy security, andwhether we should risk going “allout” for shale gas in this country.As a resident of the north ofEngland, I’d much prefer to seeinvestment in energy sourcesthat start us on the path todisplacing fossil fuels.York, UK■ The editor replies:You are correct. We meant to saythat importing more gas to theUK could increase demand forRussian gas in other countries.Myco-cocoFrom Craig SamsColin Barras credits the leaf shapeof the coco de mer tree for thehigh level of nitrogen andphosphorus in the soil around the7 March 2015 | NewScientist | 53

LETTERSTo read more letters, visit newscientist.com/letterstree, as it funnels rainwater andthe nutrients it picks up down thetrunk, but there is anotherexplanation (14 February, p 13).The dense, fibrous root zoneof this palm plays host to acommunity of mycorrhizal fungithat ferry otherwise unavailablephosphorus to the tree. The fungialso provide carbohydrate energyto the nitrogen-fixing bacteria inthe soil.Rainwashed nutrients maywell play a role, but unless theresearchers measured themicrobial levels in the rootzone the contribution of theseorganisms should not be ignored.Hastings, East Sussex, UK■ The editor replies:This is a very good point, and theresearchers are looking intooptions to study the potentialrelationship between coco de merand mycorrhizal fungi.Microbial goldFrom Brian KingI don’t think it is disputed thatthere was some biologicalcontribution to the formationof the gold deposit in theWitwatersrand basin (7 February,p 11). Since its discovery, varioustheories have been put forwardas to how the deposit formed,including sedimentation,hydrothermal processes andprecipitation by microbes.That gold can form underanaerobic conditions is wellknown and by the late 1960sphotomicrographs clearly showedthe close association of some ofthese minerals with microbes,but this is relatively rare. It isgenerally believed that theWitwatersrand gold originated inthe Archean greenstone belts tothe north, south and west. Thecurrent exposures of these rocksall contain gold and most havebeen or are being exploited.Much of the gold now lies inconglomerates believed to havebeen laid down in fluvial fans.I understand that only in thedistal parts of the fans in theWitwatersrand is there abiological association withminerals, mainly gold anduraninite.Barton on Sea, Hampshire, UKCancer coasterFrom Chris GoodPeter Borrows asks if rollercoasters could be used to treatbrain cancer (14 February, p 55).The answer is no.The brain producescerebrospinal fluid. Most of thisfluid passes out to bathe the outersurface of the brain and spinalcord, from where it is reabsorbed.Anything blocking this flow, suchas a tumour, will lead to a lifethreateningincrease in pressurewithin the brain.A sudden change in theposition or motion of the head,such as on a roller coaster, maymove a tumour away from thedrainage channel, unblocking itand temporarily relieving thepressure. But this is only atemporary measure and surgeryis still required to remove thetumour.Maidenhead, Berkshire, UKNo proving godFrom Kate FlemingTheists and atheists can atleast agree on one importantstatement: “There is no suchthing as god” (21 February, p 54).For the theist, this isn’t becausegod isn’t real, but because godisn’t a thing. God by definition isthe author and sustainer ofcreation; not an item within it.Faced with creation, a theistdraws the conclusion that acreator is responsible. Trying topin god down using the scientificmethod is like attempting toexperience the creative powersof Beethoven through chemicalanalysis of the ink on hismanuscripts. We can do it, but itdoesn’t get us very far.London, UKMegaflood follyFrom Ayman AsfourIn his article on megaprojects,Michael Marshall discussesflooding the Qattara depressionin Egypt (3 January, p 34). This isan old idea that will lead to thecreation of another Dead Sea.Evaporation will graduallyincrease the salinity of the wateruntil a supersaturated salt lake iscreated. The salt water will seepunder the desert sand andcontaminate the undergroundfreshwater reservoirs that supplythe nearby oases of Siwa and Qara.Finally, the salt water will causethe groundwater level to rise andflood the oases in the desert.Please proceed with dammingthe Atlantic or the Mediterraneaninstead.Toronto, CanadaDangerous danceFrom Donald WilsonI was upset by the bad pressgiven to Scottish countrydancing by Roger Malton(14 February, p 55).This type of dancing shouldcertainly not be high impact,nor cause any twisting if done inproper light shoes on a suitablefloor. It is in fact very healthyexercise for both mind and bodywith a large “feel-good” factor,and very few resultant injuries.I started Scottish countrydancing nearly 60 years agoand recently held a ball tocelebrate my 80th birthday.Most of the dancers were notyoung, but they were certainlyall fit and energetic.Coton, Cambridgeshire, UKBaby boom and bustFrom Eric KvaalenHealth minister Beatrice Lorenzinneedn’t worry about Italy’s fallingbirth rate (21 February, p 8).If each woman has 1.39 children,it will take about 49 generationsfor the population to fall to 1 (atwhich point Italians willpresumably go extinct).There’s nothing to fear from alower population. Historically,Italy has always had a lowerpopulation than now.Les Essarts-le-Roi, FranceFor the record■ An error landed in our story onmeteors (21 February, p 13): ManuelMoreno-Ibàñez is affiliated to theInstitute of Space Studies (CSIC-IEEC)in Barcelona, Spain.Letters should be sent to:Letters to the Editor, New Scientist,110 High Holborn, London WC1V 6EUFax: +44 (0) 20 7611 1280Email: letters@newscientist.comInclude your full postal address and telephonenumber, and a reference (issue, page number, title)to articles. We reserve the right to edit letters.Reed Business Information reserves the right touse any submissions sent to the letters column ofNew Scientist magazine, in any other format.54 | NewScientist | 7 March 2015

7 March 2015 | NewScientist | 55

FEEDBACKFor more feedback, visit newscientist.com/feedbackPAUL MCDEVITTIDLY reading a random back issue ofNew Scientist in the bathroom, wecame across a letter from David Marjotreminding readers of Hickam’s dictum(19 October 2013, p 30). We feel thisexception to the much better knownOccam’s razor deserves more notice.Hickam’s dictum holds simply that“a patient can have as many diseasesas they damn well please”. Take, forexample, someone showing up at aclinic with a headache, fever, runnynose and excruciating pain in a big toe.Occam’s razor – often given as “do notmultiply entities unnecessarily” –suggests a diagnosis of improbablitis,a single entity that covers all thesymptoms but is spread only by riverworms in the land of Nonexistentia.On the other hand, the unfortunatecould have flu on top of gout.OCCAM’S razor is notable thesedays for people using and abusingit to justify their non-standardmentation – particularly aboutconspiracy theories. It can also beapplied to debunking these:perhaps introducing a remotecontrolledholographic missileequippedpassenger plane doesnot help to understand events atthe Pentagon in Washington DCon 11 September 2001?Its modifier, Hickam’s dictum,described above, has similarutility. A tragedy may have morethan one contributing cause:perhaps the Pont de l’Alma roadtunnel in Paris, France, wascrowded, and the driver of the carbearing Diana Windsor not sober?Indeed, it remains to be seenwhich may need to be wielded inresponse to the flood of paranoidpostings we sadly predict willfollow our report on new laserweapons that induce temporaryblindness (page 44).THERE is little new under the sun.While surveying the rather sparsereferences to Hickam’s dictum, weencountered Walter Chatton, a14th-century contemporary of Williamof Occam (or Ockham) who arguedphilosophy with him. So far, weunderstand that Chatton proposeda set of principles for when it makessense to introduce a “new entity” toyour theory, contrary to Occam’s razor.We hope, one day, to emerge from ourReader Paul Smith suggests “selling homeopathicpreparations of rhino horn and sending allprofits to rhino conservation”. Nice subversion offruitloopery. First, a discussion of ethics…present pit of late-medievalphilosophical discourse bearing agem of crystalline clarity.DETECTING fake journals isanother area in which thecompeting principles of Occamand Hickam may be in tension,constructively. It’s increasinglydifficult to tell the “hopefulmonsters” – that is, publicationshoping to have evolved newbusiness models that makeeverything in the academicpublishing garden rosy – fromthe scams.Joan Curzio seeks our helpevaluating arcjournals.org – andwe’re stumped. The solicitingletter is arguably in perfectly goodIndian English. The lack of namededitors-in-chief for the medicaljournals due to launch on 10 Aprilmay be a website flaw. The papersreferencing Ayurvedic principlesare beyond us.MEANWHILE an organisation calledACI InSights sends Feedback aninvitation to “Revolutionize yourResearch with the world’s onlyrepository of published scholarly blogcontent”. Hypothesis: the contentmay not be fully state-of-the-art.Experiment: list the contributionsrelating to climate change. Result: awhole series of blog postings by JudithCurry, whose perspective could bedescribed as non-standard, such as“Climate psychology’s consensusbias”. Need to introduce new entitiesto our hypothesis: none, yet.CLEARER cases are those ofComputational Intelligenceand Electronic Systems and theAperito Journal of NanoScienceTechnology. The headline of anews article about the two, sent byPhilip Clapham, tells most of thestory: “When Maggie Simpson canget a paper into a science journal,you know you’ve got trouble.”Alex Smolyanitsky, a Coloradobasedmaterials scientist, followedup Feedback’s intermittentrunning story (most recently28 June 2014) on the SCIgenprogram, which generates utternonsense vaguely in the form ofa computer science paper. Hesubmitted a pseudopaper to bothjournals, pseudonymously.PONDERING Hickam’s dictum,Feedback wonders about a roughlyequivalent principle in risk analysis.It has long seemed to us that anyonewho suspects the probability of a setof independent failures occurringtogether to be vanishingly smallshould urgently make plans to copewith them all happening at once.Nuclear accidents provideexamples – but not, as far as we cantell, a name. Can you help?FINALLY, it is time to excavatefrom our piling system a responseto our query about whetherreaders were celebrating PiApproximation Day on the (UKformat) date 22/7 (12 July 2014).“I imagine,” Andrew Green writes,“that there is great excitementin the Pi community aboutcelebrating at 9:26 and 54 secondson the [US format] date 3/14/15,although the celebrations may besomewhat transitory”.Of course 3/14/15 9:26:54 is theclosest we’ll get to the precisevalue of the constant that relatesthe circumference of a circle to itsdiameter for, ooh, ages. So: howwill you toast pi next week?You can send stories to Feedback byemail at feedback@newscientist.com.Please include your home address.This week’s and past Feedbacks canbe seen on our website.56 | NewScientist | 7 March 2015

THE LAST WORDLast words past and present at newscientist.com/lastwordMind lags bodyI’m 77 and, like many people my age,tend to stoop rather than stand upstraight. A few months ago I wasstanding by the kitchen door, talkingidly. For some reason I turned and hitmy head a stunning blow on the doorframe. More recently I was lookingover my wife’s shoulder as she workedon her computer; I reached out myhand, pointing to something on thescreen. As I pulled my hand back, myfingers got caught in a box on thetable and I toppled it over on to thefloor, spilling its contents. After awhile I realised that both times I’dbeen stooping. In my mind’s eye myhead was clear of the door frameand my hand well above the table,but my stoop cancelled both. Is ourbody image slow to adjust to reality?If so why, and can it be fixed?■ The subconsciousperception of your bodyorientation and movement iscalled proprioception. This aspectof awareness is supplied by thevestibular system in the inner earand by nerves in the muscles andjoints. It lets you know where yourhands and feet are when you areblindfolded.Proprioception is learnedthrough experience, but can becompromised by changes in bodystructure due to injury, ageing oradolescence. Teenagers who gothrough a growth spurt may,when playing sports, start todrop balls that they used to catch;their arms are now longer thantheir brain remembers. Theadolescents’ proprioception lagsbehind their growing bodies.However, neuromuscularpathways can be retrained withspecific practice: evidence showsthat juggling helps cricketers.The correspondent’sproprioceptive experience isbased on more than 70 years ofstanding tall. This conflicts withhis current stoop and results inaccidents. The good news is thatmovement and awarenessexercise such as t’ai chi or yoga notonly improves proprioception,but diminishes the likelihood ofthe falls and broken bones that arethe bane of older people.David MuirEdinburgh, UKTree timeIt is generally accepted that theincrease in day length in the springis what prompts deciduous trees tobegin growing their leaves. But howdoes a tree know that the days aregetting longer?■ Everyone knows that plantsneed light to grow, and thatmost plants grow in differentways at different times of theyear, particularly in temperatelatitudes. This effect, calledphotoperiodism, enablestemperate plants to control whenthey grow new leaves and whento drop them in the autumn.However, it isn’t the length ofthe day which is important, butthe uninterrupted dark period –the length of night. During theperiod of darkness the plantproduces a photosensitiveprotein called phytochrome, theconcentration of which controlsthe onset of dormancy in autumnand bud burst in spring.Even a small amount of electriclight during the hours of darknesscan upset this, and it is noticeablewhen a tree encroaches on a streetlight. In autumn, when the tree isstarting to become dormant, theleaves closest to the light are oftenthe last to fall. However, trees andplants are unaffected by lightfrom the moon.John CroftsSherwood, Nottinghamshire, UK■ Back in 1920, botanistsWightman Wells Garner andHarry Ardell Allard thought thelength of daylight was the key tophotoperiodism. So by the timeit was discovered that the hoursof unbroken darkness wereresponsible, plants had alreadybeen labelled as “long-day”,“short-day” or “day-neutral”.Chrysanthemums are short-dayplants and will only flower if thereare enough hours of darkness.Growers of these plants used tokeep their greenhouse lights onall night to delay flowering, untilit was discovered that just a briefburst of light would suffice.This is down to thephotosensitive phytochromepigment. It exists in two statesand when exposed to sunlight, theamount of pigment in either stateis about the same. As night fallsmore of the pigment switches tothe active state. But a flash of lightwill redress the balance and this isenough to postpone flowering inshort-day plants or induce it inlong-day plants.Even seeds are armed with thispigment, which allows them touse the direction of sunlight tosense which way is up (thisensures shoots and roots head offin the right direction). They can“calculate” how deeply they areburied from the light intensityand can even detect the presenceof overhanging foliage andpostpone germination.Mike FollowsSutton Coldfield, West Midlands, UKThis week’s questionANGLE OF DANGLEWhat are these (see photo)?There were about 20 creatures,some headless. They werefound in Victoria state, Australia,about 10 kilometres from thecoast at Ceduna.Chris JaminonAtherton, Queensland, AustraliaThe writers of answers that are publishedin the magazine will receive a cheque for£25 (or US$ equivalent). Answers shouldbe concise. We reserve the right to edititems for clarity and style. Please include adaytime telephone number and an emailaddress if you have one. New Scientistretains total editorial control over thepublished content.Reed Business Information Ltdreserves all rights to reuse all questionand answer material that has beensubmitted by readers in any mediumor in any format and at any time in thefuture.Send questions and answers toThe Last Word, New Scientist, 110 HighHolborn, London WC1V 6EU, UK, by emailto lastword@newscientist.com or visitwww.newscientist.com/topic/lastword(please include a postal address in orderto receive payment for answers).Unanswered questions can also be foundat this URL.QuestionEverythingThe latest book of sciencequestions: unpredictableand entertaining. Expectthe unexpectedAvailable from booksellers and atnewscientist.com/questioneverything

The baffling, trivial, curious, or strange . . .KNOW IT ALLThe latest book in New Scientist magazine’sbestselling “Last Word” series presents 132science questions and answers from amateurexperts and curious minds everywhere. Find theanswers to the microscopic (Why do sand particleson a beach seem to reach a certain grain size andthen reduce no further?), the puzzling (How did theRomans express fractions?), the hypothetical (Ifhumans lived in a zero gravity space station awayfrom the sun, would skin still wrinkle and sag?),and the practical (What’s the best strategy forgetting through multi-lane traffic jams as quickly aspossible?)—any topic is fair game!KNOW IT ALL: 132 Head-Scratching Questions About the Science All Around Us$14.95 • Available in trade paperback and as an ebook wherever books are soldA Guardian Top 10 Science and Technology Book“The experts at New Scientistmagazine have published a book thatanswers some of the oddest but mostentertaining questions they’ve been asked.”—Daily Mail“Explain[s] some oflife’s great mysteries.”—reveal@experimentbookstheexperimentpublishing.comALSO AVAILABLENothing: Surprising Insights Everywherefrom Zero to Oblivion$14.95 • Available in trade paperback andas an ebook wherever books are sold