No title

SPECIAL REPORT DEEP SEA GOLD RUSH

Quest to harvest riches from the abyss

WEEKLY July 2-8, 2011

Vision as you've never seen it before

PERSONAL 'COPTERS CONFESSIONS OF A METEORITE HUNTER

No2819

US$5.95 CAN$5.95

>

WHITE DWARF WORLDS Life around the death stars

Instant expert Intelligence Our complete guide to brainpower - and how to boost it

Science and technology news

www.newscientist.com US jobs in science

I like value for money, and the freedom to change my flight. Free nuts I can do easyJet Flexi - the new business unlimited free date changes in period. Includes 1 piece of hold, 1 hand luggageand Speedy

u,......-'.

Times change The easyJet Flexi Fare is paid in full at the time of booking. Any additional services must be paid for in full, at the time of booking. No refund applies if passengers are unableto fly. Date changes and Speedy Board ing subject to availability. Datechanges must be made at least two hours before original departure time. For full Terms & Conditions see ou r Carrier's Regulations on easyJet.com

CONTENTS

Volume 211 No 2819 This issue on line

newscientist.com/issue/2819

News

News

UPFRONT Advertising to monkeys. Is asteroid the solar system's lost world? 6 THIS WEEK Murky lenses to sharpen images. Why Tasmanian devils are sit ting ducks. Unlocking the tick-tock of a nuclear clock. Faulty DNA zip may stress your children. Good at visual illusions, bad at introspection 16 IN BRIEF "Broken" toys show infants' rationality. Evidence that bird tweets use grammar. Monkeys stressed by ecotourism. Vital statistics of a famous black hole 4

:;:

6 The deep sea gold rush

~

"'z 0

"' 0 u 0

"'"'uJ: w

~

u z

5u J:

Quest to harvest riches from the abyss

).>( PERFECTLY FORMED The incredibly light, fast and strong R-Series from Toshiba Every component that goes into the new R8 range of laptops is conceived, designed and crafted with exceptional attention to detail. lt all comes together in an outstanding combination of speed, strength and mobility. In fact, the only thing you'll find missing is compromise. Available in a choice of screen sizes, the perfectly formed A-Series is available now. Take a closer look at www.toshiba.eo.uk/r-serles

TOSHIBA Leading Innovation _~> Toshlbo Is a trademllr1

Vent mining The Solwara 1 hydrothermal vent field will be mined over an area of around 0.1 km 2, in which confirmed ore deposits are up to 18 metres thi ck

AUXILIARY CUTTER Levels rough terrain to create benches - smooth platforms with gent le sl opes on which the other machines can work

- 1600m

TO SHIP

SUBS EA LIFT PUMP Receives material f rom the gathering machine and pumps it to the production support vessel on the ocean surface

•

BULK CUTTER Does most of t he mining work. Grinds up t he sea floor to a depth of 1 metre with each pass

GATHERING MACHINE Follows in the tracks of t he bulk cutter, draw ing up cut material for transport t o the surface

2 July 20111 NewScientist 17

SPECIAL REPORT I MINING THE SEABED about o .6 per cent typically found at mines on land. The deposits form when water that has percolated through rock beneath the sea floor, dissolving sulphur and metals, is ejected at temperatures of up to 350 •c into the frigid deep ocean. Black metal sulphides precipitate out, forming vent chimneys. As chimneys topple and reform, vent fields can develop into mounds of m etal-rich ore. The prospect of mining these deposits alarms many scientists who study vents and t heir creatures. A variety of worms, molluscs and crustaceans inhabit the vents - including such oddities as 2-metre-long giant tube worms (Riftia pachyptila) and the yeti crab (Kiwa hirsuta), named for its "hairy" legs and claws. What m akes these ecosystems remarkable is that the entire food web depends on microbes that get their energy by oxidising hydrogen sulphide emitted from the vents - some of which live as symbionts inside larger organisms. This chemosynthesis is fundamentally

different from the photosynthesis that sustains most life on Earth. Since the first vents were seen in 1977, new animal species have been found at a rate of about one per month, with no sign of discovery rates falling off. Given that vent ecology is still poorly understood, some researchers argue that it is too early to begin comm ercial exploitat ion. "We have really just scratched the surface of what lives in these areas," says Maurice

Tube worms such as Tevnia

jerichonana thrive in the hot water of hydrothermal vents

VENT SCIENTISTS CLEAN UP THEIR ACT There's an irony to calls from marine researchers to restrict mining at hydrothermal vents: until now, the

powerful lights of submersibles that explored the vent fields (Nature, DOl: 10.1038/18142).

But the statement lacks the teeth of an earlier draft code of conduct, put forward by Lyle

greatestthreat to these natural wonders has been overenthusiastic scientific research.

Fortunately, subsequent monitoring indicates that shrimp populations are doing fine, says

Glowka, a consultant who today is a legal adviser to the UN Convention on Biological Diversity, and marine

The alarm was sounded in 1990 by Verena Tunnicliffe at

jon Copley of the University of Southampton, UK. But it was

ecologist Kim juniper of the University of Victoria. This would

the University of Victoria in British Columbia, Canada. She studied vent sites on the juan de Fuca ridge in the north-east Pacific that

another reminder that scientists needed to put their house in order. 'The lastthing we want to do is damage them by studying them,"

have asked national research agencies to make funding conditional on abiding by the code. "lt fell flat on its face;· says Glowka.

had been visited by scientists at least three times in the 1980s. Populations of Ridgeia piscesae

Copley says. Copley is eo-chair of lnterRidge, the international body set up to

"I think it was seen as a threat." How closely scientists abide by

tube worms had plummeted at chimneys where sampling had

coordinate vent science, which in 2006 adopted a statement on

the lnterRidge statement is unclear. Earlier this year, Cindy Lee Van Dover of Duke University in North

taken place, but remained healthy at unsampled sites uournal of Geophysical Research, DOl:

responsible research.lt calls on scientists to avoid any activities that will undermine the

Carolina published a survey in which 90 per cent of researchers who responded said they followed the

10.1029/jB095iBOBp12961). In some cases, even looking at vent animals can hurt them.ln

sustainability of vent organism populations, refrain from all but essential collections and avoid

recommendations. However, half doubted whether their colleagues did- and only 5 per cent of more

1999, UK researchers found that the shrimp that congregate around vents on the Mid-Atlantic ridge had

transplanting material or creatures between sites. lt also asks researchers to share samples and

than 3000 scientists who were sent the questionnaire replied (Conservation Biology, DOl: 10.

apparently been blinded by the

information to avoid duplication.

llll/j.1523-1739.2010.01642.x).

8 I NewScientist I2July 2011

Tivey, a vent scientist at the Woods Hole Oceanographic Institution in Massachusetts. "You have the potential of wiping out a community that you don't yet know exists." That won't happen at Solwara 1, Nautilus officials insist. "The environmental impacts are going to be well managed," says Joe Dowling, the company's vice-president for communications. Indeed, Nautilus asserts that its activities at the relatively small Solwara 1, which spans just over 0.1 square kilometres - about the size of 10 football pitches - will be much less environmentally damaging than conventional mining, which typically occurs on a much larger scale. Solwara 1 is a relatively quiet vent field that includes dormant chimneys and none of the gushing "black smokers" seen at the most spectacular vents. Still, chimneys venting hot water host vibrant populations of animals including lfremeria nautilei snails andEochionelasmus ohtai barnacles, which will be destroyed by mining. Nautilus is establishing a reserve site some 2.5 kilometres away, from which larvae should recolonise the mined area once operations cease, after 30 months or so. To minimise damage from mining spoil, particles larger than 8 micrometres across will be removed by the processing ship, before waste water is returned to the ocean, about so metres above the seabed. As part of its evaluation, Nautilus commissioned independent scientists to survey both sites. They concluded that the reserve site was well chosen. "It is more diverse [than the area to be mined]," says marine ecologist Bob Kennedy of the National University oflreland in Galway, a member of the team. "Mining may be an acceptable disturbance in the context of the natural variability and disturbed nature of these vent fields." Samantha Smith, Nautilus's environmental manager, says the company will survey for recolonisation for at least three years after mining ceases and will monitor the effects of the fine sediment likely to fall on the sea bed from the returning waste water. Vent biologists contacted by New Scientist are generally impressed with Nautilus's environm ental impact

For daily news stories, visit newscientist.com/news

statement, but remain wary about the future if mining expands. ''I'm concerned, and I'm paying attention," says Charles Fisher of Pennsylvania State University in University Park. In March, the international body that coordinates vent science, InterRidge, sent the ISA a list of vent fields that it suggested should be considered for protection from prospecting. This included almost half of the 72 known active vent fields in international waters, and was based on a poll of vent scientists, some of whom wanted to protect all active sites. These are easier to find because oftheir"smoky" plumes. Earlier this year, Cindy Lee Van Dover of Duke University's Marine Laboratory in Beaufort, North Carolina, who also worked on the site assessment for Nautilus, argued in Nature that mining and prospecting should be put on hold until firm guidelines for the conservation of vent ecosystems are in place (DOl: 10.1038/470031a). That's unlikely to happen, but Adam Cook, a marine scientist with the ISA, says that the authority's legal and technical experts will issue environmental guidelines at a later date. He also points out that the prospecting that will be allowed under the ISA's exploration contracts is similar to the sampling already performed by vent researchers (see "Vent scientists clean up their act"). By the time mining takes off, if it does, guidelines should be in place. For the foreseeable future, simple economics provides some reassurance t hat vents will not be trashed en masse. Perhaps 1 per cent of vent fields contain commercially viable mineral deposits, estimates Mark Hannington, an economic geologist at the University of Ottawa in Canada. But if prices of copper and gold rise, the incentives will shift. The fear is that without strong oversight, subsequent environmental assessments may not be as rigorous as that conducted for Solwara 1. Vent fields differ radically in the species present and possibly the extent to which the animals at a particular site embody unique genetic diversity. "Every one of these developments needs an appropriate assessment," says Kennedy. "We shouldn't allow a Wild West freefor-all after one or two studies." •

Distribution of hydrothermal vent fields The Solwara 1 site is located in Papua New Guinea's exclusive economic zone and is the first vent field likely t o be mined for mineral-rich deposits. China and Russia have applied for 15-year exploration contracts to begin prospecting at sites on the Southwest Indian ridge and the Mid-Atlantic ridge

•"of.

.. ...-,_--".........

~- ·.

•

-.

,.. ••

••

~

~•

SOLWARAl

•• ~ I

PAPUA NEWGUINEA

~­

•••

HYDROTHERMAL VENT FIELDS • Active Inactive • Unconfirmed

PLATE BOUNDARIES -··-Trench - Ri dge -..-·Transform

•

International waters Exclusive economic zones

Zjuly 2011 1NewScientist 19

THIS WEEK Review Letters, measures the

Murky lenses make sharper images MacGregor Campbell

IT'S as ifHumpty Dumpty was put back together again stronger than before. Light that passes through an opaque medium, such as an eggshell, can be reassembled in sharper detail and over a wider field of view than if it passed through a transparent lens alone. Such "scattering" lenses could one day be used to see individual living cells, replacing biopsies and improving surgical precision. In 2007, Allard Mosk and colleagues at Twente University in Enschede, the Netherlands, demonstrated that materials not normally transparent to optical wavelengths can be used to sharply focus what little light gets through. By correlating input and output light, the researchers calculated a "transmission matrix" that defines how light is scattered by disordered particles

in such a material. They used this matrix to design the shape of the incoming light waves so that they scattered off the particles and came to a focus on the other side. In 2010, the researchers showed ~ that such a lens could focus light z~ into a spot one-tenth the size of ~ that produced by an ideal g transparent lens of the same size, ~ >< making the focus to times as ~ Looking through skin sharp. In May, they imaged gold f? nanoparticles at a resolution of just 97 nanometres, to show that that puts a smile on our faces scattering lenses can image below every day", says Mosk. "But it does the 200-nanometre limit of so at a cost of being rather slow conventional optical lenses and having a very small field of (Physical Review Letters, DOl: view of only a few micrometres." Now Wonshik Choi of Korea 10.1103/PhysRevLett.I06.193905). University in Seoul and colleagues It is a painstaking process, though. To create an image with have found a way to take pictures such high resolution, they had to that are a thousand times as take "zoomed in" snapshots of wide - up to several millimetres, small regions of the nanoparticles though the resolution is lower than with Mosk's method. and then stitch these images together. The technique "achieves Their technique, detailed a sub-too-nanometre resolution in a paper to appear in Physical

transmission matrix of a potential lens faster and in more detail than previous methods. They used a 450-rnicrometrethick slice offresh rat skin as a lens. First they illuminated it from different angles, capturing around 2o,ooo images of the resulting transmitted light in 40 seconds. This provided a detailed 3D model of the skin sample's transmission matrix. Then they placed a microglial cell from a rat's brain behind the skin-lens and took another image (see top image, left). They used pattern-matching software to sort through the 2o,ooo images to determine which regions of the matrix were in front of the cell. This allowed them to piece together a detailed picture of the cell (bottom image). The technique provided a field of view five times as wide as a traditional lens. This is because rays of light reflected from the target at angles too wide to be intersected by normal lenses are bent into a detector by the scattering lens (see diagram). "Our system can perform widefield imaging by converting a

Tasmanian devils were sitting ducks for cancer

Clinging on 10 I NewScientist 12 July 2011

DESPITE its ferocious nature, the Tasmanian devil is a creature faced with extinction, t he victim of a gruesome facial tumour disease. Now the first genetic sequencing of these carnivorous marsupials has revealed that we had a hand in their decline: centuries of human interference left them st ripped of genetic diversity and vulnerable to disease. This meant that when the parasitic "devil f acial tumour disease" appeared in 1996 it rapidly spread through the entire population, causing it to plummet by over 60 per cent between 1996 and today. The disease is transmitted by physical contact, mostly biting during

sex, and is almost always fatal. The International Union for the Conservation of Nature (IUCN} has now classed Tasmanian devils, Sarcophilus harrisii, as endangered, and some st udies estimate the species could be wiped out within decades. To find out why they cannot fight the cancer, Stephan Schuster of Pennsylvania State University in University Park and colleagues sequenced the genomes of two devils. He chose animals f rom opposite ends of Tasmania, which should be as genetically distinct as devils get. Yet their genomes only differed at 915,000 sites. A similar comparison showed t hat two

For daily news stories, visit newscientist.com/news

c:>-

distorted image into a clean image using the recorded transmission m atrix," says Choi. "It is very nice work," says Jochen Aulbach at the FOM Inst itute for Atomic and Molecular Physics in Amsterdam, the Netherlands. "It brings the concept of scattering len ses a big step closer to application for wide· area microscopy." "I know of no other compact optical system that combines

-

such high resolution with a field of view that large," says Mosk. He hopes to see a hybrid system that combines his resolution with Choi's speed and field of view. Ult imately, h e says, the technique could improve surgeons' views of what to cut during keyhole surgery. "Light scattering may seem detrimental to imaging, but in fact a scattering system can m ake an almost perfect lens." •

Scatter for sharpness An "opaque" lens can focus more sharply over a wider fi eld of view LIGHT ESCAPES LIGHT RAYS

OBJECT

TRADITIONAL LENS

CU±:! Q,U') OQj > CU.-

.t:.C:

Help push the boundaries of innovation and take your career to the next level''

~::J

Science. engineering and technology at The Open University. If you want to help shape our futu re while broadening your own career horizons, our wide ra nge of science, engineering and technology courses lead t o qualifications that wi ll get you noticed by th e people that matter. Our study method helps you devel op skills you can put into practice at work straight away, using a blend of study materials. online fo rums and even mobile media to help you fit study around work. Welcome to Britain's favourite university.

LIGHT ESCAPES

SCATTERING LENS The lens alters th e path of the light rays, so more light ends up at the detector

DETECTOR

-- -

SCATTERED LIGHT ENTERS LENS Chemistry Computing & ICT Design & Innovation

Health Sciences Life Sciences Mathematics & Statistics Physics & Astronomy Systems Thinking in Practice

humans from China and j apan

were left vulnerable to disease.

differ at 3,257,000 sites. Genetic analysis of a further 175 wild animals and seven museum

This is clearly at the root of their problems, says Katherine Belov of the University of Sydney. "Devils are

Engineering & Technology Environmental Science

specimens showed that devils have had a low genetic diversity for over

essentially immunological clones, so tumours pass between them without triggering an immune response."

Environmental & International Studies Geosciences

100 years (Proceedings of the National Academy of Sciences, 001: 10.1073/pnas.l102838108).

" Devils are immunological clones, so tumours pass between them without triggering a response" Humans had a big hand in this. Devils were wiped out in mainland Australia by dingoes brought in by settlers, then t hose that remained in Tasmania were hunted as pests, causing several population crashes. As their genetic diversity was slashed, the devils

The Australian and Tasmanian governments have set up a conservation programme, capturing disease-free devils to establish an "insurance population". Housed at sites like the Devil Ark in Somersby, New South Wales, these animals could repopu late Tasmania if the wild population is wiped out. Schuster found seven distinct populations of devils, and says individuals from each must be collected to preserve genetic diversity. Unfortunately, data on where the animals were found suggests they have not been. Michael Marsh all •

Technology Management

I I

•I I •I I •

Educational Affiliate

CISCO

...... - -,_._,

. . .,..

I

••• •

-

ahead

... www.openuniversity.eo.uk/set ... 0845 300 8846

Quote: GAMAGL

INSPIRING LEARNING The Open Universi ty is incorpora ted by Royal Charter (RC 000391). an exempt charity in England and Wales and a charity registered in Scotland (S C038302).

Zj uly 2011 1NewScientist 111

THIS WEEK

One step closer to a nuclear timekeeper different. Instead of relying on light waves emitted by elect rons, WHY would anyone want to build it would use radiation emitted a super-precise clock in the hope when the nucleus is excited to that its tick drifts as t ime goes by? a high energy state, and then That's what is driving a team that drops into a lower energy state . is trying to build the first nuclear "All the electrons are going to clock, with a tick based on the sit in exactly the same place as antics of an atomic nucleus. They they normally sit," says Alex reason that the behaviour of the Kuzmich of the Georgia Institute clock could show whether certain of'Technology in Atlanta. "It's forces of nature fluctuate in a way the nucleus that's going to make that is predicted by some exotic a t ransit ion." theories of physics. The trouble is that most such transitions within th e nucleus The most accurate clocks we have are the so-called atomic emit high-energy X-rays or clocks. They exploit the fact that gamma rays, and these are tough an atom of caesium, or some to work with. An exception is other elem ent, emits visible thorium-229, an isotope light or microwaves when one produced in nuclear reactors of its electrons drops from a that has three fewer neutrons high energy state to a lower one. than the only naturally occurring The frequency of these emissions isotope, thorium-232. Its nucleus are so precisely predictable that is predicted to emit and absorb it can act like the t ick of a highly ultraviolet light. accurate clock. Atomic clocks As a first step towards building provide the super-accurate t iming a nuclear clock, Kuzm ich and needed for GPS satellites and to his colleagues have recorded the define the length of a second. ligh t given off by excited electrons in thorium-229 ions. The team A nuclear clock would be David Sh iga

LASERS COULD HELP BUILD A NUCLEAR CLOCK If nuclear clocks are possible, what about nuclear lasers? Thorium could be the key to building those too. Lasers have been made from a wide variety of materials. To date, they all work by exciting electrons that are either floating freely or in atoms, prompting the emission of a burst

crystals made mostly of lithium, calcium, aluminium and fluorine, with a sprinkling of thorium. Recent experiments suggest the electrons in this material will not interfere with the propagation of light emitted by thorium nuclei (Physical Review Letters, DOl: 10.1103/PhysRevlett.

of light. In atoms of the isotope thorium-229, the energy levels in the nucleus are arranged in such a way

106.162501).1n other materials, this effect would make a nuclear laser fizzle.

that the nucleus could also be made to emit ultraviolet light (see main story). Eugene Tkalya of the Institute

Though conventional lasers that emit UV light already exist , Tkalya say s that thorium lasers could form

of Nuclear Physics at Moscow State University in Russia suggest s making a thorium laser by firing

the light source in a nuclear thorium clock, and help us uncover the properties and behaviour of the

conventional ultraviolet lasers at

thorium-229 nucleus's excited state.

12 1NewScientist 12 July 2011

What makes tho rium tick?

fired a laser at a solid thoriu m-229 approach. He and his colleagues target in a vacuum chamber. This plan to hit a thorium-229 target stripped electrons from some of using light from a particle the m aterial, and vaporised it. accelerator, which can be more A second set oflasers then slowed easily tuned across a wide range and cooled this ion vapour, while of wavelengths than a laser. magnet ic fields kept the ions A nuclear clock could be used from hitting the chamber walls. to test whether the strength of A th ird laser th en excited the elect rons in these trapped ions. "The electrons are going The team was able to record the to sit in the same place as normal. lt's the nucleus light given off as th e elect rons in individual ion s dropped to that will make a transition" a lower energy state (Physical Review Letters, DOl: 10.1103/ the fundam ental forces of nature PhysRevLett .106.223001). changes over time. Some theories, To turn th is set-up into a including string th eory, predict nuclear clock, the team now needs that they should drift, and there to hit upon the precise frequency are some tentat ive hints of such oflight needed to excite the changes from astronomical thorium-229 nuclei - and observe measurements. the light emitted when it drops The frequencies of radiation back in energy. "If one of the ions emitted by an atomic clock makes this nuclear transition, are closely tied to a parameter we should be able to observe it called alpha, which governs the righ t away," says Kuzmich. Th is strength of the electrom agnetic will require painstakingly firing force. By contrast, the frequency lasers of different frequencies of a nuclear clock depends on at the trapped ions, watching for the strength of the strong nuclear when they emit light. force. So if the relative strength of these forces changes, it would The team's results are "really exciting" and "a huge step" show up as a divergen ce in the towards m aking a nuclear clock, time kept by a nuclear clock says Eric Hudson of the University compared with an atomic clock, of California, Los Angeles, who a tech nique that could be the is not a member of the team and most sensitive yet for seeing is working on an alternative this effect. •

FINANCIAL TIMES Gldeon Ractunan What to expect when China

Core competence lmprov~ the &Jobal regula ben of

becomes No.l

r '

Geithner warns on

light-touch oversight

Lut updated: 425pm Global martlet m11p

The US Treasury secretary warm. 0\"Cl"'iWS

.....

markets against

unden:utting Amencan financial regutaclons, Ul"gU\Jt them to avoid the 'tr.rgk' ""lmPlt> M't b)' lht' UK

c

__I*' c

..._

I! i t -

hi

C

r ce

¥ M .i

··- --·- .....

I j

j

THIS WEEK

Stress is inherited via faulty DNA zip Andy Coghlan

st ressed celL If that cell h appens to be an egg or sperm, the altered chromatin will end u p in every cell in any offspring. Ishii pinpointed this mechanism by altering fruit flies to give them a gen e for red eyes. The gene was positioned so that it would be active on ly if chromatin was unzipped, m aking it easy to spot whether ATF-2 had been detached an d th e ch romatin h ad been altered. Ishii put one generation of mutated fruit flies under stress by heating the eggs from which they hatched, or exposing the eggs to salty water. After they had m atured t o adulthood, he m ated them with healthy flies and found that the unzipped ch rom at in and red eyes - passed to the second, but not third generation. But wh en Ishii put both th e first and the second generations under st ress, the effects were

MUTANT fruit flies h ave helped solve one of the biggest puzzles in genetics: how the damaging effects of stress can pass down th e generations to children and grandchildren. Stress is thought to cause "epigenetic" changes to genes, which do not alter the sequence of their DNA but instead leave chemical marks that dictate how active genes are. If mice are st ressed for two weeks after birth, for example, their offspring will show signs of depression and anxiety, despite enjoying the Poorer health for grand kids too usual levels of maternal care. There is mounting evidence th at common health problems including diabetes, obesity, mental illness and even feeling fear could be the result of stress on parents and grandparent s. Until now no one has been able to identify changes in inherited "Once the protein is DNA that might explain h ow detached, the chromatin these effects are passed on. structure opens, activating Shunsuke Ishii at the Riken genes that were hidden" Tsukuba Inst itute in Ibaraki, Japan, and colleagues have now identified a plausible process. "We more prolonged, influencing not believe we can convince many just one but three subsequent sceptics by clarifying the generations (Cell, DOl: 10.1016/ mech anism," says Ishii. j.celL2011 .05.029 ). His team discovered that He says th at mammals have a chemical or environmental counterpart to ATF-2 called ATF-7. What do octopus and mammal eyes tell us stress detaches a protein called Last year, his team found t hat activat ing transcription factor 2 psychological stress could alt er about repeated patterns in evolution? (ATF-2) from chromat in, the ATF-7 in mice, leading to changes What about hummingbirds and sunbirds? densely packed DNA th at makes in chromatin. Ishii's team st ill To find out visit www.mapoflife.org and up chromosomes. needs to do experiment s to see if e xplore amazing cases of biological converge nce ATF-2 behaves as a kind of these changes are heritable. zipper, keeping the ch romatin "What's really exciting is from througho ut the living world. tightly bound. Once it is detached, that this study shows a clear .IIJIII UNTVEHSITY Of jOll:" TEM PU:TO~ FO~D.HIOii the chromatin structure opens, molecular mech anism that V CAMBR I DG E ,.,..,.,.,, ,..,. •mn-, ·m "''"'"'''" facebool< WORDPRESS activating genes th at would responds to stress," says Moshe normally stay hidden. Szyf, who researches the Crucially, the unzipped implications of epigenetics chrom at in is inherited by all for cancer therapy at McGill University in Montreal, Canada. • descendants of the original

AP OF LIFE

CONVERGENT EVOLUTION ONLINE

www.mapoflife.org

p: lnd

14 1NewScientist IZJuly 2011

.~~

f>"

For daily news stories, visit newscientist.com/news

If you spot an illusion do you ever ask why? THOSE who find optical illusions easy to solve might be less inclined to ask themselves why. lt seems the human brain may have a trade-off between processing visual information and introspection. Chen Song and her colleagues at University College London found last year that people with more grey matter in the primary visual cortex were better at solving visual illusions. The team has now looked for size differences elsewhere in the brain that correlate with variation in the visual cortex. They used a functional MRI scanner to build a map of the primary visual cortex of 30 volunteers while also capturing a structural image of their brains. Running the images through a

SSE_Advert_exhibrtion.Jand..242x 142mm.indd 1

"

:::>

~

:!' z :z

i

;5 u "' iX

if

_ _, Baffling for some computer, Song was surprised to find a relationship between the primary visual cortex and a region at the front of the brain called the anterior prefrontal cortex (aPFC). When people have a bigger anterior prefrontal cortex, they have a smaller visual cortex, and vice versa:· she says Uournal of Neuroscience, DOl: 10.1523/jneu rosci.0308-11.2011). Previous research has shown

that the size of the aPFC is linked to introspection - individuals with more grey matter in this brain region are better able to assess whether they made the right decision. Song~ study suggests that more introspective individuals forego finer aspects of visual perception. The team will now carry out behavioural studies to find out if this is the case. What could be behind this

relationship? Animal studies have shown t hat some genes involved in brain development are expressed at differing levels along the anteriorposterior axis of the brain;· says Song. Those differences might be most stark when comparing structures at opposite ends of the cortex - such as the aPFC and primary visual cortex. Elliot Freeman at City University in London agrees that the results are a surprise. But bigger is not necessarily better in terms of brain power," he says. Despite evidence that a large aPFC might be linked to better introspection, a small aPFC might be beneficial too, Freeman says. lt might be better to have fewer synaptic connections for more focused and coherent decision making." However, more neurons in the visual cortex might boost resolution in visual processing, Freeman adds. A brain with more visual volume and less frontal volume might actually work better." j essica Hamzelou •

2116111 13:07:()6

2 July 2011 1NewScientist 115

IN BRIEF The hidden stress of ecotourism ECOTOURISTS are doing monkeys n o favours by sharing their picnic with them. Wildlife tourism is already thought to stress m any species. To study its effect on Barbary macaques (M acaca sy lvan us) in the Moroccan Atlas m ountains, Laetitia Marechal and Stuart Semple of the University of Roehampton, London, recorded levels of glucocorticoid hormonesan indicator of stress - in the m onkeys' faeces. Th ey also monitored rates of self-scratching, which relates to anxiety. The researchers found that even something as seemingly innocuous as taking a ph oto or feeding the m acaques increased the likelihood of anxiety, while aggression from tourists pushed them int o full-blown stress (Biological Conservation, DOl : gauged the birds' sense of syntax by playing jumbled

Finches' tweets knock humans off their perch

"ungrammat ical" re mixes of finch songs to the birds and measuring the response calls.

HUMANS may not be the only species to have rules of syntax dictating how words can and cannot be put

One way they did this was by playing unfamiliar songs repeatedly until the birds got used to the m and stopped overreacting. They then jumbled up syllables

together. The songs of Bengal finches appear to have similar grammatical rules. "Songbirds have a spontaneous ability to process syntactic structures in thei r songs;'

w it hin each song and replayed these versions to t he birds. The birds reacted to only one of the f our jumbled versions, as if they noticed it violated some rule of

says Kentaro Abe of Kyot o University, j apan, who has been putting the birds' grammatical abilities to the t est. In the wild, Bengal finches call back vigorously when

grammar, w hereas the other t hree remixes didn't. Almost 90 per cent of t he birds tested responded in this way (Nature Neuroscience, DOl: 10.1038/nn.2869).

they hear unfamiliar songs, usually f rom intruding finches. In t he lab, Abe and colleague Dai Watanabe of the japan Science and Technology Agency in Saitam a

"This indicates the existence of a specif ic rule in t he sequential orderings of syllables in their songs, shared within the social community," Abe says.

Famous black hole reveals vital statistics SOME black holes keep a t ight hold on everything, even their own vital statistics. Now Cygnus X-1, the first black hole discovered, has divulged its distance from Earth and in turn its weight and that it was born spinning. Cygnus X-1 was identified as a likely black hole in 1972, but its distance from Earth has been maddeningly difficult to pin down. This in turn h as made 16 1NewScientist I ZJuly 2011

it hard to determine basic properties like its mass and spin. Mark Reid of the HarvardSrnithsonian Center for Astrophysics in Cambridge, Massach usetts, and colleagues used the Very Long Baseline Array of radio telescopes spanning the US to measure the object's parallax - tiny shifts in its apparent position due to Earth's motion around the sun. Based

on the size of the sh ifts, Cygnus X-1 is 6ooo light years away, give or take a few hundred light years, the team reports (arxiv.org/ abs/1106.3688). Combining this measurement with oth er information revealed a rapid spin rate and the m ass of the black hole to be 14.8 times the sun's (arxiv.org/abs/uo6,368g). It was likely born in a spin as it would not have had enough time to "spin up'' by stealing gas from its companion star.

10.1016/ j.biocon.2011.0 5.010). Such studies are vital to help establish guidelines, says Semple.

Cream slows snake venom's invasion DEADLYsnake-bite venom could be slowed on it s way into the blood by a cream applied to the bite site, giving victim s time to seek help. Snake bites penet rate tissue, not blood vessels, so most of the toxins enter the blood via the lymphatic system. To slow this journey, Dirk van Helden at the University of Newcastle at Callaghan, Australia, and colleagues applied nitric oxide cream - which stops the pum ping of the lymphatic system - to mice injected with venom. Th e cream increased th e time it took the venom to reach the blood supply from 65 to g6 minutes (Nature Medicine, DOl: 10.1038/n m .2382). This would buy bite victims around so per cent m ore time to seek t reatment, says van Helden.

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

Python genes get Yeast points way to making old cells young again frantic after meals CHILDREN typically h ave t he they acquire clumps of p roteins lifespan (Science, DOl: 10.1126/ A BURMESE python that has just eaten a goat may look like it's resting, but on the inside it's frantic. The python's digestion switches on an unusually large number of genes. Pythons eat large meals very infrequently. To conserve energy between meals, they mothball their innards, substantially shrinking most of their internal organs. Then, after a meal, their intestines more than double in mass, and the heart and kidneys increase by half. This involves a huge amount of genetic turmoil. To find out just how much, Todd Castoe and colleagues at the University of Colorado at Denver measured gene activity in the organs of Burmese pythons,

same life expectancy at birth, regardless of whether their father is 20 years old or 8o. This must mean that the man's reproductive cells somehow reset their clocks, but how th ey do this h as been a mystery. Now a gene t hat reverses ageing effects in yeast is providing some clues. Under stressful conditions yeast cells forgo asexual reproduction an d sp lit into four spores, each containing half the chromosomes of a typical cell, like human eggs and sperm. As the cells get older,

and extra p ieces of DNA, but when Angelika Amon at the Massachusett s Inst itute of Technology and colleagues tracked spores from old an d young yeast cells they found th at such abnormalities disappeared, meaning all spores h ad the same lifesp an. Clumped protein seems to be cleared through autophagy, in wh ich the cell "eats" itself. During sporulation, a gene called NDT8o was expressed. What's more, switching on NDT8o in ageing cells doubled their

science.1204349). The closest relative ofNDT8o in mammals is p53, a gene th at regulates cell cycles. "We may h ave found a way to rejuvenate cells and erase ageing m arkers," says Am on. The paper is "provocat ive", says Michal Jazwinski at Tulane Un iversity in New Orleans, Louisiana: "People have attempted to examine what rejuvenates gametes for some time.lt looks like NDT8o is playing an important role - it narrows down th e t erritory to be examined."

Jet-setting worm has first-class DNA

Python mo/urus bivittotus, before and immediately after meals. About 1800 dormant genes switched on within 24 hours of a meal, they reported last week at the Society for the Study of Evolution meeting in Norman, Oklahoma. Similar activation also occurs in the liver, kidney and intestines, they say. This is a staggering change: previously only a few dozen and up to a few hundred genes had been seen to change to cope with new conditions. Even the transition from an unfertilised egg to a 4-celled embryo - one of the biggest changes in an organism's life involves fewer than 3000 genes, a previous study has found .

YOU would probably expect worm s in California and France to h ave different gen es, even within one species. Not so for a stretch of ch romosome from the laboratory workhorse Caenorhabditis elegans.

Joshua Shapiro ofPrinceton Un iversity and his colleagues compared about 40,000 genetic markers from 97 wild strains collected around the world. Those on chromosome 5 were virtually identical in the vast m ajority of worms, they reported last week at a meeting of the Society for the Study of Evolu tion in Norman, Oklahoma. Such a pattern can only be the result of strong natural selection for a gene, which would have caused all neighbouring genes to be selected as well. Based on the size of this "selective sweep", Shapiro calculates that the favoured gene variant arose 100 to 200 years ago and has since spread across the world, m ost likely by hitch-hiking with human migrat ions. ''This is the first time we h ave seen a natural selective sweep of this much DNA," says Dee Denver at Oregon State Un iversity in Corvallis.

'Broken' toy shows infants' rationality INFANTS can work out where the

17 infants soon turned to another toy.

fault lies when a toy fails to work. Hyowon Gweon at Massachusetts

In a separate trial, one adult's button presses always worked, while the second adult's always failed.

Institute of Technology tested 16-month-olds' reasoning using a toy that could be worked by pressing a button. Two adults showed an infant how to play with the toy, but both could make it work correctly just one time in two tries. They then passed the toy to the child- exceptthat now, the button was no longer active. The infants appeared able to work outthat the toy was faulty, given that both adults had previously had trouble making it work: 12 out of

When the toy didn't work for the infant, they appeared to reason they were doing something wrong, like the unsuccessful adult -13 out of 19 children passed the toy to their parents for help (Science, DOl: 10.1126/science.1204493). Sara Cordes at Boston College in Massachusetts says the findings fit with current ideas about child cognition: "Infants are little adults when it comes to problem solving."

2 July 20111 NewScientist 117

N=f(f,:n,.·£·h·fc ·I

~it= ik.r"W ;r,. ___

£,v'-H

You don't need to be a scientist to be an expert.

New Scientist delivers the highest quality scientific content from the world's most reputable sources in a comprehensive and easy to digest format.

With our monthly Instant Expert series we'll guide you through Astrobiology, Mass Extinctions, Dark Matter and much more. Your weekly issue will keep you up-to-date with the latest space news, technological developments, and breakthroughs in healthcare and environmental science. Get all of this, together with access to our online archive for less than two dollars per issue.

To save over 60°/o off the cover price, subscribe at newscientist.com/s/5305

TECHNOLOGY

For more technology stories, v isit newscientist.com/technology

including researchers at the University ofLiverpool in the UK and the Swiss Federal Institute ofTechnology in Lausanne (EPFL) - aim to establish rules for autonomous flight, including sensing, flocking, control and simulation, and to develop simple user interfaces for pilots. Accurate sensing will be at the heart of it all. At EPFL, Dario

"lt is now a question of when we'll get personal aerial vehicles, not if we'll get them" Floreano's team is investigat ing what mix of anti-collision sensors Who n eed s a pilot's licence? PAVs might need. He envisages each craft pinging radio signals to all the others and measuring the signals' return time to keep a safe distance. "It will work even when GPS is not available," Floreano says, adding that such a system is Technology to avoid mid-air collisions will be vital when now being test ed on a swarm of we/ve all got our own personal helicopter... 10 four-rotor robots, as part of the EC-funded Swarmanoid project. PAVs is not quite so fan tastic? Floreano's team has already thanks to recent developments Paul Marks Witness Terrafugia, he says, a in helicopter drones. developed image sensors with a WHO wouldn't like to have their spin-off from the Massachusetts wraparound view like that of an Despite Terrafugia's progress, own personal flying machine Institute of Technology, based MyCopter is only focusing on insect's compound eye. If visibility tucked away in the garage? It's helicopter-style PAVs because they is poor, acoustic sensors may do in Woburn. The firm hopes next year to launch the Transition, a won't need a runway: you can take the trick. "You can work out the a nice thought, if perhaps a little far-fetched. off from a parking space. "We are speed and direction of approaching lightweight propeller-powered Be that as it may, the European aircraft that can land on a runway, looking at vertical take-off and aircraft from the sound they Commission is taking the landing because we don't want make," Floreano says. Radar and fold its wings and be driven away prospect seriously. And it is like a car- although not everything to use airports for air commuting. laser-based sensors (lidar) will already worried about how has gone to plan (see "Flying cars: There's a problem, however: we also be tested. The EPFL team squadrons of non-expert pilots don't expect the average car driver hopes to build a demonstrat ion a chequered history"). What's are going to cope with this threemore, technologies for lofting to know how to fly a helicopter." sensor array by 2014. dimensional freedom. Will air and propelling small aircraft To begin to address this, PA Vs might not be entirely hogs cause mid-air collisions? are maturing fast, BU!thoff says, MyCopter project members autonom ous, says BU!thoff. You That's why the EC has kicked should be able to override them, off a €4.3 million research project, just as drivers can ignore satnav directions in a car, he says. called MyCopter, that aims to ensure "personal aerial vehicles" Fortunately, MyCopter will (PAVs) can fly automatically in neat, That flying cars are a long-held dream but never went into mass production. have other applications before is evident from the patent record: NowTerrafugia, an MIT spin-off, we eventually take delivery of well-spaced "swarms" by sensing one was patented in France three is hoping Its Transition flying car will the other vehicles around them. our first personal helicopter: the "It is now a question of when months before the Wright brothers' triumph. lt is built from lightweight flocking algorithms developed we'll get personal aerial vehicles, first powered flight in 1903. But carbon fibre composites and has a will make it easier for drones to tly not if we'll get them," claims in civilian airspace, and simpler success has eluded all comers. light. powerful engine. But after a successful test flight in March 2009 Heinrich Billthoff of the Max In 1917, the Wrights' arch-rival user interfaces could make it Planck Institute for Biological Glenn Curtiss built a flying car that problems with suppliers have slowed easier to fly them. As for replacing progress: a demo flight this year has would only hop. In 1956 Moulton cars, th e technology's there, says Cybernetics in Tiibingen, Taylor's Aerocar took to the US skies. been postponed to 2012. Germany, who heads the project. Biilthoff. "Making it affordable is Why does he think the idea of another question." •

out o trou.....,., e

Flying cars: a chequered history

Zj uly 20111 NewScientist 119

TECHNOLOGY

e . . . . owero

ou

Severely disabled people can control their environment without invasive implants Duncan Graham-Rowe TWO friends meet in a bar in the online environment Second Life to chat about their latest tweets and favourite TV shows. Nothing unusual in that- except that both of them have Lou Gehrig's disease, otherwise known as amyotrophic lateral sclerosis (ALS), and it has left them so severely paralysed that they can only move their eyes. These Second Lifers are just two of more than so severely disabled people who have been trying out a sophisticated new brain-computer interface (BCI). Second Life has been controlled using BCis before, but only to a very rudimentary level. The new interface, developed by medical engineering company G.Tec of Schiedlberg, Austria, lets users freely explore 20 I NewScientist I2July 2011

Second Life's virtual world and control their avatar within it. It can be used to give people control over their real-world environment too: opening and closing doors, controlling the TV, lights, thermostat and intercom,

~

answering the phone, or even publishing Twitter posts. The system was developed as part of a pan-European project called Smart Homes for All, and is the first time the latest BCI technology h as been combined with smart-home technology and online gaming. It uses electroencephalograph (EEG) caps to pick up brain signals, which

Brain control Detecting peopl e~ brainwaves gives them control over their environment

A screen displays 40 or

more icons which flash in random order. To activate a command the user focuses their attention on the appropriate icon

When the icon flashes, an involuntary change in the brainwaves (P300 spike) occurs. Software identifies the icon from the timing of the spike, and sends an appropriate command to a controller

it translates into commands that are relayed to controllers in the building, or to navigate and communicate within Second Life and Twitter. In the past, one of the problems with BCis has been their reliability, and they have tended to be limited in the number offunctions that can be controlled at once, says John Gan of the BCI group at the University of Essex, UK. Like most BCI systems, G.Tec's interface exploits an involuntary increase in a brain signal called P300 that occurs in response to an unexpected event. To activate a command, the user focuses their attention on the corresponding icon on a screen, such as "Lights On", while the EEG cap records their P300. The icons are flashed randomly, one at a time, and it is possible to tell which icon they are looking at by correlating a spike in the P300 with the timing of when that icon flashes, says Guenter Edlinger, G.Tec's CEO. He will be presenting the system at the Human and Computer Interact ion International conference in Orlando, Florida, this month. G.Tec's system works better, the more functions are added. That is because when there are more icons on the screen, it comes as a bigger surprise when the target icon flashes, creating a stronger P300 response. More than 40 icons can be displayed at once and submenus make it possible to add even more options. G.Tec's system has been tested at the Santa Lucia Foundation Hospital in Rome, Italy. "BC Is are definitely beginning to make the transition out of the lab," says Ricardo Chavarriaga, a BCI researcher at the Swiss Federal Institute ofTechnology in Lausanne. G.Tec says it is working on adding wheelchair control as a function, to help give users more mobility. "The point is that they can start making their own decisions," says Edlinger. •

For more technology stories, visit newscientist.com/technology

Robo-snapper learns how to take the perfect photo PAPARAZZI could soon be fighting for their jobs with robots that can take aesthetically pleasing photos. To create such a robot, Raghudeep Gad de, a computer scientist at the International Institute of Information Technology in Hydra bad, India, turned to a humanoid robot called NAO that is equipped with a head-mounted camera. He and his team have programmed NAO to obey two simple photographic guidelines known as the rule of thirds and the golden ratio. The former states that an image should be divided into three, both vert.ically and horizontally, with interesting features placed where the dividing lines cross. The latter suggests the horizon line should divide a photo into two rectang les with the larger being 1.62 times the size of the smaller - the golden ratio. The robot is also programmed to assess the quality of its photos by rating focus, lighting and colour. The researchers taught it what makes a great photo by analysing the top and bott om 10 per cent of 60,000 images from a website hosting a photography contest, as rated by humans. Armed with this knowledge, the robot can take photos when told to, then determine their quality. If the image scores below a certain quality threshold, the robot automatically makes another attempt. lt improves

on the first shot by working out the photo's deviation from t he guidelines and making the appropriate correction to its camera's orientation. Gadde, who w ill presentthe research at an artif icial intelligence conference in Barcelona, Spain, t his mont h, says t his makes the system very flexible. "Earlier photographer robot systems are predominantly limited to capturing photographs of humans," he says, because they rely on face or skin-colour detection. "Our approach is generic and does not rely on t he subject of the

" The robot obeys two photographic guidelines and then assesses the quality of the photos" image being captured." Bill Smart of Washington University in St Louis, who has also built a robot photographer, says the approach is an improvement on previous attempts. But robots still can't match human photographers because t hey can't recognise point s of int erest.• he adds. "Good compositions in photographs have interesting things in them, and there's no such thing as an 'interesting thing detector'." Gadde's system could be used to take formulaic photos t hat all follow certain ru les, such as actors' headshot s, he says. jacobAron •

Could a robot do it better?

2 July 20111 NewScientist 121

TECHNOLOGY combine two or more photographs photo they want to post online. The photo then goes through to create another very realistica "dewarping" stage, in which looking one that looks like it was taken from an arbitrary straight lines like walls and kerb viewpoint," explains Schaffer. angles are corrected for the new The images can come from AN IMAGE processing system that Peter Schaffer and Djamila Aouada point of view, and "hole filling", obscures the position from which at the University ofLuxembourg more than one source: what's in which nearby pixels are copied photographs are taken could help to find a way of disguising the important is that they are taken to fill in gaps in the image created protesters in repressive regimes photographer's viewpoint. at around the same time of a because some original elements were obscured. The result is pretty escape arrest- and give journalists Their method is to use graphics reasonably static scene from different viewing angles. Software convincing, says Schaffer. "There "plausible deniability" over the processors to artificially create provenance ofleaked photos. photos taken from a perspective then examines the pictures and are some image artefacts but they where there was no photographer. generates a 3D "depth map" of are acceptable," he says (arxiv.org/ The technology was conceived in September 2007, when the "We use a computer-vision the scene. Next, the user chooses abs/1106.2696). The team intends Burmese junta began arresting technique called view synthesis to an arbitrary viewing angle for a to make the software open source. Matthias Zwicker, a graphics people who had taken photos of the violence meted out by police ~ engineer at the University of « against pro-democracy protesters, ~ Bern in Switzerland, thinks the ""~ technology is on the right track. many of whom were monks. "Burmese government agents "Anonymising the photographer video-recorded the protests and ~ could be a crucial step in protecting analysed the footage to identify ~ the source of contentious material. "'~ I'm sure this computer-vision people with cameras," says ::> ~ technology will evolve into a security engineer Shishir Nagaraja of the Indraprastha Institute of ~ valuable tool:' Information Technology in Delhi, ~z Schaffer's team knows it is g0 entering an arms race of sorts: India. By checking the perspective of pictures subsequently published ~ even consumer-level imaging tools on the internet, the agents worked "' could help oppressive regimes. For out who was responsible for them. instance, University ofWashington If a photographer's "location and Google researchers last week privacy" is not protected, their unveiled software that can identify personal safety is at risk, Nagaraja as pecific person in every picture • says. This inspired him and in a large set of photos on a website computer-vision specialists lt's all about points of view like Flickr.com. Paul Marks •

Protecting protestors with photos that never existed

t 2 July 20111 NewScientist 135

New reality goggles Augmented-reality glasses already make it possible to visualise what was once unseeable, by overlaying graphics onto your field of view. Add the right sensors and apps, and here are some of the things you might one day see through those specs In Rio de Janeiro and Sao Paolo, police officers can decide whether someone is a criminal just by looking at them. Their glasses scan the features of a face, and match them against a database of criminal mugshots. A red light blinks if there's a match. So far, tech like this is available mainly to governments, but that won't last. Facebook has recently turned on face recognition for its automatic photo tagging. AR software will likely soon interface with social networks, so that you will never again forget a name at a party- but anonymity in a crowd may become a thing of the past.

The recent E. coli outbreak in Germany shows how important it can be to know exactly what you are eating. One way to analyse food could be via "hyperspectral" imaging, which uses special sensors to image far more of the electromagnetic spectrum than the small window visible light normally allows. Bacteria and spoilt food give off specific signatures. And the proper sensors can identify bacteria, insect repellent. mysterious smells or contaminants on the chopping board. "it's like doing CSI on the fly," says Paul Lucey, who works on hyperspectral vision at the University of Hawaii.

Thad Starner at Georgia Institute of Technology in Atlanta wears a small device he has built that looks like a monocle. lt can retrieve video, audio or text snippets of past conversations with people he has spoken with, and even provide real-time links between past chats and topics he is currently discussing. In principle, it could also be used to view other people's conversations, if that person allowed them to be shared.

The US military has built a radar-imaging device that can see through walls to capture 30 images of people and objects beyond.ln similar vein, Yaser Sheikh of Carnegie Mellon University in Pittsburgh, Pennsylvania, is building an augmented-reality system for cars that lets drivers see round a blind corner. Taking video from a camera focused on the part of the road hidden from t he driver, it distorts the image so that it appears on the AR display, letting the driver essentially see through the obstacle.

You could use microphones and speech-recognition technology to convert the voice of someone you are conversing with to scrolling, real time subtitles. Thad Starner uses a basic version of this technology on his wearable set. A more sophisticated app would include subtitles t hat appear under specific people in the form of speech bubbles. 361 NewScientist I2 July 2011

equipped with Picard's technology were learning extra social skills. Baron-Cohen says the wearers retained some ability to read emotions accurately after they removed the glasses. Such enhancements for the rest of the population might increase emotional intelligence through the generations. But giving people unfettered access to each other's emotions has dangers too, Baron-Cohen warns. 'The ability to read someone's emotions doesn't necessarily come with empathy," he says. Pi card is keen to stress that her technologies should not be used covertly, and that people should always be asked whether they wish to use them, rather than being forced to do so. Use of her gloves is by their very nature voluntary- you have to choose to wear them - but remote heart-rate monitoring does not require consent. Pentland takes a similar view on the need for privacy. Data generated by the sociometric badge data should only be visible to an employee, he says, and not be shared with an employer without the employee's consent.

"When I slipped on the glove, I got a taste of how it can feel to have my most private thoughts exposed" I got a taste of how it can feel to have my most private thoughts exposed when I slipped on one of Picard's Q Sensor gloves to measure my skin conductance. A purple neoprene band pressed two electrodes into the palm of my hand, measuring subtle moisture changes on my skin when my stress levels changed. I watched a trace on Picard's screen, reminiscent of a seismogram. "OK, now just think about anything that will make your heart beat faster," she told me. I immediately suppressed my first intrusive thought because I found it just too embarrassing - and stared in horror as the scribble nevertheless exploded into a vertical spike. "Wow," Pi card said, her eyes widening. "What was that?" I felt my face go beetroot red. Picard considered my reaction for a second. She didn't need a headset to know that if I aired this particular thought it might make our conversation rather awkward. "Never mind," she said, "I don't want to know." • Sally Adee is a technology features editor at New Scientist

DIF FERENT TYPESOF INTELLIGENCE Conside r the engineertg superio r spatial intelligence and the lawyer(g command of words and you have to wonde r whethe r there are differe nt types of intelligence. This quest ion was debated ferociously during the early decades of the 20th century. Charles Spearman, on one side, defend ed the omnipot ence of his genera l factor of int elligence, g. On t he other, Louis Thursto ne argued for seven primary abilitie s", includin g verbal comprehension (in which fema les excel) and spatial visualisati on (in which males excel). Thursto ne eventu ally conceded that all his primary abilitie s were suffuse d with the same g factor, while Spearman came t o accept t hat t here are multipl e subsidiary abilit ies in addit ion to g on which individu als differ. This one-plus-many resolut ion was not w idely accepte d unti1 1993, howev er. lt was then that American psychologist John B. Carroll published his three stratum theory" based on a monum ental reanaly sis of all factor analysis studies of intelligence (see Oiagram , right). At t he top is a single universal ability, g. Below this indivisi ble g are eight broad abilities , all composed mostly of g but each also containing a differe nt additiv e" that boosts performance in some broad domain such as visual percept ion or processing speed. These in t urn cont ribute t o dozens of narrow er abilities , each a complex compos ite of g, plus addit ives from the second level, toget her with life experiences and specialised aptit udes such as spatial scanning. This structu re makes sense of the many differen ces in ability bet ween individu als w ithout contrad icting the dominance of g. For example, an excelle nt engine er might have exceptional visuospatial percep tion togeth er with training to develo p special ist abilities. but above all a high standin g on the g factor. The one-plus-many idea also exposes the implausibility of multipl eintellige nce theo ries eagerly adopte d by educat ors in the 1980 s, w hich claimed that by tailorin g lessons to suit the individ ual(g specific streng th- visual. tactile or whatev er- all children can be highly intelligent in some way. ii I NewScientist 12 July 2011

The "three stratum theory" of intelligence recognises that there is a single general cognitiv e ability, g. with added input Genera l from a range of broad Intelligence and narrow abilities factor Broad abilitie s nUid mte io·· · e '- 7sta 1sed inh:: 1 \lence Processing speed Broad retrieval ability Broad cogmt1ve speed Broad visual perception Broad auditory percept on General and

Narrow abilitie s 64 specialised aptitudes 01 s il s that each relates to a specific broad ability

WHAT DO IQ TESTS MEASURE? A century ago, British psycho logist Charles SpE!anna' observed that individu als who do well on one mnta test tend to do well on all of them, no matter how differe nt the testsOiims, format or conten t. So, for example, your performance on a test of verbal ability predict s your score on one of mathem atical aptitud e, and vice versa. Spearman reasoned that all tests must therefo re tap into some deeper, general ability and he invente d a statisti cal method called factor analysis to extract this common factor from the web of positive correlations among tests. This showed that tests mostly measure the very same thing, which he labelled the genera l factor of intellig ence or g factor". In essence, g equates to an individual!!) ability to deal with cogniti ve comple xity. Spearmanl!) discovery lay neglec ted in the US until the 1970s, when psychologist Arthur jensen began system atically testing compe ting ideas about g. Might g be a mere artefac t of factor analysis? No, it lines up with diverse feature s of the brain, from relative size to processing speed. Might g be a cultura l artefact, just reflect.i ng the way people think in wester n societies? No, in all human groups - and in other species too most cogniti ve variatio n comes from variatio n in g. jensenl!) analyses t ransfor med the study of intellig ence, but while the existen ce of g is now genera lly accepted, it is still difficu lt to pin down. Like gravity, we cannot observe it directly, so must understand it from its effects. At t he behavioural level, g operate s as an indivisi ble force- a proficie ncy at mental ly manipu lating informa tion, which underg irds learnin g, reasoning, and spottin g and solving ~ problems in any domain. At the physiological level, ~ differen ces in g probab ly reflect differen ces in the ~ brain!!) overall efficien cy or integri ty. The genetic roots ~ of g are even more dispersed, probab ly emerging from

the joint actions of hundre ds if not thousa nds of genes, themse lves responding to differe nt environ ments. Higher g is a useful tool, but not a virtue. lt is especially handy when life tasks are complex, as they often are in school and work. 1t is also broadly protective of health and well -being, being associated with lower rates of health-damaging behaviour, chronic illness, post-t raumat ic stress disorder, Alzheim erl!) and premat ure death. Higher g helps an individu al get ahead socioeconomically but it has little connec tion with emotio nal well-be ing or happiness. Neithe r does it correlate with conscientiousness, which is a big factor in whethe r someone fulfils their intellec tual potenti al.

WHAT IS INTELLIGENCE? Intelligence matters to us. In surveys people rank it second only to good health. Women worldwide believe smarter men make better husband material. Entrepreneurs hawk brain-boosting games, foods, supplements and training programmes. And the media quickly broadcast any scientific study claiming to discover how we can make ourselves, or our children, smarter. Yet our keen private interest in intelligence is matched by a reluctance to acknowledge publicly that some people have more of it than others. Democratic people value social equality above all, so they mistrust anything that might generate or justify inequality- but intelligence is no more equally distributed in human populations than height is. This tension has led to rancorous controversy over intelligence and intelligence testing but it has also benefited the science by pushing it exceedingly hard. A century of clashes and stunning discoveries has upended assumptions and revealed some fascinating paradoxes. Intelligence is definitely not what most of us had imagined.

QUANTIFYING INTELLIGENCE

Alfred Binet invented the IQ test to identify those schoolchildren most in need of help

The first intelligence quotient (IQ) test was born of a desire to help the most vulnerable.ln 1904 the French

select talent from all social levels, but today their use can be considered

Ministry of Education commissioned psychologist Alfred Binetto find a practical way to identify children who would fail elementary school without special

contentious, partly because they do not find equal amounts of intelligence everywhere.

help. Binet assembled 30 short, objective questions on tasks such as naming an everyday object and identifying the heavier of two items. A child's

Nevertheless, intelligence testing continues because it has practical value. Many colleges, employers and

performance on these, he believed, would indicate whether their learning was "retarded" relative to their peers. His invention worked and its success spawned

the armed services still use paperand-pencil or computer-based

massive intelligence-testing programmes on both sides of the Atlantic. Organisations turned to IQ tests to screen large pools of applicants: military recruits for

intelligence tests to screen large groups of applicants. The gold standard, however, is the orally administered, one-on-one IQ test,

trainability, college applicants for academic potential and job applicants for employability and promotability. The tests were eagerly adopted at first as a way to

which requires little or no reading and writing. These include the StanfordBinet and Wechsler tests, which take between 30 and 90 minutes and combine scores from areas such as comprehension, vocabulary and

Average IQ score distri but ion by population

reasoning to give an overall IQ. These batteries are used to diagnose, treat

c 0

·;::;

or counsel children and adults who need personal or academic assistance. Ability testing is governed by detailed

10

:J

a. 0 a.

0 Q)

ethical standards and professionally administered tests must meet strict criteria including lack of cultural bias

01

2c

Q)

u ._ Q)

20%

0..

5%

70

5%

80

90

100 IQ score

110

120

130

and periodic updating. In fact, IQ tests are the most technically sophisticated of all psychological tests and undergo the most extensive quality checks before publication. 2 July 20111 NewScientist I iii

OLDERAND WISER The brain is a physical organ and no less subject than any other to ageing. illness and injury. The normal developmental trajectory is that aptitude at learning and reasoning- mental horsepower - increases quickly in youth. peaks in early adulthood, and then declines slowly thereafter and drops precipitously before death. The good news is that some important abilities resist the downturn. Some IQ researchers distinguish between tests of fluid intelligence (gF) and crystallised intelligence (gC). The first assess on -the-spot learning, reasoning and problem solving; the second assess the crystallised fruits of our previous intellectual endeavours, such as vocabulary in one's native language and broad cultural knowledge. During youth gF and gC rise in tandem, but they follow different trajectories thereafter. All gF abilities decline together, perhaps because the brain's processing speed slows down with age. However, most people's gC abilities remain near their personal peak into old age because they reside in the neural connections that gF has laid down over a lifetime of learning and practice. Of course, age-related memory loss will affect an individual's ability to recall, but exactly how this affects intelligence is not yet known. This has practical implications. On the positive side, robust levels of gC buffer the effects of declining gF. Older workers are generally less able to solve novel problems, but they can often compensate by calling

upon their larger stores of experience. knowledge and hard-won wisdom. But gC can also disguise declines in gF, with potentially hazardous results. For example. health problems in later life can present new cognitive challenges, such as complex treatments and medication regimes, which individuals with ample gC may appear to understand when actually they cannot cope. There are ways of slowing or reversing losses in cognitive function. The most effective discovered so far is physical exercise, which protects the brain by protecting the body's cardiovascular health. Mental exercise, often called brain training, is widely promoted, but it boosts only the particular skill that is practised its narrow impact mirroring that of educational interventions at other ages. Various drugs are being investigated for their value in staving off normal cognitive decline, but for now preventive maintenance is still the best bet- avoid smoking, drinking to excess, head injuries and the like.

Somatosensory

Word formation Auditory

·~ Behaviour, emotions, motivation

Language, comprehension

O~ct

naming

iv I New Scientist 12 July 2011

Vision

Volume of the cortex, the brain's grey matter, correlates with IQ

Overall size of the brain, relative to the body, correlates with IQ

Intelligence requires integration of sensory and other information

Visual processing

Learning and experience can increase the size of specific brain areas

High IQ is associated with faster mental processing speed

Volume of tissue linking the brain's hemispheres correlate s with IQ

WHAT MAKES SOMEONE SMART? Intelligence tests are calibrated so that, at each age, the IQ average score is 100 and 90 per cent of individuals score between IQ 75 and 125. The typical IQ difference between strangers is 17 points and it is 12 between full siblings. Everybody accepts that intelligence varies. But what makes some people smarter than others? How do nature and nurture interact to create that variation as we develop? Are differences in g set at birth, or can we increase someone's intelligence by nurturing them in the right environment?

NATURE AND NURTURE "Intriguingly, the heritability of intelligence is less than 30 per cent before children start school, rising to 80 per cent among adults"

Each of us is the embodiment of our genes and the environment working together from conception to death. To understand how these two forces interact

to reinforce their cognitive abilities. Given that an individual's ability to exploit a given environment

to generate differences in intelligence, behavioural geneticists compare twins, adoptees and other family members. The most compelling research comes

is influenced by their genetic endowment, and given that "better"

from identical twins adopted into different homesindividuals with identical genes but different environments- and non-kin adopted into the same

family environments tend not to produce overall increases in IQ, it is not surprising that attempts to raise low

home- unrelated individuals sharing the same environment. These and other studies show that IQ similarity most closely lines up with genetic similarity.

IQs by enriching poor school or home environments tend to disappoint. Narrow abilities can be trained up but g apparently cannot. This makes

More intriguingly, the studies also reveal that the heritability of intelligence- the percentage of its variation in a particular population that can be

sense if g is an overall property of the brain. That does not mean intensive early educational interventions lack

attributed to its variation in genes- steadily increases with age. Heritability is less than 30 per cent before children start school, rising to 80 per cent among

positive effects: among other things they may reduce rates of teenage pregnancy, delinquency and school

western adults. In fact. by adolescence, separated identical twins answer IQ tests almost as if they were the same person and adoptees in the same household

dropout. Besides, even if we cannot boost low intelligence into the average range, we do know how to

as if they were strangers. The surprising conclusion is that most family environments are equally effective

help all children learn more than they currently do and achieve more with

for nurturing intelligence - the IQ of an adult will be the same almost regardless of where he or she grew up, unless the environment is particularly inhumane. Why does the shared environment's power to

the intelligence they have.

Identical twins are a natural laboratory in which to study how intelligence develops

modify IQ variation wane and genetic influences increase as children gain independence? Studies on the nature of nurture offer a clue. All children enter the world as active shapers of their own environment. Parents and teachers experience this first-hand as their charges frustrate attempts to be shaped in particular ways. And increasing independence gives young people ever more opportunities to choose the cognitive complexity of the environments they seek out. The genetically brighter an individual, the more cognitively demanding the tasks and situations they tend to choose, and the more opportunities they have

2 July 20111 NewScientist I v

REALISING YOUR ASSETS IQ tests are designed to measure an individual's maximum cognitive ability but in everyday life we rarely perform at our best. Too often we arrive at work sleep-deprived, stressed, distracted, hungry, sick, addled by medicine or hung-over- all of which reduce cognitive acuity. This is compounded by the fact that many employers fail to recognise that mental performance varies over a day or week. Organisations squander their members' cognitive assets when they pace tasks poorly or flout normal sleep cycles, such as when schools start too early for the typical student, or when shift-workers have to put up with constantly changing schedules. What's more, to fully realise their abilities, individuals of different intelligence levels often require different kinds of support. Educational and military psychologists have shown that people of below-average intelligence learn best when given

cause cumulative cognitive damage, accelerating the effects of ageing and

Brain training games can only improve

concrete, step-by-step, hands-on instruction and lots of practice, whereas individuals of above-

increasing the risk of dementia. With vaccinations and care, most such

particularskills but not overall intelligence

average intelligence learn best when allowed to structure their own learning. One-size-fits-all instruction stunts the learning of both types of

assaults are preventable. We can also reduce exposure to human-made hazards thatdamagethe brain, such as pesticides, lead, radiation and

individuals. Schools can get far more out of pupils by educating them to their personal potential and employers can boost the achievements of their staff with well-targeted assistance such as mentoring,

exposure to drugs in the womb. The best way to get the most from our

supervision and training. Brainpower also needs protecting and nurturing.

native intelligence right into old age is to maintain good health of both body and mind. Healthy body, healthy mind

Chronic illness, alcohol abuse and head injuries

is a cliche because it's true.

"As modern life becomes ever more complex, technological upgrades can feel like brain downgrades"

vi I NewScientist 12 July 2011

SIMPLIFY YOUR WORLD Modern life is becoming ever more complex. When parents have to turn to their children to operate the latest electronic gadget, technological

throughout the day, which in turn requires planning for contingencies, recognising when blood sugar is veering

upgrades can feel like brain downgrades. The rising complexity of daily life can be a source of humour, embarrassment and inconvenience but given that

too high or low, knowing how to regain control and conceptualising the imperceptible but cumulative damage

the ability to deal with cognitive complexity is the essence of intelligence, this complexity can also be detrimental to personal well -being. One largely

caused by failing to maintain control. There is no set recipe for people with diabetes to follow - their bodies and

overlooked way we can achieve more with the intelligence we have is to recognise this and t ry to reduce needless complexity in everyday life.

circumstances differ. Moreover, they get little training, virtually no supervision and no days off. Effectively managing

The potentially harmful effects of cognitive overload are particularly clear in the field of

your diabetes is a cognitively complex job and poor performance has serious

healthcare. High rates of non-adherence to treatments are the bane of medical providers, and these increase when treatment plans are

consequences, including emergency room visits, lost limbs or eyesight, and even death. The lower the diabetic

more complex and patients less intelligent. Given the complexity of self-care regimes, it is hardly surprising that some people make dangerous errors

person's IQ, the greater the risks. Attempts to improve health outcomes in situations like this often focus on

or fail to comply. The effective management of diabetes, for example, requires a person to keep blood sugar levels within a healthy range, which

changing the behaviour of patients, but an equally effective approach might be to lower unnecessary cognitive hurdles

means coordinating diet, exercise and medication

to successful prevention, treatment and

BOOSTING BRAIN POWER Who wouldn't like to be more intelligent? If someone invented a safe and effective smart drug that could boost g by 20 points it would surely sell faster than Viagra. Unfortunately, everything we have learned about intelligence indicates that this is highly unlikely. If increasing intelligence is not an option, can you do more with what you have, by finding effective ways to work smarter, perhaps?

COGNITIVE ENHANCEMENT Brain implants, transplants and downloads may be far in the f uture, but other forms of cognitive

t iny electrical current. Each claims to improve one or more specific abilities

enhancement have a long history. For centuries people have used brain-boosting drugs. Caffeine and nicotine, for example, both increase alertness for

such as concentration, visual perception or memory, but the jury is still out on whether these

short periods. Today there are more choices than ever. One recent survey of US universities found that as many as 25 per cent of students routinely take Ritalin

improvements have real-world value. Perhaps the most universally accessible brain toner is one of the

or Adderall to boost memory and concentration- both drugs are actually designed to treat attention-deficit hyperactivity disorder. Another favourite is modafinil.

most ancient- meditation. Growing evidence suggests that training in mindfulness meditation improves not

licensed to treat narcolepsy and various sleep disorders, but which can also reduce fatigue and maintain alertness in healthy individuals burning

just psychological well-being but also produces measurable improvements in a range of cognitive areas, including

the midnight oil. There are dozens more drugs in the pipeline with t he potential for cognitive enhancement- some act on the same nicotinic

attention and memory, probably by reducing susceptibility to stress and distraction.

receptors as cigarettes; others are being developed for the express purpose of augmenting memory. Even if they are effective, however, such drugs do

Superfoods may make

not increase intelligence, they only enhance certain aspects of cognition such as memory or alertness. And there may be unknown risks associated with them,

you healthier but they won't increase your IQ

particularly those that have been developed for other purposes and have had few trials on healthy people. However much we would like to boost our brainpower, many of us are not prepared to take these risks. That might help explain the rise in recent years

"'

~ of so-called superfoods as a natural solution to

~ cognitive enhancement. Unfortunately, while eat ing

"'

~ blueberries, salmon, avocados, and dark chocolate a: ~ is obviously safer, it may not be as effective as many ~ people hope. If such "brain foods" work at all, it is ::> ~ probably primarily by promoting general health when "' consumed as part of a wholesome, balanced diet. ~ "'~ In our desire to be cleverer we are constantly on 0 5 the look-out for new cognitive enhancers. They range "' from the sublime, such as learning to play a musical ~ ~::.> instrument, to the impractical, such as transcranial ~ direct current stimulation, which involves placing J: l;l electrodes on the scalp to zap the brain with a ~

Zj uly 20111 NewScientist I vii

Linda S. Gottfredson Linda S. Gottfredson is a professor of education at the University of Delaware in Newark. She focuses on the socia I implications of intelligence, including how cultural institutions are shaped by the wide variation in human cognitive capability that is characteristic of a11 groups. She is also interested in the evolution of human intelligence and especially the idea that it may have been driven by a need to overcome novel hazards associated with innovation

NEXT NSTANT EXPERT Oavid Sloan VVilson

GROUP

SELECTION 6August

ARE WE GETTING SMARTER? Over the past century, each successive generation has answered more IQ test items correctly than the last the rise being equivalent to around 3 1Q points per decade in developed nations. This is dubbed the "Fiynn effect" after the political scientist james Flynn, who most thoroughly documented it. Are humans getting smarter, and if so, why? One possible explanation is that today's world supports or demands higher levels of intelligence. Flynn himself suggests that intelligence has risen in part because we view life more analytically, through "scientific spectacles". However, the idea that cultural environments have potent and widespread effects on how smart we are does not square with what we know about the high heritability of intelligence. Environmental variation contributes relatively little to the IQ differences in a birth cohort as its members mature over the decades. How, then, cou ld it create such big IQ differences across successive birth cohorts living in the same era? Another theory puts rising IQ down to physiological changes. In the past century human height has been increasing in tandem with IQ throughout the developed world. Better public health measures have reduced the need for our immune systems to consume resources to combat infectious disease, leaving us able to spend more on growth- and larger, smarter brains may be just one consequence. Not only that as more people travelled and married outside their local group, populations may have benefited genetically from hybrid vigour. viii I NewScientist I 2 July 2011

Inbreeding is known to lower intelligence, and outbreeding can raise it. lt is also possible that the Flynn effect does not in fact reflect a rise in general intelligence, or g. After all, can the average IQ of adults at the end of the second world war really have been 20 points less than today? That would put them in the bottom 10 per cent of intelligence by current standards, making t hem legally ineligible to serve in the US military on grounds of poor trainability. lt defies belief. Instead of an overall increase in g, perhaps just certain biologically rooted cognitive abilities are increasing. An IQ test comprises a series of subtests, and it turns out that scores in some of these have increased a lot - including our ability to identify similarities between common objects - whereas others have not increased at all- such as scores in the vocabulary and arithmetic subtests. That would imply changes in specific brain regions rather than the whole brain. The inter-generational rise in IQ test scores is a brain-twister for researchers trying to figure out what it means. Nevertheless, it does not undermine the use of IQ tests within generations. Current IQtests are not intended to give an absolute measure of intelligence akin to grams and kilograms, but only to rate an individual's intellectual capacity relative to others born in the same year - no matter what the cohort, the mean score is always set at 100. As for the variation in g that IQ tests measure, it seems as wide and as consequential as ever.

RECOMMENDED READING Intelligence: A Very Short Introduction by lan Deary (Oxford University Press, 2001) The Genetic and Environmental Origins of Learning Abilities and Disabilities in the Early School Years by Yul ia Kovas and others (Biackwell, 2007) The g Foetor: The Science of Mental Ability by Arthur jensen (Praeger, 1998) Correcting Fallacies about Educational and Psychological Testing edited by Richard Phelps {American Psychological Association, 2009) Intelligence, vol24{1) {special issue called Intelligence and Social Policy) Intelligence, vol 37(2) {special issue called Intelligence and the Brain) journal of Personality and Social Psychology. vol86, p 96 {the Special Section on Cognitive Abilities) Cover image joe McNally/Getty

ELCOME to Procyon B, a nearby star that's light years away from the sun, and not only in distance terms. Unlike the healthy star we circle, Procyon B is dim and dying. Having thrown off its outer layers, it is puny compared with the sun. And it is so dense that were you able to scoop up a spoonful of its material, it would weighs tonnes. So unlike our sun is Procyon B, in fact, that those seeking extraterrestrial life have long overlooked the star's potential. But we may have been too hasty, according to Eric Agol, an astronomer at the University ~:: of Washington in Seattle. Though dim and ~ diminutive, Procyon Band other white dwarf

stars like it could host planets sporting mild temperatures, oceans and living critters. With billions of white dwarfs in our galaxy alone, Agol's work opens up a new frontier in the search for intelligent life. What's more, even small telescopes could search the vicinity of such dying stars for potentially life-bearing worlds. "This is something an amateur astronomer could do," says Ago!. So far, the search for alien life has focused on planets orbiting stars similar in size, temperature and brightness to the sun. That makes sense: the universe's one known life-bearing planet orbits such a star. Since zoog, NASA's Kepler spacecraft has been > 2july2011 1NewScientist 137

scrutinising sun-like stars in its quest for Earth's twin. Among the 1235 candidate planets Kepler has found, 54 orbit their stars at just the right distance for water to exist in liquid form. Of those, only s are similar in size to the Earth, suggesting that they are rocky worlds rather than gas or ice giants, and Agol began to wonder if there was an easier way to detect small, Earth-sized planets. Dying stars hardly evoke visions oflife. White dwarfs are what most stars, including the sun one day, become after they run out of nuclear fuel. They owe their glow to leftover heat. The youngest are so hot they shine blue. As they cool, they turn white, then yellow and orange, and there they linger at a temperature similar to the sun's. The sun has been able to nurture terrestrial life because it has been stable for billions of years. A cool white dwarf is just as stable. So if any putative planets huddle close, why can't they develop life the way Earth d id? "My first thought was, 'that's crazy'," says Scott Gaudi, an astronomer at Ohio State University in Columbus. "Then the more I thought about it, the more sense it made."

A planet eclipsing a white dwarf will look like a solar eclipse

befall Mercury and possibly Venus and Earth in about 7 billion years. Within another billion years the red giant sheds its outer layers of gas to form a glowing planetary nebula. The exposed hot, dense core is a white dwarf. It would seem impossible for any close-in planet to survive such fireworks, but astronomers were stunned 20 years ago to discover planets around a different type of dead star known as a pulsar. Pulsars have gone through much greater drama than any white Habitable huddle dwarf: they are born in supernova explosions. One reason it seems so crazy is the way white The planets probably condense from a disc of dwarfs are born. After a sun-like star has gas and dust that encircles the pulsar after it burned the hydrogen fuel at its core, it has tom a companion star to shreds. balloons into a monstrous red giant more than Other clues to the possible origins of dead100 times wider than the sun. It engulfs and star planets come from the haul of planets already found around sun-like stars. Many of destroys any nearby planets, a fate that will

Life cycle of the sun Our sun and stars of similar mass go t hrough t he same stages as they age

38 I NewScientist IZJuly 2011

these stars have Jupiter-sized planets orbiting close by, but these could only have formed far from the star where there is sufficient ice and rubble. Their near orbits suggest that they must have migrated or been kicked in somehow from further out. Perhaps the same processes work around a white dwarf, shepherding frigid planets towards the warmth of their dim sun. Or planets might form anew after the white dwarf has formed if an orbiting disc of gas and dust exists. Despite their dramatic birth, white dwarfs usually exist in peace, just cooling off. Agol's calculations show that there is a period of billions of years when a planet in the right orbit around a cool white dwarf could be habitable (TheAstrophysica/Journal Letters, vol731, p L31). Because cool white dwarfs are only about a

ten-thousandth as bright as the sun, to stay warm a planet must huddle at one-hundredth of the distance between the Earth and the sun. Any habitable planets would complete their orbits every 4 to 32 hours, says Agol. If it were any shorter, the planet would be so close th at the pull of t he star's gravity would tear it ap art. At longer periods, the planet is so far out th at it would freeze. No one has ever fou nd a planet around a white dwarf. Yet astronomers are enth u siastic about Agol's idea because the diminut ive size of white dwarfs mean such planet s should be easy to find. When an Earth-sized planet passes in front of a star as large as the sun, it blocks so little of its light that only an expensive mission, such as Kepler, can detect the eclipse. But white dwarfs are as small as Earth, so a passing planet may well block all the star's light from reaching us. The planet's presence would look like a total solar eclip se every day, throu gh any b ackyard telescope that could see the white dwarf. "There are enough amateu rs out th ere with telescop es t hat could be p erfect for this sort of project," says Ago!. With billions of white dwarfs in the Milky Way, there are plenty of places to look. The n earest one, Sirius B, is probably too hot to have h abitable planets and Procyon B, 11.4 light years away, is t oo close to a bright star for most amateur telescopes to detect it. Bu t other white dwarfs fit the bill: Van Maanen's star is just 14 light years from Earth and is bright enough for a small telescope to observe. Wh ite dwarfs further away are dimmer and that means larger telescopes are needed. Agol says telescopes with mirrors b etween h alf-a-metre and a metre across are ideal. That's too big for most amateurs to have at home, but many keen star-gazers belong to ast ronomy clubs with access to such telescopes.

"Even amateur astronomers could search these dying stars for life-bearing worlds"

ALIENS OF THE TWILIGHT ZONE Life on a planet orbiting a tiny white dwarf would be quite different from life on Earth. Since any life-bearing planet in a white-dwarf system would orbit close to its star, the gravitational forces would be immense. They would cause the planet to rotate at the same rate it orbits the star;· says astronomer Eric Ago I at the University of Washington in Seattle. That means the same side of the planet would always face the star: the sun would never set on the hot. day side, whereas the night side would be freezing and forever in darkness. The star~ pull would also keep the planet upright on its axis and its orbit circular, so there would be no seasons. There would be no moon because the sta~ gravity would have torn any satellites away. A year would last only about as long

Daily eclipses The more people who look, the better. Even if close-in white-dwarf planets abound, only about 1 in 100 is going to be situ ated so that it can stop starlight from reaching Earth. Agol therefore wants to search thousands of white dwarfs. "I've thought about trying to coordinate amateur astronomers around the world," h e says. Even so, it could be a long slog. With the nearest and brightest white dwarfs scattered across the sky, a single telescope u sually m on itors just one at a time. Still, John Tonry, an astronomer at the University of Hawaii in Honolulu, hopes to bu ild an array of eight 25-centimetre telescopes called Atlas that w ill

as Earth~ day, so yout'.l need some other unit to reckon lengthy periods of time. Not everything would differ from Earth, though. The white dwarf sun would look much like our own, even down to its colour. And though a white dwarf is about one-hundredth the size of our sun, it would appear the same size as ours in the sky because it would be 100 times closer. If the air had the same composition as Earth~ air, then the sky would look blue,

just like our skies," says Ago I. But if you lived on the day-night boundary, yout'.l see

scan th e entire visible sky twice a n ight, principally to give early warning of an asteroid strike. "Atlas will get a look at 10,000 or 2o ,oo o white dwarfs every night," h e says. In the best possible scenario, in which every white dwarf has a planet, Atlas should start seeing eclipses within a week or two. Tonry says the cost of his proposed project is relatively modest, at $3 million. Far m ore am bitious and expensive is the Large Synoptic Survey Telescope, an 8-metre telescope to be built in Chile later in the decade. Designed to observe most of the sky, it will also yield evidence of close-in white-dwarf planets, if th ey exist. However they are fou nd, planet-indu ced eclipses of white dwarfs will be brief, lasting just a couple of minutes. Confirming the presen ce of a planet w ill be easy because it goes around its star in a m atter of hours. In con trast, eclipsing planets like Earth, with one-year periods, take m u ch longer to confirm. If Agol is right, we have neglected a type of star that may support life through out the galaxy. And we m ay not be alone in our folly. Any extraterrestrial astronomers living on a white dwarf planet looking for signs of life in t he universe are likely to be examining other white dwarfs. By doing so, they'll be missing the sun and the Earth . But who can blame them ? After all, detecting little planets around big stars like the sun is hard. It's a lot easier to catch such a world orbiting a white dwarf. •

a permanent sunset." For aliens living in the twilight zone, that would mean a perpetually red sun.

Ken Croswell is an astronomer in Berkeley, California. and the author of The Livesof Stors (Boyds Mills Press. 2009) 2 July 20111 NewScientist 139

Corvids are known as the "feathered apes" for their intelligence

40 I NewScientist I ZJuly 2011

Can a crow t hink? How about a fru it fly? Emma Young explores the mental lives of animals

TFIRST, the New Caledonian crow simply watches the menacing presence suspiciously, hopping around in circles to get the best possible view. Eventually, overcome by curiosity, it picks up a twig that it would normally use to forage for food and pokes the threatening object, before jumping back in apprehension. When the thing fails to respond - being a rubber spider- the crow gains confidence and returns to lift it this way and that, peeking at the underbelly. The behaviour, recorded in a study led by Joanna Wimpenny, in Alex Kacelnik's lab at the University of Oxford, certainly looks smart. You or I might well behave in a similar way were we to come across something strange and potentially dangerous. But what's really going on behind those beady eyes? A deliberate thought process or mere animal instinct? The question of whether other animals can think has troubled some of the greatest minds throughout the ages. Aristotle and Rene Descartes believed that animal behaviour is governed purely by reflexes, while Charles Darwin and the 19th-century psychologist William James argued that animals might have complicated ment al lives. We are now closer than ever to settling this debate. Taking into account a wealth of reports of ingenious animal behaviours, g including those of the New Caledonian .... ~ crows, many biologists have come to believe that certain creatures really do have 3 rudimentary thoughts. Meanwhile, the latest §1- brain-imaging experiments are helping us ~ understand what kind of anatomy might be v> ~ necessary for a thinking brain. Although it's ~ unlikely that their mental lives are quite as u ~ complex as ours, there's much more going

g 2 July 20111 NewScientist 141

plans for times ahead. In 2006, researchers at Germany, found that in a staged food hunt, the University of Edinburgh, UK, found that chimps will try to guess where their this ability extended to hummingbirds. They competitors might have looked first, so that can remember the location of certain flowers they can search the less obvious locations and how recently they had visited them and (Proceedings ofthe National Academy of then use this information to guide future Sciences, vol1o8, p 3077). Whales, bears and behaviour. Work published since then suggests dogs haven't yet proved their abilities in this that primates, rats and octopuses show some kind of task, but they nevertheless display aptitude for forward planning. some signs of empathy that suggest they too The real test, however, is whether the might have a relatively advanced mental life behaviour is flexible . If not, the act might just (see "You've got me feeling emotions", below). be an evolved instinct, however complex it appears to be. The corvid family, which Making a "pass" includes crows, ravens and jays, does seem to show this on-the-fly ingenuity. The Kacelnik Clever as these behaviours are, they may lab's New Caledonian crows, for instance, nevertheless lack one important characteristic showed off their ability to use an old tool for of human thought, called "metacognition". This is the ability to monitor and control a new job, when they probed the threatening rubber spider with their foraging twigs. The memories and perceptions, allowing us team published their work earlier this year to think that, "I know that I know this" or "I'm not sure that I'm right", or to feel (Animal Cognition, vol14, p 459). Then there's that someone's name is on the tip of your the case ofBetty, a particularly intelligent crow who would bend a piece of wire on a twig tongue. According to David Smith of the State University of New York, Buffalo, its in order to hook some food out of a test tube at the other side of the room. It is amazing that importance to human thought is comparable she could remember the food in the tube as to that oflanguage and tool use. Evidence she flew over to the branch, and then use the for metacognition in other animals would memory to solve a problem that wasn't therefore strike a blow for the existence of to take the "all-or-nothing" experiments. immediately in her field of view, says David the animal mind. This suggested that when given the opportunity, Smith began exploring the subject with they were fully ea pable of assessing their Edelman ofThe Neurosciences Institute in San Diego, California. "That, to me, is strongly a flurry of papers in the early 20oos. For confidence in the task, providing compelling suggestive of a conscious process at work." example, in one experiment, he presented evidence for monkey metacognition. Corvids might even be able to second-guess a group ofmacaques with an image. After Further research suggests they are part another bird's behaviour. For example, of a select set with this ability (Trends in a short delay, the monkeys had to try and experiments by Bernd Heinrich at the select the image from a group of four. The Cognitive Sciences, vol 13, p 389). Chimps, like University of Vermont and Thomas Bugnyar prize was a tasty peanut, but if they got it macaques, have demonstrated metacognition at the University of Vienna, Austria, found wrong, they won nothing. In one stream of time and again, but capuchin monkeys, that ravens will take steps to protect a secret experiments, however, the monkeys could although intelligent in other areas, seem food cache from other ravens that might have forfeit the chance to win the peanut, in return to fall at this hurdle. The results for dolphins seen them hiding it, but were unconcerned for a guaranteed prize of a less desirable pellet aren't clear-cut, though it's pretty certain that about ravens stuck behind an obstacle that creatures like the humble pigeon just can't of processed monkey food. Smith suspected would have blocked their view (Proceedings of that the monkeys would take this option to step up to the challenge. the Royal Society B, vol272, p 1641). "The work "pass" if they weren't sure of the answer. Finding out whether other intelligent certainly suggests that these birds have the He was right. Monkeys given the chance species like dolphins, and perhaps crows, have capacity to monitor both the experiences and to pass performed much better on the tests metacognition is crucial to our understanding perceived mental states of others," says they did choose to take than those made of the mind, says Smith. We need to know Edelman. In other words, they have a basic "theory of mind", which should not be possible without some kind of thought process. Few other creatures are thought to have While some researchers University of Colorado, Boulder, and swam slowly, but his sister this ability, but not surprisingly primates are among this elite. If chimpanzees are stealing interested in probing animal caught salmon for him to eat, thinks there are clear signs that food, for example, they will be sure to be minds are concentrating on tests animals can experience empathy, and her support was crucial for of intellect. others are looking for spite, grief, gratitude, love and his survival. Such evidence, he extra quiet if another member of the group is within earshot. More impressively still, they evidence of an emotional life, even awe. He cites, for example, thi nks, points to a sophisticated type of consciousness in a range which many think is an important a story of two orphaned grizzly seem to be able to guess how another might of animals, including dogs, have acted in the past. Earlier this year, constituent of consciousness. bear cubs in Alaska. The male Marc Bekoff, a biologist at the elephants and humpback whales. had been wounded, and limped Michael Tomasello at the Max Planck Institute for Evolutionary Anthropology in Leipzig,

You've got me feeling emotions

421 NewScientist I2July 2011

"If chimps are stealing food, they will be sure to be extra quiet if one of their group is within earshot"

Though clever, chimps are unable to grasp abstract concepts

whether metacognition developed only once, in the line of Old World primates that leads to apes and humans." Or did metacognition develop repeatedly and convergently, as the last frost that settles on all the highest peaks of cognitive sophistication in dolphins, crows, apes and people?" If that turned out to be the case, it would shake up our understanding of the evolution of the primate brain, he says. With such a broad array of complex behaviours, many evolutionary biologists have conceded that at least some species have the rudiments of thought. Not everyone is convinced that we humans should step down from our pedestal just yet, however. Daniel Povinelli oft he Cognitive Evolution Group at the University ofLouisiana, Lafayette, for example, agrees that some animals are capable of thought, but he believes we are unique in our "higher" level of reasoning that allows us to grasp abstract ideas. Chimps, for example, just don't get abstract physical concepts, like weight, gravity and the transfer offorce. Place a banana near a chimp's cage and provide them with a few potential tools to reach their snack, and they're just as likely to try something floppy as they are to reach for a rigid rod. He concludes that chimps can reason about things that are directly perceivable, but only humans have a higher level of thought that doesn't solely rely on sensory input, allowing us to form

more abstract concepts, like that of gravity or force. He also doubt s that chimps have a theory of mind. "Message from Earth to comparative psychology," he says, "humans are different." Wynne takes a more negative view but admits that he is in the minority. "The centre of gravity in the field is with people who would say that certain kinds of complex behaviour indicate consciousness in at least some animals," he says. "But then there are the miserable sods like me, who don't think that really any animals show consciousness, because we set the bar higher." Like Descartes, Wynne has come to the conclusion that language is essential for thought. "That's because you can show me an ingenious behaviour- that does not involve language - and I conceive of doing it without being aware that I was doing it. The only behaviours that I cannot conceive of doing unconsciously are ones that involve using language." Think of the complex actions that humans do all the time and that don't require consciousness, he says. We can operate a complex piece of machinery -like a car, for example - without thinking about it. The problem, says van Swinderen, is that behavioural studies can only go so far in addressing this problem. "You could show an animal like a fly doing something like putting on a hat and wearing clothes, and

still some people would say it's just a series of reflexes," he says. For this reason, some researchers are calling for new approaches that might settle the argument once and for all. Brain imaging provides some of the most promising possibilities. Aaron Schurger ofPrinceton University and colleagues, for example, have used functional MRI to study signatures of consciousness in the human brain. They have found that there is a similar pattern of neural activity each time we become conscious of the same picture of a house or a face, but not if we process information from the image unconsciously (Science, vol327, p 97). Such work suggests that conscious thought does not depend on any uniquely human region of the brain, meaning there's no anatomical reason that it should be exclusive to people. Other neuroscientific work has, however, revealed some important prerequisites for consciousness that might be present in some, but not all, animals. Neural connections that allow the thalamus to relay information from the senses to the cortex, for example, seem to be vital for conscious awareness. Other mammals also have such a pathway, so "at the very least they have the substrates in place for consciousness", Edelman argues. "With recent advances in avian functional neuroanatomy, we can probably say the same about birds." This would seem to fit with the conclusions of the behavioural studies. If we're on the hunt for evidence of conscious thought in other animals- whether vertebrates like reptiles and amphibians or invertebrates like the octopus and squid- it makes sense to look for analogues to the thalamus and cortex in those species as well, he says. Even if these studies prove to be successful, some people will nevertheless take a lot of convincing. Wynne, for one, maintains that the debate is still best left for late night drinks, as he thinks no data will ever answer the question. But Edelman is optimistic that looking for animal equivalents of the thalamus and cortex will settle the arguments. "As far as I'm concerned, this could be the way out of centuries of debate." • Emma Young is a writer based in Sydney, Aust ralia Zjuly 20111 NewScientist 143

CULTURELAB

The dramatic life of Doctor Dee David Robson gets the story behind a new opera about the 16th-century mathematician DrDee

....

Director Rufus Norris works to bring Damon AI barn's opera to life

Palace Theatre, Manchester International Festival, until9 July JOHN DEE, the 16th-century mathematician and occultist at the centre of Queen Elizabeth I's court, has inspired some of the world's greatest minds. Shakespeare evoked him as the enigmatic conjuror Prospero in The Tempest, while Christopher Marlowe created the powerhungry Doctor Faustus, who sold his soul to the devil for greater knowledge. "Those are rather fantastical fictions," says Rufus Norris, who is directing a new opera about Dee written by Damon AI barn. "But sometimes the truth is far more interesting." The opera, Dr Dee, which premieres at the Manchester International Festival in the UK this week, was conceived when festival organisers approached graphic novelist Alan Moo re who created Vfor Vendetta and From Hell - to work on a new Copernicus's model of the project about the life of an universe. He also developed obscure but important figure mathematical techniques to from English history. Moo re chose help sailors navigate by the stars, Dee as his subject, and Albarn, meaning that boats could venture best known as the lead singer and out on new routes away from the coast - a key development in songwriter of the bands Blur and Gorillaz, came on board to write exploring the New World and the music. Moo re later left "for reasons that we're not quite sure "Oee's magpie curiosity of", says Norris, but the seeds of was ultimately his the idea had been sown. downfall, as he turned to the occult in the 1580s" Albarn and Norris could hardly have had a richer source ultimately building England's of inspiration for their opera. Dee's early life was marked by empire. And, like other intellectual successes that earned intellectuals of his era, after the him respect in Elizabeth's court. emergence of the supernova in He popularised Euclidean the constellation Cassiopeia in geometry in academic circles 1572, Dee likely contemplated the universe as a never-ending and was an early supporter of 44 1NewScientist 12 July 2011

1

expanse of space and stars, says his biographer Benjamin Woolley. Dee's magpie curiosity was ultimately his downfall, however. Frustrated by the limits of his knowledge, in the 1580s he turned to the occult under the guidance of the medium Edward Kelley. Yet Kelley - a charismatic and manipulative individual - seems to have had an ulterior motive. "He took a fancy to Dee's wife," says Woolley. While the group was in Bohemia, Kelley persuaded Dee that the angel Uriel had ordered them to share their wives. It was a massive turning point in Dee's life. His relationship with Kelley collapsed, and he returned home to find his famous library ransacked by rivals. Thanks to his

forays into mysticism, he also received an icy reception at the court that had once adored him. Dee eventually died in poverty. So how do you dramatise such a life? Norris and Albarn have taken an unusual approach. Though he will sometimes sing as Dee, Albarn will play himself. 'Tm singing but I'm not an actor I'm not wearing a ruff and tights," he says. The opera will open with Albarn by himself, before cutting to Dee's deathbed to explore the incidents and characters that shaped his life. Albarn's music will be performed with a mixture of traditional Elizabethan instruments and west African drumming by Nigerian composer anddrummer Tony Alien. "The sounds that travelled from Africa into Europe at that time were really important," says Albarn. "That's been somewhat passed over in modern history." The show also features 23 members of the BBC Philharmonic Orchestra. "It's a big sound." The ensemble hopes to explore the resonances between the England of today and Dee's nation at the cusp of its golden age. "Dee was a huge figure in the reign of Elizabeth I, and here we are at the end of another Elizabeth's reign, her twilight years - and the empire has sort of evaporated," says Albarn. "I think there's a real connection between these two moments." The result would have perhaps found favour with Dee, says Woolley. "It's just the kind of weird and wonderful experiment that he would have loved." •

For more books and arts coverage and to add your comments, visit newscientist.com/blogs/culturelab

Statistical thriller Who'd have thought that Bayes's theorem could be turned into such a gripping story?

1

The Theory That Would Not Die by Sharon Bertsch McGrayne, Yale University Press. £18.99/$27.50

Reviewed by David Robson

FEW single ideas can boast such an impressive 'Cl resume. What ... " " -· C!> """lad -· ...WO. else could have ~lllmt• possibly cracked tfftlilllnol-~ ., the Enigma code in ..__ _ ____, the second world war, predicted John F. Kennedy's close-run win in the tg6o US presidential election, and landed a winning blow against the nefarious antics of the tobacco industry? The secret to these successes is a humble little theorem called Bayes's rule that allows you to assess the probability of one event from observations of an associated event. On election night, for example, you might use an early outcome from one US state to help predict the winner in states that have not yet announced their result. This simple rule has experienced

- -' -"''

The US applied Bayes's rule to the task of tracking Soviet submarines

the second world war, and the US navy's later use of the technique to track Soviet submarines. Eventually, the theorem wormed its way into medical journals, insurance forecasting and business decision-making, before its eventual triumph in the age of the internet, as it became essential for spam filters, translation software and much more besides. In these less dramatic periods, a host of colourful characters and their bitter rivalries carry the tale. McGrayne can capture these mavericks in a single sentence: we are told that Robert Osher Schlaifer, who helped introduced the theorem to business, was "hot as a pistol, sharp as a knife, clear as a bell, quick as a whip and as exhausting as a marathon runner". Despite these colourful descriptions, the book is not always an easy read. Even with a mathematics degree, I struggled to visualise just how Bayes's rule solved many of these problems. And while McGrayne's writing is luminous when describing the drama of the cold war, her attempts to portray earlier periods in a modern context sometimes fall flat. We are told that a theological pamphlet was "a kind ofblog", for example, and

a turbulent history since Thomas Bayes outlined his ideas in the mid-17oos. The sticking point has been the fact that you must first take a stab - sometimes not even a very well-informed one at the relative probabilities of your hypotheses, before plugging "Bayes's theorem became essential for internet in the relevant data to achieve spam filters, translation a more accurate answer. software and much more" Researchers trying to root out any form of subjectivity in their methods found this kind of she feels the need to describe a guesswork outrageous, leading philosophical thought experiment to the theorem being shunned as a type of computer simulation. over the next two centuries. These are minor gripes, Sharon Bertsch McGrayne's however, and to have crafted a The Theory That Would Not Die page-turner out of the history is the first popular science book of statistics is an impressive feat. to document the rocky story If only lectures at university ofBayes's rule. At times, her had been this racy. Then again, tale has everything you would perhaps we should expect nothing expect of a modem-day thriller. less from a theory once described Espionage, nuclear warfare and by one ofGoogle's representatives cold war paranoia all feature as she as" the crack cocaine of statistics ... seductive, addictive and tracks the theory's crucial role in Alan Turing's code-breaking during ultimately destructive".

Red alertness Why Red Doesn't Sound Like a Bell: Understanding the feel of consciousness by J.Kevin O'Regan, Oxford University Press, £40/$59.95

Reviewed by Michael Bond ~~

THIS book is yet another attempt to present and explain the mysteries of consciousness for a broad audience. To his credit, J. Kevin O'Regan takes a provocative and fresh approach to a discipline that often seems to be chasing its tail in search of a way forward. O'Regan is an experimental psychologist best known for his work on vision and perception, in particular for his eo-discovery of change blindness - the way people fail to notice what seem like obvious changes in a scene before them. In the past decade he has pioneered a new theory of seeing to explain this and other phenomena and describe why our visual system appears so effective despite its many imperfections. We see the world, he claims, not by piecing together a picture postcard-like representation in the brain, but by interacting with our surroundings and inferring visual knowledge based on our previous experience. O'Regan begins with an overview of this " sensorimotor" account of vision before applying its principles to the hard problem of consciousness: why sensations feel the way they do. He offers an alternative way of looking at the issue, above all to provide a better method for linking scientific understanding with people's everyday experience. "We should not think of feel as something that happens to us, but rather as a thing that we do," he explains. Or, I should say, tries to. Though I felt intellectually exercised, in spite ofO'Regan's best efforts, I finished the book not much clearer about the nature of consciousness. 2 July 2011 1NewScientist 145

CULTURELAB done and we begin the heavier work ourselves." The choice of men for the expedition had surprising roots in social Darwinism: it was guided by There was a lot more to polar exploration eugenics, a new "science" of racial inheritance inspired by natural than planting a flag, says Michael Bravo selection. Clements Markham, the vituperative president the Royal glaciology, and eugenics. By Geographical Society, patronised An Empire of Ice: Scott Shackleton sounding, dredging, and taking a select group of vigorous, and the heroic age of Antarctic temperature measurements they youthful men to become explorers. science by Edwa rd J. Larson, discovered evidence for primitive Markham believed that social Yale University Press, £18.99/$28 life forms on the sea bed and breeding was paramount. Four t\N l MPIItl JUST over a century uncovered the role of the Southern of the officers on the earlier Ocean's cold waters as a driver of Discovery expedition, for instance, ago, a group of L"'~l K I explorers set out global ocean circulation . were related by blood or marriage. •• Their work to determine the One of them, Charles Royds, was from Britain on a mission that would shifting location of the south "a first cousin once removed of the wife of a cousin whose wife was cost many of them magnetic pole helped scientists their lives. This one of his own second cousins" at the Royal Society understand f IJ\1 \IUH I \ICSO\ changing patterns of magnetic much of Captain close enough for Markham to Scott's Terra Nova expedition is variation, a problem that had conclude that he should be one well known. In this fascinating for many decades eluded them. of the "Antarctic heroes". Larson's intriguing accounts In the bitter Antarctic crucible book, Edward J. Larson places the expedition, which ran from the explorers also experimented begin to reveal the bigger with their own bodies, using 1910 to 1913, in context as the last picture of early scientific "man-hauling" techniques research in Antarctica and its ofthree successive expeditions that aimed to solve some of borrowed from Arctic exploration. place in European geopolitics Antarctica's most important Harnessed to their sledges, pulling of the time. In so doing he loads of hundreds of pounds each, also shows how the continent scientific mysteries. Chapter by chapter, Larson began to play a central role in they purposefully tested their endurance to breaking point. contemporary understanding leads his readers through the Supplementary travel technologies of the Earth sciences. puzzles ofVictorian science were deemed unmanly. After the that defined the goals ofRobert Scott and Ernest Shackleton: expedition's ponies died, Edward Michael Bravo is a historian and senior lecturer at the Scott Polar Research geology, geomagnetism, Wilson reportedly exclaimed: cartography, oceanography, "Thank God the horses are now all Institute, University of Cambridge

Antarctic pioneers

.~

--- -.

_,

r

·~

.. 46( NewScientist I 2July 2011

play in which genes are one actor among the rest. The gene's fall from leadership is the result of geneticists' growing attention to epigenetics - a form of genetic change that is essentially the gene's way of responding to its surroundings but which does not involve alterations in the gene's DNA. So mothers who suffer severe stress during pregnancy have children more sensitive to stress, who pass that sensitivity along to their own children. Readers new to epigenetics will find the book a pretty clear introduction, but its limited scope is likely to leave more advanced readers wanting more detail.

Hysterical history Medical Muses: Hysteria in nineteenth-century Paris by Asti Hustvedt. Bloomsbury, £16.99; W. W. Norton, $26.95

Reviewed by Wendy Zukerman

DOCTORS no longer diagnose _., , people with hysteria. Its symptoms still exist, but now the paralysis and epileptic-like fits that once marked the disease are taken to be signs of modern ailments such as depression or fatigue. So argues Asti Hustvedt Inheriting the past in Medical Muses, an engaging book which follows the lives of Epigenetics: the ultimate mystery three hysteric women treated at af inheritance by Richard C. Francis, the Salpetriere Hospital in Paris, Norton, £19.99/$25.95 France, between 1870 and t8go. Reviewed by Bob Holmes With infectious curiosity, IN THE biological Hustvedt writes of medicine's theatre, genes inadequacies at a time when are the directors, psychological problems were not commanding thought to manifest as physical the rest of the symptoms. Though doctors could cell's biomolecules find no physical cause, she makes to their proper the case that the women were places and cueing not faking their symptoms their lines. That has been the a common accusation in the dominant metaphor in biology 19th century. It's an accusation for decades. that, Hustvedt laments, continues In Epigenetics, Richard Francis today with conditions whose argues for a more improvisational cause remains unknown.

Stay connected to a digital world of knowledge -wherever you are.

____

SUPERCHARGE

.,_ YOUR BRAIN

New Scientist is now available as a digital magazine through our on line partner Zinio, meaning it's always at your fingertips on your iPad or tablet computer, wherever you are. Instant delivery

New Scientist delivered to you digitally every week. Always available

Your copy will always be available for you to read. Easy to read

Full colour, full screen reading with easy zoom.

To find out how to get connected with a digital magazine subscription, visit: www.zinio.com/newscientist

NewScientist Jobs

Incorporating Sciencejobs.com To apply on line visit newscientistjobs.com

East Coast Office 225 Wyman Street Waltham. MA 02451 Email NS5ales@NewScientist .com Phone 781 734 8770 Fax 720 356 9217

West Coast Office 201 Mission Street. 26th Floor San Francisco, CA 9410 5 Email NSSales@NewScient ist.com Phone 4159083353 Fax 4155436789

calls may be monitored or recorded for staff training purposes

BIOLOGY Associate/Sr. Associate Scientist -- Molecular/Cell Biology- Oncology AstraZeneca US MS- Mississippi We are seeking a Senior Associate Scientist with expertise in cell and molecular biology.The successful candidate will become an integral member of an oncology bioscience team focused on the discovery and delivery of novel anti-cancer therapies. For more information visit NewScientistjobs.com job ID: 1401196362

Associate Principal Scientist AstraZeneca US DE - Delaware As part of the newly formed R&D Information department, the Discovery lnformatics capability has a mandate to address the significant data management, integration and analysis challenges at all stages of drug discovery/early development, including target discovery, lead identification & optimisation, compound safety analysis & prediction, biomarker discovery and patient/disease segmentation. For more information visit NewScientistjobs.com job ID: 1401193977

dedicated to advancing the biomedical sciences by supporting research and other scientific and educational activities. Burroughs Wellcome Fund Awards For more information visit NewScientistjobs.com job ID: 1401192809

Pharmacology Faculty 12-Month Position, Lake Erie College of Osteopathic Medicine Lake Erie College of Osteopathic Medicine (LECOM) PA - Pennsylvania The successful applicant will have a strong desire to teach and advise osteopathic medical students and to contribute to the development Biomedicallnformatics Principal Scientist 1- Cell/ Lead Biology- Oncology of the COM through service and Scientist- Real World Evidence AstraZeneca US research. Experience teaching in a AstraZeneca US United States medical school plus a track record DE - Delaware in obtaining research grants is We are seeking asenior PhD level You'll support our Innovative scientist with strong cancer related desirable. Medicines and Global Medicines drug discovery experience. The For more information visit Development teams by advising on individual will become a key member NewScientistjobs.com job ID: the best computational approaches of a team involved in the discovery 1401191798 to deliver real world evidence-based of novel anti cancer therapies. decisions. Not only will you optimize For more information visit all relevant data, information and Physiology Faculty NewScientistjobs.com job ID: knowledge, you could also drive 1401193980 12-Month Position, Lake Erie College of Osteopathic the delivery of processes, tools, and approaches to manage drug project Medicine information and knowledge. Sr. Scientist/Principal Lake Erie College of Osteopathic For more information visit Scientist, In-Vivo/In-Vitro Medicine (LECOM) NewScientistjobs.com job ID: Pharmacology - Infection PA - Pennsylvania 1401193979 AstraZeneca US Preference will be given to United States candidates with 3 years or more The successful candidate will utilize experience teaching in a medical setting. Qualified candidates will Clinicallnformatics his/her pharmacology experience - Associate Principal to support drug discovery be considered for Discipline Director. lnformatics Scientist projects in the Infection area.The The successful applicant should AstraZeneca US candidate will be responsible for possess a strong desire to teach independently designing and DE - Delaware and advise osteopathic medical The goals of optimally designing & implementing studies to determine students and to contribute to the interpreting clinical trials, integrating the pharmacological properties of development of the college through & mining medical knowledge, and novel antibiotic compounds. research and service. For more information visit For more information visit enriching our understanding of the NewScientistjobs.com job ID: healthcare environment offer a NewScientistjobs.com job ID: significant challenge for the clinical 1401193975 1401191799 development of new medicines. For more information visit NewScientistjobs.comjob ID: Career Awards Bioinformatics Scientist 1401193974 Burroughs Wellcome Fund (00401