BEYOND JEOPARDY! Bright future for TV's favorite supercomputer
Time warps
Invisibility o Cosmic travel
STRANGE SCIENCE OF EVERYDAY LIFE Finding the extraordinary in the ordinary
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CO NTENTS
Volume 209 No 2BOO This issue online www.newscientist.com/issue/2BOO
News
6
4
UPFRONT
Obama bids to protect US science. Non alcoholic wine shows up in alcohol test
Is Watson better than human?
6
THISWEEK
Flies sniff out quantum vibrations. Andean settlers' cancer-fighting secret. Global early warning system for floods. Why some women get monthly mood swings. First genetic explanation for bird migration. Periodic table of shapes. Mice cured of Down's-like learning problems
A bright future awaits the supercomputer after its quiz show turn
17 IN BRIEF
Star-less planet could harbour life. "Invisible" spiders cure phobia. Snails can sleep. Phone numbers with text appeal. Bees' buzz bugged
Technology
COVER STORY
34 Strange science of everyday life Another day filled with time warps, invisibility and cosmic travel
23
Smartphone app improves music at festivals. Augmented reality helps police track suspects. Wiii4G network kill GPS?
3
EDITORIAL
Opinion Cover image Lorenzo Petrantonl
28 29 30 32
46
Debut of IBM's Watson marks a turning point for artificial intelligence Real life on Mars We're looking in all the wrong places, says Alfonso F. Davila One minute with... Lily Cole How the campaigning model helps India's elephants LETTERS Trials on trial. Robot autonomy Spotting psychopaths Probing the US's most dangerous prisoners tells Kent Kiehl what makes a broken brain
Features 34 Strange science of daily life
(see above left) Revamping crop plants' outdated photosynthetic machinery is just what we need to boost yields 46 Virtual virtue (see left) 42 An upgrade for plants
Virtual virtue How to look your best in cyberspace
Culturelab 50 World Wide Mind makes a compelling
case for a future in which we feel other people's emotions via brain link-ups 51 Analogue art Media pioneer Nam june Paik's major retrospective show. Plus: Crossing the medical rubicon, and comic-book genomics
(l.. IReed Business nformation
Coming next week
...
Quantum loopholes Close them and we'll understand reality
Regulars 30 ENIGMA 56 FEEDBACK
Radon health claims Clear way thro ugh cloud
57 THE LASTWORD 52 JOBS & CAREERS
Give peace a chance Noise, begone!
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19 February ZOlll NewScientist 11
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Rise of machine thinking Watson's debut marks a turning point for artificial intelligence
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"I PROPOSE to consider the question, 'Can machines think?'." With that evocative opening line, the British mathematician Alan Turing raised the prospect of machine intelligence 6o-odd years ago. Turing suggested that we could consider a machine to think like us if its responses were indistinguishable from a human's. Before long, the media was fantasising about robot cleaners and computers that could fly planes. Today, since humans still scrub floors and land jets, there is a perception that artificial intelligence has failed to deliver. That feeling is not justified. It is true that the task of building a thinking machine proved harder than the field's pioneers anticipated. Yet AI methods developed over the last 6o years
have changed our lives, from improving our search engines to creating automatic translation systems, to give just two examples. The long-promised robot cleaners have even appeared on the market. After this week, however, the image of AI will change. A computer called Watson, the
"We are much closer to finding out if machines can think than many people realise" work of IBM, is taking on two previous human winners of the US quiz show Jeopardy! (see page 6). Questions are packed with clever turns of phrase and subtle references, and cover a vast range of topics. Many AI researchers thought that achines were not ready to take on such a
Food revolution FOR a reminder that the world is in the grip of a food crisis, look no further than this year's uprisings in Tunisia and Egypt. Both were triggered in part by soaring prices, which are at an all-time high after extreme weather- especially last year's heatwave in Russia- took its toll on agriculture. Now the wheat crop in China,
the world's biggest producer, is threatened by drought. If the crop fails, prices will rise further as China imports wheat to make up the shortfall. More plentiful harvests elsewhere might lead to lower prices later in the year, but any such respite will only be temporary as the weather becomes more unpredictable. As the saying goes: "Climate trains the boxer
but weather throws the punches." There are some simple measures, not least tackling the shocking levels of waste, that will make more food available in the short term. But that boxer is going to punch ever harder as the planet warms. That makes it essential to get started on ambitious technological fixes, such as upgrading the photosynthetic machinery in plants (see page 42). Otherwise our food supply will struggle to get off the ropes. •
This way for a polished persona
reputation and gain control over their virtual personas, as we report on page 46. At the moment, this is a relatively discreet activity, but it's not much of a stretch to imagine that individuals could become as preoccupied with persona management as companies are with using search engine
optimisation to boost the ranking ofwebsites. And today's simple strategies - such as pollinating links to an approved CV - are bound to become more complex. Search engines will then have to figure out how to distinguish "white hat" (ethical) from the "black hat" (unethical) efforts to burnish online personas. •
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challenge. They were wrong. Although Watson's appearance on Jeopardy! marks another step towards creating machines that think like we do, there is still some way to go. Answering questions is one thing, engaging in conversation is quite another. To pass the Turing test, Watson would have to chat to people and convince them it was human. Despite IBM's hard work and ingenuity, Watson would fail because, as its makers admit, it makes silly mistakes and is not yet capable of open-ended dialogue. Nonetheless, Watson's game show performance will convince many that we are much closer to answering Turing's question than they had realised. After all, if subtle wordplay can be mastered by machines, then what other human behaviours might now be within their grasp? •
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EVER tried googling your name and been shocked by the results? You are not alone - in fact, an entire industry has sprung up whose sole purpose is to help people manage their online
19 February 2011 1 NewScientist 1 3
UPFRONT For richer or poorer IF IT were up to the White House, 2012
that the remainder of the budget for
would be a bumper year for some
2011 be subjected to the biggest
areas of government-funded science
round of spending cuts in US history.
in the US. The reality may well be rather
Environmental Protection Agency
House of Representatives gets its way.
would have its budget slashed by 29 per cent relative to 2010. The
On Monday, President Barack Obama presented his2012 budget
Prevention would suffer a 22 per
funding to a number of science
cent cut. and the Department of
agencies above 2010 levels, including
Energy's Office of Science would
a 13 per cent increase for the National
face an 18 per cent cut.
and a 10.7 per cent increase for the
NEW ZEALAND has a novel solution for dealing with a crap situation: import dung beetles. The country has approved the release of 11 Australian species to manage its massive heap of livestock dung. Adult dung beetles lay their eggs in manure, which the brood feed on after hatching and break down into sawdust. An inhabited mound of dung can disappear in 48 hours, compared to a month for one that is left out in a field. That may seem unimportant, but for a nation with a large cattle population, it's not. As the mounds rot, they release greenhouse gases and their nutrients and bacteria leach into waterways. Manure accounts
Such cuts "would cripple our ability to advance education and research
Department of Energy's Office of
that most people agree are essential
Science, to $5.4 billion.
investments in our future", says john
The request now goes for approval
Neither Australia nor New Zealand have native beetles that can handle livestock dung pats. But in the late 1960s, Australia introduced some from Europe and Africa. "They've been hugely successful," says Shaun Forgie of Landcare Research in Auckland, New Zealand. And it's not just the environment that can benefit. Forgie points out that removing the pats should also get rid of flies and parasitic worms that breed in dung: in Hawaii, they cut pest flies breeding in dung by 9 5 per cent.
Centers for Disease Control and
request to Congress. It would boost
Science Foundation, to $7.8 billion,
Cow dung away
Under these proposals, the
different, if the Republican-controlled
Holdren, director of the White House
or amendment to Congress, where it faces stiff opposition. On 11 February,
Office of Science and Technology
the House of Representatives
discussed in the House this week, so
Appropriations Committee proposed
stay tuned.
Tainted genomes
because there are stringent protocols in place for handling infectious diseases (PLoS One, DOl: 10.1371/journal. pone.oo16410 ) O'Neill did not look at the human genome, but she says it may also have been contaminated with DNA from lab workers. She thinks lab practices will have to become tighter, particularly for projects designed to scan people's genomes for sequences that affect disease. "You wouldn't want to be told that you had a sequence that gives a high risk of cancer when in fact you didn't," O'Neill says.
TIME to run a tighter ship? Up to 18 per cent of the genomes sequenced so far seem to be contaminated with human DNA, likely because oflax lab practices. Rachel O'Neill and colleagues at the University of Connecticut in Storrs went through 2749 genomes, including bacteria, viruses, plants and animals. They found that 492 were similar in one respect: they contained a snippet of human DNA called AluY. Only the influenza genomes were completely clean, probably
Policy. The funding proposal is being
.
Buffalo to be culled THE slaughter of hundreds of buffalo straying from Yellowstone National Park has been given the legal green light in Montana. The wild buffalo, which are classed as "near-threatened", can wander beyond park boundaries during the winter in search of food. Ranchers worry that they will pass the disease brucellosis to cattle in Montana, which is currently designated "brucellosis-free". The infection does not usually cause
"Within 48 hours, beetles can break down a patch of cow dung into sawdust that fertilises the soil" for around 14 per cent of New Zealand's emissions of nitrous oxide, a powerful greenhouse gas. Beetles can make short work of these problems. 4 1 NewScientist 1 19 February 2011 HotMags - Hot Magazines
For daily news stories, visit www.NewScientist.com/news
60SECONDS
symptoms in buffalo, but can trigger abortions in cows. Over the past few weeks, around 525 straying buffalo have been corralled along the park's borders. Almost half have tested positive for brucellosis and are the first up for slaughter. The Buffalo Field Campaign maintains that the risk of disease transmission is low. The group says "relatively few" susceptible cows graze in the spillover area outside the park. The campaigners were overruled on Monday, when US district judge Charles C. Lovell gave the slaughter the go-ahead. They will be launching an appeal.
Return of the king
Canada and the US, which devastated their numbers. "These figures are encouraging, because they show a trend toward recovery after a record low," says Omar Vidal, director ofWWF Mexico. Vidal says that the illegal logging
FIRST the good news: North America's monarch butterfly (Dana us plexippus) has bounced back after its worst year ever. Now the bad: it is still the fourth worst year since records began in 1993. WWF Mexico's latest survey of "Monarch butterfly the butterfly's Mexican heartland numbers were devastated shows that the insects wintering by storms during their there since November colonised migration i n 2009" 4 hectares of forest, over double the area occupied last year. The which threatened the monarch's area occupied is used as an indirect habitat is now under control, but measure ofbutterfly numbers. climate change and farming in In 2009, the butterflies faced the US could deplete the food the storms as they migrated from butterflies rely on en route.
Fake Mars shi p lands MarsSOO has landed. On 14 February, three crew members from the simulated mission to Mars stepped out ofthe windowless mock spaceship where they have spent the past eight months, and into a small room with a sandy floor and twinkling lights. After two more "Mars walks", they will be reunited with the other three crew members and start the eight-month "journey" back to Earth.
Portraits of a comet Early on 15 February, NASA's Stardust spacecraft flew past comet Tempell, taking 72 pictures of the potato-shaped object. When New
Drunk on nothing
Van Gogh's darkening yellows
THE US government's health department has a drink problem. The blood and urine tests used to identify drinkers can falsely finger teetotallers too. Typically the body destroys alcohol within hours, so the tests pick up substances that are formed in the process. But recent research shows that non-alcoholic wine or even bananas can push concentrations of the substances to levels associated with drinking. The health department's Substance Abuse and Mental Health Services Administration (SAMHSA) is aware of the problem and since 2006 has declared as "scientifically unsupportable" any legal or disciplinary action based solely on the test. But lawyers are now asking the agency to go further. "Can SAMHSA set a cut-off level which will reliably exclude accidental exposure [to alcohol] ?" asks William Meyer of the National Association of Drug Court Professionals. Greg Skipper of the Alabama Physician Health Program thinks not. But he says that new research suggests a different breakdown product called phosphatidyl ethanol can more reliably distinguish accidental exposure from deliberate drinking.
IT'S enough to drive an Impressionist
Paint from one tube turned brown,
Scientist went to press, the close
ups had not been released. NASA hopes to compare them with snaps
mad. A yellow pigment developed in
and in this sample the chromium in
taken by the Deep Impact mission
the 19th century was a gift to Vincent
the lead chromate at the surface had
to Tempell in 2005.
van Gogh: it helped him create his
been reduced from a VI oxidation
vibrant sunflower paintings. But
state to the darker Ill state.
since then some chrome yellow paint
Paint flecks from two restored van
Co l d c u re To banish an impending cold, take a
has darkened considerably - and no
Gogh paintings - Banks of the Seine
zinc supplement at the first sniffle.
one knew why.
and View of Aries with Irises- had
A review of 15 trials showed zinc
A team led by Koen Janssens at the University of Antwerp, Belgium, used
barium sulphate in the darkened
administered in syrup, lozenges or tablets within 24 hours of symptoms
a powerful X-ray beam generator at
areas. This white substance, which was used to make expensive paint go
the European Synchrotron Radiation
further or make the yellow paler, may
severity and length of illness, possibly
Facility in Grenoble, France, to
have helped reduce the chromium
through zinc's antiviral properties
analyse samples of the key pigment
and caused the darkening under light.
in chrome yellow - lead chromate from three 100-year-old tubes of
'The mixture of sulphate and
appearing significantly reduced the
(The Cochrane Library, DOl: 10.1002/
14651858.CD001364.pub3).
chromate is very sensitive to
the paint (Analytical Chemistry, DOl:
darkening under UV light. Galleries
10.1021/ac102424h). They then
should keep paintings containing
artificially aged it using UV light to
chrome yellow out of any strong light
simulate exposure to daylight.
or UV light" says Janssens.
Sto l en DNA Around 1 in 10 gonorrhoea bacteria include a small chunk of human DNA in their genetic make-up - the first time DNA has been found to have jumped from a mammalian genome to a bacterial one. What role, if any, the human DNA performs in the bacterium remains a mystery (mBio, DOl: 10.1128/mbio.OOOOS-11).
The power of one brain In 2007, all the general computers in the world could together perform 6.4 x 1018 instructions per second. That roughly equals the number of nerve impulses produced by one human brain each second (Science, DOl: 10.1126/science.1200970).
19 February 2011 1 NewScientist IS
THIS WEEK
What's next for Watson? A bright future awaits IBM's supercomputer after taking on humans in the TV quiz show jeopardy! jim Giles
involve puns and clues-within clues, and cover a vast range of topics, from science to pop culture. The show demands an encyclopedic knowledge, and Watson is up against the two most successful players ever to appear on Jeopardy!.
A MEDICAL robot; a Google-killer; a financial adviser; a tool for trawling legal documents; an aide for the intelligence services. These are just some of the careers that could be in store for Watson, a supercomputer created by IBM which this week "Watson has a huge challenged human knowledge and memory, loaded with intelligence in a three-part special 200 million pages of text from encyclopaedias" edition of the US quiz Jeopardy!. As New Scientist went to press, Instead of creating new the outcome of the pre-recorded final was still a carefully guarded algorithms to allow Watson to secret. But however it performs, understand/eopardyl's complex the fact that a machine is able questions, IBM's team threw to compete on Jeopardy! "is a everything they already had at the problem. The result is a system remarkable achievement", says Boris Katz, an artificial intelligence that runs all the best existing researcher at the Massachusetts algorithms for understanding Institute of Technology. and answering questions. Led by David Ferrucci, the When IBM first suggested a Jeopardy! machine four years team also gave their machine ago, many AI researchers were a huge memory, which they doubtful the company would loaded with 200 million pages of text from encyclopedias and succeed. Computers are great at newspapers, alongside custom following clearly defined rules, made databases of facts. but Jeopardy! questions can
To answerJeopardy!'s questions, Watson first guesses the subject. It knows, for example, that the word "this" often precedes the subject. So if a question begins "This 19th-century novelist. ..", Watson primes itself to search for authors.
Once it has worked out what it is looking for, Watson searches its databases for the answer. Its processor array is 2000 times more powerful than a desktop computer, allowing it to find thousands of possible answers in less than 3 seconds.
S ilicon su periority There is a long history of human-versus-machine match-ups and the results make for depressing reading if you are human.lt started in the 18th century, when a chess-playing robot toured Europe, beating many in its path.lt turned out to be a hoax: the "robot" was operated by a concealed human. The reprieve was short-lived, however
1979 BKG9.8 World backgammon champion Luigi Villa suffers a humiliating 7-1 defeat at the hands of BKG 9.8
1994 CHINOOK 1986 MAVEN MAVEN beats top Scrabble players. Its creator, Brian Sheppard, improves the software, and by 2002 it can think many moves ahead, something human players find difficult
Chinook wins world checkers (draughts) championship. Thirteen years later, its creators say they have simulated every realistic game of checkers and developed a system that means Chinook can never lose a match
6 1 NewScientist 1 19 February 2011 HotMags - Hot Magazines
1997 DEEP BLUE World chess champion Garry Kasparov loses to IBM's Deep Blue. Computers are now considered superior to even the strongest human chess players
In this section
• Andean settlers' cancer-fighting secret, page 9 • Periodic table of shapes, page 12 • Augmented reality helps police track suspects, page 26
To work out which ofthese is the correct answer, Watson uses 100 different tests to rate its confidence in each answer. Some tests check for wordplay. Faced with a question about an "arresting landscape painter", for example, Watson looks up
2008 POLARIS
Polaris narrowly defeats a line-up of big-name poker players in a series of one-on-one games in Las Vegas. For now, however, humans still have the upper hand: Polaris struggles in games that involve multiple players
meanings of " arresting" and checks for any connection with the names of landscape painters. Linked answers - in this case, "Constable" - get a higher confidence score. Watson settles on the highest-rated answer and tries to buzz in. None of the tests represents a breakthrough in language processing, but by combining them all Watson has leapt ahead of rival question-and answer systems. Watson is not designed just to play game shows, however. It could help with any task that involves quickly processing information in a large number of text documents. Take the medical profession. Although IBM won't reveal details of its plans to commercialise Watson's software, it has said that it is working with researchers
at Columbia University in New could "learn" by searching for new York on a medical application. documents to add to its database, If Watson's memory were filled and so would automatically with databases of medical update its search results as new literature, and combined with facts emerge. Prem Natarajan voice-recognition technology, it of Raytheon BBN Technologies could listen in on patient-doctor in Boston, one of the companies conversations, then search its involved in the DARPA project, databases and suggest possible compares this application diagnoses, each with its own to an oracle. confidence level. "Such systems could augment "Even Watson can make healthcare," says Amar Das of silly mistakes. We're not done yet. We've not even Stanford University in California, scratched the surface" who is helping a team at the nearby PARC research labs develop an AI system able to The Watson team have also answer doctors' questions about spoken to lawyers about a possible HIV treatments. These systems use for the machine. Lawyers have "great potential", he says, often have to sift through but medical language could pose mountains of documents when problems. Doctors in different preparing a case- something fields can use the same term to Watson could make easier. It mean slightly different things, could even improve the service for example. Watson would of staff at banks or insurance have to be trained to put terms companies, by helping them track in context and extract the down the answer to a question correct meaning. more rapidly. Intelligence services might also Thankfully, perhaps, Watson have a use for Watson. Members isn't infallible : it can find simple of the IBM team are part of a questions baffling. This is in part machine-reading research because the software relies programme funded by the US heavily on finding text that looks Defense Advanced Research like the right answer to a question. Projects Agency (DARPA), based As a result, it misses out on in Arlington, Virginia. information that is deemed by DARPA is interested in humans to be too obvious to write machine reading in part because down. Not only that, but Watson intelligence analysts are faced sometimes thinks that fictional characters are real, says Gondek: with far more reports than they can synthesise, says Eric Nyberg, it once named the first woman in of Carnegie Mellon University in space as "Wonder Woman". Pittsburgh, Pennsylvania, who is To get a grip on such common working with the Watson team. sense issues, Watson will need Instead of having to study every to improve its understanding of report, analysts could use Watson the questions it is asked, rather to extract information on, say, than just searching for answers how individuals discussed in the that look plausible - a much documents are linked. bigger challenge. Watson's potential also extends "Watson is an awesome to everyday tasks. It is not currently machine," says Katz. "But connected to the internet, but if it sometimes it makes amazingly were, it could improve its search silly mistakes. That should tell results. "Watson could replace researchers that we're not done. Google for some kinds of We've not even scratched searches," says Nyberg. the surface." • See how Watson fared in the Like a human brain, a Watson final at our technology blog search engine would continually add to its knowledge. The software newscientist.com/onepercent 19 February 2011 1 NewScientist 1 7
THIS WEEK
Fly sniffs chemical's quantum vibrations can dictate its odour, and came up with an explanation of how this might work. His idea was that electrons might only be able to pass across a receptor if it was bound to a molecule that vibrated at the right frequency. Ordinarily, the energy needed for the electron to make this journey would be too great, but the right vibrational energy could prompt a quantum effect in which the electron "tunnels" through this energy barrier, and this would then be detected and registered as a particular smell. Ifthis is correct, animals should
Rachel Courtland
HOW does a nose generate the signals that the brain registers as smell? The conventional theory says it's down to the different shapes of smelly molecules. But fruit flies have now distinguished between two molecules with identical shapes, providing the first experimental evidence to support a controversial theory that the sense of smell can operate by detecting molecular vibrations. The noses of mammals and the antennae of flies are lined with different folded proteins that form pocket-shaped "receptors': It has been generally assumed "At the outset, I never that a smell arises when an odour thought it could work. During the experiment, molecule slides into a receptor we convinced ourselves" like a key in a lock, altering the receptor's shape and triggering a cascade of chemical events that be able to distinguish between eventually reach the brain. But molecules ofthe same shape but this "shape" theory has limitations. with bonds that vibrate at different For one, it can't easily explain why frequencies. That is the case for different molecules can have very chemicals in which atoms of deuterium - a hydrogen isotope similar smells. In 1996, biophysicist Luca whose nucleus contains a neutron Turin, now at the Massachusetts as well as the normal proton Institute ofTechnology, proposed replace ordinary hydrogen atoms. a solution. He revived a theory The extra neutrons don't change that the way a molecule vibrates the molecule's shape, but they
Same shape, different smell The fragrant acetophenone molecule fits into a particular protein receptor like a key in a lock. Replacing the hydrogen atoms with deuterium atoms alters the rate at which the molecule vibrates. This may change the energy needed for an electron to tunnel across the receptor, altering its response and hence the perceived smell
HYDROGEN 1 proton/1 electron
.---·····
( •
\! \..... /
DEUTERIUM 1 proton/1 electron/1 neutron
�-----.\
1.... ..) -
double the mass of the hydrogen atoms and so alter the frequencies at which the molecule vibrates. Past tests on humans failed to turn up strong evidence that people can distinguish normal odour molecules from their "deuterated" counterparts. But now Turin has teamed up with Efthimios Skoulakis ofthe Alexander Fleming Biomedical Sciences Research Center in Vari, Greece, to test the idea on fruit flies, which can easily be trained to recognise different odours. Their team initially placed fruit flies in a simple maze that let them choose between two arms, one containing a fragrant chemical such as acetophenone, a common perfume ingredient, the other containing a deuterated version. If the flies were sensing odours using shape alone, they should not be able to tell the difference between the two. In fact, the researchers found that flies preferred ordinary acetophenone. They also showed a preference for ordinary versions of octanol and benzaldehyde over deuterated versions. The team also found they could use mild electric shocks to either reinforce or reverse this general preference for non-deuterated molecules (Proceedings of the National Academy ofSciences, DOl: 10.1073/pnas.1012293108). This suggests the flies may be able to sense the vibrations characteristic of the bonds linking deuterium to carbon atoms. "At the outset, I thought this could never work," Skoulakis says. "During the course of the experiment we convinced ourselves." Turin sees the results as a "vindication" of his theory, at least in flies. "My theory was described as impossible physically, implausible biologically, not supported by evidence," he says. "This is a clear indication that some component of fruit fly olfaction is sensing vibrations." The experiment "really supports this idea that fruit flies have the ability to be quantum
8 1 NewScientist 1 19 February 2011 HotMags - Hot Magazines
detectors", says Gregg Roman of the University of Houston in Texas, who has just started studying isotope detection in fruit flies. How large a role molecular vibration sensing plays is unclear. Leslie Vosshall of Rockefeller University in New York City agrees that the experiment suggests fruit flies can distinguish between isotopes, but says the assumption that this is due to vibrations is an "over-interpretation". Turin's original tunnelling idea was based on a type of odour receptor in humans that fruit flies don't appear to have. "The logic of
For daily news stories. visit www.NewScientist.com/news
Little people hold a big cancer-fighting secret A HORMONE that gives a small
relatives, suggesting that individuals
population in the Ecuadorian Andes
with the condition rapidly dispose of
their short stature may reveal secrets
damaged cells before they are able
of thwarting cancer and diabetes.
to turn cancerous. Those with Laron
jaime Guevara-Aguirre at the
syndrome also had much lower levels
Institute of Endocrinology. Metabolism
of insulin-like growth factor-1 (IGF·1).
and Reproduction in Quito, Ecuador,
another hormone linked with the
and Valter Longo at the University
development of cancer. "They had the
of Southern California in Los Angeles
lowest values of IGF·1 ever recorded,"
studied a group of 99 people in the
says Guevara-Aguirre (Science
region for 22 years. These people all
Translational Medicine, DOl: 10.1126/
have a dimi nutive stature because
scitranslmed.3001845).
they have La ron syndrome - an
Studies in animals and centenarian
inability to make functional copies of
humans have shown that impaired
the human growth hormone receptor.
function of IGF·1 increases longevity.
Remarkably. none of the individuals developed diabetes, and
Although this wasn't seen in those with Laron syndrome, Guevara-Aguirre
only one developed cancer (which
is conducting further studies to see if
was cured). By comparison, among
there is in fact an effect. Most of the
1600 relatives without the condition
deaths among the sample population
5 per cent developed diabetes and
were from accidents, convulsive
17 per cent developed cancer,
disorders or abuse of alcohol, so he
suggesting that blocking the effects of the hormone might somehow protect against these diseases. The researchers found that levels of insulin in people with La ron
"Remarkably, none of the individuals developed diabetes, and only one developed cancer"
syndrome were just one-quarter of normal, primarily because their cells
is checking whether they might
were ultra-sensitive to it. so less was needed. This tallies with their lack
have lived longer without these
of diabetes. Remarkably. they all
The team says the protective
remained diabetes-free even though
effects against cancer and diabetes
most of them were obese. normally
match those found in mice unable to
a prelude to adult-onset diabetes. To better understand the anti·
vibrations. He suggests that using the fly to test the vibration theory escapes me," Vosshall says. giving mild shocks to humans, Turin and Skoulakis are planning which wasn't done in the previous experiment, may encourage their genetic studies that might help pinpoint the amino acids on brains to pick up on differences. receptors that play a key role in Experiments are planned in isotope detection. This could help another type of mammal. Several piece together a specific tunnelling years ago john Sagebiel ofthe mechanism for the flies' receptors. University of Nevada, and Mary Could humans differentiate Cablk of the Desert Research between isotopes? In 2004, Institute, both in Reno, found that Vosshall and her Rockefeller their pet dog, an Australian shepherd, seemed to be able to colleague Andreas Keller found that people could not distinguish tell apart ordinary acetophenone and a deuterated version. They are between acetophenone and its now applying for funding to see deuterated cousin. But Skoulakis says flies might be more sensitive if these informal results hold up to the effects of quantum in other dogs. •
other causes of premature death.
make the growth hormone receptor. "The convergence of data obtained in
cancer phenomenon, the researchers
the mice and humans is striking," says
exposed normal human breast cells
Andrzej Bartke at Southern Illinois
to extracts of blood serum from
University in Springfield.
people with Laron syndrome or their
The results may support the case
syndrome-free relatives. Compared
for trials of Somavert as a treatment
with breast cells exposed to blood serum from relatives, those doused
for cancer and diabetes. The drug was developed to block the growth
in serum from individuals with Laron
hormone receptor and it has been
syndrome had 30 per cent higher
used since 2003 to treat people with
levels of enzymes that are protective
acromegaly, who make too much
against cell damage, and much lower
growth hormone. But john Kopchick
levels of activity in genes known
at Ohio University in Athens, who
to promote tumour growth. Additionally, when these
developed the drug, warns against blocking the growth hormone in
"protected" cells were deliberately
healthy people because of possible
damaged with hydrogen peroxide
side effects . including cardiovascular
they died much faster than the
problems, low energy levels and
cells doused with blood serum from
weight gain. Andy Coghlan • 19 February 2011 1 NewScientist 1 9
THIS WEEK
Eye in the sky could watch out for floods Wendy Zukerman
SEVERE floods have hit Sri Lanka, Brazil, the Philippines and Australia since the turn of the year, while Pakistan is still feeling the effects of floods there last year. As La Nina settles in for the decade, such floods could strike all too frequently. An early warning system using satellites could help by making flood forecasting easier and more accurate. What's more, the seeds of a global monitoring system are already in place. The network of water gauges used to monitor rainfall and water height at the moment have drawbacks, says Jeff Walker at Monash University in Melbourne, Australia. "Gauges get washed away during flooding," he says. Worse, ground-based gauges can get mired in politics. Floodwaters do not respect international borders and if political tensions are running high, countries upstream of a flood may not pass on vital information to their neighbours downstream.
Shape-changing brain cells to blame for PMS
The answer could be satellites, which are already monitoring rainfall. The Tropical Rainfall Measuring Mission is a joint venture between NASA and the Japan Aerospace Exploration Agency. It provides data for a real time river forecasting model,
"late luteal" phase of their cycle and progesterone levels are high. To investigate potential
running in Bangladesh since 2006 (International Journal of Applied Earth Observation and Geoinformation, DOl: 10.1016/j. jag.2010.11.003). In 2013, NASA plans to replace the TRMM with the Global Precipitation Measurement Mission. Satellites can also monitor soil moisture, predicting when and where rain is likely to fall and when flooding is probable. Wetter soil releases more water through evaporation, which then turns into rain. But if soil is fully
However, in the late luteal phase
saturated, it absorbs no more water and a flood can develop. The ASCAT sensor on-board the European Space Agency (ESA) MetOp satellite system, launched in 2006, measures microwave radiation reflected back by the soil- the wetter the soil the more microwaves are absorbed. Last year, Wolfgang Wagner of the Vienna University ofTechnology, Austria, combined traditional forecast models with ASCAT data to improve run-off predictions in the floodplains ofltaly (Hydrology and Earth System Sciences, DOl: 10.5194/hess-14-1881-2010). The trouble is that MetOp operates on so-called C band microwaves, which have difficulty penetrating dense vegetation. In 2009, ESA launched the Soil Moisture and Ocean Salinity satellite, which operates in the L band. This can see through vegetation more easily - although it detects radiation in 40-kilometre patches; too coarse for detailed flood forecasting. In future, a global monitoring system would include information from satellites and sensors on the ground. Xiwu Zhan at the US National Oceanic and Atmospheric Administration, is working on one such system but it might not be in place for at least a decade. •
emotion and behaviour. Changes to
women with PMDD had heightened
the receptors make them less
activity in their cerebellum. The
receptive to a chemical called GABA.
mechanisms behind PMDD, Andrea
larger the spike in activity, the worse
Rapkin at the University of California,
the symptoms. Women without
GABA is the brain's main inhibitory molecule. One of its functions is to
Los Angeles, used positron emission
PMDD had no such spike, even though
limit brain activity associated with
"ARE your GABA receptors playing
tomography to scan the brains of 12
their progesterone levels were also
stress and anxiety.
up?" It seems that these brain cells
women with PMDD and 12 without
high (Biological Psychiatry, DOl:
are to blame for premenstrual
the condition, at various times
10.1016/j.biopsych.2010.09.029).
syndrome (PMS) - the mood swings
throughout their menstrual cycle.
some women experience before their period starts. Many women feel a little irritable around this time, but up to B per cent have extreme symptoms, including
Before each scan, the women rated
Animal studies have shown that
Rapkin suggests that in PMDD, progesterone alters the shape of GABA receptors in the cerebellum,
progesterone can change the
making it harderfor GABA to bind to
the severity of any symptoms they
shape of receptors present in the
them and damp down anxiety.
might have. Blood samples were also
cerebellum, which forms connections
taken to test their hormone levels. Fluctuating hormones were not to
with brain areas responsible for
anxiety and fatigue. Symptoms of
blame: all the women experienced
so-called premenstrual dysphoric
similar jumps in progesterone levels
disorder (PMDD) begin around a week
throughout their cycle, irrespective
beforehand when women are in the
of whether they had PMDD or not.
"Women with PMS may have GABA receptors that are particularly sensitive to progesterone"
10 I NewScientist 1 19 February 2011 HotMags - Hot Magazines
Lorraine Dennerstein at the University of Melbourne, Australia, suspects women with premenstrual syndromes have GABA receptors that are particularly sensitive to progesterone, and so change shape easily. Wendy Zukerman •
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d y think that the cosmos is a little like my bowl of soup. 19 February 2011 1 NewScientist 1 39
I wipe my soup bowl clean and shudder as I recall a study that showed that about 100 million bacteria lurk in a typical dishcloth. Many are rod-shaped bacteria that originate from faeces. In fact there are more faecal bacteria, such as Escherichia coli and Klebsiella, in my kitchen sink than in the toilet bowl after I flush it. "That's probably why dogs drink out of the toilet," jokes Chuck Gerba at the University of Arizona in Tucson {Journal of Applied Microbiology, vol 85, p 8tg). The culprit is mostly bacteria originating from raw meat. "These bacteria enter via the food supply and then multiply in the wet and moist environment in the kitchen," says Gerba. My sink carries the ultimate domestic biological weapons. "The object in the house with the most faecal bacteria and total bacteria is the kitchen sponge or dishcloth." Gerba advises me to make liberal use of bleach. 8.2opm
8-4opm As I settle to watch a DVD of Apocalypse Now, I remember an old friend telling me that Francis Ford Coppola's masterpiece on the Vietnam war actually contains more continuity errors than any other movie he could think of. I still struggle to spot any ofthese howlers at all. Why? This is a prime example of"change blindness", according to Dan Simons of the University of Illinois at Urbana-Champaign and co-author of The Invisible Gorilla (Harper Collins, 2010 ). "Many people are convinced they regularly notice such errors," he says, but in reality, we actually notice very few ofthem. Simons has gathered some remarkable evidence to show that it is possible to look at something without seeing it. In one experiment he carried out with Daniel Levin of Vanderbilt University in Nashville, Tennessee, a stranger asked people walking across a college campus for directions. During the resulting conversation, two men carrying a wooden door passed between the stranger and the subjects. Half of those tested failed to notice that as the door passed, the stranger had been replaced with a man wearing different clothes and of a different height and build. My change blindness occurs because it is not possible to perceive and remember all of the details of the world around me. Many howlers in films are continuity errors where items in one scene disappear, move or change colour in subsequent scenes. In the case of Apocalypse Now, perhaps my limited visual memory did not retain enough details between scenes to reveal the howlers, never recorded them in the first place, or simply did not compare them.
Even without the d i rty dishes, it is filthier than a freshly flushed toilet
11.2opm Before I go to bed, I pick up an old
issue ofNew Scientistto help research this feature. I think that both of my eyes focus on one part of the text but, in fact, my right and left eyes often focus on different parts of words, according to psychologist Simon Liversedge at the University of Southampton, UK, who has performed sophisticated eye-tracking studies. And although I think that my eyes are moving smoothly across the text, that is an illusion, he says: "When you read, you make a series of fixations interspersed with fast movements of the eyes called saccades." During a saccade my eyeballs swivel by between 2 and 5 degrees, over an interval of 30 to so milliseconds. The fixations that I use to read take up to 250 milliseconds (Psychological Bulletin, vol 134, p 742). My brain suppresses the confusing blur of words during a saccade, only collecting visual information at the start and end. It then integrates these snapshots to provide me with the sensation of a "smooth flow" of words and delivers them to my language processing system, via the visual cortex at the back of my head.
40 I NewScientist 1 19 February 2011 HotMags - Hot Magazines
M.•tcwlA-4' . M.A �a.-- aJ 11.40pm Editing my vision is notthe only way my brain tricks me during my bedtime reading. Even though I have two eyes, and so two views of the page, I only perceive one world. To achieve this Cyclopean view, my visual system must coordinate the input of the two eyeballs precisely and systematically and then process it, says Mark Changizi, director of human cognition at the 2AI Labs in Boise, Idaho, and author of the Vision Revolution (Ben Bella, 2009 ). This is easy for me to investigate. I shut one eye and see that my nose alone takes up a considerable portion of my view. When I re-open that eye, it becomes obvious that my nose is actually transparent - I can gaze through it to the world beyond. In fact, says Changizi, I am seeing the future too. From the time light hits my eye, it takes one-tenth of a second for the brain to perceive it. "Your brain actually generates a perception of what the world will look like in a tenth of a second. You don't see reality but a construct, one which evolved to help you to survive."
"Even though I'm lying motionless, I'm hurtling at great speed through the cosmos"
11.45pm While I sit in bed and stir my bedtime cocoa, armies of microscopic machines in my body go marching. The machines are a family of protein motors called myosins that turn chemical energy into motion. Inside my nerves, for example, myosin V walks around on two "legs" along tracks called actin filaments, though their 74-nanometre stride is less than a 10-millionth of my own. In my muscles, myosin II forms filaments of around 300 molecules which also walk, like a millipede, along the actin filaments to make my muscles contract. Each myosin molecule can develop a force of a couple of piconewtons this way, according to Robert Cross at the University of Warwick in the UK. "Lifting a 40-gram spoon means that in your arm an additional two million million myosin molecules are working as a team," he says. Many more molecular machines take part in the serious business of keeping me alive, to open and close my eyelids, dilate my irises, help me to hear by sensing the motion of hair cells in my inner ear and, as I yawn, squeeze air out of my alveoli to move my vocal chords to generate a satisfied sigh.
11.55pm As I stretch and yawn before I succumb to sleep, I remember that there are plenty of ideas around to explain why I yawn. They include brain cooling, improving attention by helping us draw in more oxygen, synchronising our mood with others. Another suggestion is that baring teeth during a yawn evolved as a way of protection from predators intent on ambushing a drowsy foe. There are many more. No one is sure which explanation, or combination of explanations, is the right one. I close my eyes, satisfied that deeper understanding does not diminish life, but instead amplifies my sense of awe. • Roger Highfield
is the editor of New Scientist
19 February 2011 1 NewScientist 1 41
The photosynthetic machinery i n p lants is hopelessly outmoded . U pdating it could boost yields to u n precedented levels, as Bob Holmes d iscovers
B l I on -yea r u pg rade 42 1 NewScientist 1 19 February 2011 HotMags - Hot Magazines
F
Food production has been hit by heatwaves and floods
OOD
prices are at an all-time high right now. And although they are unlikely to stay that way, the long-term outlook is clear. From an increasingly rich population in Asia demanding more meat to the weather growing ever wilder, there are many reasons to think the days of cheap food are over. So the focus is once again turning to ways to boost crop yields, just like so years ago, and a few biologists have grand plans for achieving this. Instead of tinkering around with the body, like conventional breeders, they want to upgrade the engine. Plants pirated the machinery they use for photosynthesis from bacteria more than a billion years ago. The same machinery is found in every single plant today, from tiny insect eating sundews to colossal redwood trees- and it has barely changed. For all the architectural complexity that plants have evolved, they are still powered by the same engine they have had from the beginning. That's a bit like building a modern aircraft carrier and powering it with a Victorian steam engine. By contrast, while photosynthetic bacteria don't look like they have changed much, some have made big improvements under the hood. They can convert carbon dioxide into food far more efficiently than most plants, and many are also able to make their own nitrogen fertiliser. If crop plants could be upgraded with just some of the improved machinery found in modern bacteria, agriculture could be revolutionised once again. The story begins about one-and-a-half billion years ago, when photosynthetic bacteria were enslaved by a more complex cell. The descendants of those bacteria lost their ability to live independently and evolved into the cellular solar power stations known as chloroplasts. There is one amoeba whose "chloroplasts" evolved from a modern cyanobacterium around 6o million years ago, but the chloroplasts in all algae and plants derive from a single ancient cyanobacterium. Why does this matter? Think ofthe countless cyanobacteria living in the sea. If a mutation enables one cyanobacterium to photosynthesise more efficiently, it will grow
and reproduce faster, and its descendants could come to dominate a population within weeks. The rampant gene-swapping among simple cells means other kinds of bacteria could acquire this trait too. Now suppose that same mutation occurs in a chloroplast in a plant. It might not be beneficial in plants, as what is good for chloroplasts can be bad for the host cell. Even if the mutation is beneficial, the odds are the chloroplast is in a leaf that will fall to the ground and die. And even if the mutation occurs in a cell that eventually gives rise to a new plant, the much slower reproduction rate of plants means it will take many decades for the mutation to spread through a population. These differing rates of evolution perhaps explain why, as levels of carbon dioxide in the atmosphere fell over the past billion years, cyanobacteria evolved an elegant means to adapt to this change, while plants only managed a costly compromise.
Primordial air Plants need C02 for making food via photosynthesis. They add this C02 to another molecule, using an enzyme called rubisco, and by doing this over and over again, plants acquire the carbon needed to make sugars, proteins and fats. When photosynthesis evolved around 2 billion years ago, the Earth's atmosphere contained lots ofC02 and no oxygen. It did not matter that rubisco is in fact happy to grab either C02 or oxygen- and when it grabs oxygen it destroys food instead of making it. As C02 levels fell and oxygen levels rose, though, this unwanted reaction became ever more common, making photosynthesis less and less efficient. As rubisco's wayward tendencies became a serious handicap, cyanobacteria evolved a way to increase C02 levels within their cells up to a thousandfold, recreating the ancient C02-rich atmosphere rubisco evolved in. They do this The solar power stations in cells are the descendants of ancient bacteria
19 February 2011 1 NewScientist 1 43
'These a re seri ously a m b itious schemes fo r boosti ng food p ro d u cti o n . We've g ot to try them"
CHAM BERS OF S ECRETS The textbooks will tell you that bacteria are not much more than bags of chemicals. In fact, many contain protein-walled microcompartments. By concentrating chemicals in these reaction chambers, the speed of certain processes - such as capturing C02 during photosynthesis (see main story) - can be greatly increased. Microcompartments can also protect cells by keeping toxic by-products contained until they can be converted into harmless forms. They are essentially tiny factories within cells - and their potential is making big industries pay attention. Researchers have already begun creating bacteria with customised microcompartments designed to carry out novel reactions. For example, Todd Yeates, a structural biologist at the University of California at Los Angeles, is trying to encapsulate all the enzymes required to produce butanol, a potential biofuel. This should help keep intermediate products in the pathway from leaching away and so increase the reaction's efficiency, he says. Martin Warren at the University of Kent has already achieved this with another simple biofuel, though he is unwilling to give further details until the work has been published. Our imagination is the only limit on the possibilities, Warren says. "I don't think people have realised just how easy and manipulatable these things are."
by putting the enzyme inside tiny internal compartments called carboxysomes. Unlike the membrane-bound organelles found in plant and animal cells, these microcompartments are made out of proteins and have regular geometrical shapes, like the shells of viruses. The beauty of carboxysomes is thatwhile it is difficult for C02 to escape from them, bicarbonate ions - formed when C02 reacts with water - can diffuse in. Inside them is another enzyme, carbonic anhydrase, that converts bicarbonate back into C02• C02 levels in carboxysomes are boosted still further by transport proteins in the outer membranes of the cyanobacteria. These actively pump bicarbonate ions and C02 into the cell. Most likely, cyanobacteria evolved these mechanisms just 400 to 350 million years ago. The amount of C02 in the atmosphere plummeted during this time, as plants spread across the land. Green plants took another direction. They evolved a slightly different form of rubisco that is less likely to grab oxygen. The catch is that it also works far more slowly, so plants have to pack their chloroplasts with vast quantities of the enzyme to keep photosynthesis ticking along at a reasonable rate. A quarter ofthe nitrogen plants need is used just to make rubisco. "Crop plants may have missed the boat in terms of getting some of the advanced carbon-dioxide-concentrating mechanisms that cyanobacteria have," says Dean Price, a plant molecular biologist at Australian National University in Canberra. Some plants have evolved something similar, though, although it is not as efficient. In the past 20 million years or so, as levels of C02 fell to new lows, a few found a way to concentrate C02 using a process called C4 photosynthesis. Two important crops, maize and sorghum, are C4 plants, and a big effort is now under way to transfer this trait to other crop plants such as wheat and rice (New Scientist, 14 September 2010, p 40). Price and his colleagues are taking a different approach. They are now working to upgrade the chloroplasts of crop plants with cyanobacterial innovations. The quickest way to do this is just to add some of the bicarbonate pumps to chloroplasts. In plants, C02 merely diffuses through the chloroplast membranes, so active chloroplasts can have 20 per cent less C02 than the rest of the cell. Two of the pumps, SbtA and BicA, are each encoded by a single gene and so should be relatively easy to transfer. "We think it's doable," Price says. "It's just a matter of having enough funds to try enough options."
44 1 NewScientist 1 19 February 2011 HotMags - Hot Magazines
If Price and his team succeed - and he thinks they will within three years - that single small upgrade could boost photosynthetic rates by between 15 and 25 per cent, he calculates. "These are the sorts of numbers that make plant breeders quite interested," he says. "They're interested in 3 to 5 per cent, so if we can get 15 per cent, that would make a big difference."
Grand goal The grander goal is to engineer the whole carbon-concentrating mechanism of modern cyanobacteria into chloroplasts. This would involve adding at least eight or nine genes to chloroplasts: about five for the proteins that form the carboxysomes themselves, plus those for transport proteins and carbonic anhydrase. They might also have to add the bacterial version ofrubisco and turn off carbonic anhydrase elsewhere in the chloroplast, to prevent it from turning hard won bicarbonate into C02 before it gets into carboxysomes. "There's a lot that has to be just right for this to work," Price says. "Some of the proteins are required in very small amounts and others in very large amounts. It's a question of getting all those balances right." In theory, though, it is simpler than converting plants to C4 photosynthesis, which might require tweaks to hundreds of genes. Price's team is starting by adding carboxysomes to the lab favourite, the Escherichia coli bacterium, which is easy to work with. Once they have done that, they will try to do the same with another lab standard, tobacco. Only then will they be ready to try it in crop plants. "It could happen very quickly or it could take a long time," Price says. So far, nobody has built a carboxysome from scratch. But Martin Warren, a synthetic biologist at the University of Kent, UK, and his colleagues have assembled another kind of protein microcompartment from scratch in E. coli. They have even managed to get the cell to deliver a fluorescent jellyfish protein to their construct and plan to use their tailor-made microcompartment to carry out industrially important reactions (see "Chambers of secrets", left). Their success strongly suggests that building a carboxysome is also feasible, says Warren. "I don't see it as being problematic. If anything, it should be slightly easier, because there are fewer subunits," he says. Some people are not so sure, however. Perhaps the reason green plants have never
Record spikes in food prices have contributed to unrest in many countries in the past two years
at the University of California at San Diego. What is understood, though, is how bacteria fix atmospheric nitrogen, so genetic engineers are now considering adding the genes involved directly to plants. The chloroplast is the obvious place to put them. For one thing, cyanobacterial nitrogen-fixing genes might work best in this setting. "You're essentially putting bacterial genes in a bacterial system," says Eric Triplett, a microbiologist at the University of Florida in Gainesville.
juggling act
Record h i g hs The prices of basic foodstuffs are expected to fall from the current peak by 2012, weather and harvests allowing, but the underlying upward trend looks set to continue 250
The food price index composed by the UN Food and Agriculture Organization represents the price countries pay to import basic foodstuffs, adjusted for inflation
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evolved anything like carboxysomes, says Andreas Weber, a plant biochemist at Heinrich Heine University in Duesseldorf, Germany, is that they do not work in plants for reasons we may be about to discover. Weber is optimistic about the prospects for another kind of upgrade -changing how plants obtain nitrogen. The element is vital for making protein and thus for growth, but most plants can only get nitrogen by absorbing whatever nitrogen compounds happen to be in the soil. This is why farmers usually have to add expensive nitrogen fertilisers, which damage the environment in many ways, including by increasing
emissions of a potent greenhouse gas called nitrous oxide. If crops could get nitrogen directly from the atmosphere instead, like some groups of bacteria and cyanobacteria, the benefits would be huge. Of course some plants, notably beans and peas, already exploit nitrogen-fixing bacteria by housing them in nodules in their roots. Can't we just get these symbiotic bacteria to associate with a wider range of crops? The problem is, no one is sure how to achieve this. "It would take a long time to understand all the genes necessary to have a symbiotic association with a higher plant," says james Golden, a molecular microbiologist
Better still, chloroplasts already produce several enzymes closely related to those used in nitrogen fixation. Borrowing these components could greatly reduce the number of genes that need to be added to just eight or so. "That's still a lot, but it's less than the 20 we used to think," says Triplett. The catch, and it's a big one, is that the key enzyme in the nitrogen-fixation reaction nitrogenase - is destroyed by oxygen, yet photosynthesis produces oxygen. The problem is so serious that in some filament forming cyanobacteria, one in every 10 cells or so turns off photosynthesis and specialises in fixing nitrogen- a rare step towards multicellularity in bacteria. However, a few bacteria, such as Azotobacter, perform a more delicate juggling act. They fix nitrogen at night and during the day they chemically convert their nitrogenase to an inactive form that is not destroyed as oxygen levels rise during the day. It might be possible to attach a molecular "timer" to nitrogen-fixing genes that could then be inserted into a chloroplast, Golden says. Alternatively, the genes could be activated only in root tissues where photosynthesis does not occur. The possibility of creating crop plants that produce their own fertiliser in this way is more than just idle speculation. At least one major company is already trying to engineer nitrogen-fixing enzymes into crop plants, says Ray Dixon, a molecular biologist at the john Innes Centre in Norwich, UK, though he cannot reveal any details. The billion-year upgrade is a few years away at best, but if it happens, the pay-off could be as great as that of the Green Revolution in the 1960s. "These are seriously ambitious schemes," says Dixon. "You've got to try them." • Bob Holmes is a consultant for New Scientist based in Edmonton, Canada
19 February 2011 1 NewScientist 1 45
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46 1 NewScientist 1 19 February 2011 HotMags - Hot Magazines
Keeping up e-ppearances Resto ri n g you r reputation i n the i nternet age can feel i m possib le. So how ca n you go a bout it asks Sally Adee
HE mistake that left my online reputation in tatters began with some innocent office banter. It was 2003, and I was working as an office drone. Bored out of our minds, a colleague and I gossiped over email about the goings-on in the women's restroom. (I'll spare you the details.) Tickled by the exchanges, my partner in crime published the emails on her friend's website. We soon forgot about it. Four years later, I qualified as a journalist and began to build what I hoped would be a Pulitzer-studded career. Then, one day, in an act of narcissism all too common among journalists: I googled myself. And my heart stopped. Instead oflinks to stories I had written, I saw a list of pornographic websites. Further investigation revealed that our juvenile exchange about the women's restroom had proved titillating to an unexpected audience, and had found its way onto a coterie of fetish sites. Goodbye Pulitzer. My situation was uniquely humiliating, but I am not alone in feeling helpless about how my identity is presented online. Most people have stumbled across nasty surprises about themselves on the internet, be it an embarrassing photo, a record of a youthful indiscretion or even an entirely false claim. Thankfully, there are ways to restore your online reputation. While you might think that reducing your internet presence is the way to go, you'd be wrong. The key to managing your reputation is to spend more time online, not less. The advocates of this approach argue that polishing your online persona could soon join healthy eating and exercise in your arsenal of everyday life-maintenance chores. So how exactly do you go about it? We have been cultivating our social status ever since our primate ancestors picked bugs
T
off each others backs to curry favour. The advent of the internet has made managing our reputation a lot harder, however, not least because it has transformed the way information about us circulates within our social circles and beyond. Consider, for example, an experiment designed to explore how much information people are willing to share online, which was conducted by a team led by Bernardo Huberman of the Information Dynamics Laboratory at Hewlett-Packard Laboratories in California. He set up a mock auction, but with a twist. Participants had to bid to persuade others in their group to reveal their true weight something which many people would rather not confess to freely. Huberman found that low bids were more likely to be accepted when the bidder was a similar weight (IEEE Security
•••••••••••••••••••
"We are losing our abil ity to present separate selves o n l i ne, something many of us haven't adapted to yet" and Privacy, DOl: 10.nog/MSP.2005.137). The message? If you think you are among peers, you will share details you might normally consider private. Though Huberman's experiment wasn't online, it is salient for online social networks, where it can feel like you are only conversing with close peers. Yet this is often illusory. Many of us share highly personal information over the internet without appreciating that it could reach a much wider audience, and is very often permanent. In the real world, we can compartmentalise our
separate identities: you can have one identity at work and another when socialising at the pub with friends, for example. Such boundaries disappear online, however. The cross-pollination of all our different selves is known as context collapse among social scientists, says Alice Marwick of Microsoft Research New England in Cambridge. We are losing the ability to present these separate selves online, something many of us haven't adapted to yet. For some very unlucky folk, the fallout has been public and unpleasant (see "Bad Reputation", page 49) Maybe the solution is to stay anonymous online. After all, if you hide behind a pseudonym like Spacegirl, you are safe, right? Not always, says Paul Resnick, a computer scientist at the University of Michigan in Ann Arbor who studies online reputations. .
Digital trail Resnick set u p a n experiment where participants could converse online under pseudonyms. He found that if people were told they were speaking anonymously, they were more willing to share extremely personal information - the kind that would negatively affect their reputation were it attached to their name. "They shared their weight, pictures of all the food they had eaten, and a lot of their struggles," he says. But such information can easily be linked to you, says Resnick. Consider the fate of the customers ofNetflix, a US online video rental firm. Film suggestions are Netflix's bread and butter; their movie recommendation program anticipates the wishes of customers. In 2006, the company launched a contest with a $1 million prize to find the best improvement to its system. Netflix gave the 51,000 entrants a database of half a million customers, which included people's rental history. Don't worry about customer privacy, said Netflix, we have anonymised it. To show Netflix's folly, Arvind Narayanan and Vitaly Shmatikov at the University of Texas, Austin, got the database and cross referenced it with reviews posted on the Internet Movie Database (IMDb). This allowed them to identify almost all of the names of specific individuals, and then infer things like political affiliation and sexuality from their movie choices. "Netflix wanted to make a better recommender engine," says Michael Fertik, who runs Reputation.com, a firm based in Redwood City, California, that manages online reputations. "And they just knocked a > bunch of people out oft he closet." 19 February 2011 1 NewScientist 1 47
Protect i n g yo u r v i rt u a l vi rtue Un less your case i s serious, improving your online reputation i s easier than you think
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START BY GOOG LING YO U RS E L
Nice work. You have no online presence
• • • • • • • • • •
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YES
Can you find your name on the fi rst page of the search results?
YES
