By Joseph Milton

That’s not fair

Overt inequality is distasteful to most of us and social scientists have long suggested that humans dislike perceived unfairness, based on behavioural and anthropological evidence. Now, for the first time, research published in Nature shows that neurons - brain cells- involved in the brain’s reward circuitry directly respond to the fairness of a situation.

John O’Doherty’s team at the California Institute of Technology monitored neural responses in the striatum and prefrontal cortex of participants who were paired up to take part in a monetary game.
One participant in each pair was given more money than the other. Both were aware of the disparity.

The team then selectively handed out more money, and found that neuronal activity was greater in the ‘high-pay’ people when money was given to the ‘low-pay’ person rather than to themselves. The opposite pattern of activity was seen in the low-pay participants.

Scent hormone vital for bonding identified

A key hormone which allows animals to form bonds with others through smell has been identified by researchers at The University of Edinburgh.

Vasopressin helps the brain differentiate between familiar and new scents, allowing animals to establish strong bonds. Many scientists think a failure in this recognition system in humans may prevent people from developing deep emotional bonds with others. A lack of scent based bonding could be at the root of conditions in humans such as some forms of autism and social phobia.

The study, published in the journal Nature, suggests that when the hormone fails to function, animals are unable to recognise other individuals from their scent.

The researchers reached their conclusion by studying rats. They placed an adult rat in an enclosure with a baby rat and left them to sniff each other.

After a short separation, they placed the baby back in the adult’s enclosure, together with an unknown baby. Adult rats which lacked vasopressin failed to recognise the familiar baby.

Google take-away

In the wake of Google’s spat with the Chinese government, Nature’s news team surveyed scientists in China to find out how much they rely on Google – and what the consequences would be if they lost access to the search engine.

More than three-quarters of the scientists quizzed said they use Google as the primary search engine for their research. Over 80 per cent use the search engine to find academic papers; close to 60 per cent use it to get information about scientific discoveries or other scientists’ research programmes; and more than half use the literature search Google Scholar.

Eighty four per cent of the scientists who responded to Nature’s survey said their research would be “somewhat or significantly” hampered by losing access to Google and 78 per cent said that international collaborations would be affected to the same degree.

One Chinese scientist said: “Research without Google would be like life without electricity.”

The full survey results are online at www.go.nature.com/FJ6QTm

Gas-giant losing atmosphere to star

A recently discovered extrasolar planet is losing its atmosphere to its host star, according to a paper published in Nature this week.
A team at Peking University in Beijing analysed WASP-12b, a gas-giant planet larger than Jupiter. The planet is orbiting very close to its star, and has a surprisingly large radius. Although WASP-12b is strongly heated by its host star, this energy source is not sufficient to explain the planet’s inflated size.

The team, led by Shu-lin Li, suggest that WASP-12b’s close orbit subjects it to extremely large tidal forces. These forces are spread throughout the body of the planet, providing an energy source for the planet’s large volume. The authors infer that WASP-12b’s atmosphere is escaping the planet’s gravitational field, and flowing towards the host star.

Clipping the wings of dengue and malaria

An estimated 50–100 million new dengue fever infections occur each year in tropical countries, and improved control of the mosquito species which carries the disease could save many lives.

Now a team of scientists have developed genetically modified strains of Aedes aegypti, the mosquito which carries dengue. The modified male mosquitoes carry a gene which interferes with wing growth.

Research led by Guoliang Fu of the University of Oxford, and published in the Proceedings of the National Academy of Sciences (PNAS), suggests releasing the GM male mosquitoes to mate with females. The resulting female offspring would then be born with the gene limiting wing growth.

The team estimates the new breed could sustainably suppress the native mosquito population in six to nine months.

The same technique could be used in the future to tackle mosquitoes that spread malaria.