Kate Moss, George Clooney, Natalie Portman and Brad Pitt may be many people's ideas of dream dates. But pioneering research which combines economics and biology suggests they may not be perfect life partners.
According to a study to be discussed this month at a gathering of Nobel prize winners, people blessed with more symmetrical facial features, which are considered more attractive, are less likely to co-operate and more likely to selfishly focus on their own interests.
Santiago Sanchez-Pages who works at the universities of Barcelona and Edinburgh and Enrique Turiegano of the Universidad Autonoma de Madrid base their claims on the "prisoner's dilemma" model of behaviour, played out under laboratory conditions.
Two players were given the option of being a "dove" and co-operating for the greater good; or a "hawk" and taking the selfish option, with a chance of gaining more if the other player chooses "dove" and co-operates. The subjects' faces were then analysed.
The study found that people with more symmetrical faces were less likely to co-operate and less likely to expect others to co-operate.