Nice is sexy: altruism makes men more attractive

One of the remarkable things about humans is that they sometimes are nice to each other even when they don’t expect any reward. And it’s not just humans – marmosets are altruistic too. Figuring out why behaviour like this should evolve is a challenge.

There’s a paper out by Tim Phillips, a newly minted PhD at the University of Nottingham. In it, he describes three studies that involved quizzing over 1000 men and women about what qualities they looked for in a sexual partner.

Participants in the studies were questioned about a range of qualities they look for in a mate, including examples of altruistic behaviour such as ‘donates blood regularly’ and ‘volunteered to help out in a local hospital’. Women placed significantly greater importance on altruistic traits in all three studies.

Yet both sexes may consider altruistic traits when choosing a partner. One hundred and seventy couples were asked to rate how much they preferred altruistic traits in a mate and report their own level of altruistic behaviour. The strength of preference in one partner was found to correlate with the extent of altruistic behaviour typically displayed in the other, suggesting that altruistic traits may well be a factor both men and women take into account when choosing a partner.

Dr Phillips said: “For many years the standard explanation for altruistic behaviour towards non-relatives has been based on reciprocity and reputation — a version of ‘you scratch my back and I’ll scratch yours’. I believe we need to look elsewhere to understand the roots of human altruism. The expansion of the human brain would have greatly increased the cost of raising children so it would have been important for our ancestors to choose mates both willing and able to be good, long-term parents. Displays of altruism could well have provided accurate clues to this and genes linked to altruism would have been favoured as a result.” (Press release)

Now, this stands in stark contrast to research being done over the water by a PhD student at the University of New Mexico, Peter Jonason. He’s found that male college students who exhibit the ‘dark triad’ of behaviour – the self obsession of narcissim, the callousness of psychopaths, and the deceitfullness of Machiavellianism – tended to have more partners (see New Scientist: Bad is good as a mating strategy). Once again it’s not just humans that act like this – Peter Marler showed back in the 1980s that roosters will lie to chickens – pretending they have a tasty grub when in fact they have nothing – in an effort to improve their sexual odds.

So humans show two kinds of reproductive strategies. There are people who selectively choose mates that show altruistic behaviour, since these kinds of individuals will be most likely to provide the long term investment needed for human reproduction. And then there’s the deceptive strategy.

The essential conclusions will surprise no-one, of course. But the devil is in the detail, and the implications are important for who we are. And we are who we are (sometimes nice, sometimes bad) because it’s a successful reproductive strategy.

Ref:

Phillips T, Barnard C, Ferguson E, Reader T. British Journal of Psychology, Volume 99, Number 4, November 2008 , pp. 555-572(18)