'Socially enforced nepotism' encourages us to help far-flung kin

So, why do people assist distant relatives? Mathematical simulations by a University of Utah anthropologist suggest "socially enforced nepotism" encourages helping far-flung kin.

The classic theory of kin selection holds that "you shouldn't be terribly nice to distant kin because there isn't much genetic payoff," says author Doug Jones. "Yet what anthropologists have observed over and over is that a lot of people are pretty altruistic toward distant kin."

Socially enforced nepotism "depends on the moral regulation of behavior according to socially transmitted norms," he writes in the study.

The findings suggest that "a lot of why you help your kin, including distant kin, isn't necessarily because you like them so much but because it's your duty, your responsibility, and other people care whether you do it," he says.

Basic kin-selection theory lacks social norms, so "you as an individual decide on your own how much to help somebody just because of how much you like them or don't like them," Jones says. "But with socially enforced nepotism, you help somebody even more because of the social pressures to do it and social rewards for helping. It improves your reputation, and improved reputation gets you more help from other people."

He says socially enforced nepotism "may help explain the phenomenon of generalized reciprocity, where members of small-scale, kin-based societies share food and other goods because they're supposed to, without expecting an exact return from the recipients."

This expanded theory of kin selection reflects the fact that "we are a very special species because of how good we are at making social rules and enforcing them," he adds. "This means relations among kin work differently in humans than in other species."

The study appears online in journal PLOS ONE.