It’s no surprise that children are shaped by their societies. A new study published this afternoon in the Proceedings of the National Academy of Sciences found that a child’s tendency toward cooperation can be shaped by local social norms, but children did not act on these tendencies until early elementary age.
What sets this study, on the “Ontogeny of Prosocial Behavior Across Diverse Societies,” apart from others of its kind is its wide sampling of societies. Researchers led by Bailey House, an anthropologist at the University of California, Los Angeles, found children from widely disparate walks of life—from city kids to farmers, herders, and foragers—similarly cooperate in tasks that require no sacrifice and become progressively more selfish through early childhood, before aligning with their community norms around age 7 to 8.
“We know that kids are sensitive to culture early on,” House said. This trajectory that the tests revealed, though, was somewhat unexpected. “We assumed we would start to see the differences emerge very early, but this work starts to draw a little bit of a distinction about when those differences start to emerge. It helps focus on an age range.”
Researchers tested the cooperation of 326 children, between the ages of three and 14, and 120 adults, all from six varied world societies. They included: nomadic hunter-gatherers living in the Congo Basin, slash and burn horticulturalists from Amazonia, sedentized foragers from Australia, marine forager-horticulturalists from Melanesia, and urban Americans in Los Angeles.
Two games measured participants’ tendencies toward cooperation. In one, participants could share at zero costs to themselves. In the other, sharing had personal costs.
Rather than their behaviors shifting at a steady increment to resemble those of their societies’ adults, children across all societies behaved relatively the same until about age seven or eight (middle childhood): when sharing had personal costs, the children became increasingly selfish. Starting at middle childhood, though, their behaviors increasingly began to reflect those of the adults in their society.
From here, explained House, researchers can go back and see what it is that’s going on in middle childhood that causes them to begin to comply with their social norms at that specific age.