Sex and contextual effects on children's use of interference competition

Prior research with children and nonhuman animals suggests that females engage in interference competition, in which I individual reduces another's chances of gaining access to a resource, only when resources are scarce, whereas males use it more widely. This study was designed to compare males' and females' use of interference competition in games in which resources were scarce or plentiful. Forty groups of 4 same-sex children from kindergarten or Grade 4 played the 2 games on 2 days. Grade 4 girls used less interference competition when resources were plentiful than when they were scarce. Results are useful for generating a contextually based model of the development of sex differences in competitive behavior.