Olson and Spelke ran three related studies in which the children were introduced to a “protagonist” doll which, at certain times, benefited from pro-social behavior from other dolls. The children were then given the opportunity to direct the protagonist doll either to share or not share a resource (for example, stickers, pennies) with other dolls.The results: the kids showed an innate predisposition to indirect reciprocity - "I help you, someone else helps me". This is a key feature of human society, since it allows the formation of co-operative groups large enough for individuals to be unknown to others that they might come across. It's key to the development of towns, for example. This new study shows that it is a product of our evolution. Olson and Spelke write:
Observations and experiments show that human adults preferentially share resources with close relations, with people who have shared with them (reciprocity), and with people who have shared with others (indirect reciprocity). These tendencies are consistent with evolutionary theory but could also reflect the shaping effects of experience or instruction in complex, cooperative, and competitive societies. Here, we report evidence for these three tendencies in 3.5-year-old children, despite their limited experience with complex cooperative networks. Three pillars of mature cooperative behavior therefore appear to have roots extending deep into human development.Indirect reciprocity works from an evolutionary perspective because it allows individuals to enhance their reputation - and those individuals with a high reputation are more likely to gain the trust and co-operation of others. The mathematician Karl Sigmund discusses his perspective on indirect reciprocity in an essay hosted on The Edge.
K OLSON, E SPELKE (2008). Foundations of cooperation in young children Cognition, 108 (1), 222-231 DOI: 10.1016/j.cognition.2007.12.003