| Social norms are a central concept in human social influence and cultural processes. However, little work has been done on social norms using an evolutionary perspective. Social norms are a group property that are likely to have effects on within- and among-group behavior. I review the social influence and evolutionary literature to develop a theoretical framework of social norms from an evolutionary perspective. This framework suggests that social norms may be the result of social control mechanisms that use punishment to regulate the behaviors of group members. I report two empirical studies that examined hypotheses relevant to this framework and I present the results of an agent-based computer model that examined the evolution of altruism. The first empirical study examined whether humans have better recall of specific social information if that information is presented as being normative. This is predicted as an evolved response to the human social environment being punitively normative during human evolution. I tested this hypothesis by conducting two experiments in which participants read a text (5,250 words) describing an unfamiliar culture and were then tested on their recall of details from the account of individuals' behaviors. The data supported the hypothesis, suggesting that individuals have better recall of normative social information. The second empirical study examined the willingness of individuals to altruistically punish violators of a social norm in relation to relatedness and future interactions. I show that altruistically punishing, unlike altruistic helping, is insensitive to genetic relatedness and probability of future interactions. Finally, I model the evolution of altruism in a population with large groups (average size is 50 individuals) if groups can fission. The agent-based model incorporated several conservative biases that could be expected to operate against the evolution of altruism by group selection, including high migration rates, low mutation rate, large groups, no learning, a crude form of punishment and strong altruism. I also show that the evolution of altruistic punishment is not straightforward if punishing incurs and imposes absolute fitness decrements. |
