title: The evolution of reciprocity in sizable groups.
abstract: Recently, several authors have investigated the evolution of reciprocal altruism using the repeated prisoner's dilemma game. These models suggest that natural selection is likely to favor behavioral strategies leading to reciprocal cooperation when pairs of individuals interact repeatedly in potentially cooperative situations. Using the repeated n-person prisoner's dilemma game, we consider whether reciprocal altruism is also likely to evolve when social interactions involve more individuals. We show that the conditions that allow the evolution of reciprocal cooperation become extremely restrictive as group size increases.
authors.affiliation: Department of Anthropology, University of California, Los Angeles 90024.
authors.forename: R
authors.initials: R
authors.lastname: Boyd
authors.forename: P J
authors.initials: PJ
authors.lastname: Richerson
mesh_terms: D000533:Altruism; D005075:Biological Evolution; D003299:Cooperative Behavior; D006126:Group Processes; D006801:Humans; D008960:Models, Psychological