title: Did warfare among ancestral hunter-gatherers affect the evolution of human social behaviors?
abstract: Since Darwin, intergroup hostilities have figured prominently in explanations of the evolution of human social behavior. Yet whether ancestral humans were largely "peaceful" or "warlike" remains controversial. I ask a more precise question: If more cooperative groups were more likely to prevail in conflicts with other groups, was the level of intergroup violence sufficient to influence the evolution of human social behavior? Using a model of the evolutionary impact of between-group competition and a new data set that combines archaeological evidence on causes of death during the Late Pleistocene and early Holocene with ethnographic and historical reports on hunter-gatherer populations, I find that the estimated level of mortality in intergroup conflicts would have had substantial effects, allowing the proliferation of group-beneficial behaviors that were quite costly to the individual altruist.
authors.affiliation: Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA. samuel.bowles@gmail.com
authors.forename: Samuel
authors.initials: S
authors.lastname: Bowles
mesh_terms: D000533:Altruism; D000884:Anthropology, Cultural; D001106:Archaeology; D005075:Biological Evolution; D003299:Cooperative Behavior; D003468:Cultural Evolution; D005260:Female; D014644:Genetic Variation; D006801:Humans; D008297:Male; D018895:Microsatellite Repeats; D008962:Models, Theoretical; D012919:Social Behavior; D014857:Warfare