title: The co-evolution of individual behaviors and social institutions.
abstract: We present agent-based simulations of a model of a deme-structured population in which group differences in social institutions are culturally transmitted and individual behaviors are genetically transmitted. We use a standard extended fitness accounting framework to identify the parameter space for which this co-evolutionary process generates high levels of group-beneficial behaviors. We show that intergroup conflicts may explain the evolutionary success of both: (a) altruistic forms of human sociality towards unrelated members of one's group; and (b) group-level institutional structures such as food sharing which have emerged and diffused repeatedly in a wide variety of ecologies during the course of human history. Group-beneficial behaviors may evolve if (a) they inflict sufficient fitness costs on outgroup individuals and (b) group-level institutions limit the individual fitness costs of these behaviors and thereby attenuate within-group selection against these behaviors. Thus, the evolutionary success of individually costly but group-beneficial behaviors in the relevant environments during the first 90,000 years of anatomically modern human existence may have been a consequence of distinctive human capacities in social institution building.
authors.affiliation: Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA. bowles@santafe.edu
authors.forename: Samuel
authors.initials: S
authors.lastname: Bowles
authors.forename: Jung-Kyoo
authors.initials: JK
authors.lastname: Choi
authors.forename: Astrid
authors.initials: A
authors.lastname: Hopfensitz
mesh_terms: D000533:Altruism; D005075:Biological Evolution; D003299:Cooperative Behavior; D006126:Group Processes; D006801:Humans; D008960:Models, Psychological; D012931:Social Environment