title: Evolution of cooperation by generalized reciprocity.
abstract: The evolution of cooperation by direct reciprocity requires that individuals recognize their present partner and remember the outcome of their last encounter with that specific partner. Direct reciprocity thus requires advanced cognitive abilities. Here, we demonstrate that if individuals repeatedly interact within small groups with different partners in a two person Prisoner's Dilemma, cooperation can emerge and also be maintained in the absence of such cognitive capabilities. It is sufficient for an individual to base their decision of whether or not to cooperate on the outcome of their last encounter--even if it was with a different partner.
authors: Behavioural Ecology, University of Berne, Hinterkappelen, Switzerland. thomas.pfeiffer@inf.ethz.ch
authors: Thomas
authors: T
authors: Pfeiffer
authors: Claudia
authors: C
authors: Rutte
authors: Timothy
authors: T
authors: Killingback
authors: Michael
authors: M
authors: Taborsky
authors: Sebastian
authors: S
authors: Bonhoeffer
mesh_terms: D000533:Altruism; D005075:Biological Evolution; D003071:Cognition; D003198:Computer Simulation; D003299:Cooperative Behavior; D005716:Game Theory; D006801:Humans; D008390:Markov Chains; D008962:Models, Theoretical