The Evolution of Cooperation in a Simulated Inter-Group Conflict

Abstract

The present study simulates an enduring intergroup conflict in which each one of two interacting groups is represented by a unitary representative elected for a given constituency period. We assume that the conflict between the two groups can be modeled as an iterated Prisoner’s Dilemma game played by the groups’ representatives. In addition, we assume that the performance of each representative influences her constituents and that this, in turn, affects her prospects to be reelected. At the end of a constituency period, new elections are called for, and their results determine whether she remains in her position or is replaced by another representative. Our main objectives are: (1) to investigate the effect of this common democratic procedure, namely, the periodic election of group representatives, on the evolution of cooperation between the groups; and (2) to investigate the effect of the frequency of elections in the two groups on the evolving intergroup relations. Results of 150 simulations yield the following main results: (1) the dynamics of the intergroup conflict evolve into phases of welldefined patterns. (2) when mutual cooperation emerged, it was more enduring for high than for low rates of cooperation between the groups’ representatives; and (3) the prospects for reaching phases of mutual cooperation along the evolutionary path were considerably better for longer election periods, than for shorter ones.