Recognition memory and the evolution of cooperation: How simple strategies succeed in an agent-based world

Recent approaches to understanding the cognitive mechanisms underlying decision processes suggest that simple strategies can result in successful and adaptive behaviors. Here, the evolutionary success of simple recognition memory is investigated. Agents have a limited memory capacity for either agents who have previously cooperated (C-Mem) or those that have previously defected (D-Mem). Various aspects of the ecological and social environment influence the success of each of these strategies. These findings suggest that recognition memory can play a role in promoting the evolution of cooperation, but that the effectiveness of such a simple recognition memory strategy depends on the fit between that strategy and the (ecological and social) environment in which that strategy is employed. The D-Mem strategy is able to invade only when the memory size of these agents is close to the total number of defectors in the population. However, the C-Mem strategy can invade a population of defectors when memory size is one, as long as the population size is relatively small and the ecological environment promotes longer intervals between each reproductive opportunity.