Explaining cooperation is one of the greatest problems for evolutionary biology. Cooperation often involves shared resources, and can therefore be tainted by conflicts of interest. Why should an individual carry out a costly cooperative behavior that benefits other individuals? Doing so seems to go completely against the Darwinian idea of "survival of the fittest." Cooperation is a particularly notable puzzle in species such as humans, where there is frequent cooperation between non-relatives.
A commonly suggested solution to the problem of cooperation between non-relatives is that such individuals will interact repeatedly. This allows reciprocal cooperation to evolve: individuals cooperate because it will lead to others cooperating with them in the future. Another way of looking at reciprocal cooperation is that participation avoids any punishment that would be handed out to non-collaborators.
The impact of repeated interactions has been examined in the past by observing humans asked to play the Prisoner's Dilemma game. The dilemma in this game is that not cooperating (that is, cheating) is the best short-term option, but cooperation by both players gives greater rewards than cheating by both players. It is well known that cooperation can be favored in this game if players have repeated interactions such a scenario sets up
Contact: Heidi Hardman