How did cooperative behavior prevail in human evolution? NOMIS Board Member Ernst Fehr, together with other researchers from the Universities of Zurich, Lausanne and Konstanz, have challenged two prevailing explanations – repeated interactions on the one hand or group competition on the other. Instead, both mechanisms synergistically contribute to fostering cooperation effectively. Their findings were published in Nature.
One of the great unresolved mysteries of human evolution is how pro-social, cooperative behavior could have evolved. What led to the establishment of a behavior that prioritizes the benefit of the community over that of the individual in a world where materially successful individuals reproduce, and others slowly perish?
The prevailing theory suggests that this occurred due to repeated interactions. Over generations, humans learned that cooperative behavior pays off in the long run. People collaborate because they anticipate interacting with the same individuals in the future. Therefore, those who behave antisocially suffer reputational damage and are punished by others with uncooperative behavior, manifesting that uncooperative behavior does not pay off in the long run.
Exchange experiment in Papua New Guinea
However, there is strong empirical evidence that people behave cooperatively even in non-recurrent and anonymous interactions where there is no risk of reputational damage. How can this be explained? Behavioral economists from the Universities of Zurich, Lausanne and Konstanz addressed this question by conducting an experiment among indigenous people in Papua New Guinea.
In a setup resembling a trust game, pairs of individuals had to exchange money with each other and to decide whether they wanted to act selfishly and uncooperatively or rather socially and cooperatively (see box). The conclusion: when paired with an anonymous member of their own community, participants exchanged very large amounts. In pairings with members of other communities, however, very little was transferred.
Continue reading this University of Zurich story: Combination of group competition and repeated interactions promotes cooperation
Read the Nature publication: Super-additive cooperation
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