The evolution of cooperation among non-relatives is frequently explained by direct and indirect reciprocity. Animals should base the decision to help others on expected future help, which they may judge from past behavior of their partner. Direct and indirect reciprocity thus require that individuals recognize their partner and remember what this partner did in the past. This in turn demands special cognitive abilities. I will present results from experiments that show that cooperative behavior of rats is influenced by prior receipt of help, irrespective of the identity of the partner. Results from a game theory approach further demonstrate, that if individuals repeatedly interact within small groups, cooperation can emerge and be maintained if individuals (i) base the decision whether to cooperate on the outcome of their last encounter – even if it was with a different partner, or (ii) copy the behaviour they observed in the last interaction between two anonymous partners. Based on these findings I propose two alternative mechanisms, “generalized reciprocity” and “generalized indirect reciprocity” requiring no specific knowledge about the partner, which may promote the evolution of cooperation among non-relatives. A theoretical framework for reciprocal altruism that is based on the use of different types of information - specific/unspecific, personal/public - may guide future research on the evolution of cooperation. The use of public information (such as copying observed behaviour) is of special interest as it possibly leads to cultural transmission of cooperation.
Claudia Rutte studied Biology in Germany and conducted her MSc in 1998 within the Taï Monkey Project of the Max-Planck Institute for Behavioural Physiology. In 1999 she was based at the KLIVV in Vienna and conducted a field study on Kiwi ecology in New Zealand. For her PhD (2004) she went to the University of Berne, Switzerland. Currently she is undertaking postdoctoral work in the Experimental Psychology Department at University of Cambridge. Her main research interest is the evolution of social behaviour and cognition and also how this knowledge can be applied to real world problems such as nature conservation.