Looking for loss in all the wrong places: loss avoidance does not explain cheater detection

The ability to detect cheaters has been proposed as an adaptive design feature of psychological adaptations for cooperation. This proposal has been tested with studies on the Wason selection task, which purportedly demonstrate that humans possess a specific competence for detecting cheaters in cooperative interactions. An alternative set of theories suggests that people are not looking for cheaters per se, but are looking for losses in an effort to maximize their utility. In previous investigations of cheater detection, cheating has been confounded with someone suffering a loss. We sought to test rival accounts of cheater detection by devising versions of the selection task in which cheating is unconfounded with losses. The results suggest that people are competent at detecting cheaters even when no losses are involved, lending support to the view that cheater detection is a specific design feature of psychological adaptations for cooperation.     

Group selection, kin selection, altruism and cooperation: When inclusive fitness is right and when it can be wrong

Group selection theory has a history of controversy. After a period of being in disrepute, models of group selection have regained some ground, but not without a renewed debate over their importance as a theoretical tool. In this paper I offer a simple framework for models of the evolution of altruism and cooperation that allows us to see how and to what extent both a classification with and one without group selection terminology are insightful ways of looking at the same models. Apart from this dualistic view, this paper contains a result that states that inclusive fitness correctly predicts the direction of selection for one class of models, represented by linear public goods games. Equally important is that this result has a flip side: there is a more general, but still very realistic class of models, including models with synergies, for which it is not possible to summarize their predictions on the basis of an evaluation of inclusive fitness.     

Memory versus spatial disorder in the support of cooperation

In the conventional spatial formulation of the iterated prisoner’s dilemma only the results generated in the last round are taken into account in deciding the next choice. Historic memory can be implemented by featuring players with a summary of their previous winnings and moves. The effect of memory as a mechanism of supporting cooperation versus spatial disorder is assessed when the players are allowed for continuous degree of cooperation, not the mere binary cooperation/defection disjunctive.     

Simple scaling of cooperation in donor-recipient games

We present a simple argument which proves a general version of the scaling phenomenon recently observed in donor-recipient games by Tanimoto [Tanimoto, J., 2009. A simple scaling of the effectiveness of supporting mutual cooperation in donor-recipient games by various reciprocity mechanisms. BioSystems 96, 29–34].