Altruism is behaviorally defined as an act that benefits others at the expense of the actor. Altruism is usually associated with helping others in need, but it can also take place in the context of punishment. People who help to maintain cooperation by punishing cheaters are benefiting others at their own expense as surely as if they performed acts of overt helping. The proximate psychological ...

The sanctioning of norm-transgressors is a necessary--though often costly--task for maintaining a well-functioning society. Prior to effective and reliable secular institutions for punishment, large-scale societies depended on individuals engaging in 'altruistic punishment'--bearing the costs of punishment individually, for the benefit of society. Evolutionary approaches to religion suggest tha...

Evolutionary theory predicts humans to be more altruistic towards genetically more closely related kin. Because fathers face uncertainty about the relation to their children, the asymmetric parental altruism hypothesis predicts mothers to provide a higher share of parental care than fathers. We tested this hypothesis using parental choice experiments in rural Tanzania, in which fathers and moth...

Two quasi-experiments investigated the relation between specific adult female facial features and the attraction, attribution, and altruistic responses of adult males. Precise measurements were obtained of the relative size of 24 facial features in an international sample of photographs of 50 females. Male subjects provided ratings of the attractiveness of each of the females. Positively correl...

We study delegating a consumer’s treatment plan decisions to an altruistic physician. The physician’s degree of altruism is his private information. The consumer’s illness severity will be learned by the physician, and also will become his private information. Treatments are discrete choices, and can be combined to form treatment plans. We distinguish between two commitment regimes. In the …rst...