A model is presented to account for the natural selection of what is termed reciprocally altruistic behavior. The model shows how selection can operate -against the cheater (non-reciprocator) in the system. Three instances of altruistic behavior are discussed, the evolution of which the model can explain: (1) behavior involved in cleaning symbioses; (2) warning cries in birds: and (3) human reciprocal altruism. Regarding human reciprocal altruism, it is shown that the details of the psychological system that regulates this altruism can (...) be explained by the model. Specifically, friendship,d islike, moralistic aggression, gratitude, sympathy, trust, suspicion, trustworthiness, aspects of guilt, and some forms of dishonesty and hypocrisy can be explained as important adaptations to regulate the altruistic system. Each individual human is seen as possessing altruistic and cheating tendencies, the expression of which is sensitive to developmental variables that were selected to set the tendencies at a balance appropriate to the local social and ecological environment. (shrink)

Intent and mitigating circumstances play a central role in moral and legal assessments in large-scale industrialized societies. Al- though these features of moral assessment are widely assumed to be universal, to date, they have only been studied in a narrow range of societies. We show that there is substantial cross-cultural variation among eight traditional small-scale societies (ranging from hunter-gatherer to pastoralist to horticulturalist) and two Western societies (one urban, one rural) in the extent to which intent and mitigating circumstances influence (...) moral judgments. Although participants in all societies took such factors into account to some degree, they did so to very different extents, varying in both the types of considerations taken into account and the types of violations to which such considerations were applied. The particular patterns of assessment characteristic of large-scale industrialized societies may thus reflect relatively recently culturally evolved norms rather than inherent features of human moral judgment. (shrink)

The 'Evolution of Cooperation' addresses a simple yet age-old question; If living things evolve through competition, how can cooperation ever emerge? Despite the abundant evidence of cooperation all around us, there existed no purely naturalistic answer to this question until 1979, when Robert Axelrod famously ran a computer tournament featuring a standard game-theory exercise called The Prisoner's Dilemma. To everyone's surprise, the program that won the tournament, named Tit for Tat, was not only the simplest but the most "cooperative" entrant. (...) This unexpected victory proved that cooperation - one might even say altruism - is mathematically possible and therefore needs no hidden hand or divine agent to create and sustain it. A great roadblock to the understanding of all sorts of behavior was at last removed. The updated edition includes an extensive new chapter on cooperation in cancer cells and among terrorist organizations. (shrink)

A long-standing theoretical tradition in clinical psychology and psychiatry sees deliberate self-harm , such as wrist-cutting, as “functional”—a means to avoid painful emotions, for example, or to elicit attention from others. There is substantial evidence that DSH serves these functions. Yet the specific links between self-harm and such functions remain obscure. Why don’t self-harmers use less destructive behaviors to blunt painful emotions or elicit attention? Economists and biologists have used game theory to show that, under certain circumstances, self-harmful behaviors by (...) economic agents and animals serve important strategic goals. In particular, “costly signals” can credibly reveal a “private state” in situations where verbal claims and other “cheap” signals might be disbelieved. Here, DSH is scrutinized using signaling theory, and a variant, the theory of bargaining with private information. The social contexts and associated features of DSH suggest that it might be a costly, and therefore credible, signal of need that compels social partners to respond. (shrink)

Emotions are discrete, automatic responses to universally shared, culture-specific and individual-specific events. The emotion terms, such as anger, fear, etcetera, denote a family of related states sharing at least 12 characteristics, which distinguish one emotion family from another, as well as from other affective states. These affective responses are preprogrammed and involuntary, but are also shaped by life experiences.

Data on birth order and parent-offspring relations for 1,601 adolescents participating in the National Longitudinal Study of Adolescent Health were used to test hypotheses about the role of adolescent suicidal behavior in parent-offspring conflict. Among adolescents highly dissatisfied with their mothers, the odds that middleborns would make at least one suicide attempt was 23% that of first- and lastborns (p<.001), but their odds of receiving medical treatment for their attempts was 8.5 times greater than the odds for first- and lastborns (...) (p=.032). The results are tentatively interpreted as supporting the hypothesis that adolescents use suicide attempts to leverage investment from their parents. (shrink)

Cross-cultural comparisons can a) illuminate the manner in which cultures differentially highlight, ignore, and group various facets of emotional experience, and b) shed light on our evolved species-typical emotional architecture. In many societies, concern with shame is one of the principal factors regulating social behavior. Three studies conducted in Bengkulu and California explored the nature and experience of shame in two disparate cultures. Study 1, perceived term use frequency, indicated that shame is more prominent in Bengkulu, a collectivistic culture, than (...) in California, an individualistic culture. Study 2, comparing naturally occurring shame events with reports thereof, revealed that shame is associated with guilt-like accounts in California but not in Bengkulu, and subordinance events in Bengkulu but not in California; published reports suggest that the latter pattern is prominent worldwide. Study 3 mapped the semantic domain of shame using a synonym task; again, guilt was prominent in California, subordinance in Bengkulu. Because shame is overshadowed by guilt in individualistic cultures, and because these cultures downplay aversive emotions associated with subordinance, a fuller understanding of shame is best arrived at through the study of collectivistic cultures such as Bengkulu. After reviewing evolutionary theories on the origins and functions of shame, I evaluate these perspectives in light of facets of this emotion evident in Bengkulu and elsewhere. The available data are consistent with the proposition that shame evolved from a rank-related emotion and, while motivating prestige competition, cooperation, and conformity, nevertheless continues to play this role in contemporary humans. (shrink)