Human adults engage in costly third-party punishment of unfair behavior, but the developmental origins of this behavior are unknown. Here we investigate costly third-party punishment in 5- and 6-year-old children. Participants were asked to accept (enact) or reject (punish) proposed allocations of resources between a pair of absent, anonymous children. In addition, we manipulated whether subjects had to pay a cost to punish proposed allocations. Experiment 1 showed that 6-year-olds (but not 5-year-olds) punished unfair proposals more than fair proposals.
Proceedings of the National Academy of Sciences of the United States of America
The profound benefits of altruism in modern society are self-evident. However, the potential hurtful aspects of altruism have gone largely unrecognized in scientific inquiry. This is despite the fact that virtually all forms of altruism are associated with tradeoffs--some of enormous importance and sensitivity--and notwithstanding that examples of pathologies of altruism abound. Presented here are the mechanistic bases and potential ramifications of pathological altruism, that is, altruism in which attempts to promote the welfare of others instead result in unanticipated harm.
People value rewards to others but discount those rewards based on social distance; rewards to a socially closer person are valued more than identical rewards to a socially more distant person (Jones and Rachlin, 2006). The concept of social discounting can explain cooperation and defection in two-player prisoner's dilemma (PD) games (Axelrod, 1980). The contingencies of a PD game are such that in any single game cooperation is costly to each player herself but beneficial to the other player.
Contingent reciprocity is important in theories of the evolution of human cooperation, but it has been very little studied in ontogeny. We gave 2- and 3-year-old children the opportunity to either help or share with a partner after that partner either had or had not previously helped or shared with the children. Previous helping did not influence children's helping. In contrast, previous sharing by the partner led to greater sharing in 3-year-olds but not in 2-year-olds.
The study of cooperation is rich with theoretical models and laboratory experiments that have greatly advanced our knowledge of human uniqueness, but have sometimes lacked ecological validity. We therefore emphasize the need to tie discussions of human cooperation to the natural history of our species and its closest relatives, focusing on behavioral contexts best suited to reveal underlying selection pressures and evolved decision rules.
Helping, i.e. behaviour increasing the fitness of others, can evolve when directed towards kin or reciprocating partners. These predictions have been tested in the context of food sharing both in human foragers and non-human primates. Here, we performed quantitative meta-analyses on 32 independent study populations to (i) test for overall effects of reciprocity on food sharing while controlling for alternative explanations, methodological biases, publication bias and phylogeny and (ii) compare the relative effects of reciprocity, kinship and tolerated scrounging, i.e.
The widespread existence of cooperation is difficult to explain because individuals face strong incentives to exploit the cooperative tendencies of others. In the research reported here, we examined how the spread of reputational information through gossip promotes cooperation in mixed-motive settings.
Concerns for reputation can promote cooperative behaviour. Individuals that behave cooperatively stand to benefit if they gain in influence, status or are more likely to be chosen as interaction partners by others. Most theoretical and empirical models of cooperation predict that image score will increase with cooperative contributions. Individuals are therefore expected to make higher contributions when observed by others and should opt to make contributions publicly rather than privately, particularly when contributions are higher than average. Here, however, I find the opposite effect.
Humans are an intensely social species, frequently performing costly behaviors that benefit others. Efforts to solve the evolutionary puzzle of altruism have a lengthy history, and recent years have seen many important advances across a range of disciplines. Here we bring together this interdisciplinary body of research and review the main theories that have been proposed to explain human prosociality, with an emphasis on kinship, reciprocity, indirect reciprocity, punishment, and morality.
Cooperation can be maintained if individuals reciprocate favors over repeated interactions. However, it is not known when during development the psychological capacities to engage in contingent reciprocation emerge. Therefore, we tested when children begin to differentiate between reciprocal and nonreciprocal interactions in their resource sharing. We compared the sharing behavior of 3- and 5-year-olds in two situations. In an experimental condition, the child and a puppet partner alternated the roles of donor and recipient.