The effects of unequal reward distributions on cooperative problem solving by cottontop tamarins, Saguinus oedipus

Cooperation among nonhuman animals has been the topic of much theoretical and empirical research, but few studies have examined systematically the effects of various reward payoffs on cooperative behaviour. Here, we presented heterosexual pairs of cooperatively breeding cottontop tamarins with a cooperative problem-solving task. In a series of four experiments, we examined how the tamarins’ […]

Do Chimpanzees (Pan troglodytes) Spontaneously Take Turns in a Reciprocal Cooperation Task?

Reciprocity is considered to be an explanation for altruism toward nonkin. Although there have been many theoretical studies and reciprocity is arguably prevalent in humans, little experimental work has investigated the proximate mechanism of reciprocity in nonhuman animals. The authors tested whether pairs of chimpanzees (Pan troglodytes) would achieve reciprocal cooperation, that is, whether chimpanzees […]

Chimpanzee (Pan troglodytes) anticipation of food return: Coping with waiting time in an exchange task

Despite controversial expectations that animals achieve reciprocal altruism, it is unclear if nonhuman species possess the necessary cognitive abilities. For reciprocal altruism, individuals must anticipate the loss of a commodity and accept a delay before some return. The authors investigated the abilities of 5 chimpanzees (Pan troglodytes) to cope with increasing waiting duration in exchange […]

Grooming and coalitions in Japanese macaques (Macaca fuscata): Partner choice and the time frame reciprocation

Evidence of a reciprocal exchange of grooming and agonistic support in primates is mixed. In this study, the authors analyzed a large database of grooming and coalitions in captive female Japanese macaques (Macaca fuscata) to investigate their within-group distribution and temporal relations. Macaques groomed preferentially those individuals that groomed them most and supported preferentially those […]