Humans are an ultrasocial species. This sociality, however, cannot be fully explained by the
canonical approaches found in evolutionary biology, psychology, or economics …

The current review aims to unify existing views of altruism through an examination of the
biological bases of a fundamental form of giving: altruistic responding. Altruistic responding …

Humans are a puzzling species. On the one hand, we struggle to survive on our own in the
wild, often failing to overcome even basic challenges, like obtaining food, building shelters …

We send money to help famine victims halfway around the world. We campaign to save
whales and oceans. We stay up all night to comfort a friend with a broken relationship …

Convergent evidence from many species reveals the evolutionary origins of human
friendship. In horses, elephants, hyenas, dolphins, monkeys, and chimpanzees, some …

Animals that maintain cooperative relationships show gains in longevity and offspring
survival. However, little is known about the cognitive or hormonal mechanisms involved in …

Although cooperation is a widespread phenomenon in nature, human cooperation exceeds
that of all other species with regard to the scale and range of cooperative activities. Here we …

This article has two goals. The first is to assess, in the face of accruing reports on the
ingenuity of great ape tool use, whether and in what sense human tool use still evidences …

Humans extensively help others altruistically, which plays an important role in maintaining
cooperative societies. Although some nonhuman animals are also capable of hel** others …

A growing body of evidence shows that humans are remarkably altruistic primates. Food
sharing and division of labor play an important role in all human societies, and cooperation …