Prosociality and acts of altruism are defined as behaviours which benefit another with either
no gain or some immediate cost to the self. To understand the evolutionary origins of these …

How can the stunning diversity of social systems and behaviours seen in nature be
explained? Drawing on social evolution theory, experimental evidence and studies …

Patterns of primate socioecology have been used to suggest that the first truly savanna-
dwelling hominin, Homo ergaster, lived in sizeable groups. Here, we revisit these estimates …

Human cooperation may be fundamentally different from that seen in other animals. While
there are impressive examples of cooperation in other species, large-scale cooperation with …

Highlights•Pinyon jays spontaneously shared food with others.•Subjects varied in sharing
frequency and in distribution of shares.•We tested whether dominance or reciprocity …

Chimpanzees (Pan troglodytes) have been frequently observed to share food with one
another, with numerous hypotheses proposed to explain why. These often focus on …

A variety of studies on food sharing elucidate both its ultimate and proximate functions in
non-human primates, especially in Pan. For chimpanzees, food sharing serves as a means …

While food sharing among related individuals can be explained by kin selection, food
sharing between unrelated individuals has been more of an evolutionary puzzle. The food …

Humans are not alone in the animal kingdom in showing moral behavior. The precursors to
moral behavior exist in rudimentary form in many species, including our closest phylogenetic …

Wild chimpanzees routinely share high-value resources such as meat obtained through
hunting and fruit procured from raiding crops. Although it is predicted that the proximate …