Bonobos, like humans, cooperate with unrelated members of other groups

That behavior could help shed light on the evolution of cooperation between groups of people

A female bonobo grooms a male from another group

An adult female in the Congo’s Kokolopori Bonobo Reserve grooms an adolescent male from a neighboring group of unrelated bonobos.

M. Surbeck/Kokolopori Bonobo Research Project

Humans regularly cooperate and share resources with other, unrelated humans in different social groups, often without any immediate, reciprocated benefits. The phenomenon has been considered unique to our species. But some bonobos appear to share this social trait, a study finds.