Great apes appear to build friendships much like humans do. By studying grooming behavior, researchers discovered that chimpanzees and bonobos form close inner circles along with wider networks of ...

Think about how you manage your friendships. There are a handful of people you trust and confide in, then there is the wider ring of acquaintances you stay in touch with, but keep at a certain ...

The 42-year-old chimpanzee lounges lazily on the branch, eyeing us congenially. Far from being bothered by our presence, he seems to be actively enjoying it, striking the sort of poses a catalogue ...