In the sweltering heart of Senegal, in a place called Fongoli, a chimpanzee performs an earth-shattering act. She strips a branch of its leaves, chews the tip into a point and jams the tool into a hole in a tree, killing a bushbaby. In short, she has been making tools and using them to hunt. Only humans are supposed to be capable of that. Anthropologist Jill Pruetz takes us dee...