In this edition of Perspective, we discuss a recent discovery that challenges long-held beliefs about human evolution. Researchers in France have uncovered a child's tooth and stone tools dating back some 54,000 years. The find, in a cave in the Rhône valley, suggests that modern humans arrived in Europe from Africa about 10,000 years earlier than previously thought. It also appears to indicate that they didn't immediately wipe out Neanderthals and that the two species may have co-existed for some time. For more, we speak to Professor Chris Stringer, anthropologist at the Natural History Museum in London and co-director of the Pathways to Ancient Britain project.