According to new data by the Max Planck Institute for Evolutionary Anthropology, Neanderthals and modern humans were interbreeding much earlier than was previously thought.
"We now find evidence for a modern human contribution to the Neanderthal genome. This is likely the result of much earlier interbreeding," study co-author Sergi Castellano says.
Various DNA analysis techniques suggest that we started mixing with our now-extinct relatives about 100,000 years ago. Researchers had previously thought that the two species first encountered each other when modern humans left Africa, about 65,000 years ago.