Neanderthals, our heavy-browed relatives, spread out across Europe and Asia about 200,000 years ago. But when did they die out, giving way to modern humans?

A new analysis of Neanderthal sites from Spain to Russia provides the most definitive answer yet: about 40,000 years ago, at least in Europe.

That is thousands of years earlier than some scientists have suggested, and it narrows the period that Neanderthals and modern humans overlapped in Europe.

“After that, we don’t think there are any Neanderthals on the continent anymore,” said Thomas Higham, the deputy director of the radiocarbon accelerator unit at the University of Oxford in England.