Humans and Neanderthals cozied up from time to time when they lived in the same areas tens of thousands of years ago. But we don't know much about who got with whom, or why. A new genetic analysis offers some ancient gossip: The pairings were more often female humans with male Neanderthals.

Neanderthal males had sex with human women, but human men were not so enamoured with Neanderthal females, new research suggests.