Our species, Homo sapiens, has a more adventurous sexual history than previously realized, and all that bed-hopping long ago has left an indelible mark on the human genome.
Scientists said Friday an analysis of genetic information on about 1,500 people from locations around the world indicated at least four interbreeding episodes tens of thousands of years ago, three with our close cousins the Neanderthals and one with the mysterious extinct human species known as Denisovans.
People living on the remote equatorial islands of Melanesia represented the only population found to possess an appreciable level of Denisovan genetic ancestry. These Melanesians, like most human populations, also had Neanderthal genetic ancestry.