Homo Sapiens' Sex With Extinct Species Was No One-Night Stand

WASHINGTON, March 18 (Reuters) - 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 on 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. The researchers found some of the genes inherited from these extinct species were beneficial for our species. Many are involved in the immune system and likely helped protect against pathogens, and some play important roles in skin and hair biology, said University of Washington evolutionary geneticist Joshua Akey, who helped lead the study published in the journal Science. The researchers analyzed DNA sequences from 35 people living on Northern Island Melanesia off the coast of New Guinea. These Melanesians were found to have about 2 percent Neanderthal ancestry plus an additional genetic contribution of roughly 2 to 4 percent from Denisovans. The non-African populations studied had roughly 1.5 to 4 percent Neanderthal genet...
Source: Science - The Huffington Post - Category: Science Source Type: news