An ancient skull unearthed in Israel suggests a probable location where modern human began to interbreed with our Neanderthal cousins while spreading from Africa to Europe, researchers say.
The 55,000-year-old partial skull represents the first evidence of modern humans, Homo sapiens, in the Middle East at that time and contains evidence suggesting Neanderthals and modern humans mated in the region that long ago, they say.
The area is believed to be the main migratory corridor for anatomically modern humans expanding out of Africa and then into and across Eurasia, eventually replacing other forms of early human-related species including Neanderthals.
The fossil skull from the Manot Cave in northern Israel shows physical traits already somewhat different from humans staying behind in Africa, reports an international group of researchers headed by Israel Hershkovitz of Tel Aviv University.
The skull, although distinctly modern in its anatomy, resembles those of later European Cro-Magnons, another form of early modern humans, but retains some African features too, says Hershkovitz.
"Manot is the first and only modern human securely dated to 50,000 to 60,000 years ago outside the African continent. It's amazing," he says. "This is the first specimen we have that connects Africa to Europe."
The region would have already been well populated with Neanderthals when the first modern humans arrived, as proven by numbers of Neanderthals skeleton previously discovered in the local area, the researchers point out.
The Manot Cave shows signs of having been lived in over a long span of time, they say.
"Manot is the best candidate for the interbreeding of modern humans with Neanderthals and there is really no other candidate," Hershkovitz says. "The people at Manot Cave are the only population we know of that shared the same geographical region for a very long period of time."
The Manot finding represents a challenge to the previous hypothesis that Neanderthals and modern humans first encountered each other 45,000 years ago somewhere in Europe.
The Manot cave is located in a region where Neanderthals are known to have lived, perhaps driven to the warmer locale when ice sheets descended over much of Europe.
"It has been suspected that modern man and Neanderthals were in the same place at the same time, but we didn't have the physical evidence," says paleontologist Bruce Latimer of Case Western Reserve University. "Now we do have it in the new skull fossil."
"Modern humans and Neanderthals likely encountered each other foraging for food," he says.