The researchers found the first example of our species (the modern man) outside of Africa.
A skull discovered in Greece was dated 210,000 years ago, at a time when Europe was occupied by Neanderthals.
This sensational discovery adds to the evidence of an earlier migration of people from Africa who left no trace in the DNA of living people today.
The results are published in the journal Nature.
The researchers discovered two important fossils in the Apidima cave in Greece in the 1970s.
One was very deformed and the other incomplete, however, and it took a CT scan and serial uranium dating to unravel their secrets.
The more complete skull seems to be a Neanderthal. But the other shows clear features, like a rounded back to the skull, a diagnosis of the modern man.
The modern man left Africa much earlier
In addition, the Neanderthal skull was younger.
"Our scenario was that 210,000 years ago there existed a modern day modern group in Greece, perhaps related to comparable populations of the Levant, but it was later replaced by a Neanderthal population (represented by Apidima 2) about 170 000 years ago, "said co-author Chris Stringer of the Natural History Museum in London.
People living outside Africa today are from a migration that left the continent 60,000 years ago.
When these modern humans spread across Eurasia, they largely replaced other species encountered, such as Neanderthals and Denisovans.
But it was not the first migration of modern man (Homo sapiens) of Africa.
Homo sapiens The fossils of Skhul and Qafzeh in Israel were dated in the 90s, 90,000 to 125,000 years ago.
These were considered anomalies – a brief incursion outside our African homeland that hardly took place.
However, in recent years we have come to understand that our species was outside of Africa well before and beyond.
In recent years, paleontologists have discovered modern human fossils dating back 80,000 to 120,000 years from Daoxian and Zhirendong in China.
DNA studies have revealed signs of early miscegenation between African and Neanderthal humans. Evidence provided by German Neanderthals shows that the mixture occurred between 219,000 and 460,000 years ago, although it is not clear whether Homo sapiens has been involved, or another early African group.
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