A fresh look at fossilized remains has turned up a surprise: the earliest modern people in Europe.
From stone tools and other artifacts, scientists have long suspected that the earliest populations of Homo sapiens, or modern humans, settled the continent between 42,000 and 44,000 years ago.
But there were no human fossils dating back to that time. The evidence put the earliest modern European at no older than 40,000 years old.
Two new studies published online Wednesday in the journal Nature fill in the gap. Two teams of researchers took another look at previously excavated remains in Italy and England and determined that they dated back to an earlier period.
The studies "push back the time when we can absolutely say" modern people occupied Europe, New York University anthropologist Shara Bailey, who had no connection with the research, said in an email.
In both cases, modern dating techniques were used to get more accurate ages.
A group led by Stefano Benazzi of the University of Vienna studied two tiny teeth recovered from an ancient cave in southern Italy in 1964. The molars were originally thought to belong to a Neanderthal infant. Researchers compared the teeth to those from a modern human and Neanderthal, and concluded the teeth were wrongly categorized.
To determine the age, researchers did radiocarbon dating of shell bead ornaments from the same Italian site because the teeth were too small to directly analyze. This method suggested the teeth were between 43,000 and 45,000 years old, making them the oldest known modern human remains in Europe.
Benazzi said the new age means ornaments and bone tools found at the site and attributed to Neanderthals were instead produced by modern humans.
A separate team led by Thomas Higham of Oxford University re-examined a piece of jawbone unearthed from a prehistoric cave in England in 1927. The specimen was thought to be 35,000 years old, but more refined dating of the sediment layers and artifacts put it at between 41,500 and 44,200 years old _ in the same general age range as the teeth.
The studies complement each other and "provide solid dates on scrappy but well-identified fossils indicating that modern humans were present" in southern and northwestern Europe during this time, Eric Delson, an anthropologist at Lehman College of the City University of New York, said in an email.
This earlier time frame means modern humans in Europe co-existed for several thousand years with Neanderthals, stocky hunters that became extinct around 30,000 years ago. The studies do not address whether the two species socialized, but recent genome work found interbreeding between Neanderthals and modern humans in the Middle East.
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