Two studies published in the scientific journal Nature on Wednesday have shed new light on early human forays into Europe, suggesting that the first anatomically modern humans are a few thousand years older than previously thought.
A new analysis of two infant teeth that were excavated from a southern Italian site, Grotta del Cavallo, in the 1960s and attributed to Neanderthals now suggests they are actually from an anatomically modern human.
Stefano Benazzi, a professor of paleontology at the University of Vienna, and the lead author on the paper, reported that the teeth are between 43,000 to 45,000 years old. That makes these teeth the oldest remains of a modern human to be identified in Europe.
New results with ultrafiltration
Bildunterschrift: Großansicht des Bildes mit der Bildunterschrift: The technique involved re-examining previous samples
Scientists has also determined that a jawbone and teeth discovered in 1927 in a South England cave, Kent's Cavern, are modern human remains dating back more than 41,000 years ago.
In the 1980s, scientists deemed the remains to be about 35,000 years old, but thanks to a special carbon-dating technique called ultrafiltration, Stringer says they have now determined the remains to be some 6,000 years older.
"Modern humans got a a lot further, faster than we thought," he told the website Science Now.
Scientists raised some concerns though, about the number of tooth samples from the Italian site.
"I would say, though, that because only two teeth were found at the Grotta del Cavallo, this study is the weaker of the two," said Michael Bolus, a professor of archeology at the University of Tübingen, an interview with Deutsche Welle.
"This is because there are broad similarities between the teeth of modern humans and Neanderthals, and so the Kent's Cavern fossil, which contains several teeth, offers a more accurate picture," he said.
Overlap period extended
Bildunterschrift: Großansicht des Bildes mit der Bildunterschrift: The new studies call into question the level of interaction between Neanderthals and modern humansThe major implications of the new studies concern the period of time that Neanderthals and anatomically modern humans are believed to have overlapped, and whether Neanderthals developed to the level of sophistication that has been attributed to them through excavated tools and jewelry.
Before the new studies were published, the oldest fossils of modern humans were dated to about 40,000 years ago, with a wide margin of error accompanying this figure.
Neanderthals are believed to have disappeared 30,000 years ago. If, as the new studies suggest, Neanderthals and modern humans overlapped for thousands of years more than previously thought, they could have been more intertwined with each other.
"In the past we said that Neanderthals and anatomically modern humans didn't mix with each other, but we do know that gene material from Neanderthals can be found in modern humans," Bolus said.
"And now that this study suggests modern humans and Neanderthals overlapped for a longer period of time," he added. "The question becomes whether things like art and jewelry that have been attributed to Neanderthals were in fact from modern humans or if they were from Neanderthals following interaction with modern humans."
Re-analysis for new insights
In his report, Benazzi wrote that his team's findings show that it is "much less likely that Neanderthals developed their own Upper Paleolithic suit of behaviors before the arrival of anatomically modern humans."
Using the ultrafiltrations method employed in the new analysis of the Kent's Cavern fossil to re-examine other fossils, suggests Bolus, could provide more insight into which cultures were formed by Neanderthals and which were created by modern humans.
Author: Laura Schweiger
Editor: Cyrus Farivar
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