The exact time period when the modern human species (Homo sapiens) replaced the hominid
Neanderthal species (Homo
neanderthalensis) has been under significant scrutiny for quite some time.
Recently however, researchers have found that the Neanderthal extinction was
not a rapid one, and did not happen all at once. In fact, for a period of 2600-5400
years, Neanderthals and modern humans may have lived side by side. In fact,
other studies suggest that there existed some interbreeding between the two
groups, as 1.5-2.1% of modern non-African DNA originates from Neanderthals.
Professor Thomas Higham of the University of Oxford led the research by obtaining new radiocarbon dates for samples of bone, charcoal, and shell from 40 European archaeological sites believed to have been linked with the Neanderthal tool making industry (Mousterian) or transitional sites where tools belonged either to Neanderthals or early humans. Higham and his team of researchers used 14C accelerator mass spectrometry techniques to construct chronologies of these archaeological sites. Prior to Higham’s work, research regarding the coexistence of Homo sapiens and Neanderthal populations on Earth was incorrect be several millennia due to the difficulty of contaminated samples. These contaminated samples would contain 14C that was far younger than the sample itself. Because of this, the mass spectrometry results would give information that was not at all accurate. Higham was able to produce far more accurate results by using previously established archaeological statistical methods to confirm the accuracy of his carbon samples. When the carbon samples he used appeared to be contaminated with younger carbon, he would discard those samples and instead used samples that were statistically likely to show older carbon.
Professor Thomas Higham of the University of Oxford led the research by obtaining new radiocarbon dates for samples of bone, charcoal, and shell from 40 European archaeological sites believed to have been linked with the Neanderthal tool making industry (Mousterian) or transitional sites where tools belonged either to Neanderthals or early humans. Higham and his team of researchers used 14C accelerator mass spectrometry techniques to construct chronologies of these archaeological sites. Prior to Higham’s work, research regarding the coexistence of Homo sapiens and Neanderthal populations on Earth was incorrect be several millennia due to the difficulty of contaminated samples. These contaminated samples would contain 14C that was far younger than the sample itself. Because of this, the mass spectrometry results would give information that was not at all accurate. Higham was able to produce far more accurate results by using previously established archaeological statistical methods to confirm the accuracy of his carbon samples. When the carbon samples he used appeared to be contaminated with younger carbon, he would discard those samples and instead used samples that were statistically likely to show older carbon.
The data Higham collected
confirmed prior hypothesis, which estimated the end of the Mousterian time
period throughout most of Europe around the same time. The data also confirmed
that the extinction of Neanderthals in the Iberian Peninsula was far later than
anywhere else. However, the data was unable to confirm exactly how much later
Neanderthals went extinct in the Iberian Peninsula as compared to the rest of
Europe. Higham also found a connection between the appearance of modern humans
to the great innovation Neanderthals experienced during the end of the
Mousterian time period and shortly before the extinction of the population. Higham
believes that this overlap may have led to some interaction that was
responsible for such innovation, but remarks that it is not possible to confirm
this at this time.
Therefore, Higham was
able to definitively establish a time period in which both populations of Neanderthals
and populations of modern humans existed. He was also able to confirm prior
hypotheses regarding the extinction of Neanderthal populations. Further
research may prove some of his other assertions, which at this time are merely
speculation.
Citation: Higham, et.
al. 2014. The timing and spatiotemporal patterning
of Neanderthal disappearance. Nature 512,
306–309
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