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Neanderthal extinction refers to the sudden disappearance of Neanderthals during a time when modern humans began to emerge in Eurasia. Since the discovery of Neanderthal remains, both the Neanderthals' place in the human family tree and their relation to modern humans has been hotly debated. At different times, they have been classified as a separate species (''Homo neanderthalensis'') and as a subspecies (''Homo sapiens neanderthalensis''). In August 2014, a team reported on a new analysis of 40 sites in Western Europe, concluding that Neanderthals died out about 40,000 years ago.〔(Kenneth Chang, "Neanderthals in Europe Died Out Thousands of Years Sooner Than Some Thought, Study Says" ), ''New York Times,'' 20 August 2014, accessed 23 August 2014〕 This date, much earlier than previous estimates, was established through improved radio carbon dating methods. Researchers want to expand their survey of sites to Eastern Europe and Siberia, as Neanderthals may have survived longer there. Hypotheses on the fate of the Neanderthals include a failure or inability to adapt to climate change, competitive exclusion, or extinction by encroaching anatomically modern humans, who arrived in Europe long after Neanderthals had settled there. Neanderthal hybridization with early modern human populations is also considered a viable hypothesis. Some interbreeding took place in western Asia about 50,000 to 60,000 years ago, as evidenced by 1 to 4 percent of the material of genomes carried by non-African people living today.〔 ==Coexistence prior to extinction== The new evidence narrows the period in which both Neanderthals and modern humans coexisted in Europe to approximately 5,000 years.〔 The duration of this period is uncertain. There is evidence that modern humans reached Europe sometime between 45,000 and 43,000 years ago.〔http://www.nytimes.com/2011/11/03/science/fossil-teeth-put-humans-in-europe-earlier-than-thought.html?scp=1&sq=kents%20cavern&st=cse&_r=0〕 The new evidence, based on conclusions from improved radiocarbon dating indicates that Neanderthals became extinct 40,000 years ago, which overturns older less accurate carbon dating which incorrectly indicated that Neanderthals may have lived as recently as 24,000 years ago in refugia on the south coast of the Iberian peninsula such as Gorham's Cave. Inter-stratification of Neanderthal and modern human remains has been suggested, but is disputed. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Neanderthal extinction」の詳細全文を読む スポンサード リンク
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