PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES—Researchers report* that an absence of Neanderthal tools during Paleolithic European cold periods suggests that the cold periods influenced the decline of Neanderthals and the rise of modern humans. The transition from Neanderthal to modern human populations in Europe occurred during a period of recurring cold climate cycles, although the link between the climate cycles and the decline of Neanderthals has not been established. Michael Staubwasser and colleagues examined paleoclimate records from stalagmites in east-central Europe covering a period from 44,000 to 40,000 years ago, and compared the data to archaeological records of Neanderthal artifacts from across Europe. The authors found that archaeological layers devoid of Neanderthal tools occurred at around the same time as cold periods called stadials. Following the cold periods, Europe experienced periods of genetic turnover as modern humans expanded, and evidence suggests that the last interbreeding between modern humans and Neanderthals occurred four to six generations before the Neanderthals disappeared from the archeological record. The Neanderthals’ diet, which was more limited than that of humans, may explain their decline during cold periods. Under the ecological stress of a changing climate, the terrestrial meat sources on which the Neanderthals relied may have become scarce, whereas human diet was supplemented with plant and aquatic food sources, enabling them to survive. According to the authors, repeated population-depopulation cycles during stadials may have altered the genetic character of ancient Europe.
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Tausoare Cave in the East Carpathians, Romania. Crin Theodorescu
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Ascunsa Cave in the South Carpathians, Romania. PNAS
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Article Source: PNAS news release
*”Impact of climate change on the transition of Neanderthals to modern humans in Europe,” by Michael Staubwasser et al.
