Neanderthals were once widespread across Europe and western Asia. They also penetrated into the Altai Mountains of southern Siberia, but the geographical origin of these populations and the timing of their dispersal remain elusive. Archaeologists excavating Chagyrskaya Cave in the Altai foothills have found 90,000 stone artifacts, numerous bone tools, 74 Neanderthal fossils, and animal and plant remains in 59,000- to 49,000-year-old deposits. The Chagyrskaya Neanderthals made distinctive stone tools that bear a striking similarity to Neanderthal artifacts from eastern Europe, whereas other Altai sites occupied by earlier Neanderthal populations lack such artifacts. This suggests at least two dispersals of Neanderthals into southern Siberia, with the likely ancestral homeland of the Chagyrskaya toolmakers located 3,000 to 4,000 km (1,900-2,500 miles) to the west.
Reconstruction of a Neanderthal. Image credit: Neanderthal Museum.
“The most surprising discovery was how closely the Chagyrskaya stone tools resemble Micoquian tools from archaeological sites in central and eastern Europe,” said Dr. Kseniya Kolobova, a researcher in the Institute of Archaeology and Ethnography in Novosibirsk, Siberia.
Using a variety of statistical tests, Dr. Kolobova and her colleagues from Australia, Ukraine, Poland, Germany and Canada compared the distinctive stone tools found at Chagyrskaya Cave with those recovered from Micoquian sites in Europe and central Asia.
They identified the region between the Crimea and the northern Caucasus as the likely ancestral homeland of the Chagyrskaya toolmakers.
Stone artifacts from Chagyrskaya Cave: (A-C) photographs, line drawings, and cross-sectional profiles of three plano-convex bifacial tools diagnostic of Micoquian types. Scale bar – 5 cm. Image credit: Kolobova et al, doi: 10.1073/pnas.1918047117.
“This part of eastern Europe is 3,000 to 4,000 km from Chagyrskaya Cave, the equivalent of walking from Sydney to Perth or from New York to Los Angeles — a truly epic journey,” said Professor Richard ‘Bert’ Roberts, a geochronologist in the Centre for Archaeological Science at the University of Wollongong.
The analyses of animal and plant remains extracted from the Chagyrskaya Cave deposits showed that the Neanderthals were skilled at hunting bison and horses in the cold, dry and treeless environment, while microscopic study of the sediments yielded additional clues about the living conditions they had to endure.
“Neanderthals were supremely adapted to life on steppe and tundra-steppe landscapes, and could have reached the Altai Mountains from eastern Europe by going around the Caspian Sea and then east along the steppe belt,” said Dr. Maciej Krajcarz, a geoarchaeologist in the Institute of Geological Sciences in the Polish Academy of Sciences.
Early and later Neanderthal dispersals to southern Siberia. Image credit: Kseniya Kolobova / Maciej Krajcarz / Victor Chabai.
The new archaeological evidence indicates at least two separate migrations of Neanderthals into southern Siberia, and is independently supported by whole-genome studies of ancient DNA obtained from Neanderthal fossils.
The first migration occurred more than 100,000 years ago, blazing a trail to the nearby site of Denisova Cave — famous as the home of the enigmatic Denisovans, a sister group to Neanderthals, who also occupied the cave at times.
A more recent migration event — originating in eastern Europe possibly about 60,000 years ago — led to the arrival of Neanderthals at Chagysrkaya Cave, armed with their distinctive Micoquian toolkit.
DNA studies confirm a link between Neanderthals living in Europe and at Chagyrskaya Cave after 100,000 years ago.
Despite the geographic proximity of Chagyrskaya and Denisova Caves, the Chagyrskaya Neanderthal genome is more similar to those of European Neanderthals than it is to the 110,000 year-old Neanderthal from Denisova Cave.
“By combining these new insights from archaeology and genetics, we can start to piece together the intriguing story of the easternmost Neanderthals and the events that shaped the history of our ancient human relatives,” Dr. Kolobova said.
The results were published in the Proceedings of the National Academy of Sciences.
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Kseniya A. Kolobova et al. Archaeological evidence for two separate dispersals of Neanderthals into southern Siberia. PNAS, published online January 27, 2020; doi: 10.1073/pnas.1918047117
Source link: https://www.sci.news/archaeology/chagyrskaya-neanderthals-08059.html
