The study, "Ancient DNA and multimethod dating confirm the late arrival of anatomically modern humans in southern China," refutes the hypothesis of early settlement of southern China by anatomically modern humans (AMH) up to 120,000 years ago. The authors analyzed human remains from five caves (Fuyan, Yangjiapo, Huanglong, Luna and Sanyou) using multi-method geological dating and ancient DNA (aDNA) analysis, including direct AMS ^14C dating and sediment and infiltration dating using OSL and U-Th methods. The results showed that earlier dating based on the U-Th method of cave infiltration (flowstones) greatly overestimated the age of human remains - they were assigned an age of 120-80,000 years, while the actual dates based on aDNA and ^14C indicate the Holocene period (less than 16,000 years ago). In Fuyan and Yangjiapo, mtDNA samples showed affiliation with modern Eurasian haplogroups (e.g., D4b2b5, B4a4a, B5b2c), and their separation times were estimated to be 1-16 thousand years ago. Direct radiocarbon dating confirmed the young age of human teeth: Fuyan (about 3,700-12,000 years ago), Yangjiapo (about 2,400-7,600 years ago). The authors showed that the cave deposits are much more complex than previously assumed, with numerous phases of erosion, redeposition and intrusion of bone material, often much younger than the surrounding sediments and flowstone. In only one of the five caves did the age of the sediments agree with the age of the flowstones, and in the others the discrepancies reached orders of magnitude. At Sanyou, a human tooth was dated by the AMS method to only 1.7-1.6 thousand years ago. The study's conclusions suggest that the earliest currently confirmed AMH traces in southern China date back to a maximum of 35,000 years ago, rather than 80-120,000 years ago, as previously thought. These findings are consistent with molecular genetic data indicating the expansion of AMH from Africa into Eurasia between 65,000 and 45,000 years ago. The authors call for the routine use of direct dating and aDNA methods in paleoanthropological cave studies to avoid misinterpretations resulting from reliance on single dating techniques.
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