Early humans migration and adaptation in the Palaeolithic Tibetan Plateau

 Due to the unique environmental conditions of the Tibetan Plateau, understanding when and how the Palaeolithic ancestors migrated and adapted in the region is a key issue in the course of human evolution. In recent years, along with the increased findings of archaeological evidence and a series of high-level studies, our knowledge regarding the prehistorical human activities on the plateau has been dramatically changed. Evidence from the Baishiya Cave in northeastern plateau have shown that Denisovans occupied the cave since at least 200 ka years ago and stayed in the cave for a relatively longer time. The site of Piluo which is located in southeastern side of the plateau indicates that humans possessing handaxe technology dispersed to the plateau at a time older than 130 ka year ago. In addition, a new lithic technological type called Quina technology has also been identified in the southern part of the Hengduanshan Mountains in Yunnan Province, which is probably related to the emergence of a new human group. Altogether, these findings indicate that different types of archaic humans have ever lived on the plateau. The earliest evidence for the arrival of modern humans is from the Nwya Devu site (~4600 m), given the diagnostic blade products excavated from the site. The site has been dated to ca. 40 ka years ago. Based on current evidence, we propose some possible routes for the migration of humans into the plateau. Denisovans may disperse to the plateau from the northeast direction, handaxe population and Quina population may disperse from the southeastern side, while early modern humans may come from the western side, with two possible sources of Central Asia and Southwest Asia. Overall, it is clear that the Palaeolithic Tibetan Plateau consists of an important region for the exchanges of early humans in different areas. Keywords: Tibetan Plateau, Palaeolithic, Denisovans, Early modern human, Human migration and adaptation