Abstract:

Although recent studies have provided crucial insights into the population genetic history, spatiotemporal distribution, and morphology phenotype of Denisovans, a conspicuous research gap still exists in southwestern China. Moreover, Denisovan postcranial remains are scarce, particularly lacking diagnostic long bones. These research gaps limited our understanding of the spatiotemporal distribution and morphological phenotype of Denisovans. To identify more hominin fossils, a research team led by Qiaomei Fu from the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, in collaboration with several archaeological institutions or universities, conducted comprehensive morphological screening of over 60,000 bone fragments from Bianfu Cave in Yunnan Province. Among these specimens, 76 were selected for Zooarchaeology by Mass Spectrometry (ZooMS) analysis, and subsequently, 17 were subjected to proteomic sequencing. A total of 3 new ancient hominin fossils were identified, including two parietal fragments and one distal radius fragment, whose stratigraphic ages dated to approximately 167~134 thousand years ago. Single amino-acid polymorphism analysis and phylogenetic analysis confirmed that both the newly discovered hominin bones and two hominin teeth unearthed during excavation belong to Denisovans. These findings make Bianfu Cave to be a site with the richest variety of Denisovan remains outside Denisova Cave in Siberia. This study fills a critical geographic gap in the known distribution of Denisovans, deepens our understanding of their evolutionary history, and sheds new light on their postcranial phenotype.

Key words: Denisovan, paleoproteomics, Bianfu Cave, Northwest China