Modern Human Dentognathic Remains From MIS 3–2 of Jianshan Cave, Southern China

The evolution of modern humans in southern China during the Late Pleistocene is still poorly known. Well-preserved human fossils are scarce, and their chronological framework is often unclear or debated. We report two human teeth (M1 and M2) embedded in mandibular fragments from two individuals, recovered from Jianshan Cave. An integrated approach based on a secured stratigraphic and chronological framework has been employed. We test the hypothesis that these teeth exhibit stronger affinities to those of modern humans than to other Late Pleistocene hominins by using morphological comparisons and 3D imaging-based analyses. We applied AMS 14C dating of charcoals, OSL of sediments, and U-series dating of fossils for chronological constraints. Conventional morphological description and metric analysis were used. In addition, diffeomorphic surface matching analyses of the enamel-dentine junction shape were conducted. The Jianshan teeth were dated to 33.5-19.5 ka. All analyses indicate that they belong to Homo sapiens. They exhibit similarities and differences with teeth from other sites, highlighting the morphological diversity of Late Pleistocene humans in southern China. Given the significant differences in lithic assemblages between Jianshan Cave and Bailiandong, it is possible that multiple waves of modern human dispersal in the region occurred during MIS 3-2. With this study, Jianshan joins the short list of MIS 3-2 paleoanthropological sites in attesting to the evolution of modern humans in southern China. More evidence with precise dating is needed before more elaborate interpretations can be proposed.