Paper short abstract:

The demographic transition throughout prehistoric East/Southeast Asia is explored using batteries of nonmetric dental traits. Agriculturally driven demic expansion during the Neolithic, associated with genetic exchange with pre-existing hunter-gatherers, is demonstrated.

Paper long abstract:

Eastern Eurasia is believed to have been occupied by anatomically modern Homo sapiens (AMH) from at least 60kya, followed by near simultaneous dispersals from the southern region into sub-continental Sahul. AMHs occupying the northern region colonized the Americas much later, after 20kya. Elucidating the biological relationships between early AMH colonizers and the present-day inhabitants of the region is fundamental to resolving questions surrounding the migration history of this area. Non-metric dental trait analysis provides a powerful tool for mapping out the genetic landscape of past and present day East/Southeast Asia. This study, using dental data sets spanning the late Pleistocene through to Neolithic (and later) periods, demonstrates an apparent genetic discontinuity between pre- and post-Neolithic populations. Events occurring during the Neolithic, it would seem, were pivotal in terms of the micro-evolutionary history of this region. Moreover, we demonstrate a close affinity between pre-Neolithic Hoabinhian and Australo-Melanesian samples on the one hand, and a northern source for contemporary Southeast Asians on the other hand. We argue that pre-Neolithic foragers descended from the first AMH colonizers of Southeast Asia, sharing common ancestry with present-day Australian Aboriginal and Melanesian populations. The eventual outcome of this was large scale integration with a population-language-agriculture dispersal package originating to the north in East Asia, ultimately contributing to the modern Southeast Asian morphology.