The Origin and Microevolution of Ainu as Viewed from Dentition: The Basic Populations in East Asia, VIII

Metric and non-metric dental variation among several Ainu samples was analyzed. Recent Ainu samples from Hokkaido and Sakhalin form a tight cluster. The sample from the people of the Okhotsk culture, or Omisaki sample, shows a quite dispersed arrangement. Extending the comparisons to include East and Southeast Asian and the Pacific samples validates the relatively homogeneous dental pattern of recent Ainu. The Omisaki sample has dental characteristics similar to those of sinodont populations. Discriminant function analyses based on metric and non-metric data indicate that some Omisaki individuals are classified as part of the members of sundadont populations, and others as those from sinodont populations. These findings suggest that the people of the Okhotsk culture were likely migrants from the north. However, they might have exerted little genetic influence on the formation of the physical characteristics of recent Ainu. The results obtained in the present study re-confirm that Ainu may be direct descendants of the Neolithic Jomon people. They share the ancestral ties with the generalized Asiatic populations, as represented by Negritos. It is quite likely that members of the late Pleistocene Sundaland populations could have colonized the continental shelf of East Asia, extending to Hokkaido and Sakhalin in the north and western Micronesia and Polynesia in the east.