Non-metric dental traits of modern human populations reflect not simply phenotypic plasticity but also reflect genetic change. In the present study, sevendiscrete crown characters were observed.
The biological relationships of eleven populations from the Pacific, East Asia and North America are assessed through the application of some distance analyses.The results obtained reveal that the dental characteristics of modern mainland Japanese, the Aeneolithic Yayoi population and Pima-Indians share the classic northern components. Some geographically isolated populations in Japan show, on the other hand, closer affinities to the Neolithic Jomon population, Negritos and the Pacific populations than to modern mainland Japanese.
This is evidence that modern Japanese show considerable magnitude of admixture with one of the groups of the Aeneolithic Yayoi population who migratedfrom the northern part of Asia during the Yayoi period and the succeeding age.On the other hand, the Proto-Mongoloid population of late Pleistocene Southeast Asia gave rise to the Neolithic Jomon population, and then to native Japanese.
As far as the dental characteristics are concerned, Negritos may be one of the possible representatives of groups through which the basic population in Japan have passed. Based on these findings, a dental anthropological model of population diversification in East Asia and the Pacific was discussed.