19. Human Genetic Diversity in Eastern Asia
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I: Australoid
II. Proto-Amerind
Northern Mongoloid
IV: Southern Mongoloid
Fig. 7. A model of the origin and dispersal of eastern Asian populations, assuming at least
two independent sources for migration since the Upper Paleolithic Time (Ornata 1995)
It is also noted that among the Asian-Pacific populations, there are essentially
two genetically separate cluster groups, namely the northern and the southern groups.
Although the "bootstrap" probability between the two clusters is not high and statistically insignificant, it may be hypothesized that this dichotomy was present in
the past. It is known that there was a large-scale migration of the Austronesian
speakers from the Asian continent to the Pacific about 6000 years ago (Bellwood
1979). They were pushed out from what is now China, probably by the population
expansion of northern groups.
Based on these findings, I have put forward an alternative model of "Mongoloid" origin, which I refer to as Model 3 (Omoto 1995). This model assumes that