Abstract
In this study, we evaluate the regional differences among three local Hokkaido Ainu groups (of southwest, central, and northeast Hokkaido) and the Sakhalin Ainu in terms of the frequencies of 20 nonmetric cranial traits. The degree of regional difference is measured by Smith’s mean measure of divergence (MMD). The mean regional difference among the three local Hokkaido Ainu groups is slightly larger than that among the early modern peoples of the three Ryukyu Islands—the Amami, Okinawa, and Sakishima Islands—, and it is almost equivalent to that of the three mainland Japanese groups composed of the modern peoples of Tohoku, Kanto, and Kyushu districts. Among the three Hokkaido Ainu local groups, the northeast group is slightly different from the southwest and central Hokkaido groups. The mean regional divergence between the Sakhalin Ainu and Hokkaido Ainu is four times larger than that among the three local Hokkaido Ainu groups. The relations among the three local Hokkaido Ainu groups and the Sakhalin Ainu were also confirmed by Mahalanobis’ D2 distances based on 18 craniofacial measurements.
