Nonmetric Cranial Variation Research Articles

Nonmetric cranial variation of Jomon Japan: Implications for the evolution of eastern Asian diversity

The purpose of this study is to investigate the origin and expansion of the Jomon population, the Neolithic inhabitants of the Japanese archipelago, and peopling East/Northeast Asian region through a global comparison between the prehistoric samples from around the world. R-matrix approach was applied to 20 nonmetric cranial traits for assessing the population structure and history of the Jomon. Pattern of ancient group relationships on a global scale was presented using network splitstree applied to distance matrix transformed from the R-matrix. The phenotypic variation is largest in Hokkaido region, followed by the regions of eastern Japan. The Chugoku region, the southwestern part of Japan, shows larger variance than eastern Japan. Global analyses including samples from Northeast Asia, Southeast Asia, Australia, West Asia, Europe, and North Africa dating roughly to the same chronological periods as those of the Jomon groups, indicate northern affinities of the Jomon and the distinction between Southeast and Northeast Asian series. The Jomon ancestors of the northern part of Japan might have expanded southward to Honshu Island with a series of bottlenecks. A possible gene flow from outside source or heterogeneous origin of western Jomon group was, at the same time, suggested. The network relationships of the Jomon with Northeast Asians and, to a lesser extent, with Southeast Asians based on the splitstree analysis may allow us to suppose that the Jomon may be one of the key populations for the studies of the evolution of eastern Asian diversity.

Nonmetric cranial variation in human skeletal remains associated with Okhotsk culture

Population affinities and biological variation in human skeletal series associated with the Okhotsk culture from Hokkaido and Sakhalin Islands from the 5th to 12th centuries AD are investigated using 19 nonmetric cranial traits. The Okhotsk crania have a higher frequency of the supraorbital foramen than the Hokkaido Ainu and Jomon, while the frequency of the transverse zygomatic suture vestige in the Okhotsk is as high as in the Jomon. The mean measure of divergence between the northern and eastern Okhotsk cranial assemblages is small and insignificant. The method of Relethford and Blangero [Relethford J.H. and Blangero J. (1990) Human Biology, 62: 5–25] suggests that the eastern Okhotsk had a larger Rii value (distance from the centroid) and a lower observed variation than the northern Okhotsk, indicating that the eastern Okhotsk lost phenotypic variability. These results further reaffirm the affinity between the Okhotsk skeletal series and Northeast Asian series such as the Neolithic Baikalian and Amur. Finally, the results of analyses of nonmetric cranial variation demonstrate a close relationship between the Okhotsk, Ainu, and Jomon series that suggests that the Jomon and Ainu were closer to the Okhotsk than to other Northeast Asian series prior to any admixture.

Nonmetric cranial variation of early modern human skeletal remains from Kumejima, Okinawa and the peopling of the Ryukyu Islands

Nonmetric cranial variation of the Ryukyuans, including the Kumejima population, and their neighboring peoples was investigated. Among the populations compared, incidences of supernumerary ossicles in the Ryukyu series were high. The frequency of the supraorbital foramen of the Kumejima series was shown to be intermediate between those of the East Asians and Ainu. Mean measures of divergence (MMDs) based on 16 nonmetric traits showed that Kumejima is closest to Okinawa, Sakishima, and Amami, as well as to the Philippine and Yayoi groups. The four Ryukyu groups were the most distant from the Hawaii population. Multidimensional scaling and neighbor-joining methods were applied to the distance matrix to represent the relationships among populations. The four Ryukyu groups grouped together with the Yayoi to form a cluster, which was positioned between the East and Southeast Asians and the Jomon-Ainu populations. This suggests that there were not only northern, but also southern influences on the Ryukyu Islands during prehistoric and historic times, as suggested by recent genetic studies.

Cranial variation in prehistoric human skeletal remains from the Marianas.

Nonmetric cranial variation and facial flatness of the Pacific and circum-Pacific populations are investigated. The peoples of the Marianas, eastern Polynesia and Hawaii form a cluster and show affinities in terms of nonmetric cranial variation with the Southeast and East Asians rather than with the Jomon-Ainu, a view which is widely supported by others. Facial flatness analysis also indicates that Polynesians have different patterns of facial prominence as compared with the Jomon-Ainu. These results increase the difficulty of accepting the Jomon-Pacific cluster proposed by Brace and his coworkers. Although genetic and nonmetric cranial variation reveal relatively close relationships, the Mariana skeletons are markedly different in facial flatness and limb bone morphology from those of Polynesians.

Metric and Nonmetric Cranial Variation of the Prehistoric Okhotsk People.

Metric and nonmetric cranial characters of human remains of the prehistoric Okhotsk culture (Okhotsk people) were investigated for evidence bearing on their affinities. The cranial morphology of the Okhotsk people shows standard characteristics of the Neolithic or later Northern Mongoloids. The multivariate analyses suggested that the Okhotsk show close affinities not with the Arctic peoples or inland peoples called the ‘Central Asian group’, but with the peoples in the Amur and Sakhalin. We can not positively identify the specific ancestors of the Okhotsk people, however, because few prehistoric human skeletal remains have been recovered in the Amur and Sakhalin areas. Although the craniometric analysis showed a considerable difference between the Ainu and Okhotsk peoples, the nonmetric cranial variations suggested that the Ainu were originally closer to the Okhotsk than to other Northern Mongoloids even before any admixture.

Nonmetric Cranial Variation of Northeast Asians and Their Population Affinities.

A comparative study of nonmetric cranial variation revealed population affinities between the Northeast and East Asians. The recent eastern Siberian populations were basically divided into the three groups defined by Debets (1951), though the Baikal group peoples, consisting of the Amur, Evenki and Yukagir, do not cluster together. The Yukagir remain intermediate between the Baikal and Central Asian groups, while the Evenki are isolated from other Siberians, probably because of their small sample size. The Neolithic Baikalian are close to the Amur peoples, while the Troitskoe of the Mo-ho culture from the Amur basin show some close affinities with the Central Asian group. Because the Central Asian group peoples are more similar to the Northern Chinese than to the Neolithic Baikalian, the former two seem likely to have interacted with each other since the Neolithic age. The Hokkaido Ainu show no close affinity with the Neolithic or the later Siberian Mongoloids, nor with the Europeans.

Nonmetric cranial variation and biological distances between samples of six nontribal populations of India

Sixty-nine nonmetrical morphological variants of the cranium have been studied in six samples of non-tribal, state populations in India, and their incidence reported. Using C.A.B. Smith’s angular transformation of frequencies, the multivariate Thetasquare distances and their respective standard deviations have been presented. On the basis of nonmetrical cranial variation, it is clear that the samples from Uttar Pradesh, Andhra Pradesh and Bihar are closer to each other but distant from Madhya Pradesh, Karnataka and Maharashtra. On the other hand, Karnataka and Maharashtra samples are quite close to each other and both, in turn, are comparatively closer to Madhya Pradesh than to Uttar Pradesh, Andhra Pradesh and Bihar. Madhya Pradesh sample emerges as the most divergent group among the six population samples studied. This, in general, is in conformity with the picture that emerges from various analysis of morphometric and other biological data on various populations of India.