[in Japanese]

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Northern Kyushu, the area of Japan located closest to the Korean Peninsula, has been considerably influenced by foreign culture and immigrants from the Asian mainland in the past. Numerous morphological studies of human skeletal remains from the Jomon and Yayoi Periods in this region have shown that a variety of physical characteristics of the Yayoi are greatly different from those of the Jomon. The observed physical differences between the Jomon and Yayoi peoples has been attributed to a genetic influx of immigrants from the Korean Peninsula or China.
However, several important questions require further scrutiny concerning with the tran-sition from Jomon to Yayoi peoples, especially in the early stages of the supposed immigra-tion into this region. The main difficulty in solving these questions concerning with the transition during these periods in the northern Kyushu has been the lack of suitable skeletal materials belonging to the time between the two periods, i.e. the final Jomon and the early Yayoi Periods. Most of the Yayoi skeletons collected so far in this region represent the middle Yayoi period. Material from the early stage of the Yayoi Period or final stage of the Jomon Period is totally lacking. Therefore, we know few details of the transitional period. For example, it is unclear when the new physical features associated with Yayoi people first appeared in this region, or who the first rice agriculturalists in Japan were. In other words, which group of people is responsible for the “Yayoi revolution”, including new culture and full scale rice agriculture, the native Jomon people or a new immigrant group? In recent years, a number of archaeologists have favored the former group as being responsible. Clarification of the people who opened the door to the new cultural stage, i.e. the Yayoi Periods, is critical when attempting to discuss the origin of the Japanese.
Because it is difficult to discuss this problem directly due to scarcity of skeletal remains from these periods, we attempt a reconstruction of this transitional period in northern Kyushu, by paleodemographic and morphological analyze. The features of the Yayoi skeletons ex-cavated from northern Kyushu (almost all belonging to the middle Yayoi Period) show strong resemblances to the ancient people of the Asian mainland such as those from the Yean-ri site in southern Korea and the Linzi site on Shandong Peninsula, rather than an intermediate morphology which would have resulted from a mixture one of immigrant and native Jomon peoples. The results of discriminant function analysis of Yayoi crania also show that the immigrant-type Yayoi people represents the majority of inhabitants of this region and only 10-20% of the Jomon-type. It is difficult to reconcile this lop-sided ratiofor the inhabitants in the middle Yayoi Period with archaeological interpretations which view the native Jomon people as mainly responsible for the transition from the Jomon to Yayoi Period. If it was the case, the native Jomon people increased their population size, and then, the majority of the human skeletal remains from the sites representing the middle Yayoi Period should be predominantly Jomon-like people. However, the excavated skel-etal remains from northern Kyshu demonstrate the opposite.
On the other hand, many archaeological studies in this region suggest that the number of immigrants from the Asian mainland should represent a minority group in comparison with the native Jomon people. This implies that the immigrant minority group at the beginning of the Yayoi Period eventually expanded to become the majority (80-90%) in northern Kyushu 200-300 years later. This remarkable change in the physical characteristics of the inhabitants of this region can be explained if the growth rate of immigrant group was suffi-ciently higher than that of the native people. For example, it is estimated that a population growth rate of 1.3% per year is necessary for the

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The equations most commonly used to estimate the stature of Japanese females are those reported by Fujii (1960). The number of samples is, however, not enough. In the present study, the datasets obtained from 21 cadavers were combined with those provided by Fujii (N = 27) for presenting statistically more reliable stature estimating regression equations for modern Japanese females. In the evaluation of the residual between actual stature and estimated stature, and of the discrepancy between estimated statures based on each of long bones, an improvement of the estimates can be observed for the present formulae. The residuals based on the least square method follow the pattern exhibited by several studies, overestimating stature of very short individuals and underestimating stature of very tall ones. For an improvement of the accuracy of the estimate, the equations using major axis and reduced major axis were calculated. The application of these requations bears evidence that the major axis method leads to lower degrees of error in both short and tall individuals. This indicates that major axis regression techniques are useful when the stature is estimated for very short or very tall individuals.

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