Genomic studies initiated at the end of the 20th Century reached one peak when the human genome was sequenced. It was, however, not the end, but the starting point. Studies based on enormous numbers of SNP and microsatellite DNA polymorphism exploded, and a new light also shines on genetic diversity of people of Japanese Archipelago, while confirming results based on small scale classic polymorphic markers. Sequencing individual human genomes is also going on. These new horizon of human genomics was introduced.

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We performed three-dimensional analysis of the morphological variations of the craniofacial form in the Jomon and modern Japanese populations by using geometric morphometrics to explore if this approach is actually able to reproduce previously described morphological features, and to detect possible new patterns of craniofacial variations among the population groups. The sample comprised 19 Jomon (10 from Tsukumo and 9 from Yoshiko shell mounds) and 22 modern Japanese specimens housed at Kyoto University, Japan. Each cranium underwent computed tomography and virtual models were generated. Variability in cranial shape was then examined using a geometric morphometric technique based on landmark coordinates. Compared to the Tsukumo samples, the cranial shape of the modern Japanese tends to display relatively higher upper face and nose; narrower cerebral and bizygomatic breath; more inferiorly positioned palate and cranial base; more prominent (less flat) face; and stronger alveolar prognathism, indicating that the results of the present analysis based on geometric morphometics are generally consistent with the results of previous studies with conventional multivariate analyses. Furthermore, large differences were detected in positions of the lambda and inion, which are located relatively more anteriorly and posteriorly, respectively, in the modern Japanese, indicating squama occipitalis is more vertically oriented. By use of geometric morphometrics, these morphological variations were statistically extracted and the shape difference was clearly visualized for interpretation. Although the number of well-preserved specimens is generally limited for ancient human skeletons such as Jomon specimens, this study confirmed the efficacy and usefulness of this approach for the analyses of the temporal and regional variability of the craniofacial form in the Japanese populations.

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Determination of sex of human skeletons is a fundamental issue in physical anthropology. The purpose of this study is to develop new standards to determine the sex of fragmentary human skeletal remains from archaeological sites in Japan. In order to accomplish this, we measured the head and neck circumferences of long bones of medieval Japanese skeletons, and provided metric diagnosis of sex using discriminant function analysis. The materials are comprised of human skeletal remains from the Yuigahama-minami site, Kamakura, Japan. The sample size used in this study is 54 males and 51 females, which were excavated from individual burial graves. The accuracy of sex classification is 85.1–93.6% for discriminant functions with only one variable, and reaches 93.9% for those with a combination of two variables. It is noteworthy that new standards allowing for reliable diagnosis are developed with a small number of variables from well preserved parts of the ancient skeletons themselves. The results here will provide reliable diagnostic standards of fragmentary skeletons.

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