To investigate the occurrence of transverse lines in long bones of adults, we studied 27 cadavers (14 males and 13 females) used for teaching anatomy, and took a roentgenogram of the femur and tibia. After confirming the presence of a transverse line, a cross-sectional sample was examined macroscopically, and by soft X-ray and scanning electron microscopy. The following results were obtained: 1) According to roentgenograms, transverse (Harris') lines were observed in 40.7% of the distal half of the femur and in 29.6% of the proximal half of the tibia. These showed a strong tendency for bilateral symmetry as is characteristic of transverse lines and the frequency was much higher than previous reports suggested. 2) Macroscopic examination of the bone cross-sections at the level of the transverse line showed membranous structures of various morphologies, ranging from complete interruption of the medullary space to a washer-like appearance, or the structures were formed by joined trabeculae. The frequency of detection may vary according to the observation method. 3) In scanning electron micrographs, matrix fibers were observed on the surface of trabeculae. The transverse lines were clearly formed from osteoblasts. No marked difference in structure was observed between the transverse line trabeculae and the compact bone. 4) From these facts, we considered that further studies are necessary to examine the age-related changes of the transverse lines and the significance of their presence in adults.

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We studied temporal changes in the stature and limb characteristics of western Japanese during the Jomon to Edo periods for comparison with those of Kanto Japanese (Hiramoto, 1972; Yamaguchi, 1986), and to establish norms for Japanese from both regions. Stature was estimated by the formulae of Fujii, Pearson and Trotter/Gleser based on 686 femora, 582 tibiae, 558 humeri and 569 radii from a total of 511 samples. The leg index was based on 334 lower limbs, while the forearm index was on 284 upper limbs.
Stature based on the femur/humerus increased markedly between the Jomon and Yayoi periods, and then decreased between the Yayoi and medieval periods. In contrast, stature based on the tibia/radius, after increasing slightly between the Jomon and Yayoi periods, decreased gradually during the Yayoi to Edo periods. On the other hand, the leg and forearm indices decreased between the Jomon and Yayoi periods, were maintained between the Yayoi and medieval periods, and then again decreased between the medieval and Edo periods. These results imply that increases in the stature between the Jomon and Yayoi periods result from elongations of both the femur and tibia, while decreases in the index result from elongation of the femur/humerus beyond the tibia/radius. We also found that the stature of Japanese from both western and Kanto regions had changed similarly from the Jomon to Edo periods.

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Dental casts were recently collected from Highlanders in Kasi Village of Wabag in Enga Province of Papua New Guinea (PNG). Mean age of subjects was 19.2 years ranged from 16 to 44. The mesiodistal and buccolingual diameters of all upper and lower teeth (except third molars) were measured. Sex differences of these diameters were relatively large in this population compared with other Pacific populations. The results were compared with previous reports of Asian Pacific populations including some Highland groups of PNG by cluster analysis and multi-dimensional scaling from Mahalanobis' distances, Q-mode correlation coefficients and Penrose's size distances. In the Mahalanobis' distances, Wabag was clustered in the groups of Melanesians and Australian Aboriginals. In the analysis of the distances transformed from Q-mode correlation coefficients, Wabag was also clustered with these groups, but Fiji was clustered in Polynesians and Micronesians. In the Penrose's size distances, Wabag teeth were smaller than other Highlanders such as Goroka and Lufa, but were close to Polynesians. This suggested that tooth size varied in a Highlander groups in PNG and that there were marked polymorphism of Melanesians.

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Following the method of Yamaguchi (1973), a series of facial flatness measurements were taken from crania from the islands of Amami, Okinawa and Sakishima of the Ryukyu Islands. These measurements were compared with each other and with measurements of cranial series from other Japanese Islands, insular and continental Northeast Asia and Europe. Among the three Ryukyuan samples, the facial skeletons of Sakishima are least flattened. Nevertheless, the Ryukyuans as a whole show far flatter faces than Ainu. The extent of Ryukyuan facial flatness is comparable to that of the so-called “Northern Mongoloid”. In addition to the previous cranial nonmetric study (Dodo and others, 1998), the present study of facial flatness also does not give any indication of a close affinity between the Ainu and Ryukyuans.

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House mice are apparently more likely to mate with individuals dissimilar to themselves at MHC (major histocompatibility complex) loci than with similar individuals. Such negative assortative mating is thought to be mediated by olfaction. Recently, it has been suggested that huma mate choice may be affected by HLA (human leukocyte antigen; MHC in humans), based on the finding that women prefer the odor of men dissimilar to themselves at HLA loci to that of HLA-similar men. If these odor preferences are indeed an important criterion of mate choice in humans, actual marriages may show negative assortment with respect to HLA. In this paper, we compared the observed similarity between spouses at HLA loci with the expected similarity under random mating, for about 150 couples from 6 prefectures in the Tohoku region of Japan, and for about 300 couples from 16 prefectures all over Japan. For statistical tests, we used empirical distributions of goodness-of-fit statistics, X² and G, obtained by Monte Carlo methods, because these statistics may not follow the chi-square distribution. Tests for each sample as a whole and for each prefecture rule out strong disassortative mating at the HLA-A and HLA-C loci.

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In order to examine the characteristic of the dental arch of the Chaoxian, the dental arch of three populations (Chaoxian, Han, and Man) in Liaoning Province of China, the Koreans and the Japanese morphological characteristics were observed and measured with the same measuring points and methods. The major findings are as follows. 1) The upper posterior dental arch length of the Chaoxian is the smallest among these populations, and significantly different from the other populations, except for the Man. 2) The upper dental arch breadth of the Chaoxian is the largest, and significantly different from the Man and the Japanese. 3) The conclusion from the cluster analyses indicates that the Chaoxian is the closest to the Koreans in the characteristic of the dental arch. Moreover, we also discuss the effect of the difference on the dental arch, and put forward that the difference on the characteristic of dental arch mainly comes from genetic factor.

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