Non-metric dental traits of modern human populations reflect not simply phenotypic plasticity but also reflect genetic change. In the present study, sevendiscrete crown characters were observed.
The biological relationships of eleven populations from the Pacific, East Asia and North America are assessed through the application of some distance analyses.The results obtained reveal that the dental characteristics of modern mainland Japanese, the Aeneolithic Yayoi population and Pima-Indians share the classic northern components. Some geographically isolated populations in Japan show, on the other hand, closer affinities to the Neolithic Jomon population, Negritos and the Pacific populations than to modern mainland Japanese.
This is evidence that modern Japanese show considerable magnitude of admixture with one of the groups of the Aeneolithic Yayoi population who migratedfrom the northern part of Asia during the Yayoi period and the succeeding age.On the other hand, the Proto-Mongoloid population of late Pleistocene Southeast Asia gave rise to the Neolithic Jomon population, and then to native Japanese.
As far as the dental characteristics are concerned, Negritos may be one of the possible representatives of groups through which the basic population in Japan have passed. Based on these findings, a dental anthropological model of population diversification in East Asia and the Pacific was discussed.

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Seven sutural and two foraminal non-metric characters were studied in ancient and recent skulls from Japan and surrounding areas. Variation of threeprincipal traits in most groups can be best explained by a mixture of two components, Jomon and Mongoloid, the latter one increasing in the following order: West Jomon people-East Jomon people-Hokkaido Ainu-Sakhalin Ainu-Ryukyuans -Yayoi people-Kofun people-West Japanese-Tokyo Japanese. In theJapanese and their ancestors beginning from the Yayoi period, the Mongoloid component is very similar to the one represented in modern Chinese. Its introduction to Japan in Yayoi times was abrupt and obviously caused by massive immigration.The further increase of Mongoloid traits from Yayoi to modem times was slow. Traces of Jomon (or Ainu) substratum are seen in all modern Japanese groups which is probably due to an early shift of West Jomon populations to agriculture and their mixture with the immigrants. The Okhotsk group of Hokkaido shows an unusual combination of Tunguso-Manchurian and Ainu features.

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Incidence data of cranial nonmetric traits were analysed in eight population samples from Japan, ranging in age from 4, 000 B.P. to the present time. The trait frequencies were extremely homogeneous in the Japanese samples during the last 600 years from early medieval to modern times when no significant gene flow from overseas was evident in Japan. It was inferred that the incidence pattern of cranial nonmetric traits faithfully reflected the Japanese genetic constitution of historic times.SMITH's Mean Measures of Divergence (MMDs) based on the incidence data of 20 nonmetric traits between the protohistoric and historic Japanese samples were statistically insignificant, whereas those between the Neolithic Jomon and the foregoing Japanese samples far exceeded the significance level of 0.01. The MMDs as well as the cluster analysis and principal coordinate analysis of MMDs suggested that (1) there existed population discontinuity between the Jomon and the protohistoric Kofun people; (2) the Aeneolithic Yayoi period was a phase when a number of different populations - natives and immigrants from the Continent - were struggling for their dispersals; (3) genetic constitution of the immigrants had predominated over that of the natives by the end of the Yayoi period and as a result the direct ancestral population of the modern Japanese was stablished during the protohistoric Kofun period. As for the Jomon and Ainu, their close affinity was demonstrated.

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One of the possible causative factors of the increasing trend of temporomandibular joint problems in recent years, is the evolutionary reduction and decreased growth of the human masticatory system. The purpose of this study was to investigate the secular reductive changes in this joint in Japanese people.
Materials used were 279 X-ray cephalogramsof Japanese crania from the Jomon, Yayoi, Kofun, Kamakura, Muromachi, Yedo and Meiji periods, and 419 X-ray cephalograms of living Japanese obtained from 6 areas. Linear measurements of 7 items, i. e. condylar process height, condylar process basal width, mandibular neck width, condylar width, condylar height, articular fossa width and articular fossa depth were carried out. Secular changes were analyzed for these measurements using the t-test and rank correlation.
Jomon people had prominent condylar processes with wide condylar width. The condylar processes became longer in the Yayoi period. In addition, the width of condyles and mandibular necks were slightly reduced and condylar heads became narrower. The articular fossa, on the other hand, became both wider and deeper. This indicated that the ratio of condylar width to fossa width became smaller, resulting in a morphological disharmony between the condyle andarticular fossa. In the Kofun period, the condylar and mandibular neck widths reached their maximum and the condylar process became thicker and more sturdy. At the same time the articular fossa width decreased slightly, but the size and depth of the fossa remained appropriate for the condylar head. Thus, the size of the condyle and of the articular fossa were proportional. In the Kamakura period and Muromachi period, the condylar processes became shorter whilst the condylar and mandibular neck widths became slightly narrower. Moreover, both the width and depth of the articular fossa began todecrease. From the Yedo period to the present, marked morphological changes have occurred.For example, the condylar process has become thinner and more delicate and the top of the condyle more narrow. In contrast, the articular fossa has tended to increase both in width and depth until the present. As a result of these changes, a morphological disharmony of the temporomandibular joint, (i.e., a narrower condyle than articular fossa), has become apparent.
As a general trend, secular changes of the joint structure have been observed on the condylar process, whilst the changes of the articular fossa have shown no such definite tendency. The condylar process had a tendency to become more slender with time, and the condylar width showed highly significantly diminution. Of considerable interest was the significant decrease in the ratio of condylar width to the fossa width in the Yayoi and modern period.

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The purpose of the present study was to analyze physical fitness and motor ability of 12 to 17 year-old children (3, 948 boys and 3, 901girls) examined in 1986 in terms of the nine grades of the stout-lean index. The index was obtained when their own body weight was divided by the mean body weight by sex, age and standing height in the report of the Ministry of Education, Science and Culture, and the quotient was multipled by 102. The nine grades of the index were composed of the 1st (-84), the 2nd (85-89), the 3rd (90-94), the 4th (95-99), the 5th (100-104), the 6th (105-109), the 7th (110-114), the 8th(115-119) and the 9th (120-). Their physical fitness data (side step test, vertical jump, back strength, grip strength, step test, trunk backward extension, standing trunk flexion) and motor ability data (50m sprint, running broad jump, handball throw, pull-ups, endurance run) were classified by the nine grades of the stout-lean index. The author ran a one-way analysis of variance on these data and analyzed all possible pairs of difference between the sample means by the SCHEFFÉ's method of multiple comparisons.
The major results were as follows:
1) In every age group, the F-ratios in the analysis of variance of grip strength, 50m sprint, running broad jump and endurance run in both sexes, and back strength, pull-ups of the boys were significant at the 0.05 level or the 0.01 level. However, the F-ratios in the analysis of variance of trunk backward extension of the girls were not significant.
2) The F-ratios in the analysis of variance of handball throw in both sexes, side step test, vertical jump and step test of the boys, and back strength of the girls were significant at the 0.05 level or the 0.01 level for more than two thirds of six age groups. Meanwhile, the F-ratios in the analysis of variance of standing trunk flexion in both sexes, trunk backward extension of the boys, and side step test, vertical jump, step test and pull-ups of the girls were not significant for more than half of six age groups.
The seven physical fitness items and the five motor ability items were grouped into five types according to the results of a test of significance by the SCHEFFE's method.
3) In the A type (50m sprint, running broad jump and endurance run), the records became significantly lower in proportion to the degree of stoutness from the seventh grade to the ninth grade of the stout-lean index.
4) In the B type (back strength and grip strength), the records became significantly lower in proportion to the degree of leanness from the fourth grade to the first grade of the stout-lean index.
5) The C type (vertical jump, side step test, step test and pull-ups) was a variation of the Atype. The records became significantly lower in the eighth and ninth grades of the stout-lean index in specific age groups. Especially the records of the boys showed a marked drop in the ninth grade of the stout-lean index.
6) In the D type (handball throw), the recordsbecame significantly lower in the first and secondgrades of the stout-lean index.
7) In the E type (trunk backward extension), there were a few significant differences betweenthe sample means of the boys in the most age groups.

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This paper analyzes a historical document, shumon aratame-cho, and examines a change in nuptiality and fertility of a village (Yambe) in Northeastern Japan during the latter half of the Tokugawa period. The following is a summary of the main findings of the paper.
Marriage showed different patterns between sexes in Yambe. For males, both age at first marriage and the proportion ever-married were strongly influenced by economic factors, either changes over time or differences between classes, whereas this was not necessarily true for females.In other words, age at first marriage and the proportion ever-married for males were closely related to changes in employment opportunity and income level. On the other hand, these two indices for females were more stable throughout the period, fluctuating in a narrower range. A similar pattern can be found in the relationshipbetween socio-economic status (SES) and nuptiality. Namely, among Yambe men, both age at marriage and the proportion ever-married were negatively associated with SES, but the clear relationship cannot be found among Yambe women.
Three possible reasons for this different pattern between sexes are offered in this paper.First, marriage for females was more culturally determined (e.g., social norm) than for males.Second, groom's economic well-being and contribution were more crucial to marriage than those of the bride. And, in general, bride's economic contribution to the household of her husband was relatively small except for her labor contribution. This may be a common feature of patrilocal society. Third, the demand for male labor was higher than the demand for female labor, and wages for male servants were muchhigher than wages for female servants. As a result, economically men had more control over their own marriage than women did.
Fertility of Yambe women increased over time. Particularly, a sharp increase was found in the age group 25-39. The increase in fertility was resulted mainly from an increase in marital fertility. A decrease in celibacy rate also conributed to the fertility increase, although this effect appears to have been smaller than the effect of marital fertility. A clear relationship between fertility and SES cannot be found. Then the paper discusses the possible causes of the increase in marital fertility from the standpoint of proximate determinants and economic value of children.
Besides marriage, two proximate determinants are likely to have made an impact on fertility of Yambe women: the duration of postpartum infecundity and a behavioral aspect of fecundability. Increased infant and child mortality shortened the duration of postpartum amenorrhea, which resulted in shorter birthintervals. And the exposure of women to the risk of childbearing, more precisely coital frequency, increased along with the transformation of labor from hokonin (live-in servants) to day laborers.In addition, an increase in employment opportunity and wage is likely to have lowered the frequency of infanticide and induced abortion. At the same time, wealth began to flow from children to their parents, so that the parents came to have a strong incentive for children.

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Dental characteristics of Atayal, one of the Taiwan aborigines, were compared with those of Mokapu, Marquesas, Guam, Negrito, Okinawa, Aogashima, Ainu, Jomon, modern Japanese and Yayoi (Doigahama) reported by K. HANIHARA (1976) and T. HANIHARA(1989a, b, c; 1990a, b).One dimensional expression based on PENROSE'S size distances shows that the overall tooth size of Atayals is largest next to Guam among the populations compared and close to modem Japanese and Yayoi. As regards the shape factor based on mesio-distal crown diameters, Atayal is closely related to modern Japanese and Yayoi as shown by Q-mode correlation coefficients.These findings are almost the same as the results obtained with metric multidimensional scaling method. On the other hand, SMITH's distances based on seven non-metric crown charactersshovel shape in the upper central incisors, CARABELLI'S cusp in the upper first molars, 6thcusp, 7th cusp, deflecting wrinkle and protostylid in the lower first molars, and +4 pattern in the lower second molars-show close affinity between Atayal and Japanese-Yayoi group. This finding is more evident in the results obtained by cluster analysis and principal co-ordinate analysis. The frequency distributions of the crown characters in Atayal correspond to the sinodonty in TURNER's (1987) term.
Both results based on metric and non-metric data of dental morphology reveal that Atayal shows a close affinity to modern Japanese and Yayoi in one hand, and to the populations of mainland China and northeastern Asia in another.
In the future, more populations-other tribes of Taiwan aborigines, Taiwan Chinese and the populations surrounding Taiwan-should be analyzed in combination to elucidate affinities ofTaiwan aborigines.

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Variation of a red cell enzyme, S-adenosyl L-homocysteine hydrolase (SAHH) was surveyed among 640 Japanese individuals from four different localities.According to the typing after starch gel electrophoresis, all samples were SAHH 1 and no variant could be detected. These results were inconsistent with those of AKIYAMA et al. (1984), who reported polymorphism of the enzyme among Japanese.Control testing using Caucasian samples and panel red cells obtained from the USA, however, indicated that variant types were detectable and that the typing proceduresused in the present study was appropriate.

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Information about subcutaneous fat distribution over the entire body is important for clothing design as applied anthropology. The measurement of subcutaneous fat thickness by ultrasonic tomogram overcomes the limitations of skinfold calipers measurement, but its accessibility varies depending on easiness of identifying the fat-muscle interface at the measuring sites. This study examined accessibility of ultrasonic tomograms at 22 body sites in 58 young adult females.Individual differences in the tomographic image at such sites as the triceps, plural echoes from the fat layer at such sites as the trochanter, and the "dead time region"at such sites as the wrist, make the identification difficult. The 22 sites were classified into three groups according to their accessibility to measurement. Seventeen sites were confirmed to be measurable, including the sites such as the buttock and thigh whichare indispensable to the study of the apparent characteristics of the human body and obesity/leanness as a basis for the designing of comfortable clothing. The sites such as posterior neck and posterior sulcus were not considered to be accessible.

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