Traditional approaches to human dental arch forms are mainly focused on categorical classifications and/or parametrizations by applying mathematical functions. In this study I examined intragroup variation of the arch forms, using a multivariate expression newly introduced for the present analysis. The following three components were extracted: 1) the ratio of the width at the canine part to the length at the incisal part, 2) the lateral expansion of the molar part, 3) squareness of the anterior part. On the basis of these results, the classification systems by HRDLICKA and THOMPSON were critically reviewed. My results revealed that these systems are different in character, in that they focused attention on different aspects of the arch form. The merits and demerits of the parametrization were also discussed. Parametrization's merit is the simplicity of its expression; however, when used for classification, the introduction of an artificial order into the arch form variability which is predetermined by an applied function is a demerit. In contrast, multivariate methods can provide natural order for arch variability.

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Characteristics of the changing pattern of the step angle in men during normal walking were studied. On a white paper fixed flat on the floor, 20 healthy subjects aged 18-45 wearing socks soaked with red ink were asked to walk straight to a target 50m away at their optimal speed. All footprints, generally more than 70 in a series, were recorded on the paper without interruption during the experiment. After the step angle was measured with a digitizer, the changing pattern of the angle of the step was examined using Fourier anlysis.
Statistical results revealed that significantlateral differences not only in means but invariances of the step angle were observed in more than half of the subjects. Except for a few subjects, there was a common manner: the angle of the right step was greater and more varied than the left. Fourier analysis indicated that the pattern of step angle change fell into one of the following groups: (1) fluctuation with slow periodicity, (2) fluctuation with medium periodicity, or (3) fluctuation with fast periodicity. Many subjects had a different pattern of angle change between right and left: in 5 subjects this difference was especially remarkable. Their right step angle fluctuated with slow periodicity, while the left step angle fluctuated with fast periodicity. From the results of this study and earlier evidence that step angle is reduced as walking speed increases (MORTON, 1932), it is suggested that many subjects demonstrate a foot preference in normal walking, that is, one side (left in many individuals) is primarily engaged in the decision of the walking direction, and the other side is engaged in the propulsion.

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This study was carried out in order to see the present state of assortative mating among modern Japanese by the method of family line investigation. The author undertook to make a statistical analysis of mate selection by means of factor analysis following anthropometric, sociological and demographic traits of the population. Analyzed by means of husband-wife correlation coefficients for both the first and second generations, the second generation has a tendency toward close resemblance of spouses, especially in stature, as compared with the first generation. The contributive factors in assortative mating were analyzed by factor analysis. As the cumulative contribution of three factors from the first to the third factor, education, physical fitness and physique, was about 60%, these factors could be taken as major components contributing to assortative mating.

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Incidence data of thirty cranial nonmetric characters were presented for five Jomon population samples of West Japan as well as for protohistoric Kofun sample of west Japan and modern Kinki, Hokuriku, Okinawa-Amami, Sakhalin Ainu, and Korea-China samples, and data of 19 characters for Sakishima samples. COCHRAN'S tests show significant sex differences for 14 or at least 10 of 30 characters. Interpopulation comparisons were performed by applying metric multidimensional scaling analysis (MMDSA) to mean character differences based on side incidences of cranial nonmetric characters. Among the five Jomon populations, Tsukumo was most derived from other Jomon populations, that is Yoshiko, Inariyama, Hobi and Ota. As a whole, Jomon populations showed marked affinities to Hokkaido Ainu but not to any other population including Sakhalin Ainu or Kofun.

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Thirty-three mandibles were measured 3 times by each of 8 observers. Measurement errors in 10 mandibular measurement items were analyzed by nested analysis of variance, and the measurement items were classified into reliable and unreliable groups. To evaluate the loss of information caused by the exclusion of unreliable variables, a factor analysis was performed. The influence of the measurement errors on the results of an analysis of interpopulation relationships was investigated by cluster analyses of three kinds of biological distances using 40 Japanese groups (26 groups measured by the present authors and 14 groups by Commission of Anthopological Investigation of Modern Japanese Crania), and the magnitude of the geographic differences among Japanese mandibles was evaluated. Among the 10 mandibular measurement items, bicondylar breadth, mandibular length, condylar height, ramus breadth and minimum ramus breadth are reliable because they have small intra- and inter-observer variances. The results of cluster analyses indicate that the magnitude of the geographical differences among Japanese mandibles is greater than systematic inter-observer errors but smaller than sampling errors, and that the only significant difference in modern Japanese mandibles is that between the Ainu and the Japanese.

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In an attempt to evaluate biological affinities among South Pacific island people, SMITH'S Mean Measure of Divergence (MMD) statistic was applied to 24 non-metric cranial variants recorded on the samples of six Polynesian populations, namely, Mangaians in the southern Cook Islands, the outlier Polynesians of Taumako, Tongans on Tongatapu, and the North Island Maori, South Island Maori and Chatham Islands Moriori of the New Zealand group. In addition, those variants that were more variable or more differentiated among the populations sampled were selectively discussed in some detail. A cluster analysis of the MMD values between the study populations revealed that Mangaian's crania showed the closest affinity to Taumako outliers', and that they both were more similar in the incidences of such variants to the Tongan crania rather than to the New Zealand cranial series. The three New Zealand series combined to form another relatively tight cluster. Thus, a probability was suggested that early Mangaians and Taumako outliers biologically belonged to the western faction of Polynesians, which included the peoples of Tonga, Samoa and the nearby island groups. The antegonial notch was the most variable in frequency among the study populations of the 24 variants considered, followed by the palatine torus, the infraorbital suture, the mylohyoid bridging and the parietal notch in order.

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An adult male cranium of the Okhotsk cultural period was excavated at the Mena-shidomari site. Esashi-cho, Hokkaido, in 1987.
Only a half of the facial skeleton was preserved. The protruded glabella, low orbits, relatively small maxilla and zygomatic bones were the main anthropological features of this cranium, which resemble the features of the Hokkaido Ainu cranium.
The results of the craniometric deviation graphs and the PENROSE's shape distances also indicated that the Menashidomari cranium is closer to the Ainu than to the Okhotsk cranium.

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A new variant (designated AHSG 12) was encountered in two unrelated subjects in remaining Japanese orphans in China. Isoelectric focusing studies showed that it locates between AHSG 10 and AHSG 2 bands in the native serum samples, and it comes out on the cathodal side of AHSG 5 band in the desialyzed samples.

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Radiography is a very useful technique for anthropology in the fields of traditional morphology, functional morphology, biomechanics, and kinesiology. For a small-area radiograph (28×71cm at most) we can use easily medical radiography apparatuses supplied for general purposes. But in the case of a whole-body radiograph we must develop a special apparatus and work out a certain standardized method. The apparatus we have de veloped here makes it possible to take optimal whole-human-body radiographs in an upright position. Additionally, a perpendicular line going through the center of gravity of the body is superimposed in these radiographs. This line is very important for the functional analysis of the total skeletal system.

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