Local variations of the recent Ainu crania and their affinities to neighboring populations, both recent and prehistoric, were reanalyzed using multivariate statistical methods. Local variations in recent Ainu are apparent between the groups in northeastern and the other areas of Hokkaido. There is an evidence that the former group may have been influenced genetically to a certain extent by the Northeast Asian populations who adapted to xtremely cold climate. However, they still largely retain the characteristics derived from the indigenous populations in Hokkaido. It was reconfirmed that Ainu has, as a whole, descended directly from the prehistoric populations of the Jomon age through those of the epi-Jomon age in Hokkaido. Hypothesis of the Northeast Asian origin of Ainu that has been proposed by some geneticists is hardly acceptable from the morphological point of view. Discrepancies between morphological and genetic evidence should be examined thoroughly on the basis of more reliable data and methods.

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Human remains of the aeneolithic Yayoi period from the Shakameyama site in Ehime Prefecture, Taishaku-Nagoshi site in Hiroshima Prefecture, Karako-Kagi site in Nara Prefecture, Bishamon site in Kanagawa Prefecture, and Sano and Awajinsha sites in Chiba Prefecture were assessed as of the native or migrant type by using discriminant functions based on the tooth crown measurements. The Taishaku-Nagoshi, Karako-Kagi and two of three Bishamon remains were classified into the migrant type with high probabilities, while others were regarded as of the native type. From this finding, it is concluded that the genetic influence of migrants from the Asian Continent had at least expanded to the western part of the Kanto district by the middle phase of the Yayoi period.

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In order to understand the origins of Japanese people, this paper deals with the skull morphology of Late Pleistocene human fossils in Eastern Asia. After the Minatogawa 1 skull, the most complete Japanese Pleistocene fossil human skull now available, is described, a functional interpretation of the evidence is presented. The Minatogawa 1 skull exhibits many archaic features, which mainly relate to masticatory adaptation. When the Minatogawa 1 skull is compared with other fossil human skulls in East and Southeast Asia, it is found to exhibit morphological features slightly closer to the Wadjak 1 skull in Java than to the Zhoukoudian Upper Cave and Liujiang skulls in China. This suggests that there were no major human migrations between China and Japanese Islands in Late Pleistocene.

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A comparative study of skeletonized and wet specimens of a broad sampling of prosimian as well as anthropoid primates provides evidence for the first time of the diversity of morphology and articular relations of the carpals. Phylogenetically, it appears that derived states within Primates support the monophyly of a cheirogaleine-galagine-lorisine clade (marked contact between the os centrale and the hamate), an Old World monkey clade (lack of a hamate process), and a New World monkey clade (medially truncated, but mediolaterally oriented os centrale with a laterally elongate, horizontally oriented, distal extension that is overlapped extensively dorsally by the trapezoid, and broad contact between the lunate and capitate). The latter features provide the first definitive demonstration of New World monkey monophyly on the basis of easily recognized synapomorphy. Fusion of the os centrale and scaphoid seems to occur randomly among primates. This character is thus best interpreted as autapomorphic for the relevant taxa.

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Secular changes in dental disorders among three populations were compared. Material used comprised 829 Japanese dry skulls and 1089 living Japanese, 1160 Chinese skulls, and 1326 British and Scottish skulls. Prevalence of tooth-to-denture-base discrepancy (the discrepancy), the frequency of carious, and carious and missing teeth, as well as the mean score of tooth attrition were calculated. The discrepancy and carious teeth showed relatively steady progression in the Japanese group, the only exception being a high frequency of carious teeth in the Yayoi period. In the British material, the prevalence of the discrepancy and frequency of carious teeth showed an increasing trend but there were local variations. In the Chinese group, neither the discrepancy nor the dental caries seem to show any meaningful trend. There were significant correlations between discrepancy and tooth attrition in the Japanese, and between discrepancy and carious teeth in the British. The Chinese data did not show any significant correlations, possibly because their economy was multifarious from pastoral to stock farming. The main determinative factor of the discrepancy and dental caries seemed to be the influence of the primary economy of the groups.

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Cylindrically-shaped grooves that occur on the interproximal surface at or near the crown root (dentine-enamel) junction in human teeth are characterized by their shape, sharp margins, horizontal parallel striations, and shiny polishing. Ancient examples reported in the literature provide the oldest direct evidence of hominid tool use. Like other workers, we found these grooves in many populations of the Pacific Basin and adjoining continents. Of the various explanations for Interproximal grooves, the most reasonable one is they represent the habitual use of toothpicks. In our pooled sample the frequency per tooth for interproximal grooves is 0.78% (1, 199/154, 167 teeth). The frequency of individuals with one or more interproximal grooves is 3.5%. Oceania has the greatest number of individuals with interproximal grooves (8.9%). Most of these crania originated in Australia. The American Arctic sample has no individuals with interproximal grooves, and prehistoric Arctic teeth lack crown caries. Elsewhere, frequencies of interproximal grooving vary markedly within and between regions suggesting multiple causes. Interproximal grooves are the result of habitual back-and-forth rubbing with a toothpick or some other artifact. In some cases rubbing may have started in an effort to deaden or desensitize a carious or inflammed site. Whatever the original stimulus, groove depth varies with individual age, indicating many years of habitual rubbing.

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In measuring basal crown and cusp areas of molars, one must determine a standard reference plane on which the projected measurements are made. In this paper, we present a new three-dimensionally based system which enables an objective determination of crown orientation. This is done by combining five laser scanned images of a molar taken occlusally and from four oblique angles to form a composite three-dimensional representation of the entire molar crown surface. Using this digitized data set, we derive a standard occlusal orientation that maximizes projected occlusal surface area. We can also choose other orientations for projection, such as those defined by the cervical line or cusp apices. Crown and cusp areas were measured in each of these orientations and compared for discrepancies on a mandibular first molar of Australopithecus afarensis. We found that orientations differ by more than 10 degrees, resulting in large discrepancies in cusp area values. It is concluded that, to enable reliable interpretation of cusp area data, whatever orientation methods used should be carefully chosen and rigidly followed.

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The purposes of this study are to compare the characteristics of mandibular internal structures between Neolithic Jomon and modern Japanese, and to investigate the relationship between internal structures of the mandible and the standing position of the teeth in both populations with the use of CT scanning. The data for this study were obtained from 40 male Japanese and 39 male Jomon dry adult skulls housed in the Department of Anthropology and Prehistory, the University Museum of the University of Tokyo. For each specimen, a lateral radiograph of the skull and four CT scan sections of the mandibular body were available.
The lingual inclination of mandibular molars of Jomon was weaker than that of modern Japanese, and mandibular cortical bone of Jomon was thicker than that of modern Japanese mainly because Jomon had strong masticatory function. Although the dental arch breadth of Jomon was larger than that of modern Japanese, there was no significant difference in the mandibular body breadth in molar regions. It was suggested that overall size of mandibular body of Jomon was almost the same as that of modern Japanese, but the larger dental arch breadth resulted from upright position of molars.

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The relative size of the cusps of the first mandibular molars of extant great apes and the Miocene hominoids, Proconsul and Sivapithecus were compared. As previously shown, molar morphology can differ between populations of the same species. Although the differences in crown size and shape are not as great as expected, each extant great ape species has a different overall design of the cusp base, probably reflecting its evolutionary history. The relative sizes of the cusps in Proconsul and Sivapithecus are different from those of any extant great apes.

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Seven indicators of stress (cribra orbitalia, osteoarthritis of apophyseal joints in the cervical vertebrae, spondylosis deformans in the lumbar vertebrae, spondylolysis in the fourth or fifth lumbar vertebrae, osteoarthritis of elbow and knee joints, and inflammatory changes of bone) were examined in human skeletal remains from eight prehistoric Jomon sites in Japan. Among these indicators, spondylosis deformans in the lumbar vertebrae showed the highest frequency of occurrence, and rose with increase of age. On the other hand, osteoarthritis of apophyseal joints in the cervical vertebrae showed the lowest frequency of occurrence, which means that the Jomon people might have a lifestyle or behavior which overloaded the lumbar more than in the cervical vertebrae. There were no significant differences of frequency of occurrence of each indicator among the major Jomon sites examined in this study. However, two skeletal series from the shell mounds in the Atsumi Peninsula in Aichi Prefecture showed relatively higher frequencies of occurrence of osteoarthritic changes in both elbow and knee joints.

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The measurement error for femoral oblique and total tibial length was examined based on data of the author and of Nishi (1928), using modern Japanese samples and Martin's method. Intra- and inter-observer measurement error was quite small for the femoral oblique length and the difference between the two variances was not significant in an F-test. Oblique length data in the literature may thus be considered reasonably accurate. For the total tibial length, inter-observer error was greater than intra-observer error and the difference between the two variances was significant in the F-test. Total tibial length may differ slightly between measurement values for the same sample obtained by different observers.

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The metric data of the neurocranium and the sacrum from 30 male and 20 female Japanese were examined through multivariate analyses. In result, significant associations were found between cranial length and the sacral breadths at the upper and middle levels both in males and in females. From these findings and previous studies, it is inferable that the form of the maternal pelvic inlet has been and is still one of the most important determinants for the neurocranial form in modern human populations, and that the close correspondency in form between the neurocranium and the pelvis is now fixed as a population character.

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Foot dimensions, indices, and variables relating to shape characteristics of foot outlines taken for Japanese, Australian aborigines, Indonesians and French were analyzed and compared with existing data to identify the differences due to growth, generation and ethnic background. The following findings were obtained: 1) There has been rapid increases in foot length for Japanese born after ca. 1950. 2) Japanese born after ca. 1960 had a smaller foot girth and foot breadth for their foot length compared to Japanese born before ca. 1950. 3) Secular change rather than aging is responsible for the generation differences in foot size and proportion. 4) Elderly female Japanese born before 1930 had very wide feet and a weaker valgus tendency of the first toe. Special attention should be paid to the needs of older men, and especially older women in the production planning and designing of the toe shapes of shoe lasts. 5) Differences due to growth and secular change in foot outflare, which is represented by posterior flexion angle of the medial axis of foot outline, were not significant. Ethnic differences in foot outflare was not significant for females. This does not appear to be easily influenced by environmental factors, such as nutritional status and shoe-wearing habits. 6) Mongoloid populations including Japanese have a wider foot for foot length compared to Caucasoid and Australoid populations. 7) East Asian populations including Japanese have a smaller foot length for height compared to Southeast Asians and Africans. The causes may be both genetic and environmental.

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Somatometric research was carried out in Lima, Peru, in 1995. Twenty one body measurements, 15 cephalic measurements and an outline of the right foot were taken. The number of people measured were 107, 41 men and 66 women. Subjects were chosen through a screening process based on their birthplace and the birthplace of their parents. The number of selected subjects were 74 (33 men and 41 women). Their somatometric data was compared with that of Okinawans born during the same period, younger Japanese (19-29yrs) and older Japanese (the same age as the Lima Nisei subjects). The body type of Lima Nisei is close to that of older Japanese in their height but larger in their breadth and circumference. Head measurements show that the Lima Nisei have still their original morphology of the Okinawans. Their changes are supposed to be modernizing alteration of the body. The European or American lifestyle and nutrition in Peru are considered the main reasons these changes have occurred.

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