In this review, the characteristics of human walking were discussed with special reference to step length, cadence, speed and energy expenditure. For this purpose, the natural walking was distinguished from experimental walking including floor and treadmill walking in a laboratory. The conclusions obtained from this review were as follows.
1) Step lengths in natural and floor walking tend to be greater compared with those obtained during treadmill walking.
2) The older people walk with shorter step length, slower cadence, longer walking cycle and slower speed as compared with the younger people.
3) The sex differences which were consistently found both in natural and experimental walking were higher speed walking with longer step length in men than in women.
4) There exist the regional difference in walk-ing speed and the ethnical difference in gait pattern. In Japan, the people in Osaka and Tokyo seem to walk faster than those in other cities investigated.
5) In natural walking, Japanese walk with shorter step length, higher cadence and faster speed than American. In treadmill walking, the step length of Japanese was shorter than Caucasian by about 5cm at any speed.
6) The degree of shoulder extension increases with the walking speed. At the speeds of 120 and 130m/min, the tall subjects showed the least excursion of shoulder extension.
7) For the prediction of the metabolic costs during experimental walking, an equation was presented from the literature (PANDOLF et al., 1977) which took account of body weight, external load carried, walking speed, nature of terrain and grade.
8) It is estimated that the energy cost of overcoming wind resistance in walking is about 10% of total energy cost at the wind velocity of 5m/sec and 35% at 8m/sec.

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φInterobserver errors in scoring presence or absence were investigated for 31 nonmetric cranial traits based on a sample of 203 almost complete Polynesian skulls using the correlation coefficients of attributes. The φ coefficients for all 31 traits were statistically significant at the 0.01 level. When the φ value of +0.7 was regarded as the critical point for assessing interobserver replicability, 20 traits were selected. Since the MMD on these 20 traits did not reach the significant level of 0.05, these traits were considered to be reliable for comparisons between different observers. Because interobserver error was larger than intraobserver error and some anthropologically important traits did not clear the threshold for assessing consistency, it is recommended that physical anthropologists should investigate nonmetric cranial traits by themselves.

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Eight species of macaques are compared according to the partitions observed in four kinds of cranial nerve perforations: hypoglossal canal, infraorbital foramen, stylomastoid foramen and mental foramen. Chi-square tests using 256 Japanese macaque crania showed virtual absence of a significant influence of age, sex and side factors on the cranial nerve perforations, which permits the maximization of sample sizes. Cluster analysis of a correlation matrix among right and left sides of the four characters and sex and age factors reveals that the characters segregate into "gnathic" and "basicranial" clusters and that sex and age factors join with "gnathic" cluster before the final overall connection. It is, however, concluded that the partitions of the cranial nerve perforations in macaques are virtually independent of age, sex and side factors and that intercharacter correlations among the four kinds of cranial nerve foramina are generally low except for the bilateral correlations.
Though the overall pattern of the interspecific comparison through cluster analyses is not stable across the distance measures and clustering procedures applied, the derived positions of Macaca fascicularis among the four species of the fascicularis group and M. nemestrina among the eight species compared are repeatedly obtained. This interspecific pattern is also confirmed by principal component analysis.

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This paper is concerned with the problem of the origin and the racial affiliation of recent Sakhalin Ainu, rather than with the well-known uniqueness of the cranial morphology of this population. In this study, odontometric and morphological observations were performed on the dentition of Sakhalin Ainu.
The overall tooth size of Sakhalin Ainu is quite small. In this respect, Sakhalin Ainu shares the similar characteristics with those of Hokkaido Ainu, the Neolithic Jomon population, some geographically isolated Japanese, and Negritos. As regards the shape factor of the dental measurements, on the other hand, Sakhalin Ainu shows the close affiliation to the typical Mongoloid populations such as Aleuts, Karluk (Alaska Eskimos), Chinese from the northern area of China and modern main island Japanese. Distance analysis based on the several non-metric crown features displays the intimate association of Sakhalin Ainu with Negritos and the populations who may have been derived directly from Southeast Asian Proto-Mongoloid population.
Taking these results into account, we cannot ignore some genetic influence of Northeast Asian populations on the physical characteristics of Sakhalin Ainu. However, the origin of this population may have been traced back to the Southeast Asian Proto-Mongoloid population. The dental evidence shown in this study may contribute to the establishment of biological relationships among Sakhalin Ainu and the neighboring populations.

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Metrical and nonmetrical crown characteristics in the permanent dentition were investigated for seven protohistoric Kofun population samples from western and eastern Japan. The difference between the western and eastern Kofun series was significant in only one measurement in males, whereas in five measurements in females. The metrical analysis of female dentition indicated that the Kofun series of eastern Japan had a slight resemblance to the prehistoric Jomon series which were characterized by smaller overall crown size. However the overall crown sizes of the other Kofun series were larger than those of the Jomon and recent series of Japan. From these results, it was inferred that the Kofun series were closely tied to the Aeneolithic Yayoi series of immigrant type characterized by larger overall crown size, and that the genetic influence of the immigrants in eastern Japan was greater on males than on females during the Kofun period. On the other hand, the nonmetrical data showed close affinities between the recent Japanese series and both the Kofun series of western and eastern Japan, with a large gap between the Kofun and Jomon series. These results suggested that the distribution pattern of nonmetrical crown characteristics of the recent Japanese series had been constructed, at the latest, by the end of the Kofun period.

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Effects of erect bipedal standing exercise on the skeletal morphology were investigated in seventeen growing male rats divided into control and exercise group. Using the newly devised 'bipedal training box', in which rats achieved a fully upright stance through positively reinforced operant conditioning, the exercise group was burdened with the bipedal standing exercise from 64 days to 140 days of age, totally in 136-138 sessions. At the age of 140 days, the left femur was dissected out, ten serial cross sections of the femoral diaphysis were cut from proximal to distal and cross-sectional properties were calculated from the photographs of the sections. The bipedal standing exercise had the following effects on the femoral diaphysis; an increase in the cross-sectional area, area moments of inertia in the proximal half of the shaft, i.e. the strength of the femoral diaphysis increased against axial compressive, antero-posterior bending and medio-lateral bending, respectively; an increase in the polar moment of inertia and an external rotation of the principal axis in the vicinity of mid-shaft, i.e. the strength against the torsional load increased and the direction to resist the maximum bending load more or less approached the antero-posterior direction. These observations were discussed in comparison with the effects of quadrupedal running exercise on the femoral cross section previously observed by us.

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We extracted the DNA from the Jomon skeletal remains and amplified a part of mitochondrial DNA sequences by using the polymerase chain reaction method. The methodology concerning the extraction, purification and PCR amplification of ancient DNA from the skeletal remains were assessed critically for further application.
The materials used were three skeletal remains iscovered in Chiba Prefecture, that is femur (Imaizumi 1), skull (Imaizumi 2) and tibia (Kusakari). Chronologically, Imaizumi site bel- ongs to the middle phase of Jomon Period and Kusakari Shellmound belongs to the late phase of Jomon period.
Southern hybridization analysis with human Alu repetitive sequences probe revealed that the purified sample from ancient skeletal remains contained very little amount of human DNA and most of the DNA recovered might be of the bacterial or fungal origin.
Amplified mitochondrial DNA sequences by PCR method were V and D-loop regions both containing noncoding sequences that are known to have intraspecific sequence heterogeneity.
Although there was no Hae III restriction polymorphism in PCR amplified region V sequence, nucleotide sequence analysis revealed single substitution T at 8240 to A in one indi- vidual. As for D-loop region, we could not find restriction fragment polymorphism expected by Ava II, Hpa II, Hae III digestion, including three samples from contemporary human. Nucleotide sequence analysis might be needed in this region.
The study of ancient DNA seems to have a number of technical difficulties, but the method described in this article gives considerably stable result for extraction of DNA from human skeletal remains. In conjunction with this method, we used polymerase chain reaction, in which short region of particular gene can be greatly amplified specifically in vitro from extremely small number of DNA molecules. It makes possible to amplify the ancient DNA up to the amount which allows us to apply standard laboratory techniques for further molecular analysis.
More extended work involving numerous individuals from ancient human skeletal remains will bring the valuable information to the field of anthropology.

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The origin of the ritual tooth ablation of Doigahama Yayoi people has been long discussed since this problem is concerned with the question of the Yayoi people's origin in Northern Kyushu and Yamaguchi Prefecture. No definite answer, however, has yet been obtained, partially because of a deficiency in the data on ritual tooth ablation of this site.
One hundred and seven skulls, excavated from the Doigahama site during the 1st to 11th surveys, are examined here and compared with late Jomon and other Yayoi peoples. In Doigahama, the intentional extraction of one or more front teeth was found in 81 skulls (75.7%) which is a relatively high frequency among the Yayoi population, though it is lower than that of the Tsugumo, Yoshigo and Inariyama sites in the late Jomon period (nearly 100%, Table 2). There was also a sex difference observed for this frequency in Doigahama (male-64.2%, female-87.5%, Table 3).
Ritual tooth ablation found in Doigahama is characterized by the following points;
1. The main object of tooth extraction is canine, especially the upper canine, and about 80% of individuals have the traits of this practice. In this regard, there is a possibility that the Doigahama people engaged in the same tradition of the Jomon people, but the number of extracted canines in Doigahama, as well as the other Yayoi people, decreased to half or one-third of that in the Jomon people (Table 6). Furthermore, the canines of males were extracted unilaterally (right side in almost cases) and those of females were extracted bilaterally.
2. The upper lateral incisors were also frequently extracted (54%). The Yayoi peoples of Doigahama and Northern Kyushu are distinguished from Jomon and North-west Kyushu Yayoi in respect of the frequency of this type of tooth ablation (Table 8, Fig. 3).
3. Lower front teeth are seldom extracted in Doigahama and it provides an excellent comparison with the Jomon and North-west Yayoi people, which is characterized by a high frequency of extraction in the mandibular front teeth. The typical type of ablation of the Jomon people, in which all incisors in the mandible are extracted, does not exist in Doigahama. Sex difference was also observed in the frequency of lower tooth extraction among Yayoi people, especially in the North-west Yayoi people.
4. The ritual ablation practices of Doigahama were begun at 12-13 years of age (Table 9, Fig. 5).
As a whole, ritual tooth ablation in Doigahama shows a distinct difference as compared with that of the Jomon peoples, though some similarities were also revealed. The Yayoi people in north Kyushu show resemblances to the Doigahama in these points. On the other hand, the rituals of north-west Kyushu bear a certain similarity to the Jomon in their practice of teeth removal. Furthermore, the ancient Chinese may have something in common with the Doigahama, the practice in which are characterized by extraction with a strong bias for upper lateral incisors and by ascarcity of tooth extraction in the mandible.
According to these results, it would be unsuitable to say that the Yayoi people in Doigahama carried on the same tradition of ritual tooth ablation as the Jomon people, and the influence of other migrant populations from the Asian Continent would be a subject eminently worthy of further consideration.

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The rare properdin factor B variant type (BF SO45) was first detected in the Japanese population using high voltage agarose gel electrophoresis and immuno-fixation. The propositus was a 75-year-old man living in Yamanashi Prefecture. The family study confirmed the genetic transmission of the BF*SO45 allele. BF*SO45 is the fifth rare BF variant allele found in Japanese.

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A new simulation model has been constructed to estimate demographic processes of prehistoric human populations who migrated and dispersed, particularly to uninhabited habitats; this model simultaneously treats fertility, mortality, and migration, taking the carrying capacity of the land into account. Our preliminary trials have produced satisfactory results. The applicability of this model to historical reconstructions is also discussed.

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