Polymorphisms of HLA-A, and -B antigens were investigated in the Kyrgyz population living in the northeastern part of Central Asia. Serological typing for HLA-A and -B loci was performed in 157 healthy unrelated blood donors. The frequent HLA-A antigens were A2 (29.2%), A24 (20.6%), and A1 (10.4%). For HLA-B loci, B51 (10.6%), B17 (9.1%), B13 (8.7%), and B35 (8.5%) were predominant. Multidimensional scaling and phylogenetic analysis were performed based on the gene frequencies of HLA-A and -B. In the multidimensional scaling for 24 worldwide populations, Kyrgyz situated itself close to other Central Asian populations. In the phylogenetic tree, Kyrgyz were included in the cluster of Central Asian, while they located close to the European cluster. Four HLA-A-B haplotypes, A2-B blank (5.7%), A2-B13 (4.7%), A24-B51 (3.9%), and A2-B17 (3.7%) were observed at frequencies of more than 3%. These haplotypes, except for A2-B blank have been observed in European and/or Asian populations. The present results well agree with the hypothesis, which has been proposed in morphological studies, that Kyrgyz have been derived from not only Mongoloid but also Caucasoid ancestors.

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Prehistoric Japanese population is believed to have increased from 75, 800 in 300 B.C. to 5, 399, 800 in A.D. 700-a 70-fold increase in 1, 000 years. The rate of natural increase-hereafter called the annual growth rate-likely averaged 0.1% during this period. A closed population growing at this rate would have experienced only a 2.7-fold increase, so that the deficit must have been balanced by immigration, and the question is how much? Hanihara (1987), who assumed constant growth and immigration rates, arrived at an estimate of over 3, 000 immigrants per year-an “unacceptably” high level of immigration. In this paper, we modify Hanihara's original model to permit the annual growth rate to vary around the long term average of 0.1%. Specifically, we model the annual growth rate as an autoregressive time-series with normally distributed random shocks. When the autoregressive coefficient, b, and the standard deviation of the random shocks, h, are large, the requisite level of immigration may be substantially reduced. In particular, with b=0.9 and h=0.1, 50 immigrants per year may suffice. Time-series data on crude birth and death rates are available from historical-demographic studies. Unfortunately, the parameters b and h estimated from these data may not be large enough for the predicted reductions to occur.

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A well-developed basal tubercle was found in the lingual surface of the upper central incisor in the Cook Islanders. The basal tubercle was accompanied with large spines, and limited to the central incisor. Such a configuration was thought to be almost the same characteristic as the “tubercle-shaped” incisor observed in Homo erectus, Peking man in China (Adloff, 1938). Females exceeded males in frequency of the basal tubercle. This characteristic was associated significantly with the spine (P<0.01), but not significantly with shovelling. Although the tooth size of the central incisor with a pronounced tubercle tended to be larger than that without the tubercle, the difference was not significant.

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In order to clarify quantitatively the changesin foot shape caused by wearing heeled shoes, the three-dimensional shape of the right foot was measured for 39 female subjects under the following three conditions: 1) standing on a horizontal plane, 2) standing on a base with a surface simulating a shoe with a heel height of 4cm, and 3) standing on a base with a surface simulating a shoe with a heel height of 8cm. The shapes of the foot measured under the different conditions were compared using the shape characteristics of foot cross sections and foot outlines in addition to foot dimensions. Sixteen cross sections were calculated perpendicular to a reference plane defined by metatarsale tibiale, the medial heel point, and the foot axis. The shape characteristics used were a flatness index, the direction of the major principal axis, the maximum height and the maximum breadth for sections which were located between MT and the junction of the foot and leg and have closed outlines, the inclination of the midline for sections which were located around the medial and later malleoli, as well as the overhang of the navicular bone and the posterior flexion angle of the medial axis for the foot outlines. As the height of the shoe's heel increased, the medial and lateral arch lengths and the foot breadth became shorter; sections 1-8 became higher, narrower, rounder, and rotated anti-clockwise in the anterior view; the medial inclination of the heel weakened; the foot outline became less outflared and the overhang of navicular bone became less conspicuous. These changes are related to the supination of the foot. Variations in these characteristics did not diminish in conditions 2 or 3, and individuality remained despite these changes. The relation between the changes in these shape characteristics and the height of the heel was not linear. The possible causes of these changes and their significance for designing shoe lasts are discussed.

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Bony bridging of the mylohyoid groove of the mandible (mylohyoid bridging) is one of the minor cranial variants and its frequencies in human groups have been used for population studies. Its value as a genetic marker, however, has not yet been established. Formalin-fixed human lower jaws of 16 individuals and human mandibles of 2, 158 individuals were morphologically and statistically examined. The findings indicate that the two basic types of mylohyoid bridging, lingular type and bridge type, can be treated as one and the same trait. Bilaterality in the expression and the occurrence independent of age and sex are consistent with the assumption that genetic background is relevant to its formation. Moreover, relationships of human groups based on the frequency of mylohyoid bridging are compatible with those based on dental morphology and human genetic analysis. Although the mylohyoid bridging occurs with high frequency in Neanderthals, it can also be observed in European Upper Palaeolithic humans with distinctly higher frequency than in subsequent populations. This finding appears to be important in arguments regarding the population history in Europe, if genetic background is relevant to the expression of mylohyoid bridging as assumed from the present study.

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It is generally perceived among anthropologists that the degree of tooth wear had been consistently heavy in our ancestors until several thousand years ago. In order to test this impression quantitatively, degree of occlusal wear was compared among several fossil and subfossil groups of our genus, Homo, using a wear scoring method based on an ordinal scale. In spite of several restrictions in the nature of the available samples, the results support the view that heavy occlusal wear such that make the whole occlusal surface completely flat had been ubiquitous and normal in the course of past two million years of human evolution. This observation is important because it constitutes the fundamental premise of Begg's hypothesis that the human dentition and occlusion are adapted to heavy tooth wear.

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The alveolar profile angle has been measured on skulls of prehistoric and historic populations of Japan by several authors. However, there is still a veil on the trend of the change of this angle specially in the modern times.
The present study approaches this problem by using a X-ray lateral cephalometric technique with the skeletal materials of at least 40 individuals from each period (a total of 470 individuals from 7 periods: Jomon, Yayoi, Kofun, Medieval, Edo, Modern I, and Modern II). Temporal changes of alveolar profile angle and correlations of this angle with other measurements were examined using cephalograms of these skeletal materials. This angle had high within-group correlations with facial height and the inclination of the upper central incisor to the Frankfurt horizontal. An individual having a large profile angle had an up-right position of the upper incisor. The angle being the largest in Jomon people was gradually reduced in the Medieval to Edo period before increasing again up to the present time. Although the inclination of the incisor showed a parallel relationship with the alveolar profile angle up to the Edo period, it did not show a clear increase in modern times. It was concluded that these two angles had a close association in an individual level of a single population. The cause of these changes in craniofacial morphology, especially in Medieval and Edo periods, might not be simple, but this characteristic should be considered along with other physical characteristics such as stature, alveolar prognathism, tooth size, and dental disorders which were previously reported as showing similar trends of temporal changes in Japan. The present study basically support previous studies, but it showed that samples after World War II represented a catch up of this angle, and that some highly correlated items in cranial measurements with this angle such as facial height and incisor inclination were found in almost all the samples in 7 periods.

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