Tooth to denture base discrepancy is a concept which has been developed by orthodontists as their diagnostic measure for the decision of permanent tooth extraction for orthodontic treatment. It is now coming to be considered as one of the major etiologic factors, not only in malocclusion, but in dental caries, periodontal disease, pericoronitis, tooth impaction, dentigerous cyst, and so on.
In the present paper, these instances were shown (Figures 1-3), and the nature and origin of this unfavorable phenomenon were discussed from the stand point of human evolution and civilization.
The author's conclusive opinion may be summarized as follows: Under the close effect of civilization, especially of the eating behavior, diminution of the facial bones and the tooth has consistently taken place through the course of human evolution. However, the rate of reduction was higher in bones which is more labile to the circumferential functional stimuli, while the tooth has been more stable because the tooth crown does not have any remodeling process after the completion of its formation. Thus the disharmonious diminution of these two components of occlusion, being accompanied with the acceleration through the selection by favorable facial esthetics directed to the orthognathism, has resulted in the discrepancy.
Considering the rather rapid increase of malocclusion, dental caries, and other related disorders in the present era, even collapse of human occlusion might be expected in relatively near future, if a catastrophic rush occured in further development of the discrepancy.
The present study on the discrepancy problem has brought to the author the poignant realization that the interdisciplinal communication between anthropology and dentistry is really worthwhile, and even requisite for further advance in both of these fields.

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The antero-posterior inclination of the Frankfort horizontal was investigated in 21 male and 21 female young adult Japanese, holding their heads in the natural head position during horizontal gaze. Horizontal gaze was attained either by simply looking straight forward or by looking at one's own eyes in a vertically placed mirror. This was carried out in sitting and standing positions. For each subject, more than 21 observations were recorded in each of the positions. The distribution of the multiple observations showed no significant departure from normality and the natural head position was found to be reproducible within limits of ±3.4° to ±3.6°. Thus, the validity of the natural head position concept was confirmed.
In Japanese, the Frankfort horizontal was found to possess a slight anterosuperior inclination, as opposed to an antero-inferior inclination reported for American and European whites. It is discussed that this difference may amount to 5° to 10°, thus indicating that the Frankfort horizontal does not have the same somatological meaning in Japanese and American or European whites.

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Though the total energy metabolic rate during exercise was three times of that duringrest, the sum of energy metabolic rates of internal organs during exercise was as same as that during rest (see Table 1; LEHMANN, 1953).
JANSKÝ (1964) pointed out that when the maximal metabolic rate occured in human body assame as many other mammals the total energy metabolic rate ncreased to about ten times of basal metaboric rate (BMR). It was achieved mainly by muscle and the sum of metabolic rates except that of muscle increased to only two times of that during BMR at most. Therefore selecting different items of exercise in which the total energy metabolic rates are similar, we can assume that the sum of energy metabolic rate other than that of muscle is constant. And under the condition that metabolic changes are restricted to n muscle groups, we can express the total energy metabolic rate during i-th exercise Hi as follows.Hij=nΣnj=1Mij+B₁ (1)Where mij: energy metabolic rate in j-th muscle at i-th exercise [Kcal/h] ; B1: energy metabolic rate in organs other than n muscle groups [Kcal/h].
It is difficult to measure mij directly but mij can be decided by using a indicator fij, which is in linear proportion to mij.mij=cjfij (2)where cj is the coefficient, of which value is dependent on a kind of muscle in individuals.Hi=nΣj-1cjfij+B₁ (1)'
Selecting κ different exercises in which the total energy metabolic rates are similar and equation (2) can be consisted among active muscles, we can obtain the following equation (3).Solving equation (3) for c₁-c_n, we can get each local muscle energy metabolic rate by use of equation (2).
The possibility that the integrated surface EMG mij was applied to a linear indicator of mij was described. In isometric sustained muscle contractions, the relationship between mij and mij can be expressed as the following equation, which is exactly the same as equation (2).Mij=cjmij (6)And it was pointed out that equation (6) was adopted under some kinds of dynamic muscle contraction. In the other muscle contracting type, it was necessary to confirm equation (6) at first in order to use the present prediction method. The validity of equation (1) and (3)was discussed concentrating on an accuracy of prediction. A few formation methods of equation (3) for solving c1-cn were explained concerning with a real experimental situation.The effect of muscle fatigue and thermal environmental factor on equation (6) was discussed, too. It was emphasized that the data during muscle fatigue and in an extreme thermal condition especially a cold stress should be avoided.
An applied example was given to clarify the present prediction method of local muscle metabolic rate.

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The well known cline in ABO blood group gene frequencies in Japan was analysed based on the working hypothesis of a transient cline formed by the admixture of two heterogeneous populations by diffusion.Mathematically, the model corresponds to solving the diffusion equation with a step function as the initial condition. Using the A allele frequency data, the position of the initial discontinuity in the gene frequency is estimated by simulation as having been in the vicinity of present day Gifu City, and again assuming 20 km per generation of 25 years for a standard deviation of migratory distance the time as approximately 2, 000 years since the commencement of admixture. This and other results of simulation were discussed in the light of possible population movements induced by rice crop farming during the Yayoi era in western Japan.

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In the previous paper 20 measurement items were selected on the basis of principal component analysis and cluster analysis of 44 somatic measurements taken from 112 young adult males for the purpose of obtaining an objective selection of somatometric measurement items (KOUCHI, 1979).In this paper, two analyses were carried out using Pearson's product moment and Spearman's rank correlation coefficients for the purpose of establishing the validity of this selection. First, the accordance between the matrices of inter-subject similarity coefficients obtained from the original set and from the selected set of measurements was examined using mean square distances, Penrose's size and shape distances and Q-mode correlation coefficients.Secondly, the accordance between the scores of six interpretable principal components obtained from the original set (O-scores) and from the selected set of measurements (S-scores) was examined.
The results show that: 1) the informations contained in the original set as a whole is well represented by the selected set; 2) O-scores are satisfactorily represented by S-scores in six of the seven aspects. It is concluded that the validity of the selection is established because the informationscarried by the selected measurements satisfactorily represents the whole as well as six relatively independent aspects of the informations carried by the original set of measurements, and that S-scores may be used instead of O-scores as a convenient indicator.

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A new system named the polynomial equation method was proposed in the present study for the determinations of the lower and upper critical air and body temperatures for oxygen intake at rest. Nine young adult males were tested by the new method and the critical temperatures of them were determined as follows: the lower critical air temperature to be 23.8°C, the upper critical air temperature to be 45.4°C, the lower and upper critical mean skin temperatures to be 30.0°C and 35.9°C, and the lower and upper critical rectal temperatures to be 35.5°C and 37.9°C respectively.

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