Aogashima is a very rocky and steep-sided volcanic island, situated in the ocean to the south of Tokyo, and almost isolated geographically and culturally because of its relative inaccessibility.
We examined the physical capacity of 148 male and female islanders over the age of twenty years, for back muscle strength (1), grip strength (2), static balancing (3), match board test (4), tapping (5), reaction time (6), and closing-one-eye test (7) (refer to KoHARA's report, J. Anthr. Soc. Nippon, Vol. 63, No. 4).
Except for the match board test, the males surpassed the females in all tests especially in those concerned with muscular strength (1, 2 ). A very striking decline was noted in each test with advancing age, especially in those tests requiring muscular strength, or in those relating to movements of the entire body (1, 2, 3), and on the other hand, there was relatively little decline in manual movements (4, 5, 6). Such results agree with the general fact that the aged become unable to perform whole body movements, but display often considerable efficiency in manual activity. Reaction time tests indicate clearly a loss of agility in the older people, although marked individual differences were noted. The fact that a trend tword decline in the closing-one-eye test (7) appears with advancing age, can not be explained.
One of the cultural features of this island is for the older people to engage in more or less heavy works. Such a phenomenon seems to be due to the weakness of family-ties in this society, which require individualistic subsistence for aged people.

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Aogashima Island lies in the Pacific Ocean about 360kms. distant from Tokyo. The author studied the teeth of 264 inhabitants, 133 males and 131 females, ranging from 1 to 80 years of age. The methods used were direct oral examination and plaster-modellig of the jaws by use of the so-called alginate impression materials.
The results are as follows :
(1) Dental caries are rare, the percentage of caries in the permanent teeth being 4.63 and in the deciduous teeth 14.0. (2) The deciduous teeth most frequently suffer from caries in degree C1 followed by C2 and C3. The permanent teeth suffer most frequently in degree C3 followed by C2 and C1. (3) The occurence of pyorrohea alveolaris is very frequent not only among the aged but also among the young. Its percentage is 54.8 in adults of more than 21 years of age. (4) Pyorroea alveolaris and dental caries occur more frequently among females than among males. (5) Malarrangement and the malocclusion of the teeth are rare. (6) No occurences of the so-called motteled teeth were recorded. The drinking water contains no marked amount of fluolin or other decay-preventive materials for the teeth.
The dental diseases among inhabitants seem to be chiefly caused by the composition of the food and other environmental factors on the island.

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Aogashima island lying about 360kms. southward from Tokyo, is considerably separated from the Japanese mainland. Its inhabitants, mostly poor farmers, number 388 and the number of households is 104. The average number of members per farmer household is four, while in the rural districts of Japan it is six. This smallness of family size resultes from the customs relating to retirement of this island community.
From the standpoint of the family cycle, I divided all couples, widowers and widows into six stages : (I) the first stage, to which belong families having as yet no children, (II) the second stage, to which belong child-rearing families, (III) the third stage, to which belong families which are also rearing young children, but with part of the children emigrated, (IV). the fouth stage, to which belong couples who have unmarried children, under their care, and married sons or daughters on the island, (V) the fifth stage, to which belong couples who have only married children, (VI) the sixth stage, to which belong widowers and widows having no children. The number of the first stage couples is 21, that of the second is 32, that of the third stage is 9, that of the fourth stage is 12, that of the fifth stage is 25, and that of the sixth stage is 12.
One of the remarkable problems of population adjustment in the very low economic level of this island is that many old couples, old widowers and windows live in retirement and can get little support from their own adult sons and daughters. These poor old men and women maintain psychologically a mental state of ease in their retired life, but economically are compelled to live out the final course of their lives under miserable conditions.

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Aogashima island is a small volcanic island situated in the Pacific about 360 kilometres south of Tokyo. In November 1954 an anthropological survey was caned out on this island. As a result of anthropometrical measurements of 70' native adults, 40 males and 30 females, some bodily traits were revealed to be rather characteristic of Aogashima islanders. In the first place stature was so markedly short in both sexes as scarcely to be met with among the means for stature of any other local groups in Japan. The mean measurements for biacromial breadth, chest girth and head length were fairly large, and the lower limb length was relatively short. The acromion height was less than the suprasternal height against the fact that among the Japanese as a whole the former is generally larger than the latter. The result of measurements of 96 younger people from 3 to 19 years of age showed that they also possessed body traits similar to those of the adults. Low stature and other traits are presumably to some extent due to inbreeding which seems to have been more frequent in the past than at present. The rate of breeding among the present inhabitans is not so markedly high in comparison. with those in other parts of Japan. Besides hereditary factors, the types and chemical constituency of the food and the labour conditions on the island are considered to be important factors causing the characteristic bodily traits of the inhabitants. From the nutritional point of view the food of the inhabitants seems to be notably unbalanced so far as the necessary nutriments are concerned. The staple food is. the sweet potato which is cultivated on the island while green vegetables are rarely used as daily food stuffs. The steep coastal cliffs prevent the peoples from fishing and food aversion to eating animal meats and milk is rather common. In daily life the peoples are obliged to walk up and down steep slopes wherever they go on the island, since the island is formed of a double volcano, the people having their villages on the outside slope of crater with their fields in the low calderaa basin which it surrounds. Even small children have to be engaged in fairly heavy work to assist the labour of the adults.
As to the physical growth of school children on the island, the body size of children at each age level has become progressively larger during the last seven years. This is similar to the general trend noted in other parts of Japan where the conditions of life have become more favourable in promoting the growth of the body year by year after the War.

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