There exists so far no definite explanation of the racial differences in the age of puberty. Reche says, "It is conceivable that the characteristically late maturity of a tropical race (like that of the Melanesians) may gradually have been acquired by the unfavourable influence of too hot a climate or of continual underfeeding acting on many generations."
It is remarkable that, in contradistinction to the Melanesians, the Indians become mature very early, and the same applies most likely to the Australians. In India, as in Australia, sexual intercourse is begun at a very youthful age, among the girls often long before the first menstruation. It is possible that on account of this the age of puberty is lowered, so that girls who mature late are more easily injured and perish in greater number than the girls maturing earlier, who are less injured by the premature sexual intercourse. The male sex may have been influenced in the same direction through heredity.
Just as physical maturity, so is the cessation of generative power and bodily decline more marked in women than in men. In Middle and Northern Europe, procreation generally ceases with women of an age between forty-five and fifty years. Numerous birth statistics from all countries of this continent show that birth in women over fifty years old is very rare. It is not quite clear how the case stands in this respect among the coloured races. Hrdlička reports of the North American Indian women that with them the climacterium occurs apparently at about the same age as with European women. It must be taken into consideration that accurate statements of age are wanting, and that the age of Indian women can easily be greatly overrated. Otherwise it has generally been reported of coloured women that they age rapidly, and that their reproductive period is comparatively short. In North-west Brazil the Indian girls marry as soon as in their tenth to twelfth year, on account of their rapid development. Early maturity and marriage may be one of the chief causes of their rapid decline. The Indian women are generally beyond their prime at the age of twenty. Their straight figure is frequently covered with a disgusting accumulation of fat, and the elasticity of movement gives way to indolence. Other women become very thin after several confinements, their features become sharp and bony, and among old women one often comes across real hag-like creatures with half-blind, running eyes (Koch-Grünberg, II., p. 149).
In India the women of the Dravidian as well as of the Mongolian races age rapidly. Their generative power rarely lasts longer than the beginning of the forties. Among the pigmies the time of procreation is said to be equally short (Portman and Molesworth). Spencer and Gillen say that with the Australian women a rapid bodily decline takes place as early as the twenty-fifth and at the latest in the thirtieth year, which cannot be attributed to exceptional privations or harsh treatment. The Australian women apparently reach the age of fifty years or more only exceptionally.
Jochelson (pp. 413 et seq.) writes that the Koryak women age very rapidly. They cease to bear children at about the age of forty. Other travellers have made statements about the great age that the Koryaks are said to attain. Jochelson's thorough-going investigations showed that of 284 persons only thirteen could possibly have been over sixty-five years old, and among them there was only one really old man.
Schultze (p. 297) mentions two Hottentot women who had given birth at the age of forty-seven, and another who still had her period at fifty-five. Among the negresses late births also occur. Unfortunately, ethnographical literature only rarely gives facts with regard to this subject.
IX BIBLIOGRAPHY
Amundsen, R. Die Nordwestpassage. München, 1908.