These are the physiological and generally unavoidable influences which went to the fixation of racial types. They are those which placed early man under the dominion of natural, unconscious evolution, like all the lower animals. To them may be added natural selection from accidental variations becoming permanent when proving of value in the struggle for existence, as shown in the black hue of equatorial tribes, special muscular development, etc.
But I do not look on these as the main agents in the fixation of special traits. No doubt such agencies primarily evolved them, but their cultivation and perpetuation were distinctly owing to conscious selection in early man. Our species is largely outside the general laws of organic evolution, and that by virtue of the self-consciousness which is the privilege of it alone among organized beings.
This conscious selection was applied in two most potent directions, the one to maintaining the physical ideal, the other toward sexual preference.
As soon as the purely physical influences mentioned had impressed a tendency toward a certain type on the early community, this was recognized, cultivated and deepened by man’s conscious endeavors. Every race, when free from external influence, assigns to its highest ideal of manly or womanly beauty its special racial traits, and seeks to develop these to the utmost. African travelers tell us that the negroes of the Soudan look with loathing on the white skin of the European; and in ancient Mexico when children were born of a very light color, as occasionally happened, they were put to death. On the other hand the earliest records of the white race exalt especially the element of whiteness. The writer of the Song of Solomon celebrates his bride as “fairest among women,” with a neck “like a tower of ivory;”[18] and one of the oldest of Irish hero-tales, the Wooing of Emer, chants the praises of “Tara, the whitest of maidens.”[19] Though both Greeks and Egyptians were of the dark type of the Mediterranean peoples, their noblest gods, Apollo and Osiris, were represented “fair in hue, and with light or golden hair.”[20]
The persistent admiration of an ideal leads to its constant cultivation by careful preservation and sexual selection. Thus the peoples who have little hair on the face and body, as most Chinese and American Indians, usually do not like any, and carefully extirpate it. The negroes prefer a flat nose, and a child which develops one of a pointed type has it artificially flattened. In Melanesia if a child is born of a lighter hue than is approved by the village, it is assiduously held over the smoke of a fire in order to blacken it. The custom of destroying infants markedly aberrant from the national type is nigh universal in primitive life. Such usages served to fix and perpetuate the racial traits.
A yet more powerful factor was sexual preference. This worked in a variety of ways. If is well known to stock breeders that the closer animals are bred in-and-in, that is, the nearer the relationship of father and mother, the more prominently the traits of the parents appear in their children and become fixed in the breed. It is evident that in the earliest epoch of the human family, the closest inter-breeding must have prevailed without restriction, as it does in every species of the lower animals. By its influences the racial traits were rapidly strengthened and indelibly impressed. This, however, was long before the dawn of history, for it is a most remarkable fact that never in historic times has a tribe been known that allowed incestuous relations, unless as in ancient Egypt and Persia, for a sacrificial or ceremonial purpose. The lowest Australians, the degraded Utes, look with horror on the union of brother and sister. The general principle of marriage in savage races is that of “exogamy,” marriage outside the clan or family, the latter being counted in the female line only. This strange but universal abhorrence has been explained by Darwin as primarily the result of sexual indifference arising between members of the same household, and the high zest of novelty in that appetite. Whatever the cause, the consequences will easily be seen. The racial traits once fixed in the period before this abhorrence arose would remain largely stationary afterwards, and by exogamous marriages would be rendered uniform over a wide area.
This form of conscious selection has properly been rated as one of the prime factors in the problem of race differentiation.[21] The apparently miscellaneous and violent union of the sexes in savage tribes is in fact governed by the most stringent traditional laws, and their confused cohabitations are so only to the mind of the European observer, not to the tribal conscience.[22]
Causes of Variation in Types.—The physical type once fixed by the influences just mentioned remains very stable; yet may fall under the influence of conditions which will greatly modify it.
Changes in climatic surroundings and of the food supply exert a visible effect. These generally come about by migration, though geologic action has occasionally completely altered the climate of a given locality, as at the glacial epoch, which change would have the same effect as migration.
How far migration may alter race-types after many generations is not yet defined. The Spanish-American of pure white blood, whose ancestors have lived for three centuries in tropical America, the citizen of the United States who traces his genealogy to the passengers in the Mayflower or the Welcome, have departed extremely little from the standard of the Andalusian or the Englishman of to-day, though the contrary is often asserted by those who have not personally studied the variants in the countries compared. Conditions of climate and food materially impress the individual, but not the race. The Greeks of Nubia are as dark as Nubians, but let their children return to Greece and the Nubian hue is lost. This is a general truth and holds good of all the slight impressions made upon pure races by unaccustomed environments.