(a) To this view is opposed the theory, propounded by Agassiz, of different centres of creation, and of different types of humanity corresponding to the varying fauna and flora of each. But this theory makes the plural origin of man an exception in creation. Science points rather to a single origin of each species, whether vegetable or animal. If man be, as this theory grants, a single species, he should be, by the same rule, restricted to one continent in his origin. This theory, moreover, applies an unproved hypothesis with regard to the distribution of organized beings in general to the very being whose whole nature and history show conclusively that he is an exception to such a general rule, if one exists. Since man can adapt himself to all climes and conditions, the theory of separate centres of creation is, in his case, gratuitous and unnecessary.
Agassiz's view was first published in an essay on the Provinces of the Animal World, in Nott and Gliddon's Types of Mankind, a book gotten up in the interest of slavery. Agassiz held to eight distinct centres of creation, and to eight corresponding types of humanity—the Arctic, the Mongolian, the European, the American, the Negro, the Hottentot, the Malay, the Australian. Agassiz regarded Adam as the ancestor only of the white race, yet like Peyrerius and Winchell be held that man in all his various races constitutes but one species.
The whole tendency of recent science, however, has been adverse to the doctrine of separate centres of creation, even in the case of animal and vegetable life. In temperate North America there are two hundred and seven species of quadrupeds, of which only eight, and these polar animals, are found in the north of Europe or Asia. If North America be an instance of a separate centre of creation for its peculiar species, why should God create the same species of man in eight different localities? This would make man an exception in creation. There is, moreover, no need of creating man in many separate localities; for, unlike the polar bears and the Norwegian firs, which cannot live at the equator, man can adapt himself to the most varied climates and conditions. For replies to Agassiz, see Bib. Sac., 19:607-632; Princeton Rev., 1862:435-464.
(b) It is objected, moreover, that the diversities of size, color, and physical conformation, among the various families of mankind, are inconsistent with the theory of a common origin. But we reply that these diversities are of a superficial character, and can be accounted for by corresponding [pg 482] diversities of condition and environment. Changes which have been observed and recorded within historic times show that the differences alluded to may be the result of slowly accumulated divergences from one and the same original and ancestral type. The difficulty in the case, moreover, is greatly relieved when we remember (1) that the period during which these divergences have arisen is by no means limited to six thousand years (see note on the antiquity of the race, pages 224-226); and (2) that, since species in general exhibit their greatest power of divergence into varieties immediately after their first introduction, all the varieties of the human species may have presented themselves in man's earliest history.
Instances of physiological change as the result of new conditions: The Irish driven by the English two centuries ago from Armagh and the south of Down, have become prognathous like the Australians. The inhabitants of New England have descended from the English, yet they have already a physical type of their own. The Indians of North America, or at least certain tribes of them, have permanently altered the shape of the skull by bandaging the head in infancy. The Sikhs of India, since the establishment of Bába Nának's religion (1500 A. D.) and their consequent advance in civilization, have changed to a longer head and more regular features, so that they are now distinguished greatly from their neighbors, the Afghans, Tibetans, Hindus. The Ostiak savages have become the Magyar nobility of Hungary. The Turks in Europe are, in cranial shape, greatly in advance of the Turks in Asia from whom they descended. The Jews are confessedly of one ancestry; yet we have among them the light-haired Jews of Poland, the dark Jews of Spain, and the Ethiopian Jews of the Nile Valley. The Portuguese who settled in the East Indies in the 16th century are now as dark in complexion as the Hindus themselves. Africans become lighter in complexion as they go up from the alluvial river-banks to higher land, or from the coast; and on the contrary the coast tribes which drive out the negroes of the interior and take their territory end by becoming negroes themselves. See, for many of the above facts, Burgess, Antiquity and Unity of the Race, 195-202.
The law of originally greater plasticity, mentioned in the text, was first hinted by Hall, the palæontologist of New York. It is accepted and defined by Dawson, Story of the Earth and Man, 360—“A new law is coming into view: that species when first introduced have an innate power of expansion, which enables them rapidly to extend themselves to the limit of their geographical range, and also to reach the limit of their divergence into races. This limit once reached, these races run on in parallel lines until they one by one run out and disappear. According to this law the most aberrant races of men might be developed in a few centuries, after which divergence would cease, and the several lines of variation would remain permanent, at least so long as the conditions under which they originated remained.” See the similar view of Von Baer in Schmid, Theories of Darwin, 55, note. Joseph Cook: Variability is a lessening quantity; the tendency to change is greatest at the first, but, like the rate of motion of a stone thrown upward, it lessens every moment after. Ruskin, Seven Lamps, 125—“The life of a nation is usually, like the flow of a lava-stream, first bright and fierce, then languid and covered, at last advancing only by the tumbling over and over of its frozen blocks.” Renouf, Hibbert Lectures, 54—“The further back we go into antiquity, the more closely does the Egyptian type approach the European.” Rawlinson says that negroes are not represented in the Egyptian monuments before 1500 B. C. The influence of climate is very great, especially in the savage state.
In May, 1891, there died in San Francisco the son of an interpreter at the Merchants' Exchange. He was 21 years of age. Three years before his death his clear skin was his chief claim to manly beauty. He was attacked by “Addison's disease,” a gradual darkening of the color of the surface of the body. At the time of his death his skin was as dark as that of a full-blooded negro. His name was George L. Sturtevant. Ratzel, History of Mankind, 1:9, 10—As there is only one species of man, “the reunion into one real whole of the parts which have diverged after the fashion of sports” is said to be “the unconscious ultimate aim of all the movements” which have taken place since man began his wanderings. “With Humboldt we can only hold fast to the external unity of the race.” See Sir Wm. Hunter, The Indian Empire, 223, 410; Encyc. Britannica, 12:808; 20:110; Zöckler, Urgeschichte, 109-132, and in Jahrbuch für deutsche [pg 483]Theologie, 8:51-71; Prichard, Researches, 5:547-552, and Nat. Hist. of Man, 2:644-656; Duke of Argyll, Primeval Man, 96-108; Smith, Unity of Human Races, 255-283; Morris, Conflict of Science and Religion, 325-385; Rawlinson, in Journ. Christ. Philosophy, April, 1883:359.