Mixed Race Studies

One of the most fruitful sources of genetic variation in man is race mixture. Although the term is something of a misnomer, its usage is firmly established. Actually anything from the latest international marriage of an American heiress with a British peer to the miscegenation of Australian aborigines with Europeans is called race mixture. In no case does race mixture in man represent the crossing of pure-line races such as might be possible in the laboratory, for pure-line human races do not exist. The very fact that pure human races are not to be found in nature—a situation which, paradoxically, “race mixture” has done much to bring about—makes it impossible to draw a hard and fast line between miscegenation of related peoples and the crossing of genetically distinct populations. The process of mixture, however, whether or not between closely related or widely diverse stocks is one that tends to create new gene combinations and therefore increased variation. The gene distributions which are known, the geographic continuities of physical variation and the prehistoric as well as the historic records are abundant evidence for the belief that mixture has always been a significant factor in man’s past. That it will involve a larger proportion of the world’s population in the future is not unlikely in view of the increasing contacts between the peoples of the earth. In the New World great areas are even now inhabited by populations of mixed blood. In the colonial empires of European nations, half-caste groups quickly become established. The migrations and resettlements of the past which brought millions of diverse Europeans to the United States, the dislocations of the present war, the opening up of Asiatic Russia, also provide fertile opportunities for reshuffling the genes of mankind. Up to the present only a handful of students have concerned themselves with the biological consequences of race mixture. Propagandists and Nordophiles like Madison Grant, echoing the racist literature of Germany, see nothing but evil in the process. At least, the evil was inevitable as far as the Nordics were concerned, for in the view of the racists the manifest supremacy of the Nordics could only suffer deterioration by miscegenation since they had no peer with which to mingle in equality. Although this extreme view was characteristic mainly of certain popular writers distinguished by their zeal rather than their scientific attainments, several geneticists have suggested that in crossing divergent races serious disharmonies were likely to develop. Castle among others has effectively disproved these claims, but there still lingers a common belief that the mulatto, for example, is inferior, at least physically, to either Negro or white. The high rate of tuberculosis among mulattoes is sometimes cited as evidence of this. Careful studies of the environment, however, usually reveals that in this condition other factors than race are determinants.

Contrary to belief that race mixture leads to deterioration, an actual superiority in some instances may characterize the half-caste population. Fischer’s study of the Rehobother Bastards, a cross between South African Boers and Hottentots (certainly as divergent a pair of stocks as might be expected to mate) disclosed evidence of a hybrid vigor which in fertility surpassed the performances of either Boers or Hottentots. In a study of the Polynesian-English descendants of the Mutineers of the Bounty, I found in the early generations a marked superiority over the parental stocks not only in physical size but also in the birth rate. Boas’s investigations on half-breed Indians indicated something of the same order. Such a phenomenon as hybrid vigor or heterosis is well known in biology and is now commercially applied in the propagation of hybrid corn, whose increased yields over pure-line strains has led to its wide adoption in agriculture. Experimental animals display the same results in certain crosses. There is then every reason to suppose that the increase of size, vigor, and fertility which is sometimes found in human hybrids is part of the same general biological principle. While it would be erroneous to assume that race mixture in every case leads to an enhanced biological status, it is worth considering as one of the possible explanations of the recurrent epochs of outstanding intellectual activity that mark European history. The intermingling of various strains that preceded the classic development of Greece and the miscegenation that accompanied the “Volkerwanderung” of the millennium before the Renaissance suggest that an unusually active reshuffling of genes produces a heightened vitality that finds expression in high peaks of civilization. This is not a novel construction of European history, but it does receive added credence from recent observations on race mixture.

H. L. Shapiro, “Society and Biological Man,” The Science of Man in the World Crisis, Ralph Linton, ed., (New York: Columbia University Press, 1945).