"Laws Against Cousin Marriage: Would Eugenicists Alter Them?" (C. Davenport, H. Hunt, and G. Shull), Eugenics: A Journal of Race Betterment (vol II:8)

1732. Eugenics 23 Would Eugenicists Alter Them? [centered score] George H. Shull The marriage of first cousins as an occasional incident in the history of any portion of human society which happens to be free from obvious defect is of trivial significance from a biological point of view, and if there were no laws in existence against such marriages there would be very little biological ground for urging the establishment of such laws; on the other hand, with laws against cousin marriages almost generally in force, there is even less biological justification, it seems to me, for demanding their repeal. While our attitude toward problems of human eugenics must be guided largely by our knowledge of the genetics of other organisms, we must not lose sight of the fundamental differences in the objectives to be attained in man as compared with other animals and with plants, nor of the wholly different source of control of the process by which such objectives are to be approached. Wonderful progress was made in the improvement of wheat and other small grains when it was recognized that the best pure line for any given soil, climate and method of culture, could be promptly made the sole produce of a widely extended territory. To produce this result every other pure line must be sacrificed to make room for the one favored line. In Indian corn, in which the natural breeding habit is more nearly comparable to that in man, pure-line methods have been devised which have resulted in a great advance in arriving at maximum yields; but here, too, there is not only a great wastage involved in the elimination of most of the pure-lines, but the individuals selected for the matings are inferior instead of superior. In animals many of the finest breeds have been developed by the use of close inbreeding, -- even by brother-and-sister matings. Here again there has been a very high percentage of "wastage" resulting from the very restricted selection of the breeding animals. In man no such wastage could be tolerated; and besides, the objects so successfully striven for in plants and animals - the developing of each variety or breed to supply in maximal degree some narrowly restricted human need or desire - is not applicable to human eugenics. Man must be made broader and more versatile, not narrower and more fixed in character. Marriage of cousins, being a step in the direction of the pure-line methods, is not to be advocated as a desirable eugenical measure, even though the probably injurious effects of such matings diminish nearly to the vanishing point when there is no indication in collateral fraternities that any noticeable genotypic defects are carried in the group to which the cousins belong. The fact that the Darwin family resulted from a marriage of cousins is no more telling argument for cousin marriages, than is a single cousin marriage which produced idiotic or otherwise defective offspring an argument against such marriages. There is little doubt that there are more families of the latter class than of the former, and there is thus some justification for the traditional effort of society to protect itself by laws against close inbreeding. [lower left text beneath hairline rule] monly resorted to even though, as is recognized, the procedure is fraught with some danger. The question is raised concerning legal limitations to marriage. Law, like religion, has its roots in the distant past, at a time when scientific knowledge was not as developed as it is today. The original teachings may well have been based upon the knowledge extant at that time. It is unfortunate when they become so rigid that they can not be adjusted to meet expanding knowledge. [photo of author, upper left] [end]