Experimental Genetics and Human Evolution

Abstract

Planning based on informed foresight is the hallmark of organized human intelligence, in every theater from the personal decisions of domestic life to school bond elections to the world industrial economy. One sphere where it is hardly ever observed is the prediction and modification of human nature. The hazards of monolithic sophistocratic rationalization of fundamental human policy should not be overlooked, and medicine is wisely dedicated to the welfare of individual patients one at a time. However, though lacking machinery for global oversight, we must still find ways to cope with the population explosion, environmental pollution, clinical experimentation, the allocation of scarce resources like kidneys (transplant or artificial), even a convention on when life begins and ends, which confounds discussion of abortion and euthanasia. Concern for the biological substratum of posterity, i.e., eugenics, is divided by the same cross-purposes. Nevertheless, whether or not he dares to advocate concrete action, every student of evolution must be intrigued by what is happening to his own species (what else matters?), and especially the new evolutionary theory needed to model a self-modifying system that makes imperfect plans for its own nature. Repeated rediscovery notwithstanding, the eugenic controversy started in the infancy of genetic science. More recently, the integration of experimental genetics and biochemistry has provoked a new line of speculation about more powerful techniques than the gradual shift of gene frequencies by selective breeding for the modification of man. This article will first recapitulate a widely held skepticism about the criteria for the good man who is the aim of eugenic policy. The strategic impasse will not deter tactical assaults, but favors those with the most obvious, short-run payoff. I will then show how this points to an impending revision of the experimental design of human evolution, based on precedents already established in other species of animals and plants. The debate needed to ventilate these issues has started in a few conferences: Man and his future (G. Wolstenholme, ed.) Ciba Foundation Symposium, 1962; Control of human heredity and evolution (T. M. Sonneborn, ed.) MacMillan, 1965; and Biological aspects of social problems (Meade & Parkes, eds.) Plenum Press, 1965, which document many other ideas and references to primary literature. I would refer especially to Dobzhansky (1962) and Harris (1964) for outlines of the philosophical and technical foundations of the discussion. Despite every intention of generality, the outlook of this article is unavoidably culture-bound; many of my allusions pertain to academic life in