Natural selection in human populations : the measurement of ongoing genetic evolution in contemporary societies / edited Carl Jay Bajema.

Date:
[1971]
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: Natural selection in human populations : the measurement of ongoing genetic evolution in contemporary societies / edited Carl Jay Bajema. Source: Wellcome Collection.

    27/420 (page 15)
    Man and Natural Selection 15 glasses. The effort needed to eradicate or to reduce the frequency of myopia geneti¬ cally would exceed that requisite to rectify their defect environmentally, by manu¬ facturing more pairs of glasses. Diabetes mellitus is, given the present level of medicine, more difficult and expensive to correct than is myopia. Some diabetics may nevertheless be treated successfully by insulin therapy, helped to live to old age, and enabled to raise fami¬ lies as large as nondiabetics. The incidence of diabetes may therefore creep up slow¬ ly in the generations to come. Now, most people would probably agree that it is better to be free of diabetes than to have it under control, no matter how success¬ fully, by insulin therapy or other means. The prospect is not a pleasant one to contemplate. Insulin injections may perhaps be almost as common in some remote future as taking aspirin tablets is at present. Towards Guidance of Human Evolution Are we, then, faced with a dilemma—if we enable the weak and the deformed to live and to propagate their kinds, we face the prospect of a genetic twilight; but if we let them die or suffer when we can save them we face the certainty of a moral twilight. How to escape this dilemma? I can well understand the impatience which some of my readers may feel if I re¬ fuse to provide an unambiguous answer to so pressing a problem. Let me however plead with you that infatuation with over-simple answers to very complex and diffi¬ cult problems is one of the earmarks of intellectual mediocrity. I am afraid that the problem of guidance of human evolution has no simple solution. At least I have not found one, nor has anybody else in my opinion. Each genetic condition will have to be considered on its own merits, and the solution which may be adopted for differ¬ ent conditions will probably be different. Suppose that everybody agrees that the genes causing myopia, achondroplasia, diabetes and retinoblastoma are undesirable. We shall nevertheless be forced to treat them differently. Some genetic defects will have to be put up with and managed environmentally ; others will have to be treated genetically, by artificial selection, and the eugenic measures that may be needed can be effected without accepting any kind of biological Brave New World. Let us face this fact: Our lives depend on civilization and technology, and the lives of our descendants will be even more dependent on civilized environments. I can imagine a wise old ape-man who deplored the softness of his contemporaries using stone knives to carve their meat instead of doing this with their teeth; or a solid conservative Peking man viewing with alarm the new fangled habit of using fire to make oneself warm. I have yet to hear anyone seriously proposing that we give up the use of knives and of fire now. Nor does anyone in his right mind urge that we let people die of smallpox or tuberculosis, in order that genetic resistance to these diseases be maintained. The remedy for our genetic dependence on