Page:Popular Science Monthly Volume 81.djvu/484

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the race by improving the environment and we know that effects of an improved environment are not inherited, how have we left the euthenist a leg to stand upon? The question seems to be one too simple to need discussion. But it is not so simple. Even granting the non-inheritance of acquired characters, the proper place of environment in a eugenic program is not a simple question. In the first place, it is very difficult to separate out those characters which are the results of inborn determinants (inherited) from those which are produced solely by reaction to environment. Or it may be, as is probably usually the case, that both influences are at work in the expression of the same character. Size may be cited as an example. Undoubtedly a child inherits the tendency to acquire a particular size; but whether it fails to reach this size or exceeds it, is in large part dependent on environmental factors which influence growth, such as food-supply, fresh air, exercise and undoubtedly many others.

But it may be, and has been, asked, granting in full the part played by heredity, is it not possible that a permanent environment may be created of such a nature that the outcome will be the same whatever the hereditary nature of the individual? Undoubtedly such may be true in certain restricted cases. For example, if a mosquitoless environment could be established and maintained, what would it matter whether we, individually possessed or lacked a natural (inherited) susceptibility to malaria and yellow fever? It is also possible that as the skill of the surgeon and the ingenuity of the bacteriologist increase, we shall be able by means of the injection of antitoxin and the removal or replacement of organs to disregard the inheritance of many diatheses and bodily imperfections. This would require, however, the maintenance of a highly "artificial" environment, and the resulting picture is not one which appeals to us as our ideal type of mankind. It will require much further study to teach us in how far such a condition of affairs may be desirable, and only the future can show how much it may be a necessary result of the multifarious interacting forces of evolution.

Moreover, the cases of this nature must be relatively few—in the great majority, as has just been pointed out, the environment can act only when the necessary hereditary basis is present. We should predict poor success to the stockman who depended entirely upon feeding and care to produce the maximum of marketable beef, or the dairyman who by these means alone expected to compete with herds of selected animals in the production of milk.

Inherent quality is what determines the value of a gem; grinding and polishing only serve to bring out its luster and brilliance, and no amount of labor expended by the lapidary can convert a piece of quartz into a diamond. Selection of specimens which have the inherent qualities is the essential. The breeder knows this, and he realizes the im-