NATURAL SELECTION IN WAR 



Conclusions as to Eugenic Results of Conflict Cannot Be Drawn Without Inquiry 



As to Very Large Number of Different Factors War May Either 



Help or Hinder Race Betterment — Present Strife is 



Overwhelmingly Dysgenic in Effect 



RoswELL H. Johnson 

 University of Pittsburgh, Pittsburgh, Pa. 



THE unqualified statement that 

 war is either eugenic or dysgenic 

 in its effect on the human race, 

 is found, on closer investigation 

 to be unjustifiable. The modification of 

 selection by war is far more manifold 

 than the literature on the biological 

 effects of war wotdd lead the reader to 

 suppose. All wars are partly eugenic 

 and partly dysgenic. Some are mainly 

 eugenic and others mainly dysgenic. 



Natural selection should be sub- 

 divided into (1) lethal, that which 

 operates through differential mortality; 

 (2) sexual, that which operates through 

 differential mating; and (3) fecundal, 

 that which o]jeratcs through differential 

 fecundity. Again, selection operates 

 both in an inter-group competition and 

 an intra-group competition. We must, 

 then, in analyzing the influence of any 

 agency on natural selection, examine it 

 under each of these six heads. In the 

 case of war, however, we may eliminate 

 fecundal selection, as it is little influ- 

 enced. Still another division arises from 

 the fact that the action of selection is 

 different during a war ui)on the armed 

 forces themselves and upon the jxjpula- 

 tion at home; and after the war, u]jon 

 the nations with the various modifica- 

 tions that the war has left. 



Wc will consider lethal selection first. 

 To measure the effect of the inter-group 

 selection of the armed forces, we have 

 to comi)are the relative quality of the 

 two races involved. The evidence for 

 believing in sul)stantial differences be- 

 tween races is based (a) ujxjn their rela- 

 tive achievement when each is isolated, 

 (6) upon the relative rank when the 

 two are competing in one society, and 

 546 



(c) upon the relative number of original 

 contributions to civilization each has 

 made. Such comparisons lead us to 

 reject the sentimental equalitarianism 

 that denies race differences. While we 

 admit of course a great deal of over- 

 lapping, there are, nevertheless, real 

 average differences. To think other- 

 wise is to discard evolution and revert 

 to the older standpoint of "special 

 creation." 



The comparison of the quality of the 

 two sides becomes more and more 

 difficult as fighting is more and more 

 between groups of allies which may 

 differ greatly among themselves. Yet 

 this b}^ no means removes the inequality 

 of the two sides taken each as a whole. 



Without entering into the e\4dence 

 at this time, we readily see that the 

 eugenic effect of war would be very 

 different according as the sides differ 

 much or little. Yet this difference in 

 quality, however great, will have no 

 significance, unless the superior or 

 inferior side is in general more likely to 

 lose fewer men. Where the difference 

 has been considerable, as between a 

 civilized and savage nation, it has been 

 seldom that the superior does not 

 triumph with fewer losses. \'ictory, 

 however, is influenced much less in 

 these later days by the relative military 

 efficiency of two single nations than by 

 the success in making alliances with 

 I)owerful nations. But such alignments 

 are l)y no means always associated with 

 better quality, because (a) there is a 

 natural tendency for the weak to unite 

 against a strong nation, (b) to side with 

 a group which is aj^parently succeeding, 

 and (c) the alliances mav be tlie work 



