24 



THE EVOLUTION OE SEX. 



with the critical examination of infinitesimal variations of plumage on 

 which Darwin relies. Is not, therefore, his essential supposition too 

 glaringly anthropomorphic ? 



Again, the most beautiful males are often extremely combative; 

 and on the conventional view this is a mere coincidence, yet a most 

 unfortunate one for Mr. Darwin's view. Battle thus constantly decides 

 the question of pairing, and in cases where, by hypothesis, the female 

 should have most choice, she has simply to yield to the victor. On 

 our view, however, combative energy and sexual beauty rise pari passu 

 with male katabolism. 



Or again, in the Alneas group of the genus Papilio Darwin notes 

 how there are frequent gradations in the amount of difference between 

 the sexes. Sometimes the sexes are alike dull, where we should have 

 to suppose the aesthetic perception must somehow have been lost or 

 inhibited; sometimes the females are dull and the males splendid, — 

 for Darwin, an example of the result of sexual aesthetic perception, 

 this of an exquisitely subtle kind however, and without proportionate 

 cerebral enlargement. In a third set of cases, both sexes are splendid, 

 which would suggest logically that the male in turn had acquired a 

 taste for splendor. But such cases, which usually need more 

 or less cumbrous additional hypothesis of inheritance and so on to 

 explain them, are intelligible enough if we regard them as illustrations 

 of increasing katabolism throughout a series of species. The third set 

 may be supposed to be more male or katabolic than the first, while the 

 second set are midway; although it may be freely granted a knowledge 

 of the habits, size, &c. , of the particular species, would be necessary to 

 verify the legitimacy of this interpretation in this particular case.* 



It is necessary once more to turn to the contrast between the 

 positions of Darwin and Wallace. According to Darwin, sexual 

 selection, for love's sake, has accelerated the males into gay coloring; 

 according to Wallace, natural selection, for safety's sake, has retarded 

 the females (birds or butterflies) and kept them inconspicuously plain. 

 It is no longer difficult to establish a compromise. The true view 

 seems to be that both sexes have differentiated toward their respective 

 goals, but the males faster, because so katabolic; the limits are 

 constantly being fixed by natural selection in Wallace's cases, and as 

 constantly increased by sexual selection in Darwin's. There is, in 

 fact, no reason why both should not be admitted as minor factors; but 

 the greater part of the explanation is to be found in the view above 



* For a discussion of the progressive development of coloring and markings, 

 whether in butterflies or mammals, the reader may be referred to the works 

 of Professor Eimer, and especially to his forthcoming work on Lrpidoptera, 

 Reference should also be made to YYeismann's "Studies in the Theory ot 

 Descent," for a discussion of the markings of caterpillars and butterflies. 



