DARWIN 17 



which first produced organic life, and then originated con- 

 sciousness, came into play in order to develop the higher 

 intellectual and spiritual nature of man. This view was first 

 intimated in the last sentence of my paper on the " Develop- 

 ment of Human Races under Natural Selection," in 1864, 

 and more fully treated in the last chapter of my " Essays," 

 in 1870. 



These views caused much distress of mind to Darwin, but, 

 as I have shown, they do not in the least affect the general 

 doctrine of natural selection. It might be as well urged that 

 because man has produced the pouter-pigeon, the bull-dog, 

 and the dray-horse, none of which could have been produced 

 by natural selection alone, therefore the agency of natural 

 selection is weakened or disproved. Neither, I urge, is it 

 weakened or disproved if my theory of the origin of man is 

 the true one. 



2. Sexual Selection through Female Choice. — Darwin's 

 theory of sexual selection consists of two quite distinct parts — 

 the combats of males so common among polygamous mammals 

 and birds, and the choice of more musical or more ornamental 

 male birds by the females. The first is an observed fact, 

 and the development of weapons such as horns, canine teeth, 

 spurs, etc., is a result of natural selection acting through such 

 combats. The second is an inference from the observed facts 

 of the display of the male plumage or ornaments; but the 

 statement that ornaments have been developed by the female's 

 choice of the most beautiful male because he is the most beau- 

 tiful, is an inference supported by singularly little evidence. 

 The first kind of sexual selection I hold as strongly and as 

 thoroughly as Darwin himself; the latter I at first accepted, 

 following Darwin's conclusions from what appeared to be 

 strong evidence explicable in no other way ; but I soon came 

 to doubt the possibility of such an explanation, at first from 

 considering the fact that in butterflies sexual differences are 

 as strongly marked as in birds, and it was to me impossible to 

 accept female choice in their case, while, as the whole question 

 of colour came to be better understood, I saw equally valid 

 reasons for its total rejection even in birds and mammalia., 



