“The Descent of Man” 125 
The final section of this chapter deals with the formation of the 
races of mankind. Darwin discusses the question how far the direct 
effect of different conditions of life, or the inherited effects of in- 
creased use or disuse may have brought about the characteristic 
differences between the different races. Even in regard to the origin 
of the colour of the skin he rejects the transmitted effects of an 
original difference of climate as an explanation. In so doing he is 
following his tendency to exclude Lamarckian explanations as far as 
possible. But here he makes gratuitous difficulties from which, since 
natural selection fails, there is no escape except by bringing in the 
principle of sexual selection, to which, he regarded it as possible, 
skin-colouring, arrangement of hair, and form of features might 
be traced. But with his characteristic conscientiousness he guards 
himself thus: “I do not intend to assert that sexual selection will 
account for all the differences between the races}.” 
I may be permitted a remark as to Darwin’s attitude towards 
Lamarck. While, at an earlier stage, when he was engaged in the 
preliminary labours for his immortal work, The Origin of Species, 
Darwin expresses himself very forcibly against the views of Lamarck, 
speaking of Lamarckian “nonsense’,” and of Lamarck’s “absurd, 
though clever work®” and expressly declaring, “I attribute very 
little to the direct action of climate, etc.*” yet in later life he 
became more and more convinced of the influence of external con- 
ditions. In 1876, that is, two years after the appearance of the 
second edition of The Descent of Man, he writes with his usual 
candid honesty: “In my opinion the greatest error which I have 
committed, has been not allowing sufficient weight to the direct 
action of the environment, i.e. food, climate, etc. independently of 
natural selection®.” It is certain from this change of opinion that, 
if he had been able to make up his mind to issue a third edition of 
The Descent of Man, he would have ascribed a much greater in- 
fluence to the effect of external conditions in explaining the different 
characters of the races of man than he did in the second edition. 
He would also undoubtedly have attributed less influence to sexual 
selection as a factor in the origin of the different bodily characteristics, 
if indeed he would not have excluded it altogether. 
In Part III of the Descent two additional chapters are devoted to 
the discussion of sexual selection in relation to man. These may be 
very briefly referred to. Darwin here seeks to show that sexual 
selection has been operative on man and his primitive progenitor. 
Space fails me to follow out his interesting arguments. I can only 
mention that he is inclined to trace back hairlessness, the development 
1 Descent of Man, p. 308. 2 Life and Letters, Vol. 1. p. 23. 
3 Loe. cit. p. 39. 4 Loe, cit. (1856), p. 82. 5 Ibid. Vol. m1, p. 159. 
