106 INITIATIVE IN EVOLUTION 



The contrast between the straight, simple slope of the hair on the 

 lemur's and ape's back, and that of man is very great. In the 

 latter the side-streams make an angle of 45° or less with the axis 

 of the spine and this arrangement is unique among mammals. It 

 will be, therefore, necessary to inquire into its history and causation, 

 for it goes far towards reversing the well-established and accredited 

 pattern of apes, monkeys and lemurs. If the reader will carry 

 his mind back to the arrangement of hair on man 's forearm he will 

 see that it exhibits some features analogous to those on the back 

 of man. In the forearm there is that curious little stream on the 

 extensor surface which may be looked upon as a relic from the 

 ape-stock, but in the rest of that limb-segment man has boldly 

 gone back, beyond the ape, to an arrangement found in the lemur ; 

 and in the case of the back of man there is the small primitive 

 area down the vertebral furrow and an entirely novel arrangement 

 on each side such as might startle the leaders of animal fashions 

 in hair. 



The question at once arises : " How has this change come to 

 pass ? " In the case of the strange arrangement on man's forearms 

 I have shown that the Pan- Selectionist thought he detected there 

 one of his particular kinds of vestige. He cannot find any such 

 here. I can conceive a biologist making play with Heredity, 

 Variation and Selection in the case of an ape, monkey, or lemur 

 whose hairs are long and thick and functionally very active. There 

 he might make use of the well-known " argument from ignorance," 

 and maintain that we cannot be sure that such and such factors 

 might not have survival -value, but I defy the most hardy among 

 the Pan -Selectionist High Command to put in that plea in connection 

 with the fine short hairs of man which even require a lens for their 

 detection ; they have little value as a protection of the skin from 

 friction ; their arrangement has none. And if some leader did 

 attempt this task I doubt if the most docile Prussian would not 

 rebel against the statement that the withdrawal in question was 

 " according to plan." My purpose, however, in this book being 

 to build up and not to pull down, I must perforce show a reasonable 

 and better explanation of a remarkable little fact. 



Passive Habits. 



The habits of man concerned in the modus operandi of this 

 change are passive, and two in number ; that of sitting with his 

 back against some supporting object, and of lying in sleep with 

 his head more or less raised on a pillow or its equivalent. In 

 contrast with man, lemurs and apes inhabit trees during their 



