98 THE HUMAN SPECIES 



sex ; this latter peculiarity may be considered as a secondary 

 sexual character like the long hair of the head in the female 

 sex. Darwin x infers from the lanugo of the human foetus, and 

 the rudimentary hairs scattered over the entire body during 

 maturity, that the progenitors of man were completely covered 

 with hair and that its gradual loss was probably due to sexual 

 selection, the character of nudity being first acquired by the 

 female sex and transmitted equally to both sexes ; Darwin 

 concludes that man first became divested of hair in the ab- 



FIG. 50. Transverse sections of hair (magn.). (Waldeyer.) I. Hair of the head : 

 a-c, of a brunette Jew ; d-k, of brunette and blonde Germans ; l-n, of a Negro ; 

 o-q, of a Japanese. II. Hair of the beard: r-v, of brunette and blonde 

 Germans; w-z, of a brunette Jew. 



dominal region, since the young chimpanzee is almost hairless 

 on the under surface of the body. 



A variety of reasons might be assigned for the loss of the 

 hairy covering, but to whatever cause it was actually due, the 

 process must have taken place in a warm climate. Klaatsch 

 suggests that it might also have been encouraged, or hindered, 

 by food as well as by climatic conditions. Sexual selection 

 may have played a part through the persistent eradication of the 

 hair from certain parts of the body (in the face of the woman, 



1 Darwin, loc. cit., vi., 354. 



