SECONDARY SEXUAL CHARACTERS. 685 



occurred, especially during the earlier periods of our long 

 history. 



We will now examine a little more closely some of the 

 characters which distinguish the several races of man from 

 one another and from the lower animals, namely, the 

 greater or less deficiency of hair on the body and the color 

 of the skin. We need say nothing about the great diversity 

 in the shape of the features and of the skull between the 

 different races, as we have seen in the last chapter how dif- 

 ferent is the standard of beauty in these respects. These 

 characters will, therefore, probably have been acted on 

 through sexual selection; but we have no means of judging 

 whether they have been acted on chiefly from the male or 

 female side. The musical faculties of man have likewise 

 been already discussed. 



Absence of Hair on the Body and Its Development on 

 the Face and Head. From the presence of the woolly hair 

 or lanugo on the human fetus, and of rudimentary hairs 

 scattered over the body during maturity, we may infer that 

 man is descended from some animal Avhich was born hairy 

 and remained so during life. The loss of hair is an incon- 

 venience and probably an injury to man, even in a hot 

 climate, for he is thus exposed to the scorching of the sun, 

 and to sudden chills, especially during wet weather. As 

 Mr. Wallace remarks, the natives in all countries are glad 

 to protect their naked backs and shoulders with some 

 slight covering. No one supposes that the nakedness of 

 the skin is any direct advantage to man; his body, there- 

 fore, cannot have been divested of hair tlirough natural 

 selection.* Nor, as shown in a former chapter, have we 

 any evidence that this can be due to the direct action of 

 climate, or that it is the result of correlated development. 



The absence of hair on the body is to a certain extent a 



"Contributions to the Theory of Natural Selection," 1870, p. 

 346. Mr, Wallace believes (p. 350) "that some intelligent power 

 has guided or determined the development of n)an ;" and he con- 

 siders the hairless condition of the skin as coming under this 

 head. The Rev. T. R. Stebbing, in commenting on this view 

 ("Transactions of Devonshire Assoc, for Science," 1870) remarks, 

 that had Mr. Wallace "employed his usual ingenuity on the queS' 

 tion of man's hairless skin he might have seen the possibility of its 

 selection through its superior beauty or the health attaching to 

 superior cleanliness." 



