IV VARIATION UNDER DOMESTICATION 101 



And it is not at all surprising that it should be so, since all 

 the species Avere in a state of nature when first domesticated 

 or cultivated by man, and whatever variations occur must be 

 due to purely natural causes. Moreover, on comparing the 

 variations which occur in any one generation of domesticated 

 animals with those Avhich we know to occur in Avild animals, 

 we find no evidence of greater individual variation in the 

 former than in the latter. The results of man's selection are 

 more striking to us because we have always considered the 

 varieties of each domestic animal to be essentially identical, 

 while those which Ave obserA^e in a Avild state are held to be 

 essentially diverse. The greyhound and the spaniel seem 

 Avonderful, as A^arieties of one animal produced by man's 

 selection ; Avhile Ave think little of the diA^ersities of the fox 

 and the Avolf, or the horse and the zebra, because Ave have 

 been accustomed to look upon them as radically distinct 

 animals, not as the results of nature's selection of the 

 varieties of a common ancestor. 



