528 THE DESCENT OF MAN. 



Other by the throat; but it is not probable that the beard has 

 been developed for a distinct purpose from that served by the 

 ■whiskers, moustache, and other tufts of hair on the face; and 

 no one will suppose that these are useful as a protection. Must 

 we attribute all these appendages of Hair or skin to mere pur- 

 poseless variability in the male? It cannot be denied that this 

 is possible; for in many domesticated quadrupeds, certain char- 

 acters, apparently not derived through reversion from any wild 

 parent-form, are confined to the males, or are more developed In 

 them than in the females — for instance, the hump on the male 

 zebu-cattle of India, the tail of fat-tailed rams, the arched out- 

 line of the forehead in the males of several breeds of sheep, and, 

 lastly, the mane, the long hairs on the hind-legs, and the dewlap 

 of the male of the Berbura goat.'' The mane, which occurs only 

 in the rams of an African breed of sheep, is a true secondary sex- 

 ual character, for, as I hear from Mr. Winwood Reade, it is not 

 developed if the animal be castrated. Although we ought to be 

 extremely cautious, as shown in my work on 'Variation under 

 Domestication,' in concluding that any character, even with ani- 

 mals kept by semi-civilized people, has not been subjected to 

 selection by man, and thus augmented, yet in the cases just speci- 

 fied this is improbable; more especially as the characters are 

 confined to the males, or are more strongly developed in them 

 than in the females. If it were positively known that the above 

 African ram is a descendant of the same primitive stock as the 

 other breeds of sheep, and if the Berbura male-goat with his 

 mane, dewlap, &c., is descended from the same stock as other 

 goats, then, assuming that selection has not been applied to these 

 characters, they must be due to simple variability, together with 

 sexually-limited inheritance. 



Hence it appears reasonable to extend this same view to all 

 analogous cases with animals in a state of nature. Nevertheless 

 I cannot persuade myself that it generally holds good, as in the 

 case of the extraordinary development of hair on the throat and 

 fore-legs of the male Ammotragus, or in that of the immense 

 beard of the male Pithecia. Such study as I have been able to 

 give to nature makes me believe that parts or organs which are 

 highly developed, were acquired at some period for a special 

 purpose. With those antelopes in which the adult male is more 

 strongly-colored than the female, and with those monkeys in 

 which the hair on the face is elegantly arranged and colored in 

 a diversified manner, it seems probable that the crests and tufts 



1* See the chapters on these several animals in vol. i. of my 'Varia- 

 tion of Animals under Domestication;' also, vol. ii. p. 73; also, chap. 

 XX. on the practice of selection by semi-civilized people. For the Ber- 

 bura goat, see Dr. Gray, 'Catalogue,' ibid. p. 157. 



