Chap. VIII. 
SEXUAL SELECTION. 
267 
more frequently present sexual differences than almost 
any other group of mammals, especially in their weapons, 
but likewise in other characters. Most deer, cattle, and 
sheep are polygamous ; as are most antelopes, though 
some of the latter are monogamous. Sir Andrew 
Smith, in speaking of the antelopes of South Africa, 
says that in herds of about a dozen there was rarely 
more than one mature male. The Asiatic Antilope 
saiga appears to be the most inordinate polygamist 
in the world; for Pallas 6 states that the male drives 
away all rivals, and collects a herd of about a hundred, 
consisting of females and kids : the female is hornless 
and has softer hair, but does not otherwise differ much 
from the male. The horse is polygamous, but, except 
in his greater size and in the proportions of his body, 
differs but little from the mare. The wild boar, in liis 
great tusks and some other characters, presents well- 
marked sexual characters ; in Europe and in India he 
leads a solitary life, except during the breeding-season ; 
but at this season he consorts in India with several 
females, as Sir W. Elliot, who has had large experience 
in observing this animal, believes : whether this holds 
good in Europe is doubtful, but is supported by some 
statements. The adult male Indian elephant, like the 
boar, passes much of his time in solitude; but when 
associating with others, “it is rare to find,” as Dr. 
Campbell states, “more than one male with a whole 
“ herd of females.” The larger males expel or kill the 
smaller and w T eaker ones. The male differs from the 
female by his immense tusks and greater size, strength, 
and endurance ; so great is the difference in these latter 
6 Pallas, ‘ Spicilegia Zoolog.’ Fasc. xii. 1777, p. 29. Sir Andrew 
Smith, ‘ Illustrations of the Zoology of S. Africa/ 1849, pi. 29, on the 
Kobus. Owen, in his ‘Anatomy of Vertebrates’ (vol. iii. 1868, p. 633) 
gives a table incidentally showing which species of Antelopes pair and 
which are gregarious. , 
