662 THE DESCENT OF MAN 



■which it appears that the horns of a deer in one district 

 in the United States are now being modified through sex- 

 ual and natural selection. A writer in an excellent Ameri- 

 can journal " says that he has hunted for the last twenty-one 

 years in the Adirondacks, where the Cervus virginianus 

 abounds. About fourteen years ago he first heard of spike' 

 horn bucks. These became from year to year more common ; 

 about five years ago he shot one, and afterward another, and 

 now they are frequently killed. "The spike-horn differs 

 greatly from the common antler of the G. virginianus. It 

 consists of a single spike, more slender than the antler, 

 and scarcely half so long, projecting forward from the 

 brow, and terminating in a very sharp point. It gives a 

 considerable advantage to its possessor over the common 

 buck. Besides enabling him to run more swiftly through 

 the thick woods and underbrush (every hunter knows that 

 does and yearling bucks run much more rapidly than the 

 large bucks when armed with their cumbrous antlers), 

 the spike-horn is a more effective weapon than the com- 

 mon antler. With this advantage the spike-horn bucks 

 are gaining upon the common bucks, and may, in time, 

 entirely supersede them in the Adirondacks. Undoubt- 

 edly, the first spike-horn buck was merely an accidental 

 freak of nature. But his spike-horns gave him an advan- 

 tage, and enabled him to propagate his peculiarity. His 

 descendants, having a like advantage, have propagated 

 the peculiarity in a constantly increasing ratio, till they 

 are slowly crowding the antlered deer from the region 

 they inhabit." A critic has well objected to this account 

 by asking why, if the simple horns are now ' so advan- 

 tageous, were the branched antlers of the parent form ever 

 developed ? To this I can only answer by remarking that 

 a new mode of attack with new weapons might be a great 

 advantage, as shown by the case of the Ovis cycloceros, 

 who thus conquered a domestic ram famous for his fight- 



* "The American Naturalist," Dec. 1869, p. 552. 



