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Show 258 SEXUAL SELECTION : MAMMALS. PART II. Joubtful whether they arc of any service in their battles. With Antilope montana they exist only as rudiments in the young male, disappearing as he grows old; and they are absent in the female at all aO'es · but the females of certain other antelopes and dee~ have been known occasionally to exhibit rudiments of these teeth.28 Stallions have small canine tooth, which are either quite absent or rudimenta:y in the mare ; but they do not appear to be used m :fighting, for stallions bite with their incisors, and do not open their mouths widely like camels an~ guanacoes. Whenever the adult male possesses canmes now in an inefficient state, whilst the female has either none or mere rudiments, we may conclude that th~ early male proo·enitor of the species was provided with efficient canines which bad been partially transferred to the females. 'The reduction of these teeth in the males seems to have followed from some change in their manner of fighting, often caused (but not in the case of the horse) by the development of n~w ~eapons. Tusks and horns are manifestly of h1gh Importance to their possessors, for their development consu~es. much organised matter. A single tusk of ~he Asiatic elephant,- one of the extinct woolly speCI_es,-and o~ the African elephant, have been known to we1gh respect~vely 150, 160, and 180 pounds; and even gre~ter we1gh~s have been assigned by some authors.29 W1th deer, m 2s See Riippcll (in • Proc. Zoolog. Soc.' Jan. 12, 183~, p. 3) o_n the canines in deer and anlclopes, with a note by M:r. Mari1n on a lemalc American deer. See also Falconer (' Palroont. Memoirs and :Notes,' val. i. 1868, p. 576) on canines in an adult female d;er. I~_?ld males of the mu~k-deer the canines (Pallas,' pic. Zoolog. _fasc: xm. 1!79, P· 18) sometimes grow to tLc lcngt~1 of ~ln·co inches, wh1lst m old females n. rudiment projects scarcely half an mch above the gums. . . 1 ' ~n Emerson Tennent, 'Ceylon,' 1859, val. ii. p. 275; Owen, 'Bntls 1 Fossil Mammals,' 1846, p. 245. '<.: IIAP. XVII. LAW OF BATTLE. 259 which the horns are periodically 1·enewed, the drain on the constitution must be greater; the horns for instance, of the moose weigh from :fifty to sixty po~nds, .and those of the extinct Irish elk from sixty to seventy pounds,-tbe skull of the latter weighing on an average only five and a quarter pounds. With sheep, although ;the horns are not periodically renewed, yet their development, in the opinion of many agriculturists entails ~ sensib~e loss to the breeder. Stags, ~oreover, m escapmg from beasts of prey are loaded with an additi~nal ·w~ight for the race, and are greatly retarded m passmg through a woody country. The moose, for instance, with horns extending :five and a half feet fl'Om tip to tip, although so skilful in their use that he will not touch or break a dead twig when walking quietly, cannot act so dexterously whilst rushing away from a pack of wolves. "During his ·" progress he bolus his nose up, so as to lay the " horns horizontally back ; and in this attitude cannot "see the ground distinctly." 30 The tips of the horns of t~e great Irish elk were actually eight 'feet apart! Wh1lst the horns are covered with velvet, which lasts with the red-deer for about twelve weeks, they are extremely sensitive to a blow; so that in Germany the stags at this time change their habits to a certain extent, and a:oid dense forests, frequenting young woods and low tlnckets.31 These facts remind us, that male birds have acquired ornamental plumes at the ·cost of retarded flight, and other ornaments at the cost of some loss of power in their battles with rival males. 3n Richardson, 'Fauna Dar. Americana' on tho moose Alces palmata p. 236, 237; abo on tho expanse of the horns ' La~d and Water ·~ lSGD, p. 143 Sec also Owen, ' llriLish Fossil Mammals,' on the Irisl1 dk, p. 447, 455. 31 'Forest Creatures,' by C. Boner, 1861, p. 60. s 2 |