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Show 298 SEXUAL SELECTION: MAMMAL . I'Ait'l' JI. us to believe were primarily acquired by the males, have been transmitted equally, or almost equally, to both sexes· and we mav uow enquire how far this view may Le extended t~ mammals. With a considerable number of species, especially the smaller kinds, both sexes have been coloured, independently of sexual selection, for the sake of protection; but not, as far as I can judge, in so many cases, nor in nearly so striking a manner as in most of the lower classes. Audubon remarks that be often mistook the musk-rat/5 whilst sitting on the Lanks of a muddy stream, for a clod of earth, so complete \ras the resemblance. The hare on her form is a familiar instance of concealment through colour ; yet this principle partly fails in a closely-allied species, namely the rabbit, for as this animal runs to its burrow, it is made conspicuous to the sportsman and no doubt to all beasts of prey, by its uptumed pure-white taiL No one has ever doubted that the quadrupeds which inhabit snow-clad regions, have been rendered white to protect them from their enemies, or to favour their stealing on their prey. In regions where snow never lies long on the ground a white coat would be injurious; consequently species thus coloured are extremely rare in the hotter parts of the world. It deserves notice that many quadrupeds, inhabiting moderately cold regions, although they do not assume a ·white winter dress, become paler during this season; and this apparently is the direct result of the conditions to which they have long been exposed. Pallas 36 states that in Siberia a change of this nature occurs with the wolf, two species of 1\Iustcla, the domestic horse, tho Equus he- 3l Fiber zibelhicus, Alldubon and llnchmrm, ' Tho Quadrupeds of N. America,' 18-lG, p. 10!). 30 'Novro species QuadrU])(:Jnm o Glirium ordiuo,' 1778, p. 7. 'VI.1tt I have called the l'Oo is tlto Capreolus dibiricus suuecatrdalus of rallas. c; IIAL'. XVIII. EQUAL TRANSMISSION. 299 1nionus, tho domestic cow, two species of antelopes, the musk-deer, the roc, the elk, and reindeer. The roe, for instance, has a red summer and a greyish-white winter coat ; and the latter may perJ1aps serve as a protection to the animal whilst wandering through the leafless thickets, sprinkled with snow and hoar-frost. If the above named animals were gradually to extencl their range into regions perpetually covered with snow, their pale winter-coats woulrl probably be rendercJ, through natural selection, whiter and whiter by degrees, until they became as white as snow. Although we must admit that many quadrupeds have received their present tints as a protection, yet with a host of species, the colours arc far too com;picuous and too singularly arranged to allow us to suppose that they .'3erve for this purpose. vVo may take as an illustration certain antelopes: when we see that the square white patch on the throat, the white marks on the fetlocks, and the round black spots on the cars, are all more distinct in the male of the Portax picta, than in the female ;-when we see that the colours are more vivid, that tho narrow white lines on the flank and the broad white bar on the shoulder arc more distinct in the male Oreas Derbyanus than in the female;when we see a similar difference between the sexes of the curiously-ornamented Tragelaphus scriptus (fig. 68),-we may conclude that these colours an(l various marks have been at least intensified through sexual selection. It is inconceivable that such colours and marks can be of any direct or ordinary service to these animals; and as they have almost certainly been intensified through sexual selection, it is probable that they were originally gained through this same process, and then partially transferred to the females. If this view he admitted, there can be little doubt that the equally |