Bullseye
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« Reply #75 on: February 09, 2009, 01:31:34 pm » |
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* On the Gorilla, Savage and Wyman, Boston Journal of Natural History, vol. v., 1845-47, p. 423. On Cynocephalus, Brehm, Illustriertes Thierleben, B. i., 1864, s. 77. On Mycetes, Rengger, Naturgeschichte der Saugethiere von Paraguay, 1830, ss. 14, 20. On Cebus, Brehm, ibid., s. 108. *(2) Pallas, Spicilegia Zoolog., fasc. xii., 1777, p. 29. Sir Andrew Smith, Illustrations of the Zoology of S. Africa, 1849, pl. 29, on the Kobus. Owen, in his Anatomy of Vertebrates (vol. iii., 1868, p. 633) gives a table shewing incidentally which species of antelopes are gregarious. *(3) Dr. Campbell, in Proc., Zoolog. Soc., 1869, p. 138. See also an interesting paper by Lieut. Johnstone, in Proceedings, Asiatic Society of Bengal, May, 1868. *(4) Dr. Gray, in Annals and Magazine of Natural History, 1871, p. 302. *(5) See Dr. Dobson's excellent paper in Proceedings of the Zoological Society, 1873, p. 241.
As I hear from Sir Andrew Smith, the lion in South Africa sometimes lives with a single female, but generally with more, and, in one case, was found with as many as five females; so that he is polygamous. As far as I can discover, he is the only polygamist amongst all the terrestrial Carnivora, and he alone presents well-marked sexual characters. If, however, we turn to the marine Carnivora, as we shall hereafter see, the case is widely different; for many species of seals offer extraordinary sexual differences, and they are eminently polygamous. Thus, according to Peron, the male sea-elephant of the southern ocean always possesses several females, and the sea-lion of Forster is said to be surrounded by from twenty to thirty females. In the North, the male sea-bear of Steller is accompanied by even a greater number of females. It is an interesting fact, as Dr. Gill remarks,* that in the monogamous species, "or those living in small communities, there is little difference in size between the males and females; in the social species, or rather those of which the males have harems, the males are vastly larger than the females."
* "The Eared Seals," American Naturalist, vol. iv., Jan. 1871.
Amongst birds, many species, the sexes of which differ greatly from each other, are certainly monogamous. In Great Britain we see well-marked sexual differences, for instance, in the wild-duck which pairs with a single female, the common blackbird, and the bullfinch which is said to pair for life. I am informed by Mr. Wallace that the like is true of chatterers or Cotingidae of South America, and of many other birds. In several groups I have not been able to discover whether the species are polygamous or monogamous. Lesson says that birds of paradise, so remarkable for their sexual differences, are polygamous, but Mr. Wallace doubts whether he had sufficient evidence. Mr. Salvin tells me he has been led to believe that humming-birds are polygamous. The male widow-bird, remarkable for his caudal plumes, certainly seems to be a polygamist.* I have been assured by Mr. Jenner Weir and by others, that it is somewhat common for three starlings to frequent the same nest; but whether this is a case of polygamy or polyandry has not been ascertained.
* The Ibis, vol. iii., 1861, p. 133, on the Progne widow-bird. See also on the Vidua axillaris, ibid., vol. ii., 1860, p. 211. On the polygamy of the capercailzie and great bustard, see L. Lloyd, Game Birds of Sweden, 1867, pp. 19, and 182. Montagu and Selby speak of the black grouse as polygamous and of the red grouse as monogamous.
The Gallinaceae exhibit almost as strongly marked sexual differences as birds of paradise or humming-birds, and many of the species are, as is well know, polygamous; others being strictly monogamous. What a contrast is presented between the sexes of the polygamous peacock or pheasant, and the monogamous guinea-fowl or partridge! Many similar cases could be given, as in the grouse tribe, in which the males of the polygamous capercailzie and black-**** differ greatly from the females; whilst the sexes of the monogamous red grouse and ptarmigan differ very little. In the Cursores, except amongst the bustards, few species offer strongly-marked sexual differences, and the great bustard (Otis tarda) is said to be polygamous. With the Grallatores, extremely few species differ sexually, but the ruff (Machetes pugnax) affords a marked exception, and this species is believed by Montagu to be a polygamist. Hence it appears that amongst birds there often exists a close relation between polygamy and the development of strongly-marked sexual differences. I asked Mr. Bartlett, of the Zoological Gardens, who has had very large experience with birds, whether the male tragopan (one of the Gallinaceae) was polygamous, and I was struck by his answering, "I do not know, but should think so from his splendid colours." It deserves notice that the instinct of pairing with a single female is easily lost under domestication. The wild-duck is strictly monogamous, the domestic-duck highly polygamous. The Rev. W. D. Fox informs me that out of some half-tamed wild-ducks, on a large pond in his neighborhood, so many mallards were shot by the game-keeper that only one was left for every seven or eight females; yet unusually large broods were reared. The guinea-fowl is strictly monogamous; but Mr. Fox finds that his birds succeed best when he keeps one **** to two or three hens. Canary-birds pair in a state of nature, but the breeders in England successfully put one male to four or five females. I have noticed these cases, as rendering it probable that wild monogamous species might readily become either temporarily or permanently polygamous.
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