The Variation of Animals and Plants under Domestication — Volume 1. Darwin Charles

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СКАЧАТЬ there is a strong tendency to revert to the wild type; but that this tendency is largely governed by the nature of the climate, amount of exercise, and other causes of change to which they have been subjected.

      The last point worth notice is that we have unusually good evidence of breeds of pigs now keeping perfectly true, which have been formed by the crossing of several distinct breeds. The Improved Essex pigs, for instance, breed very true; but there is no doubt that they largely owe their present excellent qualities to crosses originally made by Lord Western with the Neapolitan race, and to subsequent crosses with the Berkshire breed (this also having been improved by Neapolitan crosses), and likewise, probably, with the Sussex breed. (3/30. S. Sidney's edition of 'Youatt on the Pig' 1860 pages 7, 26, 27, 29, 30.) In breeds thus formed by complex crosses, the most careful and unremitting selection during many generations has been found to be indispensable. Chiefly in consequence of so much crossing, some well-known breeds have undergone rapid changes; thus, according to Nathusius (3/31. 'Schweineschadel' s 140.), the Berkshire breed of 1780 is quite different from that of 1810; and, since this latter period, at least two distinct forms have borne the same name.

       CATTLE.

      Domestic cattle are certainly the descendants of more than one wild form, in the same manner as has been shown to be the case with our dogs and pigs. Naturalists have generally made two main divisions of cattle: the humped kinds inhabiting tropical countries, called in India Zebus, to which the specific name of Bos indicus has been given; and the common non-humped cattle, generally included under the name of Bos taurus. The humped cattle were domesticated, as may be seen on the Egyptian monuments, at least as early as the twelfth dynasty, that is 2100 B.C. They differ from common cattle in various osteological characters, even in a greater degree, according to Rutimeyer (3/32. 'Die Fauna der Pfahlbauten' 1861 s. 109, 149, 222. See also Geoffroy Saint-Hilaire in 'Mem. du Mus. d'Hist. Nat.' tome 10 page 172; and his son Isidore in 'Hist. Nat. Gen.' tome 3 page 69. Vasey in his 'Delineations of the Ox Tribe' 1851 page 127, says the zebu has four, and common ox five, sacral vertebrae. Mr. Hodgson found the ribs either thirteen or fourteen in number; see a note in 'Indian Field' 1858 page 62.) than do the fossil and prehistoric European species, namely, Bos primigenius and longifrons, from each other. They differ, also, as Mr. Blyth (3/33. 'The Indian Field' 1858 page 74 where Mr. Blyth gives his authorities with respect to the feral humped cattle. Pickering also in his 'Races of Man' 1850 page 274 notices the peculiar grunt-like character of the voice of the humped cattle.), who has particularly attended to this subject, remarks, in general configuration, in the shape of their ears, in the point where the dewlap commences, in the typical curvature of their horns, in their manner of carrying their heads when at rest, in their ordinary variations of colour, especially in the frequent presence of "nilgau-like markings on their feet," and "in the one being born with teeth protruding through the jaws, and the other not so." They have different habits, and their voice is entirely different. The humped cattle in India "seldom seek shade, and never go into the water and there stand knee-deep, like the cattle of Europe." They have run wild in parts of Oude and Rohilcund, and can maintain themselves in a region infested by tigers. They have given rise to many races differing greatly in size, in the presence of one or two humps, in length of horns, and other respects. Mr. Blyth sums up emphatically that the humped and humpless cattle must be considered as distinct species. When we consider the number of points in external structure and habits, independently of important osteological differences, in which they differ from each other; and that many of these points are not likely to have been affected by domestication, there can hardly be a doubt, notwithstanding the adverse opinion of some naturalists, that the humped and non-humped cattle must be ranked as specifically distinct.

      The European breeds of humpless cattle are numerous. Professor Low enumerates 19 British breeds, only a few of which are identical with those on the Continent. Even the small Channel islands of Guernsey, Jersey, and Alderney possess their own sub-breeds (3/34. Mr. H.E. Marquand in 'The Times' June 23, 1856.); and these again differ from the cattle of the other British islands, such as Anglesea, and the western isles of Scotland. Desmarest, who paid attention to the subject, describes 15 French races, excluding sub-varieties and those imported from other countries. In other parts of Europe there are several distinct races, such as the pale-coloured Hungarian cattle, with their light and free step, and enormous horns sometimes measuring above five feet from tip to tip (3/35. Vasey 'Delineations of the Ox-Tribe' page 124. Brace 'Hungary' 1851 page 94. The Hungarian cattle descend according to Rutimeyer 'Zahmen Europ. Rindes' 1866 s. 13 from Bos primigenius.): the Podolian cattle also are remarkable from the height of their fore-quarters. In the most recent work on Cattle (3/36. Moll and Gayot 'La Connaissance Gen. du Boeuf' Paris 1860. Fig. 82 is that of the Podolian breed.), engravings are given of fifty-five European breeds; it is, however, probable that several of these differ very little from each other, or are merely synonyms. It must not be supposed that numerous breeds of cattle exist only in long-civilised countries, for we shall presently see that several kinds are kept by the savages of Southern Africa.

      [With respect to the parentage of the several European breeds, we already know much from Nilsson's Memoir (3/37. A translation appeared in three parts in the 'Annals and Mag. of Nat. Hist.' 2nd series volume 4 1849.), and more especially from Rutimeyer's works and those of Boyd Dawkins. Two or three species or forms of Bos, closely allied to still living domestic races, have been found in the more recent tertiary deposits or amongst prehistoric remains in Europe. Following Rutimeyer, we have: Bos primigenius.

      This magnificent, well known species was domesticated in Switzerland during the Neolithic period; even at this early period it varied a little, having apparently been crossed with other races. Some of the larger races on the Continent, as the Friesland, etc., and the Pembroke race in England, closely resemble in essential structure B. primigenius, and no doubt are its descendants. This is likewise the opinion of Nilsson. Bos primigenius existed as a wild animal in Caesar's time, and is now semi-wild, though much degenerated in size, in the park of Chillingham; for I am informed by Professor Rutimeyer, to whom Lord Tankerville sent a skull, that the Chillingham cattle are less altered from the true primigenius type than any other known breed. (3/38. See also Rutimeyer 'Beitrage pal. Gesch. der Wiederkauer' Basel 1865 s. 54.)

      Bos trochoceros.

      This form is not included in the three species above mentioned, for it is now considered by Rutimeyer to be the female of an early domesticated form of B. primigenius, and as the progenitor of his frontosus race. I may add that specific names have been given to four other fossil oxen, now believed to be identical with B. primigenius. (3/39. Pictet 'Palaeontologie' tome 1 page 365 2nd edition. With respect to B. trochoceros see Rutimeyer 'Zahmen Europ. Rindes' 1866 s. 26.)

      Bos longifrons (or brachyceros) of Owen.

      This very distinct species was of small size, and had a short body with fine legs. According to Boyd Dawkins (3/40. W. Boyd Dawkins on the British Fossil Oxen 'Journal of the Geolog. Soc.' August 1867 page 182. Also 'Proc. Phil. Soc. of Manchester' November 14, 1871 and 'Cave Hunting' 1875 page 27, 138.) it was introduced as a domesticated animal into Britain at a very early period, and supplied food to the Roman legionaries. (3/41. 'British Pleistocene Mammalia' by W.B. Dawkins and W.A. Sandford 1866 page 15.) Some remains have been found in Ireland in certain crannoges, of which the dates are believed to be from 843-933 A.D. (3/42. W.R. Wilde 'An Essay on the Animal Remains, etc. Royal Irish Academy' 1860 page 29. Also 'Proc. of R. Irish Academy' 1858 page 48.) It was also the commonest form in a domesticated condition in Switzerland during the earliest part of the Neolithic period. Professor Owen (3/43. 'Lecture: Royal Institution of G. Britain' May 2, 1856 page 4. 'British Fossil Mammals' page 513.) thinks it probable that the Welsh and Highland cattle are descended from this form; as likewise is the case, according to Rutimeyer, with some of the existing Swiss breeds. These latter are of different shades of colour from light- grey to blackish-brown, with a lighter stripe along the spine, but they have no pure white marks. The cattle of North Wales and the Highlands, on the other hand, are generally black or dark-coloured.

      Bos frontosus of Nilsson.

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