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

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СКАЧАТЬ be followed, though an unfortunate one, as the wild aboriginal does not inhabit India, and the best-known domesticated breeds have been imported from Siam and China.

      First for the Sus scrofa breeds, or those resembling the common wild boar. These still exist, according to Nathusius ('Schweineschadel' s. 75), in various parts of central and northern Europe; formerly every kingdom (3/2. Nathusius 'Die Racen des Schweines' Berlin 1860. An excellent appendix is given with references to published and trustworthy drawings of the breeds of each country), and almost every province in Britain, possessed its own native breed; but these are now everywhere rapidly disappearing, being replaced by improved breeds crossed with the S. indicus form. The skull in the breeds of the S. scrofa type resembles, in all important respects, that of the European wild boar; but it has become ('Schweineschadel' s. 63-68) higher and broader relatively to its length; and the hinder part is more upright. The differences, however, are all variable in degree. The breeds which thus resemble S. scrofa in their essential skull characters differ conspicuously from each other in other respects, as in the length of the ears and legs, curvature of the ribs, colour, hairiness, size and proportions of the body.

      The wild Sus scrofa has a wide range, namely, Europe, North Africa, as identified by osteological characters by Rutimeyer, and Hindostan, as similarly identified by Nathusius. But the wild boars inhabiting these several countries differ so much from each other in external characters, that they have been ranked by some naturalists as specifically distinct. Even within Hindostan these animals, according to Mr. Blyth, form very distinct races in the different districts; in the N. Western provinces, as I am informed by the Rev. R. Everest, the boar never exceeds 36 inches in height, whilst in Bengal one has been measured 44 inches in height. In Europe, Northern Africa, and Hindostan, domestic pigs have been known to cross with the wild native species (3/3. For Europe see Bechstein 'Naturgesch. Deutschlands' 1801 b. 1 s. 505. Several accounts have been published on the fertility of the offspring from wild and tame swine. See Burdach 'Physiology' and Godron 'De l'Espece' tome 1 page 370. For Africa 'Bull. de la Soc. d'Acclimat.' tome 4 page 389. For India see Nathusius 'Schweineschadel' s. 148.); and in Hindostan an accurate observer (3/4. Sir W. Elliot Catalogue of Mammalia 'Madras Journal of Lit. and Science' volume 10 page 219.), Sir Walter Elliot, after describing the differences between wild Indian and wild German boars, remarks that "the same differences are perceptible in the domesticated individuals of the two countries." We may therefore conclude that the breeds of the Sus scrofa type are descended from, or have been modified by crossing with, forms which may be ranked as geographical races, but which, according to some naturalists, ought to be ranked as distinct species.

      Pigs of the Sus indicus type are best known to Englishmen under the form of the Chinese breed. The skull of S. indicus, as described by Nathusius, differs from that of S. scrofa in several minor respects, as in its greater breadth and in some details in the teeth; but chiefly in the shortness of the lachrymal bones, in the greater width of the fore part of the palate- bones, and in the divergence of the premolar teeth. It deserves especial notice that these latter characters are not gained, even in the least degree, by the domesticated forms of S. scrofa. After reading the remarks and descriptions given by Nathusius, it seems to me to be merely playing with words to doubt whether S. indicus ought to be ranked as a species; for the above-specified differences are more strongly marked than any that can be pointed out between, for instance, the fox and the wolf, or the ass and the horse. As already stated, S. indicus is not known in a wild state; but its domesticated forms, according to Nathusius, come near to S. vittatus of Java and some allied species. A pig found wild in the Aru islands ('Schweineschadel' s. 169) is apparently identical with S. indicus; but it is doubtful whether this is a truly native animal. The domesticated breeds of China, Cochin-China, and Siam belong to this type. The Roman or Neapolitan breed, the Andalusian, the Hungarian, and the "Krause" swine of Nathusius, inhabiting south-eastern Europe and Turkey, and having fine curly hair, and the small Swiss "Bundtnerschwein" of Rutimeyer, all agree in their more important skull-characters with S. indicus, and, as is supposed, have all been largely crossed with this form. Pigs of this type have existed during a long period on the shores of the Mediterranean, for a figure ('Schweineschadel' s. 142) closely resembling the existing Neapolitan pig was found in the buried city of Herculaneum.

      Rutimeyer has made the remarkable discovery that there lived contemporaneously in Switzerland, during the Neolithic period, two domesticated forms, the S. scrofa, and the S. scrofa palustris or Torfschwein. Rutimeyer perceived that the latter approached the Eastern breeds, and, according to Nathusius, it certainly belongs to the S. indicus group; but Rutimeyer has subsequently shown that it differs in some well- marked characters. This author was formerly convinced that his Torfschwein existed as a wild animal during the first part of the Stone period, and was domesticated during a later part of the same period. (3/5. 'Pfahlbauten' s. 163 et passim.) Nathusius, whilst he fully admits the curious fact first observed by Rutimeyer, that the bones of domesticated and wild animals can be distinguished by their different aspect, yet, from special difficulties in the case of the bones of the pig ('Schweineschadel' s. 147), is not convinced of the truth of the above conclusion; and Rutimeyer himself seems now to feel some doubt. Other naturalists have also argued strongly on the same side as Nathusius. (3/6. See J.W. Schutz' interesting essay 'Zur Kenntniss des Torfschweins' 1868. This author believes that the Torfschwein is descended from a distinct species, the S. sennariensis of Central Africa.)

      Several breeds, differing in the proportions of the body, in the length of the ears, in the nature of the hair, in colour, etc., come under the S. indicus type. Nor is this surprising, considering how ancient the domestication of this form has been both in Europe and in China. In this latter country the date is believed by an eminent Chinese scholar (3/7. Stan. Julien quoted by de Blainville 'Osteographie' page 163.) to go back at least 4900 years from the present time. This same scholar alludes to the existence of many local varieties of the pig in China; and at the present time the Chinese take extraordinary pains in feeding and tending their pigs, not even allowing them to walk from place to place. (3/8. Richardson 'Pigs, their Origin' etc. page 26.) Hence these pigs, as Nathusius has remarked (3/9. 'Die Racen des Schweines' s. 47, 64.), display in an eminent degree the characters of a highly-cultivated race, and hence, no doubt, their high value in the improvement of our European breeds. Nathusius makes a remarkable statement ('Schweineschadel' s. 138), that the infusion of the 1/32nd, or even of the 1/64th, part of the blood of S. indicus into a breed of S. scrofa, is sufficient plainly to modify the skull of the latter species. This singular fact may perhaps be accounted for by several of the chief distinctive characters of S. indicus, such as the shortness of the lachrymal bones, etc., being common to several species of the genus; for in crosses characters which are common to many species apparently tend to be prepotent over those appertaining to only a few species.

      (FIGURE 2. HEAD OF JAPAN OR MASKED PIG. (Copied from Mr. Bartlett's paper in 'Proc. Zoolog. Soc.' 1861 page 263.))

      The Japan pig (S. pliciceps of Gray), which was formerly exhibited in the Zoological Gardens, has an extraordinary appearance from its short head, broad forehead and nose, great fleshy ears, and deeply furrowed skin. Figure 2 is copied from that given by Mr. Bartlett. (3/10. 'Proc. Zoolog. Soc.' 1861 page 263.) Not only is the face furrowed, but thick folds of skin, which are harder than the other parts, almost like the plates on the Indian rhinoceros, hang about the shoulders and rump. It is coloured black, with white feet, and breeds true. That it has long been domesticated there can be little doubt; and this might have been inferred even from the fact that its young are not longitudinally striped; for this is a character common to all the species included within the genus Sus and the allied genera whilst in their natural state. (3/11. Sclater in 'Proc. Zoolog. Soc.' February 26, 1861.) Dr. Gray (3/12. 'Proc. Zoolog. Soc.' 1862 page 13. The skull has since been described much more fully by Professor Lucae in a very interesting essay, 'Der Schadel des Maskenschweines' 1870. He confirms the conclusion of von Nathusius on the relationship of this kind of pig.) has described the skull of this animal, which he ranks not only as a distinct species, but places it in a distinct section of the genus. Nathusius, however, after his careful study of the whole group, states positively ('Schweineschadel' s. 153-158). that the skull in all essential characters closely resembles that of the short-eared Chinese breed of the S. indicus type. Hence Nathusius considers СКАЧАТЬ