PIGS. 
43i 
to the European wild boar, and the other more resembling some of the Asiatic 
kinds. The late Professor Rolleston failed, however, to detect evidence of Asiatic 
affinity in any of the prehistoric swine of Europe, and accordingly came to the 
conclusion that they were all probably derived from the European wild species, 
although these might possibly have some crossing with an Asiatic stock. It must 
be confessed that this view is, at first sight, the most probable; and that the 
original domesticated races of different parts of the world have been derived from 
the wild species inhabiting the same districts. This is the opinion of Mr. Blanford, 
who states that the tame pig of India is doubtless derived from the wild S. 
cristatus, with which it probably interbreeds. In modern times, however, there has 
certainly been a great amount of intercrossing between the various breeds of 
domestic swine; and many of the races now most esteemed in Europe have a large 
proportion of Asiatic blood in their veins. 
The effects of domestication have been very marked on the swine, although 
the degree of variation from the wild type depends largely upon the amount of care 
that has been bestowed upon the breed. We have already mentioned that the 
European domestic breed differs from all wild species by the concave profile of the 
face; while as a rule domesticated races have uniformly-coloured young. Indeed, 
whenever the young of domestic swine are striped, a recent crossing with a wild 
race may not unreasonably be suspected. When domesticated pigs revert to a 
wild condition, the striping of the young is, however, frequently resumed. 
Domestication invariably greatly reduces the size of the tusks of the boars, which 
in some breeds are very small indeed; and in this respect we have a reversion to 
extinct species of swine, in the earlier forms of which the tusks were but slightly 
developed. There are also modifications in the form of the hinder part of the 
skull, in the number of joints in the backbone,' and in the length of the intestines. 
Equally marked differences obtain in the shape of the ears, which in some of the 
inferior breeds are large, flapping, and pendent, while in the superior breeds they 
are small and erect. As regards bodily form, we have but to contrast the long- 
legged, large-headed, and thin-bodied “ greyhound pig ” of Ireland, with some of 
the best modern breeds, like the Harrison swine represented on p. 430, to see how 
enormous is the difference in this respect. Darwin remarks, however, that the 
observations of Professor Nathusius tend to show “that the peculiar form of the 
skull and body in the most highly-cultivated races is not characteristic of any one 
race, but is common to all when improved up to the same standard. Thus the 
large-bodied, long-eared English breed with a convex back, and the small-bodied, 
short-eared, Chinese breeds with a concave back, when bred to the same state of 
perfection, nearly resemble each other in the form of the head and body. This 
result, it appears, is partly due to similar causes of change acting on the several 
races, and partly to man breeding the pig for one sole purpose, namely, for the 
greatest amount of flesh and fat; so that selection has always tended towards one 
and the same end. With most domestic animals the result of selection has been 
divergence of character, here it has been convergence.” 
Domesticated pigs are now found over the greater part of the habitable world; 
but while those kept in more northern regions are generally confined more or less 
closely to the homestead, the races of the warmer parts of the world are allowed to 
