CHAPTER III 



BREEDS OF SWINE 



Swine are plastic. — l"he life history of every species of 

 animal forms a more or less distinct arc, which may cover 

 a period of a hundred thousand or even a million years. 

 Species of animals are stable or plastic, depending on 

 their relative position on the arc of the life history of the 

 species. The nearer the species is to the starting point 

 of the arc, or, in other words, the younger the species, 

 the more plastic it is. At first a species is quite plastic 

 and variations abound, and progress in breeding, whether 

 it be natural or artificial, is very rapid and easy. Later, 

 the inherent tendencies of the species carry it along in 

 certain directions, and after a certain time the charac- 

 teristics may become so fixed that the species may not 

 be able to become harmonized with its surroundings, and 

 the result is the extinction of the race or species. The 

 swine species is, comparatively' speaking, near the be- 

 ginning of its arc of development. It is quite plastic and 

 variations are numerous. Breeding progre^^s is com- 

 paratively easy in the hands of man. Wild swine are 

 much more constant in characteristics than are domestic 

 swine, for in the wild state mutations not in accord with 

 nature are at once eliminated. Under domestication, all 

 sorts of variations and mutations have been preserved 

 and modified, and the result is that we have many types 

 of domesticated swine that are not in harmony with their 

 surroundings, which, of course, means ultimate loss. 

 Therefore, we might conclude, that, for instance, as com- 

 pared with horses, the formation and molding of breeds 



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