ARTIFICIAL SELECTION 



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At Chillenham, in England, is still preserved a herd of the 

 original wild white English cattle, from which most or all of the 

 British breeds are said to be descended. It is stated that Lord 

 Cawdor has offered to reproduce this herd, by selection alone, in 

 three or four generations, using the relatively primitive Welsh 

 cattle as his base of operations. 



In general, those characters which are usually affected by 

 selection, whether natural or artificial, are characters of degree. 

 They are matters of more or less, a greater or less degree of 

 strength, swiftness, size, endurance, fertility, capacity to lay 



FIG. 51. Typical American merino ewe, a highly specialized breed with fine close-set 



wool. (After Shaw.) 



on fat, docility, intelligence, or of whatever it may be. Under 

 ordinary conditions these characters selected are not traits of 

 quality. They do not represent a new thing, a new acquisition, 

 but a different degree of development of an old one, or, at most, 

 a change in their relative arrangement, an alteration of bio- 

 logical perspective. 



The characters which distinguish true breeds as well as true 

 species are not of this order. They are in their essence quali- 

 tative and not quantitative. They are not, as a rule, adaptive. 

 One set of species or race traits is as good as another, if the good 

 qualities or adaptive qualities are represented in an equally 

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