40 SELECTION BY MAN. Chap, h 



most fleeting of characters, have lately been exhibited 

 as distinct at our poultry-shows. 



I think these views further explain what has sometimes 

 been noticed — namely, that we know nothing about the 

 origin or history of any of our domestic breeds. But, in 

 fact, a breed, like a dialect of a language, can hardly be 

 said to have had a definite origin. A man preserves and 

 breeds from an individual with some slight deviation of 

 structure, or takes more care than usual in matching his 

 best animals and thus improves them, and the improved 

 individuals slowly spread in the immediate neighbour- 

 hood. But as yet they will hardly have a distinct name, 

 and from being only slightly valued, their history will 

 be disregarded. When further improved by the same 

 slow and gradual process, they will spread more widely, 

 and will get recognised as something distinct and valu- 

 able, and will then probably first receive a provincial 

 name. In semi-civilised countries, with little free com- 

 munication, the spreading and knowledge of any new 

 sub-breed will be a slow process. As soon as the points of 

 value of the new sub-breed are once fully acknowledged, 

 the principle, as I have called it, of unconscious selection 

 will always tend, — perhaps more at one period than at 

 another, as the breed rises or falls in fashion, — perhaps 

 more in one district than in another, according to the 

 state of civilisation of the inhabitants, — slowly to add to 

 the characteristic features of the breed, whatever they 

 may be. But the chance will be infinitely small of any 

 record having been preserved of such slow, varying, and 

 insensible changes. 



I must now say a few words on the circumstances, 

 favourable, or the reverse, to man's power of selection. 

 A high degree of variability is obviously favourable, 

 as freely giving the materials for selection to work 

 on ; not that mere individual differences are not amply 



