VARIATION UNDER DOMESTICATION 33 



By a similar process of selection, and by careful train- 

 ing, the whole body of English racehorses have come to 

 surpass in fleetness and size the parent Arab stock, so 

 that the latter, by the regulations for the Goodwood Races, 

 are favoured in the weights they carry. Lord Spencer 

 and others have shown how the cattle of England have 

 increased in weight and in early maturity, compared with 

 the stock formerly kept in this country. By comparing 

 the accounts given in old pigeon treatises of carriers and 

 tumblers with these breeds as now existing in Britain, 

 India, and Persia, we can, I think, clearly trace the stages 

 through which they have insensibly passed, and come to 

 differ so greatly from the rock-pigeon. 



Youatt gives an excellent illustration of the effects of 

 a course of selection, which may be considered as un- 

 consciously followed, in so far that the breeders could 

 never have expected or even have wished to have pro- 

 duced the result which ensued — namely, the production 

 of two distinct strains. The two flocks of Leicester sheep 

 kept by Mr. Buckley and Mr. Burgess, as Mr. Youatt re- 

 marks, ' have been purely bred from the original stock of 

 Mr. Bakewell for upwards of fifty years. There is not 

 a suspicion existing in the mind of any one at all 

 acquainted with the subject that the owner of either of 

 them has deviated in any one instance from the pure 

 blood of Mr. Bakewell's flock, and yet the difference 

 between the sheep possessed by these two gentlemen is 

 so great that they have the appearance of being quite 

 different varieties.' 



If there exist savages so barbarous as never to think 

 of the inherited character of the offspring of their 

 domestic animals, yet any one animal particularly use- 

 ful to them, for any special purpose, would be carefully 

 preserved during famines and other accidents, to 

 which savages are so liable, and such choice animals 

 would thus generally leave more offspring than the 

 inferior ones ; so that in this case there would be a 

 kind of unconscious selection going on. We see 

 the value set on animals even by the barbarians of 

 Tierra del Fuego, by their killing and devouring their 



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