Chap. VIIL] IN DOMESTICATED ANIMALS. 329 



stroyed; so that habit and some - degree of selection 

 have probably concurred in civilising by inheritance 

 our dogs. On the other hand, young chickens have lost, 

 wholly by habit, that fear of the dog and cat which no 

 doubt was originally instinctive in them ; for I am in- 

 formed by Captain Hutton that the young chickens of 

 the parent-stock, the Gallus bankiva, when reared in 

 India under a hen, are at first excessively wild. So it 

 is with young pheasants reared in England under a hen. 

 It is not that chickens have lost all fear, but fear only 

 of dogs and cats, for if the hen gives the danger-chuckle, 

 they will run (more especially young turkeys) from 

 under her, and conceal themselves in the surrounding 

 grass or thickets ; and this is evidently done for the 

 instinctive purpose of allowing, as we see in wild ground- 

 birds, their mother to fly away. But this instinct re- 

 tained by our chickens has become useless under domesti- 

 cation, for the mother-hen has almost lost by disuse the 

 power of flight. 



Hence, we may conclude, that under domestication 

 instincts have been acquired, and natural instincts have 

 been lost, partly by habit, and partly by man selecting 

 and accumulating, during successive generations, peculiar 

 mental habits and actions, which at first appeared from 

 what we must in our ignorance call an accident. In 

 some cases compulsory habit alone has sufficed to 

 produce inherited mental changes ; in other cases, 

 compulsory habit has done nothing, and all has been 

 the result of selection, pursued both methodically and 

 unconsciously : but in most cases habit and selection 

 have probably concurred. 



