234 SPECIAL INSTINCTS. 



require to be taught not to attack poultry, sheep, and pigs! 

 No doubt they occasionally do make an attack, and are then 

 beaten ; and if not cured, they are destroyed ; so that habit 

 and some degree of selection have probably concurred in 

 civilizing 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 informed 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 clanger 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 pur- 

 pose of allowing, as we see in wild ground-birds, their 

 mother to fly away. But this instinct retained by our 

 chickens has become useless under domestication, for the 

 mother hen has almost lost by disuse the power of flight. 



Hence, we may conclude that under domestication in- 

 stincts have been acquired and natural instincts have been 

 lost, partly by habit and partly by man selecting and accu- 

 mulating, 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. 



SPECIAL INSTINCTS. 



We shall, perhaps, best understand how instincts in a 

 state of nature have become modified by selection, by con- 

 sidering a few cases. I will select only three, namely, the 

 instinct which leads the cuckoo to lay her eggs in other birds' 

 nests ; the slave-making instinct of certain ants ; and the 

 cell-making power of the hive-bee. These two latter instincts 

 have generally and justly been ranked by naturalists as the 

 most wonderful of all known instincts. 



