Chap. VIll.J CHANGES OF HABIT OH INSTINCT. 325 



inhabit desert islands; and we see an instance of this 

 even in England, in the greater wildness of all our large 

 birds in comparison with our small birds; for the large 

 birds have been most persecuted by man. "We may 

 safely attribute the greater wildness of our large birds 

 to this cause; for in uninhabited islands large birds 

 are not more fearful than small; and the magpie, so wary 

 in England, is tame in Norway, as is the hooded crow in 

 Egypt. 



That the mental qualities of animals of the same 

 kind, born in a state of nature, vary much, could be 

 shown by many facts. Several cases could also be ad- 

 duced of occasional and strange habits in wild animals, 

 which, if advantageous to the species, might have given 

 rise, through natural selection, to new instincts. But 

 I am well aware that these general statements, without 

 the facts in detail, will produce but a feeble effect on the 

 reader's mind. I can only repeat my assurance, that I 

 do not speak without good evidence. 



Inherited Changes of Habit or Instinct in Domesticated 

 Animals. 



The possibility, or even probability, of inherited 

 variations of instinct in a state of nature will be strength- 

 ened by briefly considering a few cases under domesti- 

 cation. We shall thus be enabled to see the part which 

 habit and the selection of so-called spontaneous varia- 

 tions have played in modifying the mental qualities of 

 our domestic animals. It is i;otorious how much domes- 

 tic animals vary in their mental qualities. With eats, 

 for instance, one naturally takes to catching rats, and 

 another mice, and these tendencies are known to be in- 



