424 CHARLES DARWIN 



at Tristan d'Acunha in the Atlantic, Carmichael* states that 

 the only two land-birds, a thrush and a bunting, were " so 

 tame as to suffer themselves to be caught with a hand-net." 

 From these several facts we may, I think, conclude, first, that 

 the wildness of birds with regard to man, is a particular 

 instinct directed against him, and not dependent upon any 

 general degree of caution arising from other sources of 

 danger; secondly, that it is not acquired by individual birds 

 in a short time, even when much persecuted; but that in the 

 course of successive generations it becomes hereditary. With 

 domesticated animals we are accustomed to see new mental 

 habits or instincts acquired or rendered hereditary; but with 

 animals in a state of nature, it must always be most difficult 

 to discover instances of acquired hereditary knowledge. In 

 regard to the wildness of birds towards man, there is no way 

 of accounting for it, except as an inherited habit: compara- 

 tively few young birds, in any one year, have been injured 

 by man in England, yet almost all, even nestlings, are afraid 

 of him; many individuals, on the other hand, both at the 

 Galapagos and at the Falklands, have been pursued and 

 injured by man, yet have not learned a salutary dread of 

 him. We may infer from these facts, what havoc the intro- 

 duction of any new beast of prey must cause in a country, 

 before the instincts of the indigenous inhabitants have 

 become adapted to the stranger's craft or power. 



6 Linn. Trans., vol. xii. p. 496. The most anomalous fact on this sub- 

 ject which I have met with is the wildness of the small birds in the Arctic 

 parts of North America (as described by Richardson, Fauna Bor., vol. ii. 

 P- 332). where they are said never to be persecuted. This case is the more 

 strange, because it is asserted that some of the same species in their winter- 

 quarters in the United States are tame. There is much, as Dr. Richardson 

 well remarks, utterly inexplicable connected with the different degrees of 

 shyness and care with which birds conceal their nests. How strange it 

 is that the English wood-pigeon, generally so wild a bird, should very fre 

 quently rear its young in shrubberies close to houses 1 



