WAYS OF NATURE 



The Baltimore oriole makes free use of strings in 

 its nest-building, and the songs of difPerent birds of 

 this species vary greatly, while the orchard oriole 

 makes no use of strings, so far as I have observed, 

 and its song is always and everywhere the same. 

 Hence we may say that the Uves of some birds run 

 much more in ruts than do those of others ; they 

 show less plasticity of instinct, and are perhaps for 

 that reason less near the state of free intelhgence. 



Organic life in all its forms is flexible; instinct is 

 flexible; the habits of aU the animals change more 

 or less with changed conditions, but the range of the 

 fluctuations in the lives of the wild creatures is very 

 limited, and is always determined by surrounding 

 circumstances, and not by individual volition, as it 

 so often is in the case of man. In a treeless country 

 birds that sing on the perch elsewhere wiU sing on 

 the wing. The black bear in the Southern States 

 " holes up " for a much shorter period than in Can- 

 ada or the Rockies. Why is the spruce grouse so 

 stupid compared with most other species ? Why is 

 the Canada jay so tame and familiar about your 

 camp in thie northern woods or in the Rockies, and 

 the other jays so wary ? Such variations, of course, 

 have their natural explanation, whatever it may be. 

 In New Zealand there is a parrot, the kea, that once 

 lived upon honey and fruit, but that now lives upon 

 the sheep, tearing its way down to the kidney fat. 



This is a wide departure in instinct, but it is not 

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