A BEAVER S REASON 



and flexibility of instinct which all animals show, 

 some more and some less, is not reason, though it 

 is doubtless the first step toward it. Out of it the 

 conscious reason and intelligence of man probably 

 have been evolved. I do not object to hearing this 

 variability and plasticity of instinct called the twi 

 light of mind or rudimentary mentality. It is that, 

 or something like that. What I object to is hearing 

 those things in animal life ascribed to reason that 

 can be easier accounted for on the theory of instinct. 

 I must differ from the ornithologist of the New 

 York Zoological Park when he says in a recent 

 paper that a bird s affection for her young is not 

 an instinct, an uncontrollable emotion, but I quite 

 agree with him that it does not differ, in kind at 

 least, from the emotion of the human mother. In 

 both cases the affection is instinctive, and not a 

 matter of reason, or forethought, or afterthought at 

 all. The two affections differ in this: that one is 

 brief and transient, and the other is deep and last 

 ing. Under stress of circumstances the bird will 

 abandon her helpless young, while the human 

 mother will not. When the food supply fails, the 

 lower animal will not share the last morsel with its 

 young ; its fierce hunger makes it forget them. Dur 

 ing the cold, wet summer of 1903 a vast number of 

 half -fledged birds orioles, finches, warblers per 

 ished in the nest, probably from scarcity of insect 

 food and the neglect of the mothers to hover them. 

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