WAYS OF NATURE 



We are not warranted in attributing to any wild, 

 untrained animal a degree of intelligence that its 

 forbears could not have possessed. The animals 

 for the most part act upon inherited knowledge, that 

 is, knowledge that does not depend upon instruction 

 or experience. For instance, the red squirrels near 

 me seem to know that chestnut-burs will open if cut 

 from the tree and allowed to lie upon the ground. At 

 least, they act upon this theory. I do not suppose 

 this fact or knowledge hes in the squirrel's mind as 

 it would in that of a man — as a deduction from 

 facts of experience or of observation. The squirrel 

 cuts off the chestnuts because he is hungry for them, 

 and because his ancestors for long generations have 

 cut them off in the same way. That the air or sun 

 will cause the burs to open is a bit of knowledge that 

 I do not suppose he possesses in the sense in which 

 we possess it: he is in a hurry for the nuts, and 

 does not by any means always wait for the burs to 

 open ; he frequently chips them up and eats the pale 

 nuts. 



The same squirrel will bite into the limbs of a 

 maple tree in spring and suck the sap. What does 

 he know about maple trees and the spring flow of 

 sap ? Nothing as a mental concept, as a bit of con- 

 crete knowledge. He often finds the sap flowing 

 from a crack or other wound in the limbs of a maple, 

 and he sips it and likes it. Then he sinks his teeth 

 into the limb, as his forbears undoubtedly did. 

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