THE KEY TO ANIMAL BEHAVIOR 



impulse unless we train it to do so or drill it into 

 new habits. A man has an impulse to steal or to 

 murder, to over-eat or to run away from danger; 

 but he checks the impulse, because he is a man and 

 not a dog. 



Each animal species inherits an organization that 

 determines the kind of life it shall live, how it shall 

 meet its enemies, how get its food and what that 

 food shall be, its habitat, and the like, and it in- 

 herits the instincts that go with the organization. 

 The porcupine knows how to use its quills, the 

 skunk its essence, the hawk its talons, the cuttle- 

 fish its ink, without previous experience or instruc- 

 tion — that is, instinctively. The mole takes to the 

 ground and is lost on the surface. His organization 

 makes him a prisoner of the soil. Call his behavior 

 instinctive or a tropism or what you will, it is innate, 

 and is not a habit acquired by the individual mole, 

 but by the race of moles. 



Man's organization is not specialized in any- 

 thing like the same degree as that of his animal kin. 

 He inherits no weapons, either of offense or defense; 

 he is confined to no habitat or clime; he is restricted 

 to no special food. He is a tool-maker and inventor, 

 and arms and equips himself with a thousand ex- 

 ternal things and forces. He is a learner, an ac- 

 quirer of knowledge. He has legs with which to 

 walk, but he has to learn to walk as much as he has 

 to learn to skate or to swim or to ride a bicycle. He 

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