TIME AND CHANGE 



generalized organization has many chances. Man 

 is one of the most generalized of animals; no special 

 tools, no special weapons — his hand many tools and 

 weapons in one. Hence he is the most adaptable 

 of animals; all climes, all foods, all places are his; he 

 is master of the land, of the sea, of the air. 



Animal life is often curiously interdependent. I 

 asked our guide in the Adirondacks if there were 

 any ravens there. "Not nearly as many as there 

 used to be," he said, and his explanation of their 

 disappearance seems thoroughly scientific; it was 

 that the wolves and the panthers kept them in meat, 

 and now that these animals had disappeared, the 

 ravens had little to feed upon. If the moose were 

 compelled to graze from off the ground, like a sheep 

 or a cow, the species would probably soon become 

 extinct. Osborn thinks it probable that the huge 

 beast called titanothere finally became extinct early 

 in Tertiary times owing to the form of its teeth, 

 which were of such a type that they could not 

 change to meet a change in the flora upon which the 

 creature fed. Of course we shall never know what 

 narrow escapes our race had from extinction in the 

 remote past; some forms have ended in a blind alley, 

 like the sea-urchin and the oyster. Arthropoda have 

 continued to evolve and have reached their high- 

 water mark of intelligence in bees and ants. The 

 vertebrates went forward and have culminated in 

 man. Bergson thinks that in the vertebrates intel- 



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