A Story Outline of Evolution 



of the extermination of all life in a short time if it were not 

 for the balance brought about by the birds. Many of these 

 birds turn these harmful insects into an agency of food for 

 man. As we use the stored energy of dinosaur and flying 

 crocodile in our automobiles, so likewise when we sit down 

 to a chicken or turkey dinner, it Is a la bug, worm and grass- 

 hopper, our enemies transformed, that we are eating. 



Nature has developed the form of each group so that it 

 is best fitted to secure the food It eats with the least effort. 

 Every part of the entire form Is adapted for a specific pur- 

 pose. Every wing, neck, bill, foot, leg and feather are 

 adapted to some particular function. The swimmers are 

 endowed with webfeet, the waders with long legs and long 

 bills, the fish eaters with sharp claws and hooked bills and 

 their colors are usually developed to match the colors of 

 their surroundings as a protection against their enemies. 

 Their ancestral tails have been drawn up Into a little knob 

 yet containing an atrophied vertebra which furnishes a flexi- 

 ble tail rudder in their flight. But some of these families 

 found places where food could be secured with little effort. 

 Some of their body organs that had been developed as a 

 matter of necessity In their struggle for food were no longer 

 needed and no longer used. Nature demands action of its 

 creatures and unless action continues, she sets up processes 

 of destruction whose purpose is to destroy the Inactive part, 

 for nothing In Nature Is constant. All life Is either advanc- 

 ing or retreating. Because of a change of food In some of 

 the birds or because of its abundance, they quit the use of 

 wings and as a consequence. Nature began to tear down and 



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