CHAPTER XXXIX 

 DIVERGENCE AND ADAPTATION 



The continued modification of organisms by the agency 

 of natural selection tends to adapt them to diverse kinds 

 of environment. The struggle for existence is most 

 severe between animals occupying the same region and 

 living on the same kind of food. There is little competi- 

 tion between the grasshopper, the honey bee and the house 

 fly, because they do not interfere much with one another's 

 activities. In a small town there is competition between 

 rival grocery stores, but comparatively little between the 

 grocery man and the blacksmith. It is advantageous for 

 organisms as it is for, tradesmen to get their living in 

 different ways; there is a certain escape from the rigors 

 of the struggle for existence. Any organism which adopts 

 a new mode of life or is able to subsist upon a different kind 

 of food secures a certain advantage over its neighbors. As 

 a result of this, natural selection is ever working toward 

 the production of diversity; it tends to fill with a living 

 organism all situations in nature which can support an 

 inhabitant. In looking over the world one cannot avoid 

 a feeling of wonder and surprise that Nature has filled so 

 many different kinds of situations with living beings. 

 She has adapted them to the severe cold of the arctic 

 regions, to the blistering heat of arid deserts, to the depths 

 of the oceans where many forms live in a region of cold 

 and darkness under a pressure of several miles of water. 

 She has modified them often into the most fantastic 



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