THEORIES AND MECHANISM OF EVOLUTION 



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ceeding generation of this animal the ant- 

 lers became larger and more complex until 

 they became so fantastic that it is difficult 

 to understand how the animal could man- 

 age them at all. It must have required much 

 of the elk's metabolic output to supply ma- 

 terials for their construction, to say nothing 

 of the burden of supporting them. Here is 

 a case of progressive adaptation for a struc- 

 ture which had decided survival value 

 when it first appeared, but which even- 

 tually became a factor, itself, in eliminating 

 the species. However, our information is 

 not complete and one must be cautious 

 in drawing conclusions because other fac- 

 tors in its environment may have been 

 equally important. For example, a sudden 

 increase in wolves or a virulent disease. 



in addition to its cumbersome antlers, could 

 have hastened the departure of this beau- 

 tiful animal. 



EVOLUTION AND THE FUTURE 



Some believe that evolution has run its 

 course and that all of the niches of the 

 world have been filled so that no further 

 change is possible. Furthermore, others 

 contend that the ultimate goal of evolution, 

 namely, man, has been attained and there 

 is now no "place to go." One might be 

 inclined to agree with these contentions if 

 there were no evidence of evolution goino- 

 on around us and if man had become per- 

 fect in every respect, leaving no room for 

 improvement. Most of us would not sub- 



