.^^' 



EVOLUTION AND HUMAN DESTINY 



source of energy available to animal life which poten- 

 tially can be useful for purposes other than the mere 

 building of structure. Such energy can be used for mo- 

 tive power. The ability to make use of energy derived 

 from decreasing of the complexity of other matter is 

 of great importance in the development of animal 

 life. It is interesting to note that as evolution gives 

 rise to more complex creatures, the complexity of the 

 necessary building materials which can no longer be 

 synthesized and must consequently be obtained from 

 other life, also increases. 



At the present time not very much appears to be 

 known about the transition from the essentially 

 molecular viruses to cellular organisms. However, it 

 is known that many grades of complexity exist among 

 / present day viruses. One of the simplest, the tobacco- 

 mosaic, appears to be little else than a reproducing 

 ^ protein molecule. A complex one, like that of vaccinia, 

 ''approaches the size of some cellular organisms and 

 contains a variety of different substances. A group of 

 organisms, known as rickettsiae, may be an interme- 

 diate form. They appear to be organisms which con- 

 sist of more than one molecule, but are not yet in- 

 tegrated into a cellular pattern. 



THE CELL A NEW ENTITY OF HIGHER ORGANIZATION 



Of greater significance than the understanding of 

 the actual mechanism by means of which the evolution 



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