Origin of the Fittest 



subjects the marks are gained. So is it in nature. 

 Natural selection takes an organism as a whole. 

 One species may have established itself because 

 of its fleetness, a second because of its courage, 

 a third because it has a strong constitution, a 

 fourth because it is protectively coloured, a fifth 

 because it has good digestive powers, and so on. 



We thus perceive the part played by natural 

 selection and other forms of isolation in the 

 making of species. It is obvious that these 

 do not make species any more than the Civil 

 Service Commissioners manufacture Indian civil 

 servants. 



The real makers of species are the inherent 

 properties of protoplasm and the laws of variation 

 and heredity. These determine the nature of the 

 organism ; natural selection and the like factors 

 merely decide for each particular organism whether 

 it shall survive and give rise to a species. 



The way in which natural selection does its 

 work is comparatively easy to understand. But 

 this is only the fringe of the territory which we 

 call evolution. 



We seem to be tolerably near a solution of 

 the problem of the causes of the survival of 

 any particular mutation. This, however, is 

 merely a side issue. The real problem is the 

 cause of variations and mutations, or, in other 

 words, how species originate. At present our 

 knowledge of the causes of variation and muta- 



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