Divergence of Character 



that in the course of evolution, species have 

 not been transmuted in linear series instead of 

 ramifying into branches ? This ramification of 

 a species into branches has been termed by 

 Romanes polytypic evolution. It is easy to see 

 how natural selection can bring about monotypic 

 evolution, but how can it have effected polytypic 

 evolution ? To use Darwin's phraseology, how 

 is it that divergence of character has come about ? 

 Darwin's reply to this question is (Origin of 

 Species, p. 1 36), "from the simple circumstance that 

 the more diversified the descendants from any 

 one species become in structure, constitution, and 

 habits, by so much will they be better enabled to 

 seize on many and widely diversified places in the 

 polity of nature, and so be enabled to increase in 

 numbers. 



" We can clearly discern this in the case of 

 animals with simple habits. Take the case of a 

 carnivorous quadruped, of which the number that 

 can be supported in any country has long ago 

 arrived at its full average. If its natural power 

 of increase be allowed to act, it can succeed in 

 increasing (the country not undergoing any 

 change in its conditions) only by its varying 

 descendants seizing on places at present occupied 

 by other animals : some of them, for instance, 

 being enabled to feed on new kinds of prey, 

 either dead or alive ; some inhabiting new 

 stations, climbing trees, frequenting water, and 



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