60 " Natural Selection " 



"How?" — the cause of mutations; the survival of 

 mutations ; whether these are slow and progressive or 

 sudden and extensive. If natural selection is dis- 

 credited — and Dewar and Finn have relegated it to a 

 very inferior place in the evolutionary process — what 

 are the determining factors in evolution ? Within 

 the dawn of history, although we know of species 

 becoming extinct, do we know of a single new species 

 having arisen ? It is here open to any Darwinian 

 to say : " You admit that a species has become 

 extinct. How could that occur except through the 

 operation of "natural selection"? That question at 

 once takes us back to the Darwinian hypothesis, which 

 was founded upon the " struggle for existence " owing 

 to the excess of reproduction and the growth of the 

 species beyond the food supply. "It is the doctrine 

 of Malthus applied with manifold force to the whole 

 animal and vegetable kingdom," said Darwin. This 

 must never be forgotten. The excessive numbers had 

 to " struggle for existence." This brought about the 

 ' ' survival of the fittest . ' ' The struggle caused ' ' favour- 

 able mutations " to appear, these were perpetuated ; 

 new and stronger, swift or more cunning species arose, 

 and thus the method of evolution was proved. But 

 we know now that the excess of reproduction is never 

 allowed to reach the adult stage or to come into 

 competition for food with the rest of the species. 

 " The cannibal habit of the male " has regulated and 

 controlled the vast excess which nature has always in 

 reserve in order to replace any sudden or gradual 

 elimination of the parents which may be brought 

 about by famine, pestilence or hostile attack of any 

 kind. 



A species may become extinct through a hostile 

 environment. This was known long before Darwin's 

 day, and environment was the explanation given 



