Criticism of Natural Selection 143 



creatures — a parable for man's instruction. Some- 

 what different from the environmental sieve in gen- 

 eral is that which is furnished by the inter-relations 

 established between living creatures in the web of life. 

 The system of linkages tends to become more and 

 more intricate from age to age; it is often subtle 

 enough to discriminate between Shibboleth and Sib- 

 boleth ; it is stable enough, as in the inter-dependence 

 of flowers and their insect visitors, to serve as an 

 external security for progress. Along this line is 

 Man's great opportunity. 



RECENT CRITICISM 



We do not share the view, often expressed in recent 

 years, that Darwin's theory of Natural Selection has 

 become outworn. If mutations have been common 

 throughout the evolution-process, if a new position of 

 organic stability has often been reached suddenly, 

 if the Proteus has frequently been leaping as well as 

 creeping, then the burden that the theory of Natural 

 Selection has had to bear will be less than Darwin 

 believed; but even De Vries, one of the founders of 

 the "Mutation-Theory," declares that sifting must 

 still be regarded as essential. "The origin of new 

 species, which is in part the effect of mutability, is, 

 however, due mainly to natural selection. Mutability 

 provides the new characters and new elementary 

 species. Natural selection, oh the other hand, decides 

 what is to live and what is to die." (Seward's Darwin 

 and Modern Science, Cambridge, 1909, p. 77.) 



Critics of Darwinism have in recent years made 



