POST-DARWINIAN VIEWS 6^ 



lishing the new variety. Finally there is the objection 

 that evolution by the selection of continuous variations 

 ought to result in producing a continuous series of 

 organisms; whereas it is found to produce independent 

 species with intervening gaps. The missing links are 

 as numerous as are the distinct species that have 

 appeared on this planet. 



Objections have been raised to the main contention 

 of Darwin that natural selection is the chief factor of 

 the evolution of species. It has become widely acknowl- 

 edged that natural selection is not a positive cause of 

 evolution at all. Its function is to eliminate unfit 

 products of evolution, to clear its pathway of obstruc- 

 tions, and to determine what products shall persist. 

 The cause or causes of variation and development are 

 elsewhere to be sought.^ The analogy alleged to exist 

 between artificial and natural selection has been pressed 

 too far. Intelligent control is an essential factor in 

 artificial selection, a factor which Darwinists ignore. 

 It depends also upon a completeness of isolation which 

 nature does not often afford when needed for the opera- 

 tion of natural selection. It does not produce stable 

 species, but varieties which usually revert to ancestral 

 type when left uncontrolled, whereas the results of 

 natural evolution persist. Other differences might be 

 mentioned, the most important being that, whereas 

 artificial selection has never produced indubitable 

 species, mutually non-fertile, nature has done so in a 

 multitude of instances. Obviously determinative fac- 



J Darwin did not claim to explain variations, but survivals. 



