CHAPTER XI 



THE opinion that groups arise from mutants is opposed 

 to the theory of Natural Selection. We know this from 

 a passage, already quoted (page 2), in which Darwin 

 states that a species arising from a sport would arise 

 independently of selection. It is sometimes said, that 

 all experienced biologists regard selection as the principal 

 cause of evolution and adaptation, but that all are not 

 yet agreed as to the method of evolution, some believing 

 it to be a gradual process, others that it proceeds by 

 obvious steps. It is evident, however, that if imper- 

 ceptible gradation is an essential condition of evolution 

 by selection, such a statement is erroneous. If species 

 arise directly from mutants, they arise independently of 

 Natural Selection, as that process was imagined and 

 described by Darwin. 



The term Natural Selection does not call to mind the 

 same idea in all persons. It may be used like the word 

 competition, to express the fact that some organisms 

 succeed while others fail. We can often see that the 

 success of one kind of animal is accompanied by the 

 failure of another or of others. We see this so frequently 

 that we may regard success and failure together as one 

 of the primary processes of life, and if we wish, we may 

 speak of this process as Natural Selection. From this 

 point of view selection appears to be one process just as 



