Art and Science 



We should like to know, first, somewhere 

 about how much disuse was able to do after 

 all, and moreover why, if it can do anything 

 at all, it should not be able to do all. Mr. 

 Darwin says : " Any change in structure and 

 function which can be effected by small stages 

 is within the power of natural selection." 

 "And why not," we ask, "within the power 

 of use and disuse?" Moreover, on a later 

 page we find Mr. Darwin saying : 



" It appears probable that disuse has been the 

 main agent in rendering organs rudimentary 

 [italics mine]. It would at first lead by slow 

 steps to the more and more complete reduction 

 of a part, until at last it has become rudimentary 

 as in the case of the eyes of animals inhabit- 

 ing dark caverns, and of the wings of birds 

 inhabiting oceanic islands, which have seldom 

 been forced by beasts of prey to take flight, 

 and have ultimately lost the power of flying. 

 Again, an organ, useful under certain condi- 

 tions, might become injurious under others, as 

 with the wings of beetles living on small and 

 exposed islands ; and in this case natural selec- 

 tion will have aided in reducing the organ, 



267 



