NATURAL SELECTION 67 



possessors ; for, as Darwin says, " We may feel sure 

 that any variation, in the least degree injurious, would 

 be rigidly destroyed ; " third, those variations that are 

 indifferent, being neither advantageous nor injurious. 

 We naturally ask, What occasion had Darwin to create 

 the injurious variation ? If slight advantageous 

 variations give their possessors such superiority over 

 the others that they survive, while all the individuals 

 that have less fortunate variations perish, what office 

 or function is left for injurious variations to discharge 

 as eliminating factors that is not equally well dis- 

 charged by variations slightly inferior to those which 

 give to their possessors survival in the struggle for 

 existence ? 



Again, when we look to the concrete, or to the 

 actual facts of existence, there does not appear to 

 be any destruction that can be called " rigid " of 

 bad variations. If in a section of an Indian jungle, 

 which contains an average population of 100 pairs 

 of adult tigers, 2100 young are born in each genera- 

 tion, of whom 1900 perish, do all these 1900, or 

 only a part of them, perish from possessing such 

 injurious variations as Nature rigidly destroys ? 



It matters not what the proportion is, for the 

 result in successive generations is always the same, 

 namely, that 1900 perish. The possessors of in- 

 jurious variations are in each generation rigidly 

 destroyed, but in each generation there are as many 

 injurious variations as were in the generation before 

 it, and as will be in the generation after it. What 



