58 NATURAL SET jECTION r CHAp 



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and do occur under nature. Lei it algo be borne in mind ^ w 

 infinitely complex and close-fitting are the mutua i relations of all 

 organic beings to each other jfoft to ^ e ^ r physical conditions of 

 life ; and consequently whaV^ifinitely varied diversities of structure 

 might be ( o 3gffo each being under changing conditions of life. 

 Car?* i^' 'then, be thought improbable, seeing that variations useful 

 to/ man have undoubtedly occurred, that other variations useful 

 in some way to each being in the great and complex battle of life, 

 should occur in the course of many successive generations 1 If 

 such do occur, can we doubt (remembering that many more 

 individuals are born than can possibly survive) that individuals 

 having any advantage, however slight, over others, would have 

 the best chance of surviving and of procreating their kind ? On 

 the other hand, we may feel sure that any variation in the least 

 degree injurious would be rigidly destroyed. This preservation 

 of favourable individual differences and variations, and the 

 destruction of those which are injurious, I have called Natural 

 Selection, or the Survival of the Fittest. Variations neither useful 

 nor injurious would not be affected by natural selection, and 

 would be left either a fluctuating element, as perhaps we see in 

 certain polymorphic species, or would ultimately become fixed, 

 owing to the nature of the organism and the nature of the 

 conditions. 



Several writers have misapprehended or objected to the term 

 Natural Selection. Some have even imagined that natural 

 selection induces variability, whereas it implies only the preserva- 

 tion of such variations as arise and are beneficial to the being 

 under its conditions of life. No one objects to agriculturists 

 speaking of the potent effects of man's selection ; and in this case 

 the individual differences given by nature, which man for some 

 object selects, must of necessity first occur. Others have objected 

 that the term selection implies conscious choice in the animals 

 which become modified ; and it has even been urged that, as 

 plants have no volition, natural selection is not applicable to 

 them ! In the literal sense of the word, no doubt, natural selection 

 is a false term ; but who ever objected to chemists speaking of 

 the elective affinities of the various elements ? and yet an acid 

 cannot strictly be said to elect the base with which it in preference 

 combines. It has been said that I speak of natural selection as 



-p an active power or Deity ; but who objects to an author speaking- 

 of the attraction of gravity as ruling the movements of the 

 planets ? Every one knows what is meant and is implied by such 

 metaphorical expressions ; and they are almost necessary for 

 brevity. So again it is difficult to avoid personifying the word 

 Nature ; but I mean by Nature, only the aggregate action and 



'' product of many natural laws, and by laws the sequence of events 



