The Struggle for Existence 



existence, as many of the statements contained 

 in recent books on evolution seem to us to be 

 based upon a mistaken conception of this 

 important factor. 



As usual, Darwin's disciples have failed to 

 improve upon the account he gave of the nature 

 of the struggle for existence. This is set forth in 

 Chapter III. of the Origin of Species. 



" The causes," writes Darwin (new edition, 

 p. 83), " which check the natural tendency of 

 each species to increase in number are most 

 obscure. Look at the most vigorous species ; 

 by as much as it swarms in numbers, by so much 

 will it tend to increase still further. We know 

 not exactly what the checks are even in a single 

 instance." This is perfectly true. Nevertheless 

 elaborate theories of protective and warning 

 colouration and mimicry have been built up on 

 the tacit assumption that the checks to the multi- 

 plication of all, or nearly all, species are the 

 creatures which prey upon them. Possibly no 

 Wallaceian asserts this in so many words, but it 

 is a logical deduction from the excessive pro- 

 minence each one gives to the various theories of 

 animal colouration ; for, if the chief foes of an 

 organism are not the creatures which prey upon 

 it, how can the particular shade and pattern of 

 its coat be of such paramount importance to it ? 



We shall endeavour to show that there are 

 checks on the increase of a species far more 



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