COSMIC PHILOSOPHY 



For our present purpose, however, it is not 

 needful that we should be able to accomplish 

 the latter task, which would require a know- 

 ledge of the minutiae of the organic world such 

 as is not likely to be possessed by any one for 

 a long time to come. It is enough for us to 

 note that the ordinary process of competition, 

 among organisms as among dialects, tends to 

 kill out the means much sooner than the ex- 

 tremes. Still more clear will this become, if 

 we recur to one of the hypothetical illustrations 

 given in the preceding chapter. It was there 

 shown that, in the case of a group of ruminants 

 hitherto isolated from carnivorous foes, and in 

 which different strains or varieties have begun 

 to establish themselves, a newly arriving inci- 

 dent force, in the shape of strong and swift 

 carnivora, will at once tend to exterminate all 

 the intermediate forms, while the extremes will 

 not only be indefinitely preserved, but will be- 

 come yet more widely different from each other. 

 Now this hypothetical case is probably a fair 

 sample of a very large proportion — perhaps 

 the majority — of the cases in which specific 

 variations have been rapidly accumulated and 

 persistently fixed. It is by no means Hkely that 

 variation has gone on throughout the past with 

 a uniform pace ; but there must rather have 

 been immensely long periods of comparative 

 stability, alternating with relatively brief periods, 



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