2o6 CAUSES OF VARIATION 



In this view of the case characters bad and good develop 

 together. The worst ones are eliminated, but many undesirable 

 or indifferent ones are left behind as not being sufficient to turn 

 the scale against the individual or the race. Thus many undesir- 

 able characters linger in all races, and, what is more to the point, 

 utility is not the cause of either the origin or the persistence of 

 characters, but only of their obliteration when sufficiently detri- 

 mental to destroy the individual and therefore cut off descent in 

 that particular line. 



The writer shares the opinion that this is the true limit of the 

 selection process under nature, and that the presence of unfavor- 

 able characters argues for their having arisen from causes quite 

 independent of selection. 



In our yards and fields we control selection according to what- 

 ever standards we may please to establish, but if unfavorable char- 

 acters develop in nature, where selection aims directly at life, will 

 they not be likely to develop also, unnoticed, under our own selec- 

 tion, especially when we do all within our power to preserve life P 1 



The presence or absence of a principle aside from selection, 

 yet responsible for the presence of characters, turns very largely 

 upon the question as to whether, after all, there are well-established 

 instances of characters independent of utility, and therefore of 

 selection. The presence of such characters is easily shown. For 

 example, what is the utility of the scrotum among mammals ? 

 Would it not have been better with sheep, for instance, if the 

 testicles had remained within the abdominal cavity, where they 

 develop, and where they would be safe, instead of descending 

 into an external sack exposed to frequent injury ? Undoubtedly 

 it would have been better for individuals, for many have not only 

 lost these organs, but their lives as well, from this unfortunate 

 position ; but the number lost is not sufficient to seriously affect 

 the race?' In other words, selection has aimed at this vulnerable 



1 It is noticeable that nature allows reproduction to go on unrestricted, and 

 then slays by the millions. Man cannot afford this wholesale destruction of num- 

 bers. He seeks to prevent undesirable births, a kind of advance selection that 

 has both its advantages and its disadvantages. 



2 This shows that what is bad for the individual is not necessarily bad for the 

 race ; conversely, what is best for the race is often hard upon or even fatal to the 

 individual. This is the very essence of selection. 



