PERPETUATION OF USELESS CHARACTERS 5 



While the various kinds of functionless members and anatomical 

 features that have been discussed so far complicate the task of the 

 physiological anatomist, they do not fall altogether outside the scope of 

 his subject, nor do they involve conceptions which conflict with its 

 fundamental principles. It is otherwise, however, with such members 

 and features as appear to have been devoid of physiological value <</> 

 initio. If purely individual variations be ignored for the present, and 

 if attention be further restricted to undoubtedly hereditary characters, 

 the question which first demands consideration relates to the occurrence 

 or rather to the possibility of the existence of arrangements in the 

 structure of an organism that are devoid of utility from their very 

 first appearance. The answer to this question will depend largely upon 

 the point of view from which one approaches the subject of evolution. 

 It must be in the negative, if Charles Darwin's theory of natural 

 selection be accepted ; for if, as Darwin assumed, individual variations 

 may take place in any direction tvhatsoever, then it is only owing to the 

 natural selection which occurs in the struggle for existence that living 

 beings are able to acquire a more complex organisation and thus 

 gradually to rise to a higher plane of evolution. On this assumption 

 a newly acquired morphological peculiarity can never be perpetuated 

 by inheritance, unless it performs a definite service in the interests 

 of the organism and hence proves useful in the struggle for exist- 

 ence. Utterly useless features, on the other hand, cannot possibly 

 survive in these circumstances. From the point of view of natural 

 selection all morphological characters are in the nature of useful 

 adaptations, or at any rate must have fulfilled this condition at the 

 time when they became " fixed." 



If on the contrary one assumes with Nageli that the progressive 

 evolution of organisms is controlled by inherent tendencies that is to 

 say, by conditions located in the living substance itself or, in other 

 words, that the struggle for existence, instead of effecting the selection 

 of useful characters, merely ensures the elimination of harmful or useless 

 peculiarities, then the question propounded above must be answered in 

 the affirmative, with certain reservations. For in the absence of the 

 struggle for existence and . of the unrestricted competition thereby 

 implied, not only useful features produced according to Nageli by direct 

 adaptation but also all useless morphological peculiarities would be 

 inherited, since both types of character develop under the compulsion 

 of internal forces, as it were automatically. If we concede this point, 

 we cannot deny the possibility of the inheritance of such structural 

 features as are useless without being actually harmful and hence 

 negligible in the struggle for existence, particularly where competition 

 takes a relatively mild form owing to the specially favourable character 



