THE EVOLUTION OF MAN 



(A Paper read before the Mendelian Society) 



By J. T. CUNNINGHAM, M.A., F.Z.S. 



The present paper is an attempt to consider some of the modern 

 conceptions of biology in relation to the human species. With 

 regard to species in general the Darwinian theory assumed that 

 the differences between species were differences of adaptation, 

 that specific characters were useful, that species were adapted to 

 different modes of life. It has, on the other hand, been main- 

 tained by later zoologists that in the vast majority of specific 

 characters there is no evidence of such utility, or of correlation 

 with useful characters, and the pure Darwinian doctrine is now 

 held by a few pious disciples of Darwin as an article of faith 

 rather than as a scientific conclusion. The most eminent 

 systematists distinguish now, as those of pre-Darwinian days 

 did, between diagnostic characters, which are of chief systematic 

 value, and adaptive characters, which for purposes of classification 

 are often rather misleading than significant. The more useless 

 a character is the more valuable it is as an indication of affinity. 

 One modern school of evolutionists, recognising the uselessness 

 of diagnostic characters, holds that they have not been evolved 

 by selection but have arisen spontaneously as mutations ; and, 

 with the usual tendency to carry a doctrine to extremes, they 

 maintain that all characters are independent of utility, that all 

 arose as mutations. The American investigator, Dr. T. H. 

 Morgan, has published a book specially devoted to this doctrine, 

 in which he endeavours to show that adaptations do not really 

 exist, that mutations have occurred which could only survive 

 under special conditions of life, which in some cases the modified 

 creatures have found, so that habits have been determined by 

 structure, not structure by habits. Thus, in the short period 

 of half a century, we have had the swing of the pendulum of 

 biological opinion from one extreme to another, from the belief 

 that all characters were adaptive or useful to the belief that none 

 were adaptive. In the meantime the common-sense view has 



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