ESSAYS ON EVOLUTION. 



483 



" changed conditions of life." This is the conclusion of all ecologists 

 to-day. 



We now come to " Theories of Evolution." With regard to the 

 Lamarckian and the Spencerian adaptation of it, Professor Poulton 

 says : " If it is true that such [acquired] characters are transmitted, 

 then the foundation of the theory is secure." * 



The professor mentions a common question : " Why do we not find 

 in the palaeontological series the records of individual failures ? " just 

 as one asks, " Why do they not occur now wherever seedlings grow up 

 under ' changed conditions of life ' " as when the seeds have come from 

 distant localities ? The author replies : " What is a failure ? Failure 

 means, according to natural selection, the failure to produce offspring." 

 This, however, is not Darwin's description, but an obvious result. The 

 " failure " first occurs in the young organism developing some " injurious " 

 variation,"* - which kills it before it arrives at maturity. 



Professor Poulton, like Dr. Wallace, says : " We cannot expect to find 

 evidence of the survival of the fittest among the individuals of a 

 species." 



One at once asks, Why not ? According to Darwin, we ought to see 

 them everywhere, that is as soon as seeds are sown, whether naturally 

 by dispersion, or artificially by man, in some strongly marked differences 

 of the surrounding conditions. Darwinians have made this statement 

 repeatedly, but no reason has ever been forthcoming to support it. 



On the other hand, whenever we look for the " results of the direct 

 action of changed conditions of life," Darwin's own way of accounting 

 for new species,! they, i.e. the resulting variations, are always and in 

 every individual "definite," i.e. in adaptation to the new environment. 

 The above admission appears to be due to the fact that "indefinite" 

 variations never do exist. No ecologist of to-day can recognize any 

 value in such an admission. 



The author mentions another objection : " Natural selection, it is said, 

 can never account for the beginnings of things. Until the organ is raised 

 to a useful level, selection can have nothing to do with it." Professor 

 Poulton replies : " At first sight this is a serious objection, but it suggests 

 its own answer, viz. that an organ so rarely develops ah initio." But, 

 would be the retort, 11 every organ must have done so once." 



Here, again, Darwin's explanation appears to be forgotten. The com- 

 mencement of an organ is a new "favourable " or adaptive variation, the 

 individual variation enables it to survive. It is only the individuals with 

 "injurious " variations which perish — or would, if any such existed. 



Chapter IV. deals with " Theories of Heredity," and Professor 

 Poulton discusses the two well known, viz. Darwin's theory of pangenesis, 

 to account for the transmission of acquired somatic characters, and Weis- 

 maun's, which limits it to such influence as can reach the germ-plasm. 

 The author shows that pangenesis has too many difficulties to make it 

 acceptable ; but " if the effects of use and disuse are transmitted, the 



* The reader will find ample proofs of this in The Heredity of Acquired 

 Characters in Plants, by G. Henslow. 

 t Origin, dx. 6th Ed. p. 63. 

 X An. and PI. under Dom. ii. 271. 



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