242 THE FOUNDATIONS OF ZOOLOGY 



of living things, which it takes as it finds them, it demonstrates 

 that the features in which the species of living things differ from 

 one another, are due to influences that are still at work, and open 

 to observation and experiment by scientific methods. 



Darwin shows that individual animals and plants, even those 

 of the same species, differ greatly among themselves; that these 

 differences may be exhibited by any characteristic whatever — 

 those upon which the species and genera of the systematist are 

 based, as well as those which had been held to be varietal or 

 individual; that, notwithstanding these differences, offspring tend 

 to resemble their parents, and to be like them in the main ; that 

 man is able to bring about, and to fix or establish, changes of 

 type, by breeding from selected parents; and that features exactly 

 like those upon which species are based may be modified or pro- 

 duced by selection ; and that what is thus accomplished by man 

 may come about with equal certainty, even if more slowly, in 

 nature through the struggle for existence and the extermination 

 of the unsuccessful. 



None of these propositions are very profound, or very difficult 

 to grasp. They call for no unexampled powers of abstract thought, 

 for they lie so near the surface that they have been formulated 

 again and again. 



Darwin says : " My brother, who is a very sagacious man, 

 always said, * You will find that some one has been before you ' ; " 

 and on the first page of the first edition of the "Origin," which 

 was published in November, 1859, he says, after telling the reader 

 that the subject has occupied him steadily for twenty years : " My 

 work is now (1859) nearly finished; but as it will take me many 

 more years to complete it, and as my health is far from strong, 

 I have been urged to publish this Abstract. I have the more 

 especially been induced to do this, as Mr. Wallace, who is now 

 studying the natural history of the Malay archipelago, has arrived 

 at almost exactly the same general conclusions that I have on 

 the origin of species. In 1858 he sent me a memoir on this 

 subject, with a request that I would forward it to Sir Charles 

 Lyell, who sent it to the Linnean Society, and it is published 

 in the third volume of the Journal of that Society. Sir Charles 

 Lyell and Dr. Hooker, who both knew of my work, — the lattei 



