A DEFINITION OF E\'0LUT10N 



I cannot remember a single first-formed hypothesis which had not after 

 a time to be given up or greatly modified." 



He concluded his autobiography with the statement that ". . . my suc- 

 cess as a man of science, whatever this may have amoimted to, has been 

 determined ... by complex and diversified mental qualities . . . the love of 

 science— unbounded patience in long reflecting over any subject— industry 

 in observing and collecting facts— and a fair share of invention as well as 

 of common sense. With such moderate abilities as I possess, it is trulv 

 surprising that I should have influenced to a considerable extent the belief 

 of scientific men on some important points. 



Darwin died on April 19, 1882, at the age of seventy-one, and was 

 buried in Westminster Abbey near the grave of Newton. 



ALFRED RUSSEL WALLACE— CO-DISCOYERER 



Alfred Russel Wallace was born on January 8, 1823. As a yoimg man, he 

 made a journey of explorations into the Amazon Valley with H. W. Bates, 

 a distinguished entomologist. This served as the basis for a book, "Travels 

 on the Amazon and Rio Negro," which he published in 1853. In 1854, he 

 began a zoological exploration of the Malay Archipelago, a work which 

 occupied him until 1862, and which resulted in a book entitled "The 

 Malay Archipelago," which he published in 1869. While on the island of 

 Ternate in February, 1858, he was stricken with intermittent fever. During 

 an attack of the fever, he happened to think of Malthus' "Essay on Popu- 

 lation," and "suddenly there flashed upon me the idea of the survival of 

 the fittest." The theory was thought out during the rest of the ague fit, 

 written out roughly the same evening, and then written out in full in the 

 two succeeding evenings. The resulting paper he sent to Darwin, with 

 whom he was somewhat acquainted. The rest of this story has been told 

 above. 



Wallace also was active in the further development of evolutionary 

 literature. His major contribution was in the field of biogeographv. His 

 most important work in this field was "Geographical Distribution of Ani- 

 mals," which was published in 1876. He expressed the hope that this book 

 might do for the biogeographical chapters of the "Origin" what Darwin's 

 book on "The Variation of Plants and Animals under Domestication" had 

 done for the corresponding chapters of the "Origin." This hope was real- 

 ized, for this was ]K>rha])s the most outstanding of the classical treatments 

 of bioge()gra])hv. A second book relating to geograjihieal ])robl('ins of 

 evolution, "Island Life," appeared in 1880. lie also publisluxl "(lontiibu- 

 tions to tlu' Tlu'orx of Natural Selection " iu 1870, "Tropical Nature and 

 Other Essavs" in 1878, and "Darwinism" in 1889. While Wallace shares 

 with Darwin the honor of first publication upon the theorv of the origiii 

 of sjiecies b\ natinal selection, lu^ alwa\\s ver\" gen(>rouslv (and j'jroptMh-, 

 lor it was the "Origin w hieh con\ inced seicMitists ) gax'c J)ar\\ in full credit 

 for the theory, as indicated bv the title of the last book mentioned above. 

 Wallace died on November 7, 1913. 



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