100 WHAT EVOLUTION IS 



4. DARWINISM 



Darwinism, or as it is often called 

 natural selection, is an explanation of 

 evolution that originated independ- 

 ently in the minds of Darwin and 

 of Wallace. It is best stated in Dar- 

 win's memorable work ''The Origin 

 of Species" (1859), without doubt 

 the most significant single publication 

 of the nineteenth century. As a re- 

 sult of the discussion called forth by 

 the appearance of this work, two 

 great steps in the progress of biology 

 were accomplished; first, the accept- 

 ance of descent with modification, 

 instead of special creation as the 

 order of organic nature, and, sec- 

 ondly, the establishment of natural 

 selection as a driving force in evolu- 

 tion. The first of these has already 



