THE INFLUENCE OF DARWIN ON THE NATURAL 



SCIENCES. 



By GEORGE LINCOLN GOODALE. 



We are to examine the more striking features of a revolution 

 which began half a century ago. The smoke and dust of contro- 

 versy have drifted away, and it is now possible to see with some 

 degree of clearness the magnitude of the issue and the nature of 

 the reconstruction. In order to appreciate the completeness of the 

 change, we must contrast, as fully as our time permits, the condi- 

 tion of the natural sciences fifty years ago with their state at the 

 present time. 



In 1858 Alfred Russell Wallace and Charles Darwin first gave 

 to the public their fruitful suggestion in regard to the struggle for 

 existence and the survival of the fittest. In the following year 

 Darwin embodied this idea in his " Origin of Species," and illus- 

 trated it fully. Those two dates mark the beginning of a new era 

 in natural science. By natural science, as distinguished from 

 physical science on the one hand, and from mental and moral science 

 on the other, is commonly meant that department of investigation 

 which deals with living and extinct plants and animals, especially 

 with regard to their structure and distribution. The century end- 

 ing in 1859 was remarkable for its persistent attachment to a dogma 

 in natural science which had proved more and more embarrassing 

 as the century advanced. This dogma is known as that of the 

 fixity, or permanence, of species. 



The word species, denoting a particular kind of mineral, plant or 

 animal, is very old in its general application, but it assumed in 1750 

 a definite meaning at the hands of a great reformer of natural his- 

 tory, Linnaeus, of Sweden. He found the term used vaguely, and 

 he gave to it a restricted signification. Everybody recognizes the 

 fact that the living world around us is composed of individuals 

 which resemble each other more or less closely. When these in- 



