THE 



AMERICAN NATURALIST 



Vol. L. August, 1916 



THE FOEM OF EVOLUTIONAKY THEOEY THAT 

 MODEEN GENETICAL EESEAECH SEEMS 

 TO FAVOE 



DR. CHAS. B. DAVENPORT 

 Carnegie Station for Experimental Evolution, Cold Spring 



Nature produces those things which being continuously moved by a 

 eeita 1 1 pie contained in themselves arnve at a _ Aristotle> 



Contents 



I. General Statement of Theory of Evolution 



II. Support for the Theory from Collateral Fields 



1. Embryology 



2. Paleontology 



3. Experimental Breeding 



4. Eadiation Studies 



III. Certain Consequences of the Theory 



1. Adaptation 



2. Role of Selection 



V. Literature Cited 



I. General Statement of Theory of Evolution 

 The history of evolution, all will agree, has been from 

 the less specialized to the more specialized. The pre- 

 vailing view is that this greater specialization has been 

 achieved by adding qualities one by one to the less spe- 

 cialized until there has become built up through the ages 

 so complex structures as the higher types of organisms. 

 Organic evolution, from this view, has proceoded ah.mr 

 the same lines as the evolution of an old English manor 



449 



