472 



ANIMAL BIOLOGY 



attained. In looking for the effective cause of adaptation Aristotle 

 rejected the hypothesis of Empedocles (495-435 B.C.), which em- 

 bodied in crude form the idea of the survival of the fittest, and 

 substituted secondary natural laws to account for the apparent 

 design in nature. This was a sound induction by Aristotle from 

 his necessarily limited knowledge of nature, but had he accepted 

 the idea to account for adaptations, perhaps it would not be an 

 exaggeration to regard him as "the literal prophet of Darwinism." 



Fig. 308. — Erasmus Darwin. 



The thread of continuity in evolutionary thought is not broken 

 from Aristotle to the present, but from the strictly biological 

 viewpoint two Frenchmen, Buffon and Lamarck, and two English- 

 men, Erasmus Darwin and his grandson, Charles Darwin, stand 

 preeminent. 



Buffon (1707-1788) was a peculiarly happy combination of 

 entertainer and scientist who found expression in each new volume 

 of his great Natural History. And it was largely, so to speak, be- 

 tween the lines of this work that Buffon's evolutionary ideas were 

 displayed ; apparently beyond the reach of the censor and dilettante. 

 It is not strange, therefore, that it is often difficult to decide just 

 how much weight is to be placed on some of his statements ; though 

 certainly it is not exaggerating to ascribe to him not only the recog- 

 nition of the factors of geographical isolation, struggle for existence, 



