CHAPTER XVII 



Organic Selection 



A compromise between Darwinism and Lamarckism. — Acquired 

 variations coincide with germinal variations. — Parallel adap- 

 tation, complex instincts. — The theories of Baldwin and 

 Osborn. — Advantages and defects of the theory. 



BESIDES Neo-Darwinism, or pure selectionism, 

 and Lamarckism, there are certain theories, not 

 as comprehensive as those two fundamental and typ- 

 ical systems, which do not play as important a part 

 in the discussion of the main biological problems and 

 which cannot be defined as either Darwinian or La- 

 marckian. Some of them diverge more or less from 

 both systems ; some endeavour to combine them. 



Among the latter we can mention the theory of or- 

 ganic selection which was formulated almost simul- 

 taneously, although with slight differences of detail, 

 by Baldwin and Osborn in America, and by Lloyd 

 Morgan in England. It postulates both natural se- 

 lection (which it regards as the main factor of evolu- 

 tion), and the heredity of acquired characters, and it 

 endeavours to dispose of the grave objections raised 

 against the theory of natural selection by supple- 

 menting it with direct individual adaptation. 



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