Xo. 510] PROBLEMS IN PLANT ECOLOGY 361 



learned the habits of the oak, and found just how to tap 

 it ? How much more sane it is to regard these and all 

 other plant reactions as brought about through the in- 

 fluence of specific stimuli, treating any advantage that 

 may come (or any disadvantage) as quite incidental to 

 the main problem ! 



At the present day Lamarckism and adaptation are 

 scarcely as detrimental to ecological thinking as is the 

 misapplication of Natural Selection. The publication 

 of the " Origin of Species" in 1859 influenced biological 

 thought more profoundly than any other work of all his- 

 tory. It compelled the world to accept the doctrine of 

 organic evolution, and it showed most clearly why certain 

 species die and others live. But it shed only a little light 

 on the great questions involved in the evolution of new 

 species. In view of this it seems most unfortunate that 

 the book was entitled "The Origin of Species"; the 

 alternative title commonly printed just beneath in smaller 

 type presents the real thesis of the book : ' ' The Preserva- 

 tion of Favored Races in the Struggle for Life." Per- 

 haps in part because of the title, but more because of 

 Darwin's over-zealous supporters, natural selection has 

 been made a fetish and has been supposed to account for 

 new forms and structures, as well as for their preserva- 

 tion. In other words, it has been erroneously regarded 

 by many as a theory of evolution instead of a means of 

 accounting for the perpetuation or destruction of species 

 previously formed. The theory of natural selection has 

 worked great harm in the ecological study of plant struc- 

 tures. Thorny plants have been supposed to be selected 

 by reason of animal incursion, and such complex things 

 as floral structures have been supposed to be the result 

 of parallel selection on the part of flowers and insects. 

 There is no adequate evidence, experimental or otherwise, 

 for views of this character. Such experimental work as 

 has been done appears to show that the success or failure 

 of a plant rarely depends upon this or that little advan- 

 tage, upon which natural selection may be supposed to 



