SELECTIVE EVOLUTION 211 



become a lawyer, another to Pittsburgh to be- 

 come a steel maker, and another to the gold fields 

 of Nevada. 



Thus reaching out, always into new environ- 

 ments, some branch of this daisy family found 

 itself in the midst of a clump of trees^ — ^trees 

 which multiplied and gi-ew till they obscured the 

 sun and left the tiny plants in the obscurity of 

 dense shade. 



As the trees grew (and just as slowly, quite 

 likely), the daisies at their feet accommodated 

 themselves to their new environment — ^they 

 adapted themselves to the shade and moisture — 

 they had less competition, perhaps, from other 

 small plants and so became less sturdy — they 

 changed their color to the one best suited to at- 

 tract available messengers of reproduction. 



At this point we inteiTupted the evolution of 

 the African daisy by planting the white and 

 the orange together and securing, in the 

 pink one, an immediate blend of their divergent 

 heredities. 



But it requires no stretch of the imagination to 

 believe that, had we left them to their course, the 

 same end would have been accomplished a cen- 

 tury, or a thousand centuries, from now; that the 

 same migratory tendency which took the white 

 daisies into the woods would, in time, have 



