NURTURE VERSUS NATURE 



Similarly the small winter rhubarb, with its 

 pencil-like stalks, as Mr. Burbank found it in Aus- 

 tralia, must be regarded as the dwarfed descend- 

 ant of some tropical plant of the elder day which 

 had been forced to modify its manner of growth 

 to meet altered conditions of climate, but which 

 retained in its germ-plasm, even as the Monterey 

 pine retained, the factors for relatively gigantic 

 growth, biding their time and ready to make re- 

 sponse to altered conditions of nurture. 



Their opportunity came when seeds of the plant 

 were brought from the antipodes to California, 

 just as the opportunity of the submerged factors 

 of the Monterey- pine was found when the migra- 

 tion was made in the opposite direction. 



AN EXAMPLE FEOM THE ANIMAL WOELD 



Were anyone disposed to doubt the validity of 

 this interpretation, to question whether environ- 

 ment has in reality such wonderful capacity to 

 alter the seeming mandates of heredity, evidence 

 in substantiation may be found in quite different 

 fields. 



Take, for example, the very familiar case of the 

 worker bee. This insect, as is well known, is an 

 immature and sterile female. Under normal con- 

 ditions in the hive, there are thousands of eggs, 

 each like all the others, and each destined to de- 

 velop into a sterile worker. 



But on occasion the mature workers in the hive 

 enlarge the cell in which one of these worker eggs 



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