ACCEPTING THE UNIVERSE 



nate the other birds; they are a natural check on 

 their undue increase. Nature's checks and balances 

 are all important. When species subsist upon spe- 

 cies, as weasels upon rodents and hawks upon other 

 birds, there seems to be some law that keeps the 

 bloodthirsty in check. Why should there be so few 

 weasels, since they appear as prolific as their vic- 

 tims? Why so few pigeon hawks, since the hawks 

 have no natural enemies, while the trees swarm with 

 finches and robins? 



The conflicting interests in Nature sooner or 

 later adjust themselves; her checks and balances 

 bring about her equilibrium. In vegetation rivalries 

 and antagonisms bring about adaptations. The 

 mosses and the ferns and the tender wood plants 

 grow beneath the oaks and the pines and are 

 favored by the shade and protection which the 

 latter afford them. The farmer's seeding of grass 

 and clover takes better under the shade of the oats 

 than it would upon the naked ground. In Africa 

 some species of flesh-eaters live upon the leavings 

 of larger and stronger species, and in the tropics 

 certain birds become benefactors of the cattle by 

 preying upon the insects that pester them. Fabre 

 tells of certain insect hosts that blindly favor the 

 parasites that destroy them. The scheme has 

 worked itself out that way and Nature is satisfied. 

 Victim or victor, host or parasite, it is all one to her. 

 Life goes on, and all forms of it are hers. 



146 



