THE SUMMIT OF THE YEARS 



animals that are defenseless, like the rabbit, have 

 speed and are prolific; that animals that are self- 

 armed, like the tortoise and the porcupine and the 

 skunk, are slow and dull of wit. One does not need 

 elaborate experiments to prove that the pigeon would 

 be slower in learning to run the maze than a squirrel 

 or a rat; he knows that all animals are more or less 

 imitative, that the young imitate the old, and the 

 old imitate one another; that monkeys by their be- 

 havior alone are nearer man than the dog or the cat. 



The work of the experimentalist may supplement 

 that of the field observer, but it cannot take its 

 place. " Experiment has an advantage over observa- 

 tion," says a German writer on logic, "only so far 

 as it is capable of supplementing the usual deficien- 

 cies of the latter." 



We cannot make Darwins in the laboratory, 

 though the laboratory may give Darwin a fact or a 

 hint now and then that will be of service to him. 



If our experimenters can now prove that birds 

 are color-blind they will raise havoc with Darwin's 

 sexual selection theory. Let them experiment upon 

 the peacock, the Argus pheasant, and other birds of 

 brilliant plumage. The males of many of our small 

 birds are brilliantly colored; what part does this play 

 in their lives? If orange, crimson, yellow, blue, and 

 the various metallic lustres and changing irises are 

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