A "USE'* FOR EVERYTHING? 105 



some of these books have been written by persons 

 who have done noble work for truth. 



This is one of the greatest faults with the popular 

 outlook on nature — the belief that every feature 

 of plant or animal has a distinct use in the present 

 time and that one has only to look to see what that 

 use is. Persons often look at the little things and 

 miss the big ones. They look for the hairs and 

 miss the plant. They see the unusual and rare and 

 overlook the common. I wish that people might 

 learn to see dandelions. 



Having seen a thing of which the function is not 

 evident, they assume a condition and jump at a 

 conclusion. A plant has poison ; various creatures 

 eat plants ; the creatures are killed by poison : 

 therefore the plant has poison to protect itself from 

 the creatures. Now, it may even be true that the 

 poison does protect the plant, but there is no proof 

 thereby that the poison was produced for that 

 purpose. The physiologist may find that the poison 

 in the given case is merely a waste product of some 

 chemical metabolism, and that the plant is fortunate 

 in getting rid of it. If the plant is now and then 

 protected, the result is only an incident. If 

 it should appear that one kind of plant, by natural 

 selection, has developed poison in order to protect 

 itself, the fact would be spread abroad in book and 

 magazine, but it would not be stated that it was one 

 case out of a thousand. The exception is enlarged 

 into the rule. Persons like to write about perfect 

 adaptation of means to ends, without a slip or break 

 in the process. A teacher brought a flower and 



