THE FIRST PROBLEM OF BIRD LIFE. 



FOOD AND ITS RELATION TO STRUCTURE. 



HERE we are, we plain birds, and we are hungry. What 

 shall we eat ? 



If we were boys, we should say, " Whatever we can get easi- 

 est, if we like it." Our choice would depend on whether we 

 preferred to gratify our appetites or our laziness ; also, though 

 all boys appear to have the same powers, on the presence or 

 absence of some peculiar accomplishment or intrepidity. The 

 skilful fisherman would catch fish, the daring climber might 

 climb trees for nuts, and perhaps those without such special 

 gifts would pick berries. Though all might prefer the same 

 food, some would be so much more active that they would 

 secure the whole of it before the others could get any. Rather 

 than go hungry the others would take second choice or third 

 choice or whatever was left, according to their strength and 

 skill. The art of getting your own dinner is to make up your 

 bill of fare of what you can get easily and in abundance 

 provided it suits your taste. 



Now if we plain birds must hunt our dinners, we ought, as 

 the boys say, "to have an eye out for the main chance." We 

 have our preferences, no doubt. We also have our fitness or 

 unfitness for getting what we prefer. Our " main chance " 

 lies, first of all, in our swiftness of locomotion, of one sort or 

 another. The one that flies better than he walks, covers most 

 ground by flying. He will, therefore, be most likely to secure 

 a dinner quickly by flying around in search of it. The one 

 that swims well, but flies poorly, travels farthest with least 



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