GIANT ROAD-MAKERS 121 



and they are wise enough not to neglect either, and 

 thus to rob themselves of important advantages. 



For the purpose of the preservation of a species, 

 the ground is necessary for nest-building and in 

 many cases for feeding, and the air is equally 

 needed as an avenue of flight in time of danger. 

 Birds will never be able to cope successfully with 

 the many enemies more powerful than they that 

 inhabit the surface of the earth, and air flight is 

 their only sure means of safety. And when they 

 lose that power they must inevitably, sooner or 

 later, be overwhelmed and wiped out, no matter 

 how prolific they may be in breeding, or how in- 

 telligent in matters of foraging. 



Only in such places surrounded by water since 

 time immemorial and far removed from continents, 

 where no animals of a flesh-eating nature can reach 

 them, is it possible for birds to lose their power of 

 flight and yet survive. Giants though some may 

 be, many, if not all, must succumb in time. Excep- 

 tions to this rule may immediately occur to the mind 

 of the reader, but considered as a class, this deduc- 

 tion is certainly true of them. 



Road-making, like many other activities in the 

 lives of birds and men, is good to a point; but when 

 carried beyond certain limits, when its influence 

 tends to violate the immutable laws of nature, then 



