CHAPTER XIV 

 FEET AND LEGS 



ARRIED far and wide by the power of flight, 

 no two species of birds have exactly similar 

 environments. When the wings cease their la- 

 bour and are folded close to the sides, the bird must depend 

 upon its feet to carry it to its food and to keep it out of 

 danger, w^hether its footing be in a tree-top or on a cliff; 

 in shallow water or on the deep; in mud, sand, or snow. 

 Thus we realize the need for many varied adaptations 

 in the way of feet and legs. 



Although birds are descended from five-toed ancestors, 

 yet no living wild bird, and none of those which we know 

 only as fossils, has more than four toes on each foot. The 

 disposition of these toes — four, three, or two, as the 

 case may be — is always in accordance with the habits of 

 the bird. 



The most common tj-pe of avian foot is that in w^hich 

 the arrangement is of three toes in front, with the fourth, 

 corresponding to our great toe, pointing backward. This 

 was the arrangement in our -first bird, the Archceopteryx, 

 and for perching birds, as well as for many others with 

 very different habits, it has stood the test of six millions 



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