﻿Legs and Feet of Birds 



By C. WILLIAM BEEBE 



Curator of Birds, New York Zoological Park 



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,ARRIED far and wide by the 

 power of flight, no two species 

 of birds have exactly similar en- 

 vironments. Thus we realize the need 

 for many varied adaptations in the way 

 of feet and legs. When the wings cease 

 their labor and are folded close to the 

 side, the bird must depend upon its feet 

 to carry it to its food and to keep it 

 out of danger, — whether its footing be 

 in a tree-top or on a cliff; in shallow 

 water or on the deep; in mud, sand or 

 snow. 



Although birds are descended from 

 five-toed ancestors, yet no living 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 type of avian 

 foot is that in which the arrangement 

 is of three toes in front, with the fourth, corresponding to our great toe, 

 pointing backward. This was the arrangement in the fossil Archaeopteryx, 

 and for perching birds, as well as for many others with very different habits, 

 it has stood the test of the six millions of years, or thereabouts, since the 

 days of its venerable prototype. 



A classification of birds, generally accepted for many years, was based on 

 the uses of the feet, or mode of locomotion. In this scheme birds were 

 divided into the Runners, Scratchers, Climbers, Swimmers, Perchers, etc. 

 Although these exact divisions have long since been abandoned, yet it is 

 worthy of note that even in the most modern classifications many of 

 these groups hold good, although based on other and more fundamental 

 characteristics. Examples of these are the Ostrich -like birds, or Runners; 

 the Fowl-like birds, or Scratchers, and the Passeres, or Perching birds. 



From the tiny limbs of a Hummingbird to the gigantic shanks of an 

 Ostrich, the legs of birds, with very few exceptions, are covered with scales, 

 — most emphatic reminders of the reptilian ancestry of both these extreme 



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RED-CRESTED COCKATOO 



Showing two uses of the feet 



