CREATION BY EVOLUTION 



swift running in order to catch the small animals on which 

 it lived and to escape from its enemies. It therefore began 

 to run on its hind legs like a kangaroo. There are only two 

 ways in which it could maintain such a bipedal gait — either 

 by carrying its body upright or by having a long tail to bal- 

 ance the head and body. The bird ancestor adopted the 

 latter plan. It had originally a spraddling walk, the feet 

 being turned out and kept far apart. This gait made neces- 

 sary a foot like that of a lizard, in which the big toe is the 

 shortest and the fourth toe much the longest, so that the 

 claws all lie on a straight line, at right angles to the direction 

 of the movement of the body. The increase in the length 

 of the toes is gained by an increase in the number of bones 

 or joints that support them ; the first has two joints, the next 

 three, and so on, the fourth having five. 



Any animal that must run fast must draw up its feet until 

 they lie under the body, and at the same time the foot must 

 be so shaped that the middle toe becomes the longest and 

 the second and fourth, which lie on each side of it, become 

 of equal length. This is the shape of the foot of a bird, 

 though birds still retain five joints in their fourth toe, 

 although they gain no advantage by so doing. These five 

 phalanges are inexplicable if the bird was created as it 

 stands, but they are easily understood if the bird was evolved 

 from a reptile. 



Any animal that uses its hind legs entirely for running or 

 for such simple movements as scratching, that has its feet 

 near the middle line of the body, and that runs fast, tends 

 to simplify the structure of its foot by fusing together bones 

 that were originally separate. In all ordinary animals the 

 ankle joint is made up of many small bones and is, even in 

 ourselves, a point of weakness. In a small chick these bones 

 are represented by cartilage, but as the bird grows up they 



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