ADAPTATION 



235 



parental care, however; the birds are oviparous, but their care of 

 their young is a matter of common knowledge. In all cases, of 

 course, the rate of reproduction must be great enough to offset 

 destruction or the species must ultimately become extinct. 



Fig. 142. — Beaks and feet of birds. A, foot of bald eagle; B, head of turkey 

 vulture, a carrion eater; C, beaks of seed-eating birds; D, beak and foot of 

 swallow, an insect eater. (From Chapman's Handbook of Birds of Eastern 

 North America, with the permission of D. Appleton and Company.) 



During the independent life of the individual it escapes various 

 dangers by running away, by resisting them through combat, or by 

 various conceahng or repellent means. Some animals are ar- 

 mored, and are therefore almost immune from attack by others, 

 and still others are protected by such peculiar powers as autot- 

 omy. 



Armor. Armor was highly developed in some of the extinct 

 reptiles, such as Stegosaurus and Triceratops (Fig. 143). These 



