MAMMALS 



211 



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Miohippus 



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Mcsottippus' 



FIG. 382. SKELETONS OF FEET OF MAMMALS. 



P, horse; D, dolphin; E, elephant; A, monkey; T, tiger; O, aurochs; 



F, sloth ; M, mole. 



Question: Explain how each is adapted to its specialized function. 



According to the usual rule, they tended to u B 

 increase faster than the food supply, and there 

 were continual contests for food. Those whose 

 claws and teeth were sharper drove the others 

 from the food, or preyed upon them. Thus the 

 specialization into the bold flesh eating beasts 

 of prey and the timid vegetable feeders began. 

 Which of the flesh eaters has already been stud- 

 ied at length ? The insectivora escaped their 

 enemies and found food by learning to burrow 

 or fly. The rodents accomplished the same result either by 

 acquiring great agility in climbing, or by living in holes, or 

 by running. The proboscidians acquired enormous size 

 and strength. The hoofed animals found safety in flight. 



FIG. 383. 



Feet of the 



ancestors of 



the horse. 



