The Mammals 



ber of bones as has the neck of a man. The elephant began 

 to develop long tusks and of such porportlons that It could 

 not crop the grass and tender shoots by reason of the Inter- 

 ference of Its tusks. Nature In order to overcome this diffi- 

 culty developed for It a flexible proboscis made up of 40,000 

 muscles, tendons and tissues with which It could gather and 

 feed Itself. The elephant would now be extinct from starva- 

 tion, had not Nature developed Its efficient trunk. 



In the history of all mammal life there Is, perhaps, no 

 more conclusive and satisfying Illustration of the change In 

 animal forms and of their adaptation to environment than 

 Is the evidence furnished by the horse. The horse's ancestry 

 may be traced back through an unbroken line for a period 

 of approximately 3,000,000 years at which time Its ancestors 

 were no larger than a fox with four complete toes on each 

 forefoot and three on each hind foot. There Is considerable 

 evidence to support the belief that the ancestors of the ances- 

 tors had five toes on each foot as do most of the present day 

 mammals. Through the fossil evidence which they have left 

 to us, their life's history may be traced through succeeding 

 stages of change and progress. During this long period of 

 time the horse's ancestors passed through many changes In 

 all parts of the body, but especially In the feet and teeth. 

 These small primitive animals forsook the forests and parted 

 company with their jungle cousins and selected the open 

 plains as a place for their habitation. The modern horse 

 In a wild state still selects the open plains and plateaus as a 

 place for Its habitation. Here on these sun baked plains and 

 plateaus the horse and its primitive ancestors have passed 

 through eleven successive stages or changes which have cul- 



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