352 ANIMALS OF THE PAST 



era, we find a great similarity to the life as it now exists. 

 The great advance in this era was the remarkable develop- 

 ment of mammals. The great reptiles disappeared and 

 mammals took their places. In the ocean we find huge 

 whalelike creatures seventy feet long. Remains of the 

 Zeuglodon have been found in great abundance in Alabama. 

 The early ancestors of the cat, panther, wolf, etc., appear in 

 this era. The elephant family was represented by the 

 huge mammoth (Fig. 233) and mastodon, neither of which, 

 however, was much if any larger than some of the largest 

 living elephants. Insects and birds were abundant in this 

 era. Monkeys, horses, and rhinoceroses appeared in the 

 cenozoic. Later came the buffaloes, hyenas, elks, etc. 



The coming of man marked the climax in the progress 

 of life upon the globe. Just how, or just when he came, 

 we do not know, but we have sure proof that he has 

 existed upon the earth many thousands of years. 



Significant features of the history of animal life on the 

 earth. — It has been the attempt of the author to show that 

 the present animals on the earth are all connected with one 

 another, from the lowest to the highest, by intermediate 

 forms, and that all hfe has gradually arisen from a very 

 simple, probably one-celled animal. In examining the 

 history of the appearance of animals on the earth, we find 

 the same thing to be clearly evident. The first form of life 

 we found was very simple indeed, and lived wholly in the 

 water. This was succeeded in a later age by higher life 

 that finally came to live on land. This, in turn, was suc- 

 ceeded by higher and higher and more varied forms, until 

 it culminated in the appearance of man, the crowning feature 

 of hfe. 



