CHAPTER V 

 THE PLIOCENE OF EUROPE, ASIA, AND NORTH AMERICA 



The Pliocene life of Europe and Asia is relatively well known, while 

 that of North America is imperfectly known; therefore only the broadest 

 time parallels can be dra^vn. The extension of our knowledge to the mam- 

 mals of India, China, and North Africa is full of interest and importance. 



4 U © . L- A 



Fig. 150. — Middle and Upper Pliocene. A period of continued continental elevation, 

 especially in Europe and Eastern North America. Seasons of aridity or summer drought, 

 increased aridity of the Great Plains of North America. South America connected with North 

 America by migration routes which allowed free interchange of mammals. Australia still 

 united with New Guinea and Tasmania. Rearranged after W. D. Matthew, 1908. 



In course of the Pliocene we enter upon the sixth grand faunal phase 

 (p. 304), which can only be understood through a preliminary survey of 

 the general changes and prevailing mammalian life in each of the northern 

 continents. 



The geographic conditions in Africa, Europe, Asia, and North AmcM-ica 

 favored the wide dispersal of similar forms of mammals, which reached a 



303 



