102 D. E. SAVAGE 



forms in the equatorial and southern hemisphere land areas, Mat- 

 thew decided that the Holarctic region has been the principal cen- 

 ter of evolution and dispersal of land vertebrates — that the southern 

 and tropical areas are refuges for primitive species. This thesis, 

 along with Matthew's erudition, had an overwhelming effect on 

 North America zoogeographers, as Myers (1938) pointed out. In 

 so far as non-mammalian vertebrates and land invertebrates are 

 concerned, Matthew's thesis has been strongly opposed by many 

 neontologic disciplines. Myers (1938, p. 351) believed that there 

 is no evidence for the North American origin of any of the South 

 American freshwater fishes. Schaeffer (1952, p. 231), however, as- 

 serted that centers of origin for the true freshwater fishes are un- 

 known but that some elements were present in South America by 

 the late Cretaceous. He concluded that Mesozoic freshwater fishes 

 suggest a dispersal relationship between South and North America 

 on the one hand, and between Africa and Eurasia on the other. 

 Darlington (1948, p. 110) concluded that the main center of evolu- 

 tion of dominant groups of freshwater fishes, amphibians, and 

 reptiles has been the tropical part of the Old World. Mayr (1946) 

 reemphasized that the classic zoogeographic terms such as Holarctic 

 and Nearctic cannot be applied usefully to the historical zoogeog- 

 graphy of birds. He believes that such terms add nothing, in the 

 geographic sense, to the meaning of standard geographic names for 

 the areas involved. And he proposes Pantropical, Panboreal, Old 

 World, North American, Pan-American and South American cen- 

 ters for avian origin and dispersal. Conclusions opposing Matthew's 

 generalizations are equally numerous in the literature of nonmarine 

 invertebrates, but Emerson (1952) believed that termite history 

 is in essential accord. Much of the opposing viewpoint stemmed 

 from Matthew's rationalization that the more progressive species 

 develop in an area of secularly changing climate — that the warm, 

 humid swamp and forest environments promote a "relatively slug- 

 ish life." Some of the contradictory statements have been weakened 

 by too great a dependence on the natural and organic phenomena 

 of the presently arranged and restricted climatic belts. Much of 

 Darlington's contention that the Old World Tropics were the main 

 center of evolution for cold-blooded vertebrates, for example, is 

 based on the knowledge "that the tropical part of the Old World 

 is the largest favorable area for existence of cold-blooded life. ..." 



