170 MAMMALS OF THE PACIFIC WORLD 



there is little evidence of this connection so far as the mammals 

 are concerned. 



The Malayan Subregion is characterized by two gymnures 

 (rat-like insectivores), tree shrews, flying lemurs or caguans, 

 a number of fruit bats (the short-nosed and certain of the long- 

 tongued fruit bats), a false vampire, the slit-faced bat {Nyc- 

 teris), naked free-tail bat (Cheiromeles) , slow loris, crab-eating 

 and pig-tailed macaques, a variety of leaf monkeys and gibbons 

 (except the hoolock), small-clawed otter, linsang, binturong, 

 marbled cat, several small flying squirrels, striped and long- 

 nosed ground squirrels, pygmy squirrels, and the mouse-deer 

 or chevrotain. 



Virtually all of the mammals of the Malay Peninsula are 

 found in Sumatra; only a few are lacking from Borneo and 

 Java. Fossil evidence indicates that the fauna may have once 

 been more uniform ; remains of elephants and tapirs have been 

 found in Java where they are now absent. Extinction may ac- 

 count for some cases of discontinuous distribution, such as those 

 of the tiger and of the leopard. The tiger is absent from Borneo 

 and the leopard is known only from Java and the Kangean 

 Islands, but both are present on the Malay Peninsula. Sumatra, 

 Java, Bali, Borneo, and Palawan are all on the Asiatic conti- 

 nental shelf, and were part of the mainland in the not very dis- 

 tant past. 



The islands to the east and north (Celebes and Philippines) 

 have been separated for a very long time, since early in the Age 

 of Mammals at least. Islands, especially the smaller ones, offer 

 little variety of habitats, so that even if they were connected 

 with the mainland as a cape or peninsula, they would not have a 

 large mammal fauna. On the other hand, isolation of small 

 populations on islands may result sometimes in more rapid evo- 

 lutionary change than would be possible in large areas in the 

 case of a widespread population. Inbreeding of small popula- 

 tions may fix characters that otherwise would be swamped. 



The Malayan fauna is closely allied to those of the Indian 



