NATURAL REGIONS OF THE GLOBE 11 



rence of many bulbous plants, speaks to a climate where 

 dry and wet seasons alternate, and so on. The depen- 

 dence of the more active animal upon its surroundings is 

 less intimate than that of the passive plant, but even 

 here the characters of the animals of a region tell us 

 something of the physical features of that region. That 

 we find in Brazil, for example, animals so thoroughly 

 adapted to the arboreal life as sloths, marmosets, 

 monkeys, and so forth, suggests at once that dense 

 forest occurs in the region. That Africa has an 

 enormous number of antelopes — enormous both as 

 regards species and individuals — suggests the existence 

 in that continent of open plains, and so with other 

 regions. 



The botanists recognize three great plant formations, 

 which roughly divide the surface of the land among 

 them. These are woodland, grassland, and desert. 

 Such a simple division would help us little in the case 

 of animals, but as all animals depend ultimately for 

 their food upon plants, a modification of this classi- 

 fication may serve as a framework in the study of 

 animal distribution. There is, for example, a consider- 

 able difference in the life conditions of animals which 

 live in regions where the winter cold periodically checks 

 plant growth, as compared with those where no such 

 temperature check occurs. This gives us a first dis- 

 tinction between the animals of cold or temperate 

 regions and those of tropical regions. In both of these 

 forest, grassland, and desert occur, but it is possible to 

 pick out certain weU-defined types in order to study 

 their faunas separately. Thus, among the various forms 

 of temperate forest, the Taiga or coniferous forest of 

 Asia and North America has a weU-defined assemblage 

 of animals showing some interesting adaptations. 



