ANIMAL HABITATS 29 



desert. Such deserts may be considered together 

 with the desert-like polar regions as forming a 

 yet more extensive habitat. There the rainfall 

 is also low and continued cold is an additional 

 life handicap. This indicates either that animal 

 habitats and the animal communities that inhabit 

 them can be analyzed into simple terms or on the 

 other hand, that the simple units can be united 

 into fairly complex regions or communities which 

 still have common elements. 



