ANIMAL HABITATS 19 



extends high above the forest floor. While the 

 forest canopy is bathed in fierce tropical sunlight, 

 the floor below is in deep shadow broken only by 

 the intense flecks of sunlight that filter through 

 the scant openings in the leafy roof. Above, 

 tropical gales may blow; the temperature changes 

 rapidly from noon heat to midnight chill, for the 

 night is the winter of the tropics; the humidity 

 of the air also varies widely. At the forest floor, 

 throughout the rainy tropics of the world, the 

 wind is absent and only slight breaths of air 

 relieve the forest stagnation; the temperature 

 in constantly shaded regions may change less 

 than two degrees in a whole week and the humidity 

 is similarly constant. Only in caves, deep in the 

 soil or in the shadowy depths of the water do the 

 environmental conditions become more constant. 

 But the animals living under these conditions 

 in the forests of South America belong to different 

 species, families, and even to different orders 

 from those of the physically similar forests of 

 Africa and Asia. For example, in America the 

 mammals of the tropical forest floor are mainly 

 guinea pig-like rodents with claws, which are 

 replaced in Africa by the hooved antelopes. The 

 hairy anteaters of the South American forest 

 have their counterpart in the scaly anteaters of 

 Africa, which while similar in feeding habits, belong 



