436 LAND ANIMALS 



of species of trees — the fewer are the forest-limited animals present. 

 Arboreal habits give way to semi-arboreal ones, and the number of 

 invaders more characteristic of the open grasslands becomes greater. 

 These changes become evident even in the tropics, particularly in 

 regions of monsoons where well-defined dry and rainy seasons alter- 

 nate, and in mountains with their more extreme conditions. The dif- 

 ferences become still more distinct in temperate and cold regions. The 

 height of the forest trees diminishes until, at the timber line, whether 

 at the tundra or on mountains, they stand no higher than a man. 



Bears are absent in the dense tropical forests of Africa and South 

 America, and though some species occur in the Malayan forests they 

 are more common in the less densely forested temperate regions. Deer, 

 which are not characteristically forest animals in the tropics, invade 

 the temperate forests. In Asia a few monkeys and the tiger are found 

 in forests north of the Himalayas. The species or genera of animals 

 in the northern forests become more similar on the two sides of the 

 Atlantic, or better, on the two sides of Bering Strait; these faunae are 

 taxonomically more clearly related than +hose of the different world 

 divisions of the tropical forests. 



Animal communities of temperate deciduous forests. — The only 

 typical temperate forest mammals are the squirrels, the flying squir- 

 rels, dormice, martens, the wildcat, and the lynx. The more striking 

 animals of these forests are ground dwelling and cursorial; red deer, 

 roe deer, and moose are examples. Badgers and foxes are at home 

 along the forest margin. Wolves range out into the neighboring grass- 

 lands, obtaining concealment in the forest. 



Woodpeckers, doves, crossbills, finches, jays, woodcock, wood 

 thrushes, hawks, and owls find their food even in the deep forest, while 

 as in the tropics many others are to be found in the forest margins, 

 including ravens, the black stork and herons in Eurasia, and crows, 

 herons, and brown thrashers in America. 



The reduced number of species of trees is far less critical for the 

 higher vertebrates than for other animals, especially for those forms 

 that approach stenophagy. There are mammals and birds that are 

 confined to the temperate deciduous forests and are absent in the conif- 

 erous ones. 



Temperate deciduous forests are forests of broad thin leaves that 

 have a cold winter season. These differ from tropical forests in that 

 they are located in higher latitudes with a mean annual temperature 

 of 10°-20°. The rainfall is from 75 to 150 cm., approximately equally 

 distributed throughout the year. The ratio of rainfall to evaporation 

 varies from about 80 to 130%. Such forests are less luxuriant than 



