790 ANIMALS AND THEIR ENVIRONMENT 



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Figure 38.7. The tundra bionie. Above, View of the low tundra near Churchill, 

 Manitoba, in July. Note the numerous ponds. Below, View of tundra vegetation show- 

 ing "hmipy" nature of low tundra and a characteristic tundra bird, the willow ptar- 

 migan. (Lower photo by C. Lynn Haywood.) 



San Joaquin Valley of California into the Sierras, one passes from desert 

 and chapparal through deciduous forest and coniferous forest to, above 

 timberline, a region resembling the tundra of the Arctic. 



Tundra. The tundra biome (Fig. 38.7), foimd in northern North 

 America, northern Europe and Siberia, is characterized by low tempera- 

 tures and a very short growing season. The plants are lichens, mosses, 

 grasses and a few low shrubs. The chief animals are the caribou of 

 North America and the reindeer of Europe and Siberia, the musk ox, 

 arctic hare, arctic fox, lemming, snowy owl and ptarmigan. These are 

 joined during the short summer by many migiatory birds and by large 

 numbers of insects, especially mosquitoes and black flies. 



