XXIX. THE GEOGRAPHICAL DISTRIBUTION 

 OF ANIMALS 



Geographical distribution. — We visit menageries with 

 the keenest interest to see strange animals from strange 

 countries. It is evident from a moment's thought that 

 different countries are the homes of very different animals. 

 For example, the lion is found in Africa, the kangaroo in 

 Australia, the boa constrictor in South America, and so on 

 through a long list of examples that might be cited. In 

 North America we find the coyote, the black bear, and the 

 rattlesnake; but we do not find them in Europe. In the 

 United States, we find the grizzly bear in the Rocky Moun- 

 tains, but not in New England, or the southern states. 

 Again, the alligator is found in the swamps of the Gulf 

 states and nowhere else in the United States. Thus we 

 see that some animals, at least, live in certain well-defined 

 areas of the earth's surface, and it is easy to make a map, 

 showing the areas of the country in which many animals 

 are found. 



When the extent and location of the areas, or regions, 

 occupied by an animal have been ascertained, the geograph- 

 ical distribution of that animal may be said to have been 

 determined. 



Questions arising from the distribution of animals. — 

 Animals vary greatly in their ability to go from one place 

 to another. For example, a wild goose can go from Canada 

 to Florida much easier than a pond snail. There are also 



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