American Museum of Natural Hismry 



DIVERGENCE OF RELATED FORMS 



Comparing the otter and the skunk, both classed in the "marten family", we cannot 

 see how the supposed ancestor became "modified" into either species. But we are 

 impressed by the fact that species which are so much alike in their fundamental 

 structures do fit such widely different surroundings 



parts of the United States, while the koalas and the kangaroos are limited to 

 the continent of Australia. Some species of plants and animals are quite cos- 

 mopolitan, ranging over large sections of the earth's surface. Most species, 

 however, are restricted to small areas. Certain giant tortoises and other 

 distinct forms are found only on the Galapagos Islands. 



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