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Interestingly , though thriving buffalo herds roamed and grazed the great prairies of North America for thousands of years , they have left few permanent markings on the landscape to recall their past presence .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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