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BIOLOGY FOR BEGINNERS 



Gulf of Mexico directly over 500 to 700 miles of open water. 

 Others follow the coasts or river valleys and may even go by one 



From American Museum of Natural History. 



FIG. 102. The birds carry their plumes only during the nesting season; 

 killing the parents means the slow starvation of the young. 



route and return by another. How do they know the way? Keen 

 sight may help, but not over water or through dark nights and fogs. 

 They do not seem to follow water ways or mountain ranges in 



