The gyrfalcon, an Arctic bird of prey, has survived a close brush with extinction; its numbers are now five times greater than when the use of DDT was sharply restricted in the early 1970's.
                    
                
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                Aextinction; its numbers are now five times greater than
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                Bextinction; its numbers are now five times more than
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                Cextinction, their numbers now fivefold what they were
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                Dextinction, now with fivefold the numbers they had
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                Eextinction, now with numbers five times greater than
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