This undated photo provided by the Cleveland Metroparks Zoo shows Blackie a Nile hippopotamus. Blackie, who came to the zoo from Africa in 1955, was euthanized Monday, Jan. 13, 2014, due to "advanced ... more 
This undated photo provided by the Cleveland Metroparks Zoo shows Blackie a Nile hippopotamus. Blackie, who came to the zoo from Africa in 1955, was euthanized Monday, Jan. 13, 2014, due to "advanced age-related ailments." The zoo says he was about 59 years-old and believed to be the oldest in North America. (AP Photo/Cleveland Metroparks Zoo) less 
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Associated Press | Photo By Cleveland Metroparks Zoo
Tue, Jan 14, 2014 8:04 PM EST