A horse-drawn carriage operator waits for riders near Central Park in New York on October 20, 2014. Mayor Bill de Blasio is backing legislation that would ban such carriages in 2016. JEWEL SAMAD/AFP/Getty Images hide caption

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Trainer Jimmy McConnell of Shelbyville, Tenn., rides champion walking horse Watch It Now before a 2009 football game in Knoxville, Tenn. Celebrations of the breed's distinctive gait are a 75-year-old tradition, but animal rights activists say that for many of those decades, the walking horse industry has abused animals to get their knees even higher. Wade Payne/AP hide caption

itoggle caption Wade Payne/AP

An elephant at the Emmen, Netherlands, zoo stands at the edge of a ditch in 2009, a day after another elephant fell into the ditch and died. Olaf Kraak/AFP/Getty Images hide caption

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