This photo taken on Wednesday, June 3, 2015 of a pamphlet distributed by the National Park Service to people entering Yellowstone National Park warns visitors not to get too close to bison, also known... more 
This photo taken on Wednesday, June 3, 2015 of a pamphlet distributed by the National Park Service to people entering Yellowstone National Park warns visitors not to get too close to bison, also known as buffalo, which can weigh up to 2,000 pounds and sprint three times faster than a person. Despite such warnings, bison have gored two Yellowstone tourists within the past three weeks. (AP Photo/Mead Gruver) less 
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Associated Press | Photo By Mead Gruver
Wed, Jun 3, 2015 12:00 PM EDT