A bison was gruesomely boiled to death in a Yellowstone National Park hot spring last week — as tourists watched in horror. The buffalo met its ghastly end when it apparently stumbled into the scalding water at Midway Geyser Basin near Old Faithful, according to the park service. “There were two bison [standing] there,” said Louise Howard, who witnessed the bison’s death during her first-ever visit to Yellowstone, to CBS News. “I thought it was a great photo opportunity.” But the shutter-worthy sight quickly turned tragic when one of the bison stepped into a small part of the basin, then...