米ワイオミング州などにまたがるイエローストーン国立公園で、酸性の熱水泉に観光客の男性が誤って転落して死亡し、遺体が溶解してなくなる事故が起きた。 A view of a hot spring at the Norris Geyser Basin at Yellowstone National Park on May 12, 2016.Yellowstone, the first National Park in the US and widely held to be the first national park in the world, is known for its wildlife and its many geothermal features. / AFP / MLADEN ANTONOV (Photo credit should read MLADEN ANTONOV/A