YELLOWSTONE NATIONAL PARK, Wyo. (AP) — Tourist John Gleason crept through the grass, four small children close behind, inching toward a bull elk with antlers like small trees at the edge of a meadow in Yellowstone National Park. “They’re going to give me a heart attack,” said Gleason’s mother-in-law, Barbara Henry, as the group came within about a dozen yards of the massive animal. The elk’s ears then pricked up, and it eyed the children and Washington state man before leaping up a hillside.