Having boldly gone where no polar bear has gone before, a 3-year-old female polar bear was shot dead 250 miles inland in Fort Yukon, Alaska, last week. Hunters who thought they were tracking a grizzly bear shot the polar bear in what they say was self-defense; the U.S. Fish and Wildlife Service is investigating the shooting. Biologists don’t know why the polar bear was so far inland. Anyone want to venture a guess?