How Global Warming Caused the Attack of the Giant Ants

It sounds like the opening plot to a made-for-TV horror flick: Global warming renders an Arctic land bridge habitable, spurring a race of "monstrously big ants" to blaze a trail between Europe and America. This particular horror story actually played out 50 million years ago, and the monstrously big ants were only about 2 inches long, about the size of the smallest known hummingbird. Archeologists recently unearthed the fossilized remains of this new giant ant species---one of the largest ant species ever seen---in Wyoming, making it the first complete giant ant fossil found in America. And because similar giant ants have been found in Europe, they think this is the first reported example of a tropical insect traipsing across the Arctic. It all started when paleoentomologist Bruce Archibald spied a fossil that was sitting in a drawer at the Denver Museum of Nature and Science. "I immediately recognized it and ...