Some 385 to 360 million years ago, fish came out of the water and began to colonize the land. But how could an aquatic animal, accustomed to swimming, learn to walk on land? To help answer that question, some scientists have turned to a living fish that can do just that: the mudskipper. And it turns out, those strange fish use their tails to navigate difficult terrain, according to new research published Thursday in the journal Science. The mudskipper "captures some of the potential early aspects of the terrestrial locomotors," says Daniel Goldman, a biomechanical physicist at Georgia Institute of Technology and an author on the new paper, in a phone interview with The Christian Science Monitor.