. . . "The Bony fishes" . . . . . . . . . . . "In waters of any temperature in the world, from volcanic springs to coldest waters, bony fish have developed ways of swimming to harvest food. David Attenborough examines the role of fins. He explores the open sea with an aqualung to show how fish have developed shapes for survival and travels to the deep seas in a submersible to show how fishes have adapted there." . . . .