Tooted whales, which include killer whales, are predators that feed actively on fish and squid. They possess sharp teeth, usually in both jaws, which they use to catch their prey. Whales generally are torpedo-shaped, with smooth and streamlined bodies. The front limbs of these aquatic mammals are modified into a pair of flippers and primarily are used as stabilizers or steering mechanisms. Primary thrust in locomotion comes from up-and-down movements of the tail and flukes.