Eyewitness DVD: Shark

Why are sharks' teeth always sharp? Which giant shark wasn't discovered by humans until 1976? Shark takes you down into the murky world of sharks and their relatives and reveals what motivates these fascinating creatures. Discover a shark that can fit in your hand and a shark that eats only plankton—and learn that not all sharks are killing machines. This award-winning series features stunning photography and graphics to bring science to life. Closed-captioned.