If you wiggle your hand in a sink full of water, you can feel the water motion
you create. A shark senses prey in the distance by detecting water movement
made by fish or other swimming prey. Sharks have a special system, called a
lateral line, that picks up the vibrations in the water. This narrow strip of
sensory cells runs along the sides of the body and into the head. Sharks use the lateral line to detect the erratic motions of sick or wounded
prey (easy-to-catch meals) when they are about three to 10 feet away.
When prey is very close by, a shark can also detect it by bumping up against