Vision
A shark has excellent vision. In fact, its eyes are about ten times more
sensitive to light than your eyes. Some experiments show that sharks can see
colors, and that they may prefer bright or shiny objects. (Keep this in mind
the next time you shop for a swimsuit!)
Most sharks see their prey when it's about 21-30 m (70-100 ft) away. To protect their eyes from a thrashing victim, some sharks (such as tiger sharks) cover their eyes with a lid, while others (such as white sharks) simply roll their eyes back into the sockets.