Eye #1 Eye #2 Eye #3 Eye #4 Eye #5 Eye #6 Photos: (1) Animals Animals/© W. Gregory Brown; (2) Alan H. Savitzky/Old Dominion University; (3) Animals Animals/© Michael Dick; (4) Visuals Unlimited/© Joe McDonald; (5) Visuals Unlimited/© Brian Rogers; (6) Corbis-Bettmann.