Tracie Fogel, age 10, of Atlanta, Ga., for her question:

DO FISHES BLINK?

A fish looks through his watery world with a steady stare. You will never see him blink his round, shiny eyes. He keeps that stare all through his life and even after he is dead. Some people think he cannot blink because he has no eyelids, but this is not so. He has special, see through eyelids and a special reason for not blinking.

When drivers go underwater, they wear goggles to protect their eyes from floating debris. If a fish had eyes like ours, this sort of thing would be a big problem. However, his eyelids are designed to protect him. They are made of clear, glassy skin. He can see right through them, so he has no reason to blink. In fact, he cannot blink because his transparent eyelids are permanently sealed over his eyes.