Brenda Allen, age 11, of Visalia, Calif., for her question:

HOW DO TRAPDOOR SPIDERS MAKE THEIR HOMES?

The underground home of the trapdoor spider is an amazing engineering feat. The female begins excavating the burrow by clearning pebbles and other objects away from a circle about an inch and a half wide. Then she digs a tube like hole, smoothing the sides as it deepens with her chisel like fangs and coating them with a delicate but strong filmy web. She constructs the "lid" or trapdoor to her home by moistening bits of earth with "web glue," and fusing them together with webbing for extra strength.

When the door is halfway completed, she pushes it upright and weaves a flexible web hinge. Now she pulls the door down again and continues to build until the opening is closed. Beneath this perfectly fitting door, she vigilantly waits for a passing meal. When she senses the vibrations of an insect overhead, she slips the door up, snags her victim and enjoys a tasty meal. She never completely leaves her snug home because even she would have a hard time finding it. Her eyes are on top of her head, making a thorough search nigh on to impossible.