Patti Bryson, age 12, of Houston, Texas, for her question:

Why does an ostrich bury her eggs in the sand?

We all know that there is no reason why an ostrich should hide her head in the sand    and besides the notion is ridiculous. But there are sensible reasons why she should lay her eggs in the sand. A nest in a tree would be ridiculous. After all, she stands six feet tall and weighs more than 200 pounds    besides which, even if her neighborhood abounded in trees, she could not fly up into the branches. Obviously, the logical place for her nest is on the ground. And on her African plains the ground happens to be warm and sandy.

Usually she shares her husband with several other females. And the handsome fellow scoops out the large, shallow nest in the sand. The average ostrich egg is six inches wide and weighs three pounds. Each female lays perhaps ten    and the nest tends to get rather full. The sunny sand is warm, but the plumed ladies squabble for the privilege of sitting on them, at least during the day. At night the proud father shoos them away and nestles down to add his own feathery warmth.