Lynda Petri, age 15, of Peoria, Illinois, for her question:

Where do gerbils come from?

Nowadays, the mousy little gerbils are popular pets. They feel happily at home here, though this is not their native land. Their ancestors belonged to certain dry, sandy stretches of Africa and Asia. Large colonies of their wild relatives still enjoy life in arid regions of southwest Asia and northern Africa. Water shortages do not bother gerbils because they drink very little and cunningly plug, up their tunnels to keep the downstairs from becoming too dry.

A pet gerbil looks like a sizeable mouse, but his long tail ends with a tuft of fur. He hops about like a miniature kangaroo. The little pet loves people and likes to show off his playful games, day or night. However, his wild ancestors stay in their burrows all day and do their hunting and playing after dark. They dine on stores of seeds and grain. Mrs. Gerbil may give birth to a litter of four babies and repeat the performance Every month or so. Gerbils can be very destructive pests of grain crops and some states like California don't let even pet gerbils across their borders.