Rhyming verses followed by factual information briefly describe the sleep habits of a variety of animals.

At bedtime a young girl asks "Does everything in the world go to sleep?"

While other animals sleep at night, some quietly and others noisily, some alone and others huddled together, a wide-eyed owl watches.

Estivation is just like hibernation - only it happens in summer instead of winter. Why do some animals settle into cool, snug spots and sink into a summertime sleep? Because it's too hot for their bodies to function, or their food is in short supply. Some estivating animals sleep groups; others rest alone. Some go on a long journey before they slumber; others hunker down right at home. From the pixie frog to the spotted turtle to the desert hedgehog,...