Lucinda Howard, age 10, of Huntsville, Alabama, for her question:

Did Australia have an Ice Age?

The Ice Ages that scraped and clawed the surface of North America occurred during the last million years or so. This is a mere blink in the long history of the earth. In the distant past, other Ice Ages have attacked other parts of the earth. Traces of their icy claw marks can be found on rocks formed ages ago. Deep gouges in ancient valleys, piles of shifted gravel and other debris could have been done only by monstrous glaciers. There is a lot of evidence of this sort in the rocks of the earth's crust. The earliest Ice Age we know about occurred about 500 million years ago.

A much later Ice Age occurred about 200 million years ago. And, of all things, its   tremendous glaciers spread through the regions that are now our warm, tropical zones. They formed wide icy belts around the equator, spread across Africa, India and South America. And glaciers of this Ice Age of 200 million years ago also formed in Australia.