Gr 4-6-- A compilation of material that covers such a wide range of subjects that it's hard to know where one would classify it. Atlantis, human evolution, Egyptology, Stonehenge, dinosaurs--they're all here. The book's large size, attractive illustrations, and question-and-answer format make it interesting and informative browsing material. It's less reliable as a reference source, since its coverage is so idiosyncratic; for example, who'd think to look here for the answer to ``How did diseases begin?'' There is a good index, and the information is current. Best used as overview of the history of life on Earth. --Cathryn A. Camper, Minneapolis Pub . Lib .