With lively illustrations, poems, riddles, jokes, and interesting facts, Loreen Leedy takes readers on a prehistoric tour beginning with the formation of Earth 4.5 billion years ago. Readers will learn about the plants and animals in each period up to when dinosaurs and small mammals and even humans appeared. There's a timeline that helps clarify the different periods covered, and kids will especially enjoy the entertaining and captioned artwork, humor and intriguing informational tidbits throughout. A fascinating introduction to prehistoric times that will wet readers' appetite for more.