There are more than a million different kinds of animals in the world. Only 50,000 of these have backbones, and are called vertebrates. The rest are animals without backbones, called invertebrates. This book gives an overall view of these animals and shows the young reader how to distinguish between the major groups. It was awarded Outstanding Science Book for Children.

There are many books on dinosaurs but this one is special. It is the only book at this age level that teaches the classification of dinosaurs. How is Tyrannosaurus different from a Stegosaurus? What criteria do scientists use to put dinosaurs in separate groups?