The Classifying Animals series welcomes you to the world of classification, in which about 2 million different organisms have been identified and sorted into groups. This appealing and attractive book looks at the classes of fish, and the orders, families and species within them. Find out about the characteristics that distinguish the fish in different groups. Compare the differences in their life cycles. Discover the various ways in which fish have adapted to life in different climates and habitats, from the shallowest streams to the deepest ocean depths.