An introduction to the evolution and adaptation of amphibians and reptiles, bridging the gulf between the plethora of ''popular'' books and the more advanced texts directed towards the needs of specialist research workers, thus making it accessible to advanced students worldwide. Basic principles are explained in non-technical terms, and the adaptive responses to natural selection which have engendered the diversity of forms that exist in the fossil record and are found in the world today are covered. The book also includes the extinct forms such as dinosaurs, ichthyosaurs and plesiosaurs. In the concluding chapter, relationships with mankind and the preservation of diversity are discussed.