Ronald M. Nowak is the author of the fifth and sixth editions of Walker's Mammals of the World. His other works on mammalogy include North American Quaternary Canis and several sections in the National Geographic Society's Wild Animals of North America, for which he also was editorial consultant. He was staff mammalogist at the former Office of Endangered Species, U.S. Fish and Wildlife Service, from 1974 to 1987.

Authoritative and engaging, this volume from the "Walker's Mammals" series focuses on marsupials, pouched animals whose unusual method of reproduction - between egg laying and placental birth - places them in a unique category among mammals. A comprehensive guide to the biology and distribution of marsupials, this book includes common and scientific names, size and physical traits, habitat and ecology, behavior and social interactions, reproduction, life span, and conservation. The text is coupled with illustrations from the collections of leading photographers and the world's greatest museums. An introduction by marsupial expert Christopher R. Dickman describes the evolution and current status of marsupials and reveals why they add so much intrigue to the natural world.