Walker's Mammals of the World (Vols 1-2)

Now in its sixth edition and compiled in two volumes, the even larger Mammals of the World contains thorough descriptions of every genus of the class Mammalia known to have lived in the last 5,000 years: 28 orders, 146 families, 1,192 genera, and 4,809 separate species. Volume 1 opens with the monotremes (including echidnas and the duck-billed platypus), which, write Walker and his successor Ronald Nowak, "resemble reptiles and differ from all other mammals in that they lay shell-covered eggs that are incubated and hatched outside of the body of the mother." The first volume then moves on to cover the insectivores, including an astonishing variety of bats, and closes with primates and carnivores. Volume 2 comprises the pinnipeds (seals and sea lions), moves through the cetacea (dolphins, porpoises, and whales) and artiodactyls (deer and their kin), and closes with a huge roster of rodents. It also contains an extensive bibliography numbering some 6,000 items, making the set of inestimable importance to students and professionals.

Many of those mammal species, Nowak writes, are now in jeopardy. The International Union for the Conservation of Nature lists 2,078 threatened species, an increase of 1,661 species over its first list, published in 1987. At the same time, Nowak adds, the U.S. Department of Interior list has grown by only 17 species, for, he continues, "The USDI classification process has become hopelessly subject to delay and manipulation by bureaucratic, political, and commercial interests." He argues that much greater effort needs to be given to protecting these animal citizens everywhere in the world. The knowledge of them that this extraordinary compilation affords is a start. --Gregory McNamee