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Antarctic fish Biology: Evolution in a Unique Environment, Joseph Eastman Academic Press, Inc., New York, (1993). 322 pages. $74.95. ISBN 0 12 228140 3.

As the sub title of Eastman’s new volume on Antarctic fishes suggests, the Southern Ocean, indeed, is a unique environment from both oceanographic and ichthyological perspectives. It is vast, accounting for approximately 10% of the planet’s marine environment. Species diversity of its fish fauna is unusually low compared to other ocean systems, containing only about 1% of the world’s known fishes and dominated by a single suborder, the notothenioids. Waters south of the Antarctic Convergence are a distinctive environment because of their long (>25 m.y.) isolation, stable and severely cold temperature and the unusual hydrogeology surrounding Antarctica. Eastman has exploited all of these characteristics and our growing but still incomplete knowledge of Antarctic fishes to produce a very thoughtful treatise on their biology. But above all, it is a book about evolutionary biology and the physical and biotic forces that shape the process. It is the type of work that can be produced only by a single author and Eastman’s expertize in morphology and systematics, plus his understanding of physiology and ecology, make him exceptionally well-suited to the task. The book logically is divided into three major parts. The first, “Physical and Biological Characteristics of the Antarctic Marine Environment”, includes admirable primers on the climatic, geological and oceanographical characteristics of the continent and their histories. It also incorporates a section relating the fossil record of Antarctic fishes to the geological and climatic histories of the continent. The second section focuses upon a description of life histories, systematics and zoogeography of the extant Antarctic fish fauna. The third section is entitled “Organ System Adaptation in Notothenioids”, but really contains as much information on cellular physiology and biochemistry of the group as it does systemic physiology. The most distinctive aspect of the book, setting it apart from other volumes on Antarctic fishes, is that all of these topics consistently are treated throughout the volume within the context of evolutionary questions. For example, Eastman makes a point to emphasize how the limited shallow water habitat of the Antarctic continental shelf has affected evolution of the continent’s fish fauna. Such physiologically related characteristics as the distribution of antifreeze glycopeptides (AFGPs, kidney glomeruli and presence or absence and forms or hemoglobin are mapped on systematic cladograms developed from more traditional morphological data, permitting insight into how and when these characteristics have evolved within the notothenioid suborder and its families. Eastman has done an excellent job of melding quite disparate pieces of information to support the book’s central theme of evolutionary biology. I am particularly impressed with the even-handed consideration of much information on Antarctic fishes that usually is treated from a dogmatically adaptationist viewpoint. Eastman does not hesitate to recognize such characteristics as the presence of AFGPs as clearly adaptive, yet is careful to point out that other unique features of some Antarctic fishes families (e.g. the haemoglobinless condition of the channichthyid icefishes) may well be due to chance mutations or simply phyletic inertia. The overall tone of the book is scholarly, thoughtful and the product is an excellent synthesis of information on the biology of this fascinating group. Yet all of this is presented in a writing style that is lucid, relaxed and easy to read. In his preface, Eastman stated that his goal was “ ... to give the reader an appreciation for the biology of Antarctic fishes and why they hod the interest of those of us who study them I believe that he has achieved that goal admirably and, in the process, produced a book that should appeal to ecologists. Despite my own research experience with Antarctic fishes, I have learned much in my first reading of Eastinan’s book. I suspect that the next reading will yield even more insight. It belongs on the shelf of any serious student of polar biology or evolution.