Book review

Abstract

This slim (155 pages of main text), hard-backed volume is a comparative study of renal anatomy and physiology in different vertebrate classes from agnatha to mammals. It is intended, in the author's words, ‘for students, teachers and researchers’ and the author has judged the level very well. The production of the book is generally good, although better editing would have prevented frequent misspellings and typographical mistakes. Hans Ditrich deserves to be congratulated for writing in a clear, readable and witty style, which makes the impressive scholarship of the book's contents accessible even to a non-specialist reader. The book begins with an introduction, which sets out the basic features of vertebrate renal physiology and which leads naturally to the following chapter on the basic cellular components of renal tissues. From chapter 3 onwards, the book is organized into sections that consider the kidneys of vertebrates, class by class. These chapters are ordered not by phylogenetic progression, but rather by complexity, so that cyclostomes (lampreys etc.) appear after both elasmobranchs (sharks etc.) and osteichthyans (bony fish). From there, the chapters on amphibians, reptiles, birds and mammals follow a conventional progression. The book is illustrated mainly by a mixture of line drawings and micrographs, including some staggeringly beautiful scanning electron micrographs of glomeruli. There were places, though, at which a few more line drawings of different species’ kidneys would have been a great help. The material covered is strongly anatomical and distinctly non-molecular; molecules are occasionally mentioned in connection with physiology, but comparison of patterns of gene expression in different species is left to other authors. This is both a strength and a weakness. The strength of a classically anatomical approach is that different vertebrate classes can be covered in similar detail, without the concentration on one or two model organisms that occurs whenever genes are discussed. The weakness is obviously that the wealth of information that can be provided by comparative genetics is absent, and different kidneys are therefore compared only on the grounds of anatomy and physiology, which are less powerful methods to determine whether cell types from different animals are really homologous, analogous or completely different. Development is also covered only in passing, although a basic knowledge of renal ontogeny is probably taken for granted by the author because some comments about adult anatomy would be difficult to interpret without this. Some of the comments that are made about development contain minor errors (such as the origin of the mammalian ureter). Another real strength of the author's approach is the frequent reference to the other body systems that play a role in water and ion excretion/conservation. This stress that the kidneys do not function in physiological isolation, and that in fish (for example), other tissues may take over some functions that human physiologists think of as renal, making different types of kidney much more logical and easy to understand. The range of vertebrate renal anatomies explained in the book was much greater than I had imagined, and I was again reminded of the way in which our concentration on a few model species carries a price; we may be able to see deep molecular mechanisms using our mice, frogs and zebrafish, but we see them through a tunnel vision that becomes so familiar that it is easy to forget the fascinating landscape of the rest of the animal kingdom. The main competitor to this book would probably be The Kidney (Vize et al. (eds), Academic Press, 2003, £110). The Vize et al. book is very much of the molecular age and covers renal development and adult anatomy in amphibia, birds and mammals. It is not, however, as phylogenetically wide-ranging as Ditrich's book, and being a multi-author volume, does not show the same degree of organization. The two books have quite different purposes and complement each other well; I am glad to have both of them. The two ‘bottom line’ questions a reviewer has to ask of a book are ‘did I enjoy reading it?’ and ‘did I learn anything?’. In this case, the answer to both questions is an emphatic ‘yes’.