Introduction to the Principles of Plant Taxonomy
Second edition

V.V. Sivarajan (edited by N.K. Robson)

Cambridge University Press, Cambridge. 1991. xiv+292 pp. ISBN 0-521-35679-2.

This book by Sivarajan is explicitly aimed at university undergraduate and postgraduate students undertaking a subject covering plant systematics. It would be completely unsuitable for the general public, as it assumes a fair knowledge of introductory biology, and it is probably even beyond the needs of general botany graduates. As such, it should be expected to meet the criteria specified for this series of reviews, and indeed it does to a large extent. However, there are notable lapses, as we shall see.

The book is a revised version of one originally produced and published in India in 1984, which was reasonably well-received at the time. It has been updated by the author, and then edited by Norman Robson. It is organised into 9 chapters, plus an Epilogue - there are no appendices or other extraneous matter. There are no family descriptions, no list of terminology, and almost no illustrations or tables - this is dense theoretical text from beginning to end. The index is comprehensive enough, including all taxonomic names, and the bibliography is very extensive and mostly up-to-date, being certainly the best of the books reviewed so far. The examples chosen are extremely cosmopolitan, covering all continents (but favouring the northern hemisphere), which is a refreshing change from the parochial books reviewed last time.

Unfortunately, this is the worst-presented scientific book that I've ever seen. I don't even know where to start in describing its presentation, and the publishers should be ashamed of themselves for releasing such a low-quality paperback at this price. Perhaps I could start by pointing out that the editor goes under several names - he is "N.K.B." Robson on the front cover and in the References, but "N.K.P." Robson on the title page and its reverse. This is fairly typical of the rest of the book - if you can't find a mistake of some sort on any one page it's only because you're not looking hard enough. Mistakes range from a rather random number of lines of text per page (some pages end within a few millimetres of the bottom margin) to unexpected uses of English words (the suggestions of the reviewers of the earlier edition are described as "lucrative"), from huge sentences without apparent punctuation to incorrect (or missing) reference citations, from minor typographical errors to inconsistent author abbreviations (Linnaeus goes from "L." to "Linn." in the middle of the very chapter on nomenclature), and from ever-changing spelling to wrong figure references. The list goes on. Scientific books are expensive enough as it is, if for no other reason than the usually small print runs, but this book shows a contempt on the part of the publisher that is beyond the pale. No-one should be expected to pay such a large amount of their hard-earned money for such poor quality - the release of this book is inexcusable.

Nevertheless, the content of the book is the main focus of this review. The aim of the book itself is stated unambiguously several times in the Preface and in the Foreword. For example (page xiii): "In most of our universities what is being taught in the name of the subject is the detailed characters of families specified by the curricula with a number of examples of plant species often not known to the students, thus forcing them to cram hundreds of Latin names without knowing exactly what they refer to. Principles of taxonomy usually get a rough deal in the class rooms. This has eroded the credibility of the subject to a very great extent, often giving the impression that it does not have a sound theoretical foundation and that it means nothing more than telling the names of plant species. As a result, botanists have been fleeing to greener pastures, more fashionable fields of botanical studies, reducing plant taxonomy into an 'esoteric' area of plant research."

Unfortunately, no-one is likely to be attracted to the science of plant taxonomy by this particular book - only pig-headedness got me to the end of it. The book is about the principles (rather than the practice) of systematics, and as such it is a fairly dry and unrelenting exposition of the topic. I read a number of other books between when I started this one and when I finally finished it (including the two books that I reviewed last time), and most of them were much more interesting to read than this one. The writing style is neither pedantic nor otherwise annoying - it is simply relentlessly dry and theoretical. Systematics is interesting as well as scientific, but if the author has any enthusiasm for his subject then he keeps it well hidden.

Nevertheless, the actual content of the book has much to recommend it, although in places the author's personal preferences and opinions overly dominate the discussion. The book starts well, with the Introduction (14 pages) covering the importance and aims of taxonomy simply and effectively. However, no actual "principles" of plant taxonomy are ever enumerated, which belies the title somewhat. Chapter 2 (10 pages) is an interesting history of The Evolution of Theories of Biological Classification, which is certainly not covered in the other books reviewed so far. If nothing else, this chapter provides a lucid exposition of several relevant topics that many taxonomists tend to hide from.

Chapter 3 (39 pages) covers some of the Problems in Evolutionary Taxonomy. This starts well, providing good coverages of the vexing problems of primitive and advanced characters, monophyly and polyphyly, parallelism and convergence, and homology and analogy. The author has clearly followed the current discussions of these topics closely, and he summarizes the current state of the debates effectively.

However, the section entitled "The theoretical basis of plant classification: a critical evaluation" is the section in which the author's own prejudices intrude most. The presentation of cladisitcs, for example, is often misleading, as it cites some questionable statements by some of its proponents as being generally accepted by all cladists. It also ignores the relative ability of the different methodologies to retrieve information from their classifications, and even ignores the relative testability of those classifications. Ultimately, the author seems to find the cladistic arguments theoretically convincing, but he can't quite bring himself to become one in practice. He eventually concludes that phylogeny and taxonomy are incompatible: "Evolutionists would do well to confine their investigation to the evolutionary processes and products, leaving the problems of classification and concepts of taxa to the taxonomists". So, classification becomes merely a pragmatic exercise of trying to intuitively incorporate all of the available data: "The intuitive taxonomist's view, that the power of the human intellect in recognising gestalt as homology and synapomorphy will thus still remain the basis of professional taxonomist's practice, seems to be true." This is tantamount to saying that taxonomy can never be a science.

Chapter 4 (22 pages) is a generally good coverage of The Historical Development of Classificatory Systems, although cladists are described as "the extremists among evolutionary taxonomists", cladistic systems are described as "monothetic", and all recent classification schemes emerge as merely minor modifications of that by Takhtajan. Chapter 5 is an aside (4 pages) on Taxonomic Structure, which could easily have been the introduction to the next chapter.

Chapter 6 (24 pages) discusses Concepts of Taxa, mainly species but including genera and families. The comparison of the various species concepts is generally good, but some of the arguments against particular concepts depend very much on personal points-of-view. Unfortunately, at the higher taxonomic levels the author prefers pragmatism to sound theoretical foundations, and the principles expounded in the Preface don't make it past page 110: "protagonists of this strict genealogical definition of taxa seem to forget that, for people who use this system, the greatest need is to identify, remember and communicate, and that philosophical purity is of no consequence unless it is tempered by dictates of practical convenience and common sense."

Chapter 7 (23 pages) details The Material Basis of Systematics, including characters, speciation and isolation mechanisms. Unfortunately, this is often just a repetition of textbooks from the 1970s, rather than being an up-to-date and critical summary in the vein of the other chapters. Even the other books that I've reviewed mention punctuated equilibria, for example.

Chapter 8, covering Sources of Taxonomic Characters, is the largest chapter (61 pages) and the most boring. It is really just a brief discussion of each of seemingly endless examples of published uses of the various character types (morphology, anatomy, palynology, embryology, cytology, phytochemistry), rather than a comprehensive synthesis and overview. Furthermore, the discussion of DNA and RNA is very out-of-date for a book published in 1991. However, the chapter ends with a section entitled "Modern systematics: the synthesis unachieved", which gives short shrift to any dichotomy between experimental taxonomy and classical taxonomy. However, the author does this by trying to denigrate experimental taxonomy, rather than by highlighting the changes that have occurred in classical taxonomy in the last 20 years. He considers that: "the 'experimental' aspect of taxonomy was obviously part of the 20th century attempt to transform taxonomy into a 'science', since experimentation is widely (and incorrectly) considered to be a sine qua non scientific procedure". Any attempt to turn classical taxonomy into a science seems to me to have its heart in the right place, however misguided the actual attempt.

Chapter 9 (20 pages) is a clear and sensible discourse on Plant Nomenclature, although there are so many typographical errors that I'm not sure how much use it would be to the uninitiated, and the names of varieties are treated as quadrinomials. The practical nature of this chapter also seems somewhat out-of-place with the conceptual issues discussed in the rest of the book.

The book ends with a short (5 page) Epilogue, which considers the current status of plant taxonomy: "My purpose here is only to inspire a soul-searching among ourselves, to understand why taxonomy has come to such a pass." This is my favourite part of the book, although I don't agree with all of what it contains, nor do I think that it covers all of the topic. Still, the author is revealed to be a human being after all, and he really does care about his subject. I would love to quote from it at length, but that must await another day.

In the final analysis, the content of the book doesn't really live up to its promise. There are too many conflicting ideas about what constitutes a science in the different chapters, and pragmatism comes to the fore in too many places for me to be able to recommend this as an effective introduction to plant taxonomy as a modern scientific enterprise. Taxonomy is certainly seen to be more than just biological identification, and more than just a scholarly exercise; but the excitement that the current methodological debates and new techniques should generate is completely absent. Perhaps the problem is that it's generally only older people who have the breadth of knowledge and inclination to write a textbook, while it's generally only the younger people who are able to generate and maintain the necessary enthusiasm; the combination is rare indeed.

David Morrison
Department of Environmental Biology & Horticulture
University of Technology, Sydney

Originally published in Australian Systematic Botany Society Newsletter 72: 24-27 (1992).