To capture life a net is required

Mark Pagel finds 20 volumes too slim for a project that, cleverly, expands online.

This new Encyclopedia of Life Sciences is an audacious attempt to produce a comprehensive collection of information on topics in biochemistry, cell and developmental biology, clinical medicine, the diversity of life, ecology, evolution, genetics, the history and philosophy of science, immunology, microbiology, molecular biology, neuroscience, plant science, structural biology, and virology. The publicity material trumpets its 3,000 entries from 5,000 authors running to 12 million words, accompanied by 6,000 illustrations, and all packed into 20 printed volumes.

The project was conceived in 1995 and commissioning of articles began in 1997. Since then, the parent company of the Nature Publishing Group, Macmillan, has used its Nature series of titles to herald the evolution and development, and now birth of this massive project. Not surprisingly, there is widespread curiosity about just how the project has turned out: who will use the encyclopedia and what are its contents like? How will it evolve, and what effect will it have on scholarship?

First, the contents. The encyclopedia describes itself as the "most comprehensive reference source ever published in the biological sciences". Of greater interest than the claim to be comprehensive is the quiet way in which this description narrows the encyclopedia's scope. This narrowing is accurate, as the contents show that the commissioning editors placed far greater emphasis on covering the biological and genetical sciences than on other traditional life-science topics, including clinical medicine, psychiatry and psychology.

For example, the encyclopedia includes about 850 articles on biochemistry, cell biology, molecular biology and genetics. Fourteen sub-categories of article are indexed under biochemistry alone, including biomolecular interactions and biomolecules, articles on DNA metabolism and DNA replication and recombination, intracellular and extracellular signalling and protein synthesis. Each of these sub-categories, in turn, comprises a further set of articles. Similar attention is paid to microbiology, neuroscience, virology and immunology. This is sound coverage with considerable depth, even if not "comprehensive" coverage - a recent encyclopedia of genetics alone contains roughly 1,500 entries.

By comparison, coverage of clinical medicine and related fields is very much of an introductory nature, with just 230 articles devoted to them. Only two articles discuss alcohol and drug-related disorders, 12 consider aspects of cardiovascular disease, 16 describe blood disorders, and just four report on dementias. Each of these topics constitutes a large field of research in its own right, accounting for hundreds or perhaps thousands of research articles a year. I could not find articles on Creutzfeldt-Jakob disease or on the human variants of BSE, both of which cause severe dementias leading to death. There is only very limited coverage of psychology, a surprising omission as the interface between psychology and neuroscience is producing fascinating data.

But in general, Macmillan's decision to emphasise biology and genetics was probably wise, as clinical medicine is an impossibly large topic and does not have the general appeal of genetics or biology. Also, it is, to a large extent, developments in the biological and genetical sciences that are driving the life sciences. Large-scale genomics projects such as the Human Genome Project are typically run by biologists and geneticists. The results of these projects are beginning to affect clinical practice via the identification of clinical disorders caused by defects to single genes. Similarly, developmental biologists are often among the leaders in cloning and stem-cell research, topics with considerable implications for medicine and biotechnology.

So who will read this encyclopedia? The intended audience includes everyone from advanced high-school pupils, through university and postgraduate readers, scientists and other researchers. This is achieved by including three categories of article. To quote the publishers: "Introductory articles are aimed at undergraduates and non-specialist readers. Secondary articles are aimed at advanced undergraduates, graduates and researchers. Special essays provide a forum for key and controversial issues in research, and topics which have a far-reaching impact in society."

Whatever the category, the articles are clearly written and are well supported by tables, figures and lists of further reading. Some 1,400 articles are described as introductory, and there are 50 special essays. Both categories of article live up to their definitions. The remaining 1,850 entries are secondary articles. They consistently provide readable accounts and, in the main, are not deeply technical. The writing tends to be quick paced, presenting much material as fact with limited discussion. Advanced high-school to advanced undergraduate students will be able to use the secondary articles, although both groups may wish to augment them with introductory material. Graduates and researchers will be able to gain from them introductions to advanced topics.

The level of coverage of the secondary articles can be variable, and sometimes authors' points of view intrude. For example, Steven Rose's article on the origins of life downplays the primacy of nucleic acid-based replicators, and Rose ignores the exciting work of the Nobel prizewinning scientist Tomas Cech. Cech's discovery of pieces of RNA that could spontaneously act as enzymes provided a crucial element to understanding the origin of life. Rose's views on this subject do not reflect the consensus in this area.

Of course, in a work of this size it will always be possible to find aspects with which one disagrees, and I should emphasise that the example mentioned here does not characterise the whole. But the wider point is that one should use such an inclusive reference work intelligently, consulting its further reading along with other outside work.

What about its relationship to other encyclopedias? Seeing these volumes lined up on a shelf immediately calls to mind those venerable encylopaedias of one's youth such as the Encyclopedia Britannica or the World Book . But the Encyclopedia of Life Sciences , by virtue of being more focused than either of these other works, achieves greater depth of coverage. And this is important because the explosive growth of scientific information means that there is little room for general works. It also means that specialist topical scientific encyclopedias of an even narrower focus are increasingly in demand. There are, for example, encyclopedias of climate change, evolution, ecology and genetics, and others are in development.

Does the Encyclopedia of Life Sciences see itself as a replacement for these other more topical scientific encyclopedias? If so, I do not think it succeeds, although as the editor-in-chief of one such encyclopedia, it is only fair to acknowledge my potential conflict of interest. Despite its impressive breadth, the Encyclopedia of Life Sciences does not provide the in-depth coverage of, say, ecology, that one would expect of an ecology textbook or of an encyclopedia of ecology. The problem is that the life sciences are quite simply too vast to be put under even 20 roofs.

A more realistic claim is that this encyclopedia serves a different role, that of providing a broader sweep than any other single encyclopedia and at a depth that provides useful coverage of a broad range of fields. In this, it succeeds but the question must then arise among librarians of high-school and university libraries as to whether they might prefer a selection of topical encyclopedias to one large one?

Finally, evolution. In some important respects it is pointless and unfair to review only this 20-volume set because of the existence of the els.net . Discoveries and technological advances in several important sub-fields of the life sciences are being made at breathtaking rates, thereby re-writing or creating de novo whole new fields. Fields such as proteomics, transcriptomics, metabolomics, protein structure prediction and biotechnology feature only minimally, if at all, in the encyclopedia. And yet, it is in these still relatively unknown fields that huge advances will be made over the next ten years. Given this, those at the helm of the Nature Publishing Group would have to be made of either very stern or foolish stuff to stake this enterprise on a static set of books.

And they have not. The els.net is an electronic version of the 20 volumes, but it is Macmillan's intention to make it a dynamic and continuously updated catalogue and online resource. Seen in this light, the book is the poor relation of the website, an obvious loss-leader designed to get the project going, trading on our predisposition to think of an encyclopedia as a tangible entity we can hold in our hands. Macmillan is showing itself to be a gutsy and forward-looking publisher, almost single-handedly making a bid to define the course of reference publishing, and vigorously attempting to wean scientific readers off traditional library material in favour of web-based materials.

Using the web in this way potentially makes more material available to a wider audience than ever before. This must be a good thing. It also places Macmillan in a powerful position, as the els.net could lead to the "Encarta-isation" of science information.

At the moment, there is no worry about this happening, and Macmillan can be rightly proud of the quality of its science publishing. What remains to be seen is just how dedicated Macmillan will be to updating the els.net ; how easy it will be to persuade authors to contribute; to what extent people will flock to the net as a means of acquiring information; and whether libraries will wish to pay for it (£1,500 a year for a nine-user online subscription). If it all works, the els.net has the potential to be a truly comprehensive encyclopedia of the biological and life sciences.

Mark Pagel is professor of evolutionary biology, University of Reading, and editor-in-chief of Oxford University Press's Encyclopedia of Evolution .