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ations can also be found in the index. At times Turner also confronts us with many contrasting examples, leaving the reader to wonder what exactly the typical feature or pattern is. In the final chapter Turner discusses a classification of TRF trees into functional groups. Such a classification is useful, as the high diversity of the many tropical forests not only bedazzles us as observers but also hampers many statistical and modelling approaches – diversity is a mixed blessing. The approach used here to arrive at functional groups is based mainly on gap dynamics of the forest and the trees that may have specialised on specific stages of the regenerating forest – in short: the pioneer and climax species. His conclusion here is not very surprising, and supports the concept of the existence of a pioneer-climax axis among the species. There is little support for discrete clustering. I found this a bit disappointing – not because I had expected discrete clustering – but because of the single axis approach. A researcher working on nutrient limitation will classify his trees differently than between pioneers and climax species. In fact Turner does give such a classification earlier in the book. In other words a functional classification depends a lot on the interest of the researcher. It would be interesting to see if there is any overlap between different functional groupings. My gut feeling is that many classifications will be shown to be independent of each other, which does not lead to a strong further simplification. Hence the functional grouping used should depend on the question a researcher wants to answer. For forest dynamics the pioneer – climax continuum is a good choice; for other research models it will not suffice. Despite these few points of criticism, I have read the book with great interest and pleasure and can recommend it to those who would like extensive of background information on tropical rain forest ecology. It will not disappoint, and will certainly be on my desk for a long while. Hans ter Steege Utrecht, The Netherlands

Levey D. J., Silva W. R., Galetti M. (eds.): Seed dispersal and frugivory. Ecology, evolution and conservation. 2 color plates, 1 halftone, 90 line illustrations, 530 pp. CABI Publishing/CAB International, Wallingford New York, 2002. Hardcover £ 75.00, US $ 140.00. ISBN 0-85199-525-X. Plant-animal interactions is one of those topics that intrinsically captures the attention of botanists and zoologists alike, most likely because it reflects our personal fascination with the natural world–the basic reason we became biologists. And there is something appealing about the thought of going out to observe the flora and fauna in the wild, watching bees visiting flowers and birds pecking at luscious fruits, then returning to the lab to test some of the ideas gathered in the field. It is thus gratifying to find, in this day and age of ever-increasing scientific specialization, that the spirit of natural history remains alive and well in the research realm of fruit-frugivore interactions. In the 32 studies published in Seed Dispersal and Frugivory: Ecology, Evolution and Conservation, one can still experience, albeit second-hand, the excitement of making empirical observations and collecting data in the field, for instance, surveying the dietary preferences of wild toucans or assessing the total fruit consumption of maned wolves in the tropics. Of course, it goes without saying that these investigations go beyond mere notes on new occurrences or simple, descriptive case studies; the rigorous application of quantitative methodology and modern technology, experimental testing, as well as the theoretical development of concepts and models are also an integral part of these papers. Seed Dispersal and Frugivory is actually the distillation of papers that were presented at the Third International Symposium-Workshop on Frugivores and Seed Dispersal held in Sa˜o Pedro, Brazil, in August 2000. Published less than a year-and-a-half later, this proceedings volume represents the cutting edge in the field of seed dispersal and frugivory, as well as a tribute to the efforts of the editors and 76

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contributors in getting the 500+ pages of this book published so quickly. The cover of the hardbound book is a merry scene with color photos featuring scarlet berries, dangling blue seeds, and various frugivorous animals in action; there is even an open-mouthed fish leaping out of the water to devour a pendulous fruit. Just inside the cover, a color plate of brightly colored red and blue mimetic fruits greets the reader. Like the avian frugivores enticed to eat up, serving as unwitting vehicles for seed dispersal, we, too, are allured into continuing our reading consumption of this book. The next few pages contain the usual set of acknowledgments, list of contributors to the book, as well as a preface from the editors relating the historical development of fruitfrugivore studies. The extensive subject index bringing up the rear of the volume is especially welcome in a symposium volume. The Englishlanguage text of the included scientific papers is well written, and it is clear that the diligent efforts of Levey et al. have resulted in a cleanly edited and consistently formatted book. Scattered throughout are well produced tables, graphs, and charts. The only departure from the usual layout of topics in each paper is the lack of an abstract; however, it is apparent that the editors intended to present this series of papers as sequential chapters in a book rather than as an unordered collection of papers given at a symposium. Levey et al. have followed the previous editors of this symposium series in grouping the written contributions into five major sections: ‘Historical and Theoretical Perspectives’ (6 papers), ‘Plant Strategies’ (9), ‘Animal Strategies’ (4), ‘Consequences of Seed Dispersal’ (5), and ‘Conservation, Biodiversity and Management’ (8). The average length of the 32 papers is 16 pages. Despite the multitude of study sites, methodologies (although picking out seeds from scat samples seems to be a common approach!), and the choice of fruiting plants and fruit-eating animals as the objects of study, the ultimate target of these investigations is seed dispersal.

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After all, from the point of view of a bioticallydispersed plant, a fruit is a cleverly and attractively packaged receptacle to be used expressly for the dissemination of seeds by animal agents. There is, however, a fine line between use and abuse in this relationship. To be reproductively successful, a plant must somehow ensure that the viability of its seeds will not be destroyed or diminished by the animal’s mastication and digestion, but that the seeds stand a good chance of being deposited in an environment conducive to germination and growth. Until now, most work has focused on frugivorous birds and bats, although it should be kept in mind that some mammals are also consumers of fruits and can serve as longrange seed dispersers as a consequence of their long gut passage times and broad migratory ranges. Even some animals that we intuitively think of as carnivores really like to eat fruit. The maned wolf, Chrysocyon brachyurus, for example, is actually an omnivorous canid that includes many fruits in its diet. In fact, it particularly likes to feed on the large fleshy berries of Solanum lycocarpum, known locally as lobeira or ‘‘wolf’s fruit’’. The paper by Motta-Junior and Martins on the dietary habits of maned wolves in central South America will serve nicely here as a case study from the book which touches on ecological, evolutionary, and conservational aspects, as well as being a fascinating study in itself. Motta-Junior and Martins began by determining the degree of frugivory in the maned wolf by analyzing the frequency of seeds in scat samples. The percentage of fruit biomass in the large canid’s diet ranges from 15 to 57%, varying from site to site, as well as from season to season. The wolf shows a strong and consistent preference for S. lycocarpum at all study sites, indicating that this fruit plays a major role in the wolf’s diet and leaving the authors to ponder whether the occurrence of the maned wolf in Brazil is determined for the most part by the natural occurrence of this solanaceous fruit. The feasibility of the maned wolf as a seed disperser was then tested by examining the

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effect of the wolf’s digestive tract on seed viability. Seeds that were extracted from scat samples were sowed, and the ensuing rates of germination were studied. For the most part, the seeds passed through the digestive tract unscathed; in fact, this gut treatment may be beneficial in removing the germination-inhibiting compounds in the fleshy tissue of some fruits, such as in S. lycocarpum. Motta-Junior and Martins also found some evidence that small-seeded species may be clump-dispersed by the maned wolf, while larger ones are probably scatter-dispersed. The authors then surveyed the preferred habitats of the maned wolf through the analysis of satellite images and found that it prefers the open grassland/savannah-like environments referred to as cerrado in Brazil. After combining habitat data with diet data, they found that this fruit-eating wolf may actually be an important seed dispenser in the cerrado vegetation. In regard to wildlife management, the authors suggest that individuals of this species in captivity are often given a diet too high in protein, which may facilitate the development of cystinuria and gingivitis. MottaJunior and Martins therefore suggest increasing the proportion of fruits in the diet of captive maned wolves to 30–50% of their daily wet mass of food. I found Seed Dispersal and Frugivory as fun to read as it is packed with important scientific information. Researchers on seed dispersal, frugivory, or plant-animal interactions should attempt to get his or her hands on a copy. Furthermore, any biological, botanical, or zoological library would be incomplete without one. Carole T. Gee Bonn, Germany Lurquin P. F.: The Green Phoenix. A history of genetically modified plants. Black and white line illustrations and photographs, 240 pp. Columbia University Press, New York, 2001. Hardcover £ 36.00, US $52.00. ISBN 0-23112262-4

The year 2003 will see the 20th anniversary of the successful genetic manipulation of plants – in other words the creation of transgenic plants, which were reported independently by three research groups from the United States and Belgium in 1983. A book reviewing the history of the scientific developments that led to this great achievement is thus timely and welcome. Paul Lurquin, the author of The Green Phoenix and professor of genetics at Washington State University, has been directly involved in many experimental approaches concerning the transformation of plants with foreign DNA and consequently writes from an insider’s point of view. As with other historical accounts written by scientists, be it The Double Helix by James Watson or The Lac Operon by Benno Mu¨ller-Hill, other actors in the respective fields may, of course, have had other things to say or add. The success of plant transformation is intimately interwoven with the elucidation of a fundamental discovery in biology: the transkingdom transfer of the genetic material DNA from a bacterium to a eukaryote, the green plant. It is part of Agrobacterium tumefacien’s lifestyle to infect plants, cause the growth of undifferentiated plant tumour tissue and genetically re-programme the plant cells to produce substances called opines, which only the bacterium can use as food. As the 1970’s gave way to the 1980’s, many of the molecular mechanisms were being unravelled and the tool kit for using Agrobacterium as a vector to introduce defined genetic material into plants at man’s design and will was being developed. Paul Lurquin tells the story of these scientific developments mainly as they took place in the laboratories of Jeff Schell and Marc van Montagu in Ghent, Belgium and of Mary-Dell Chilton, Gene Nester and Milt Gordon at Washington University, Seattle, in Chapter Three (‘The Crown Gall Breakthrough’) and this is one of the best chapters of the book. As with the rest of the book, however, a somewhat more than basic understanding of molecular biology is needed to follow the unfolding of the story. The book layout is