The ecology of recently deglaciated terrain

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bolide impact, the terminal Cretaceous, and one related to declining global temperatures, the end Eocene. Understanding of both events has been advanced in large measure by refined geochronology and correlation; the more finely we parse time and space, the more confident we are in wresting causation from the fossil record. Although this book is a major resource for any paleontologist or earth historian working on the midTertiary, it should also be read by ecologists and evolutionists who are interested in the origins of ‘modern’ environments and ecological interactions, and by anyone who cites studies of extinction, climate change, and the connections between them. Unfortunately, the book is tailored more to the specialists than the audience that needs to read it most. It is frustrating that in a book about global temperature change and its biotic effects there is little attempt to relate history to our current concerns about global environmental change. This absence en-

Holocene communities may be more specific to our time than we realize. As concern over human-induced global change increases, it is more important than ever to integrate paleontology with studies of ecological mechanisms and extant systems. Earth historians are the only ones who can examine environmental changes that are of the same scale as those our species is currently generating; they cannot afford to shrink from the task of interpreting as well as recounting the history of global change.

courages the belief that rules about process cannot be drawn from an historical record; in the words of the ISth-century social theorist John Ruskin, ‘There is no law of history any more than of a kaleidoscope.’ The idea that history is uninterpretable is already too much accepted by ecologists steeped in an experimentalist paradigm that disparages the ‘poverty of historicism’. The history of life is full of particularities and contingencies that make generalization difficult, but there are several reasons why it should be part of the study of global change. First, if we are interested in current ecological patterns, we need to know the historical particularities that were involved in their origin, as well as the conditions that maintain them. Second, evolutionary responses to environmental change can only be studied in the fossil record. Third, the last 2 million years have been a period of drastic climatic fluctuations atypical of most of earth history; putative generalizations about ecological process based on living and

Science 231,833-836 2 Wolfe, J.A. and Hopkins, D.M. (1967) in Tertiary Correlation and Climatic Changes in the Pacific (Hatai, K., ed.), pp. 67-76, Sasaki Printing and Publishing 3 Stanley, S.M. (1984) Geology 12,206-208

ance to the historians of ecology than to the modern GIS-wielding warriors of global change. Nevertheless, spatial and temporal vegetational patterns continue to hold ecologists spellbound as they search for explanations and for the laws that govern such processes. Retreating glaciers have served as important laboratories for successional theory since the pioneering work of Cooper’-3 at Glacier Bay, Alaska and the classical work of Cracker and Major4 at this same site. Glacier Bay and similar areas continue to be the focus of many ecological studies, particularly in Europe and North America. The Ecology of Recently Deglaciated Terrain will prove useful to students of succession and indispensable to anyone with an interest in the ecology of glacier forelands (areas recently exposed by retreating glaciers). This book is a unique and encyclopedic compilation of literature and information applicable to the study of vegetational processes and landscape ecology in relation to glaciers. The range of topics and vast amount of literature condensed into the narrative make this an extremely useful reference volume. Integration of the abundant information in this book is conservative,

and the volume mainly chronicles various approaches rather than strives for a new synthesis. The relevance of glacier forelands to successional and geoecological studies is Matthews’ central thesis. For the most part this message is already a classical theme of ecology, and his readers will hardly have to be convinced of this point of view. The depth and breadth of coverage in this book, however, add a new credibility to the importance of these special places as long term ecological experiments awaiting interpretation. It belongs in all university libraries and on the bookshelves of vegetation scientists and geomorphologists. The book could be used as a text for an advanced course, but students are likely to be frustrated (as was I) by the lack of a glossary. The text draws from a variety of geological and ecological fields and liberally uses the associated jargon. Sometimes terms are defined in context, but treatment of terminology is uneven, with illusive terms often used without definition in the same sections where seemingly elementary terms are defined. Perhaps the greatest value of the book to vegetation ecologists is the admirable integration of European

Scott 1. Wing Dept of Paleobiology,National Museumof Natural History,SmithsonianInstitution, Washington,DC20560,USA References 1 Raup, D.M. and Sepkoski, J.J. (1986)

Glaciers and Natural Longterm Ecological Experimenb The Ecology of Recently Deglaciated Terrain by John A. Matthews, Cambridge University Press (Cambridge Studies in Ecology), 1992. $12O.OO/f60.00 ISBN 0 521 hbk (xvii + 386 pages) 36109 5 Studies of vegetational succession have played a key role throughout this century in the development of ecological thinking. Despite the long history and central importance of this concept to ecology, its theoretical status has remained controversial. Succession as an ecological generalization has utility in the interpretation and management of lands, and the concept lends an air of predictive capacity (albeit inductive) to an otherwise largely descriptive science, but faced with the conundrum of multiple underlying mechanisms, students of succession have made little progress formalizing successional theory. Clementsian and Gleasonian views no longer dominate the coffee-break discussions of ecology professors and their graduate students, and the ideas of facilitation and tolerance as driving forces in succession, like the importance of coffee-breaks themselves, seem to be assuming more import190

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and North American examples and literature. Matthews’ experiences in Norway have clearly contributed to the quality of this fine book. For the many ecologists who are currently concerned with issues of global change, it adds a useful perspective to discussions of change in ecosystems. The study of glacier forelands is likely to become a more focused discipline because of this book, and it may be through Matthews’ geoecological approach that the devel-

opment of successional proceed.

theory

will

Kim M. Peterson Dept of Biological Science, University of Alaska Anchorage, Anchorage, AK 99508, USA References 1 Cooper, W.S. (1923) Eco/ogy4,93-128 2 Cooper, W.S. (1923) Ecology 4,223-246 3 Cooper, W.S. (1923) Ecology 4,355-365 4 Cracker, R.L. and Major, J. (1955) J. Ecol. 43,427-448

Mediterranean Vegetation The Ecology of Fynbos: Nutrients, Fire and Diversity edited by Richard Cowling, Oxford University Press, 1992. R62.50 hbk (xi + 4 11 pages) ISBN 0 19 570661 7 Fynbos is the local name for one of the shrub-dominated vegetation types in Cape region of South Africa. As Peter Grubb notes in his introduction to this volume, it is known to the ‘average well-informed ecologist’ because of the richness of its flora and the nutrient poverty of its soils. Horticulturalists will be aware that many of the most spectacular cultivated plants are from the Cape. Like the shrub vegetation of other Mediterranean-climate regions, the fynbos is subject to recurrent fires. It is the last property of the subtitle, the diversity, that particularly recommends this book over the average well-written treatise on a local vegetation type. The facts, as laid out in early chapters, are impressive. With 8550 species of higher plants in 90000 km*, the Cape Floristic region has diversity comparable to or greater than roughly equal-sized areas in the species-rich tropical regions of Central America, Malaysia and Africa. Plant endemism is extraordinarily high. The plant species richness of the Cape is far greater than that of climatically similar areas in California, Chile and the Mediterranean region, although southwest Australia also has high endemism and high species diversity. Southwest Australia is also a region of nutrient-deficient sandy soils with floristic ties to South Africa. The high species richness of the fynbos results from only moderate levels of local (alpha) diversity with very high levels of species turnover from habitat to habitat (beta diversity) and of floras along geographical gradients. The high species richness in the fynbos is the implicit leitmotif of the volume, and the question of what

accounts for it or how to preserve it is at least in the background of most of the chapters. One possibility is that species richness is high because interactions in the fynbos are in some way unique. This is considered in one of the more ambitious chapters by Bond, Cowling and Richards that discusses research on competition and coexistence. The authors argue that ‘classical’ niche theory would suggest that the coexistence of similar species is due to differentiation in resource use, or, in Grubb’s extension of the theory, specialization in regeneration niche. Cody’s data and some data newly collected on leaf traits of species in stands with and without congeners are presented as evidence for character displacement in proteoid shrubs. This supports the concept that species are sensitive to competitive effects, and that community assembly is a fine-tuned evolutionary process. Lottery models are considered at some length; the argument is advanced that resprouting and reseeding of sites after fires provide an analog of the so-called storage effect critical to the lottery process. A simple simulation model provides evidence that similarity of species favors coexistence, but here too the authors draw back from the logical precipice by conceding that either re-invasion from refuges or a rare-species advantage is probably necessary to explain coexistence. Finally, the possibility that coexistence is due to abiotic specializations is explored by citing experiments in progress on species pairs occurring on contrasting substrates. These studies show species surviving well on foreign substrates, suggesting that critical factors such as competition, differential herbivory, or size or age-related abiotic stress become operative later in the life history. Since the poverty of the soils sets the fynbos apart from most other temperate areas and from other less rich vegetation types in the Cape

region, it is an obvious factor to be considered in explaining the high species richness of the area. However, Cowling, Holmes and Rebel0 observe that the available data do not provide strong support for any connection. Some studies have shown no correlation between soil fertility and species richness. Other studies have found such a relation, but in circumstances where the effects of moisture could not be cleanly separated from those of nutrients. Failure to find support for the deficiency-diversity relationship may not be surprising since these models are based on the expected results of plant-plant competition, and therefore cannot account for the high beta diversity, the prevalence of edaphic endemism, and the highly speciose groups such as Eriw and the Proteaceae. Fynbos cannot be discussed without considering fire. Vegetation that has escaped burning for 25 years is considered ancient, and the plants of the fynbos show clear evidence of a long evolutionary coexistence with fire. More than in other Mediterraneanclimate regions (except Australia), germination and establishment depend on fire. One might expect a particularly well-developed capacity for shrubs to resprout after fire, but the striking pattern is the large number of species that are killed by fire and regenerate from seed. Of these, a large proportion are serotinous, retaining seeds on the plant and dispersing them only after fire. The fact that the families and genera with a high percentage of serotinous and nonsprouting species also are species-rich suggests a positive relation between fire adaptation and speciation, a relationship also suspected in California. Similarly strong evidence of fire adaptation is shown by the many bulbous or cormous geophyte species whose flowering is stimulated by fire. A large part of the data on which this book is based were the result of an organized effort to study the fynbos biome that was stimulated by the International Biological Program (IBP). But those who are looking for IBPstyle mega-models and a system simulation synthesis will be disappointed. Huntley, in his introductory chapter, makes no apologies, arguing that by ‘avoiding the dogma of the 1970’s’ the loosely-knit structure of the fynbos project emphasizing community and population level studies was spared ‘the stultifying effect of an ecosystem analysis model on the IBP’. The ecosystem view is not avoided entirely, however. A chapter by Stock and Allsopp considers primary productivity and nutrient cycling, and even 191