1. Demographic and environmental stochasticity -- 2. Extinction dynamics -- 3. Age structure -- 4. Spatial structure -- 5. Population viability analysis -- 6. Sustainable harvesting -- 7. Species diversity -- 8. Community dynamics.

The theme of the book is the distribution and abundance of organisms in space and time. The core of the book lies in how local births and deaths are tied to emigration and immigration processes, and how environmental variability at different scales affects population dynamics with stochastic processes and spatial structure and shows how elementary analytical tools can be used to understand population fluctuations, synchrony, processes underlying range distributions and community structure and species coexistence. The book also shows how spatial population dynamics models can be used to understand life history evolution and aspects of evolutionary game theory. Although primarily based on analytical and numerical analyses of spatial population processes, data from several study systems are also dealt with.

In the summer of 1993, twenty-six graduate and postdoctoral stu dents and fourteen lecturers converged on Cornell University for a summer school devoted to structured-population models. This school was one of a series to address concepts cutting across the traditional boundaries separating terrestrial, marine, and freshwa ter ecology. Earlier schools resulted in the books Patch Dynamics (S. A. Levin, T. M. Powell & J. H. Steele, eds., Springer-Verlag, Berlin, 1993) and Ecological Time Series (T. M. Powell & J. H. Steele, eds., Chapman and Hall, New York, 1995); a book on food webs is in preparation. Models of population structure (differences among individuals due to age, size, developmental stage, spatial location, or genotype) have an important place in studies of all three kinds of ecosystem. In choosing the participants and lecturers for the school, we se lected for diversity-biologists who knew some mathematics and mathematicians who knew some biology, field biologists sobered by encounters with messy data and theoreticians intoxicated by the elegance of the underlying mathematics, people concerned with long-term evolutionary problems and people concerned with the acute crises of conservation biology. For four weeks, these perspec tives swirled in discussions that started in the lecture hall and carried on into the sweltering Ithaca night. Diversity mayor may not increase stability, but it surely makes things interesting.

• • • John Harper • • • Nature conservation has changed from an idealistic philosophy to a serious technology. Ecology, the science that underpins the technol ogy of conservation, is still too immature to provide all the wisdom that it must. It is arguable that the desire to conserve nature will in itself force the discipline of ecology to identify fundamental prob lems in its scientific goals and methods. In return, ecologists may be able to offer some insights that make conservation more practicable (Harper 1987). The idea that nature (species or communities) is worth preserv ing rests on several fundamental arguments, particularly the argu ment of nostalgia and the argument of human benefit and need. Nostalgia, of course, is a powerful emotion. With some notable ex ceptions, there is usually a feeling of dismay at a change in the sta tus quo, whether it be the loss of a place in the country for walking or rambling, the loss of a painting or architectural monument, or that one will never again have the chance to see a particular species of bird or plant.

Animal population ecology comprises the study of variations, regulation, and interactions of animal populations. This book discusses the fundamental notions and findings of animal populations on which most of the ecological studies are based. In particular, the author selects the logistic law of population growth, the nature of competition, sociality as an antithesis of competition, the mechanism underlying the regulation of populations, predator-prey interaction processes, and interactions among closely related species competing over essential resources. These are the notions that are considered to be well-established facts or principles and are regularly taught at ecology classes or introduced in standard textbooks. However, the author demonstrates that these notions are still inadequately understood, or even misunderstood, creating myths that would misguide ecologists in carrying out their studies. He delves deeply into those notions to reveal their real nature and draws a road map to the future development of ecology.

Allee effects are relevant to biologists who study rarity, and to conservationists and managers who try and protect endangered populations. This book provides an overview of the Allee effect, the mechanisms which drive it and its consequences for population dynamics, evolution and conservation.