The first edition of this book, published in 1982 by the University of Queensland Press, established itself as the main introductory textbook on marine parasitology. The second edition has been revised to take account of recent advances and includes an additional chapter on the structure of marine parasite communities. There are also new sections on pollution, translocations of hosts and parasites, and on the effects of parasites on the aquaculture of marine fish, molluscs and crustacea. The chapters covering ecological, zoogeographical and economic aspects have also been significantly changed. Aimed particularly at students and research workers in parasitology and marine biology, the book will also be of interest to ecologists, biologists concerned with zoogeographical problems, and to aquaculturists, fish and fisheries biologists.

Ecology has long been shaped by ideas that stress the sharing of resources and the competition for those resources, and by the assumption that populations and communities typically exist under equilibrium conditions in habitats saturated with both individuals and species. However, much evidence contradicts these assumptions and it is likely that nonequilibrium is much more widespread than might be expected. This book is unique in focusing on nonequilibrium aspects of ecology, providing evidence for nonequilibrium and equilibrium in populations (and metapopulations), in extant communities and in ecological systems over evolutionary time, including nonequilibrium due to recent and present mass extinctions. The assumption that competition is of overriding importance is central to equilibrium ecology, and much space is devoted to its discussion. As communities of some taxa appear to be shaped more by competition than others, an attempt is made to find an explanation for these differences.

Ecology has long been shaped by ideas that stress the sharing of resources and the competition for those resources, and by the assumption that populations and communities typically exist under equilibrium conditions in habitats saturated with both individuals and species. However, much evidence contradicts these assumptions and it is likely that nonequilibrium is much more widespread than might be expected. This book is unique in focusing on nonequilibrium aspects of ecology, providing evidence for nonequilibrium and equilibrium in populations (and metapopulations), in extant communities and in ecological systems over evolutionary time, including nonequilibrium due to recent and present mass extinctions. The assumption that competition is of overriding importance is central to equilibrium ecology, and much space is devoted to its discussion. As communities of some taxa appear to be shaped more by competition than others, an attempt is made to find an explanation for these differences.

It is clear that nature is undergoing rapid changes as a result of human activities such as industry, agriculture, travel, fisheries and urbanisation. What effects do these activities have? Are they disturbing equilibria in ecological populations and communities, thus upsetting the balance of nature, or are they enhancing naturally occurring disequilibria, perhaps with even worse consequences? It is often argued that large-scale fluctuations in climate and sea-levels have occurred over and over again in the geological past, long before human activities could possibly have had any impact, and that human effects are very small compared to those that occur naturally. Should we conclude that human activity cannot significantly affect the environment, or are these naturally occurring fluctuations actually being dangerously enhanced by humans? This book examines these questions, first by providing evidence for equilibrium and non-equilibrium conditions in relatively undisturbed ecosystems, and second by examining human-induced effects.