. . . 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.

I The Natural Order.- 1 Species Richness in Plant Communities.- 2 Hierarchies of Cause: Toward an Understanding of Rarity in Vascular Plant Species.- 3 Peasant Farming Systems, Agricultural Modernization, and the Conservation of Crop Genetic Resources in Latin America.- 4 The New Paradigm in Ecology: Implications for Conservation Biology Above the Species Level.- II Processes and Patterns of Change.- 5 Reptilian Extinctions: The Last Ten Thousand Years.- 6 Loss of Biodiversity in Aquatic Ecosystems: Evidence from Fish Faunas.- 7 Threats to Invertebrate Biodiversity: Implications for Conservation Strategies.- 8 Forest Fragmentation and the Conservation of Biological Diversity.- 9 Issues of Scale in Conservation Biology.- III Population Biology and Genetics.- 10 Stochastic Modeling of Extinction in Plant Populations.- 11 The Effects of Inbreeding on Isolated Populations: Are Minimum Viable Population Sizes Predictable?.- 12 Conservation of Asian Primates: Aspects of Genetics and Behavioral Ecology that Predict Vulnerability.- 13 Genetic and Demographic Considerations in the Sampling and Reintroduction of Rare Plants.- IV The Practice of Conservation, Preservation, and Management.- 14 Ecological Management of Sensitive Natural Areas.- 15 Park Protection and Public Roads.- 16 From Conservation Biology to Conservation Practice: Strategies for Protecting Plant Diversity.- 17 The Role of Ecological Restoration in Conservation Biology.- 18 Why Should We Conserve Species and Wildlands?.- Epilogue.