This book examines the concept of naturalness in ecosystems, discusses its values and considers choices about the level of naturalness in conservation efforts. The author argues that all ecosystems have been modified and the idea of places 'untouched by humans' is a myth. But there are large differences in the degree of modification and levels of naturalness which can be identified. Changes are not always irreversible; some apparent wilderness areas are sites of former civilizations. There is no longer any simple distinction possible between 'natural' and 'cultural' systems. In the future,...