Originally published in 1958, Elton's classic ecology text sounded an early warning about an environmental catastrophe that has become all too familiar today - the invasion of nonnative species. Elton explains the devastating effects that invasive species can have on local ecosystems in clear, concise language and with numerous examples. The first book on invasion biology, and still the most cited, Elton's masterpiece provides an accessible, engaging introduction to one of the most important environmental crises of our time. Reprint edition.