Well over a century after Darwin gave biology its unifying theory of evolution, the earth sciences experienced a similar revolution and the theory of plate tectonics took hold. Plate tectonics posed the idea that the earth's crust is divided into a number of large, thin plates always in motion relative to one another. In The Behavior of the Earth, world-renowned earth scientist Claude Allègre sets forth the exciting events in this contemporary revolution from its first stirrings in the nineteenth-century and Alfred Wegener's original model of continental drift (1912) through the development of its full potential in modern plate-tectonic theory. Few scientific theories have been so all-encompassing, and none has surpassed plate tectonics in explaining such a wide variety of geological phenomena, from the origins of mountain building to the formation of the ocean floor. As it integrated our knowledge of the earth's surface with the investigation of its interior, plate tectonics fused two previously autonomous strains of scientific inquiry. Continental mobility changed for all time our view of the earth from a static globe to an evolving, living planet, and allowed us to see that changes in the earth's surface are but exterior manifestations of a dynamic interplay of forces within the crust and the mantle.Allègre casts his lucid exposition of this scientific theory within the historical context of its struggle for acceptance. As he introduces us to the huge cast of personalities and researchers who contributed to the theory, he illuminates the complex role that the scientific community plays in the proliferation and acceptance of new ideas. Allègre is as insightful in discussing the human motivation for scientific endeavor as he is skillful in presenting the science that results from this effort. Richly illustrated and including a glossary, this book offers the reader rare access both to the central theory of plate tectonics and to the constellation of problems and possibilities that preoccupy earth scientists today.