Book excerpt: Landscape Evolution: Landforms, Ecosystems and Soils asks us to think holistically, to look for the interactions between the Earth's component surface systems, to consider how universal laws and historical and geographical contingency work together, and to ponder the implications of nonlinear dynamics in landscapes, ecosystems, and soils. Development, evolution, landforms, topography, soils, ecosystems, and hydrological systems are inextricably intertwined. While empirical studies increasingly incorporate these interactions, theories and conceptual frameworks addressing landforms, soils, and ecosystems are pursued largely independently. This is partly due to different academic disciplines, traditions, and lexicons involved, and partly due to the disparate time scales sometimes encountered. Landscape Evolution explicitly synthesizes and integrates these theories and threads of inquiry, arguing that all are guided by a general principle of efficiency selection. A key theme is that evolutionary trends are probabilistic, emergent outcomes of efficiency selection rather than purported goal functions. This interdisciplinary reference will be useful for academic and research scientists across the Earth sciences. - Serves as a primary theoretical resource on landscape evolution, Earth surface system development, and environmental responses to climate and land use change - Incorporates key ideas on geomorphic, soil, hydrologic, and ecosystem evolution and responses in a single book - Includes case studies to provide real-world examples of evolving landscapes