This second edition provides an updated and expanded synthesis of feedbacks and interactions between insects and their environment. A number of recent studies have advanced understanding of feedbacks or provided useful examples of principles. Molecular methods have provided new tools for addressing dispersal and interactions among organisms and have clarified mechanisms of feedback between insect effects on, and responses to, environmental changes. Recent studies of factors controlling energy and nutrient fluxes have advanced understanding and prediction of interactions among organisms and abiotic nutrient pools.