Caterpillars are excellent model systems for the investigation of insect-plant interactions, predator-prey interactions, and insect physiology. Despite this, however, there is at present only a limited understanding of the constraints on foraging patterns of caterpillars. A major problem is the difficulty of designing and analyzing experiments which account for multiple constraints. Caterpillars: Ecological and Evolutionary Constraints on Foraging reviews the present state of research into caterpillar biology while arguing for a multiple factor approach in studying insect herbivores. Written by leading authorities in entomology and ecology, it provides an explicit framework for carrying out such investigations. The book details the constraints of the foraging patterns of caterpillars, including phylogenetic constraints, the physical environment, nutritional supply and demand, predators, and plant chemical defenses. It also analyzes caterpillar adaptations, such as sociality, mutualism, aposematism, and cryptic morphology, and covers population dynamics and the influence of environmental factors upon tropical, temperate, and arctic caterpillars. The book concludes with a discussion of the implications of this material for pest management, forest systems, and agroecosystems.