The Oxford Animal Biology Series is an innovative new series of supplementary undergraduate texts in comparative animal biology. Topics within each book are addressed using examples from throughout the animal kingdom, looking for parallels that transcend taxonomy. Further reading sections will guide the student into the literature at greater depth. The series will be international in scope, both in terms of the species used as examples and in references to scientific work. Energy for Animal Life, the first book in the series, is about how animals get energy, and how they use it, a central topic in our understanding of animal biology. Life depends on energy, and much of the activity of animals is devoted to getting the food which is their energy source. It encompasses the food chain, from solar radiation and photosynthesis to food sources for herbiviores and for carnivores, and compares the merits of different designs of digestive system, and of different strategies for finding and