We are interested in the evolution of hominin diets for several reasons. One is the fundamental concern over our present-day eating habits and the consequences of our societal choices, such as obesity prevalent in some cultures and starvation in others. Another is that humans have learned tofeed themselves in extremely varied environments, and these adaptations, which are fundamentally different from those of our closest biological relatives, have to have had historical roots of varying depth. The third, and the reason why most paleoanthropologists are interested in this question, isthat a species' trophic level and feeding adaptations can have a strong effect on body size, locomotion, "life history strategies", geographic range, habitat choice, and social behavior. Diet is key to understanding the ecology and evolution of our distant ancestors and their kin, the early hominins. A study of the range of foods eaten by our progenitors underscores just how unhealthy many of our diets are today. This volume brings together authorities from disparate fields tooffer new insights into the diets of our ancestors. Paleontologists, archaeologists, primatologists, nutritionists and other researchers all contribute pieces to the puzzle. This volume has at its core four main sections: DT Reconstructed diets based on hominin fossils--tooth size, shape, structure, wear, and chemistry, mandibular biomechanics DT Archaeological evidence of subsistence--stone tools and modified bones DT Models of early hominin diets based on the diets of living primates--both human and non-human, paleoecology, and energetics DT Nutritional analyses and their implications for evolutionary medicine New techniques for gleaning information from fossil teeth, bones, and stone tools, new theories stemming from studies of paleoecology, and new models coming from analogy with modern humans and other primates all contribute to our understanding. When these approaches are brought together, they offeran impressive glimpse into the lives of our distant ancestors. The contributions in this volume explore the frontiers of our knowledge in each of these disciplines as they address the knowns, the unknowns, and the unknowables of the evolution of hominin diets.