Metabolic rate sets the pace of life in organisms, shaping rates of growth, reproduction, survival and resource use in individuals. However, comparatively little is known about how metabolism affects broader ecological scales, such as species interactions, community assembly and diversity. My research address these questions. How does fast-metabolizing, 'warm-blooded' endothermy change competitive and predatory interactions compared to slower, 'cold-blooded' ectothermy? How does thermoregulation drive patterns of biogeography? What is the ecological and evolutionary significance of metabolic power?