Our group works on the biomechanics, energetics, and evolution of animal flight. Flight performance is investigated in the laboratory using high-speed three-dimensional videography, metabolic measurements, particle-image velocimetry, and physically-variable gas mixtures. Two current projects are to describe hummingbird kinematic and metabolic responses to various forms of aerodynamic challenge, and to evaluate the functional correlates of wing reduction among a diversity of stick insect species. Laboratory studies of flight biomechanics are complemented by fieldwork around the planet, including the ecophysiology of butterfly migrations in Panama, gliding in Southeast Asian flying lizards, hummingbird flight metabolism across elevational gradients in Peru, high-altitude adaptations in Sichuan bumblebees, and controlled aerial behavior in wingless hexapods of the Neotropical forest canopy.