Achievement

Aerodynamic studies using physical models of fossil organisms can provide quantitative information about how performance of defined activities, such as gliding, depends on specific morphological features. Such analyses allow one to rule out hypotheses about the function of extinct organisms that are not physically plausible and to determine if and how specific morphological features and postures affect performance. IGERT Trainee Dennis Evangelista, a mechanical engineer, and IGERT Co-PI Mimi Koehl provided a practical guide for the design of dynamically scaled physical models to study the gliding of extinct theropod dinosaurs that had flight feathers on its hind limbs as well as on its forelimbs. Their measurements of maximum lift-to-drag ratios of 2.5–3.1 for physical models suggest that its gliding performance was similar to that of flying squirrels and that the various leg postures that might have been used make little difference to that aspect of aerodynamic performance.