Biomechanics of the stance of the wing during flight in Anhanguera piscator and Tupuxuara leonardii (Pterosauria: Pterodactyloidea) and considerations on flight evolution in the group
Pterosaurs represent the first group of vertebrates to achieve active flight, featuring a fossil record stretching from the Late Triassic to the Upper Cretaceous. Despite being studied for over 200 years, there are still many controversial issues regarding this group, including concerning their flight, such as, for example, the configuration of the wing musculature, the posture assumed by the wings during flight, and the variation of this these between different lineages. In this sense, the present thesis proposes to (1) present a survey of the myological configuration in a wide spectrum of pterodactyloid pterosaurs, and (2) infer, through a biomechanical study, optimal wing posture during the static phase of flight from two pterodactyloid pterosaurs: Anhanguera piscator and Tupuxuara leonardii. This approach, unprecedented for the study in question, comprises the 3D virtual reconstruction of musculoskeletal models of these two species, and subsequent comparison between the optimal positions assumed by the models of each of these species. The results obtained from the manipulation of such models may, in addition to providing information about the differences in wing posture in flight of these species, contribute to the knowledge of the evolution of adaptations of pterosaurs to flight, of the types of niches occupied by this group during the Mesozoic, and a possible compartmentalization of niches between pterosaurs and Mesozoic birds, thus enabling a better understanding of how flight would have evolved in this group of flying reptiles.