Meeting Abstract
Moth wing and body morphology, which evolve to meet the functional demands of a species, will influence both aerodynamic capacity and agility. In the morphologically diverse moth superfamily Bombycoidea, the sister-groups Sphingidae (hawkmoths) and Saturniidae (silkmoths) are known for their highly maneuverable and erratic flight patterns, respectively. Aerodynamic theory suggests that both low wing aspect ratio (AR) and wing loading enhance maneuverability, while high AR wings enhance aerodynamic efficiency. Interspecific variation in morphology is also expected to influence the inherent stability and maneuverability of an animal. To test these hypotheses, we quantify forewing morphology and loading across Bombycoidea. Maximum likelihood ancestral state reconstruction of wing AR and loading reveal patterns of divergence and convergence across the tree. With few exceptions, hawkmoths exhibit wings of higher AR and loading relative to silkmoths. Based on each group’s respective ability to maneuver, these patterns of hawkmoth and silkmoth wing AR and loading contradict the expectation. The evolution of high AR wings in the hawkmoth clade might be related to the group’s ability to hover. Further, several more recent smaller transitions in wing shape and loading indicate pairs of species facing significantly different neuromechanical challenges. These results are integrated into a wider analysis of bombycoid flight stability as a function of wing morphology, body inertia, and physiology in order to explore the correlated evolution of neural and mechanical determinants of flight performance in these diverse agile organisms.
