A recent study published in the Journal of Vertebrate Paleontology reveals that some species of pterosaurs flew by flapping their wings, while others soared like vultures. This study challenges the long-debated belief that the largest pterosaurs were incapable of flight. The research, conducted by experts from the University of Michigan, the Natural Resources Authority, and Yarmouk University in Jordan, as well as the Saudi Geological Survey, focused on two large-bodied azhdarchoid pterosaur species dating back to the late Cretaceous period.
The fossils of these pterosaurs were remarkably preserved in a nearshore environment on the margin of Afro-Arabia, allowing for detailed analysis of the internal structure of the wing bones through high-resolution CT scans. Lead author Dr. Kierstin Rosenbach notes that the three-dimensionally preserved bones are a rare find, as pterosaur bones are fragile and typically found flattened or not preserved at all. The CT scans revealed unique internal structures within the wing bones of these pterosaurs, shedding light on their flight capabilities.
One of the specimens analyzed, Arambourgiania philadelphiae, had a 10-meter wingspan with spiral ridges inside its hollow humerus, similar to vultures. The ridges are thought to aid in resisting torsional loadings associated with soaring flight. The other specimen, named Inabtanin alarabia, had a five-meter wingspan and a completely different internal bone structure. Its flight bones were crisscrossed by struts, similar to modern flapping birds, suggesting it flew by flapping its wings.
The coexistence of different flight styles in pterosaurs of varying sizes raises questions about the correlation between flight style and body size and which style was more common among pterosaurs. Dr. Rosenbach highlights the importance of this discovery in understanding how these ancient creatures lived and emphasizes the need for further research to explore the relationship between internal bone structure and flight capacity in pterosaurs.
The discovery of diverse flight styles among pterosaurs provides a unique opportunity to study the evolution of flight in vertebrates. By comparing the flight mechanisms of pterosaurs with those of birds and bats, researchers aim to gain insights into the evolution of flight behavior. The study’s authors, including Professor Jeff Wilson Mantilla and Dr. Iyad Zalmout, suggest that variations in flight styles may have been influenced by mechanical forces acting on the pterosaurs’ wings during flight.
Overall, this study enriches our understanding of pterosaur flight mechanics and opens up new research avenues for investigating the relationship between internal bone structure and flight behavior. By utilizing advanced imaging techniques and studying a diverse range of pterosaur specimens, researchers hope to gain a deeper insight into the evolution of powered flight in these fascinating prehistoric creatures.
