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Research by post-doctoral fellow Alexander Dececchi challenges long-held hypotheses about how flight first developed in birds. Furthermore, his findings raise the question of why certain species developed wings long before they could fly.

Dr. Dececchi, a William E. White Post-Doctoral Fellow in the Department of Geological Sciences and Geological Engineering, used measurements from fossil records and data from modern birds to test the evolutionary explanation for the origin of birds. Dr. Dececchi and his colleagues determined that none of the previously predicted methods would have allowed pre-avian dinosaurs to take flight.

“By disproving the idea that the predicted models led to the development of flight, our research is a step towards determining how flight developed and whether it can evolve once or developed multiple times in different evolutionary lines,” he says.

Dr. Dececchi and his colleagues examined 45 specimens, representing 24 different non-avian theropod species, as well as five bird species. After determining some critical variables from the fossils – such as body mass and wing size – they used measurements from living birds to estimate wing beat, flap angle and muscular output.

These values were used to build a model for different behaviours linked to the origins of flight such as vertical leaping and wing-assisted incline running (WAIR) – a method of evasion for many ground-based modern birds that has become a favoured pathway towards the origin of flapping flight in the paleontological literature. They also tested if any species met the requirements to take-off from the ground and fly under their own power.

Read the full story in the Queen's Gazette.