Origin of avian flight Origin of avian flight Around 350 BCE, Aristotle and other philosophers of the time attempted to explain the aerodynamics of avian flight. Even after the discovery of the ancestral bird "Archaeopteryx" over 150 years ago, debates still persist regarding the evolution of flight. There are three leading hypotheses pertaining to avian flight: Pouncing Proavis model, Cursorial model, and Arboreal model. "Archaeopteryx", the oldest known ancestor of modern birds, could provide clues to the origin of avian flight. In March 2018, scientists reported that "Archaeopteryx" was likely capable of flight, but in a manner substantially different from that of modern birds.
Specimens of Archaeopteryx its aerodynamic function as a flight feather. As the feather bears little resemblance to the retrices of the other full "Archaeopteryx" skeletons, it is generally thought to be a wing feather: Griffiths and others have concluded it was a remex, while Carney in 2012 interpreted it to be a covert feather. The feather has a relatively low degree of asymmetry, which Speakman and Thompson in 1994 concluded to indicate it as a secondary remex. If this is the case, then it would have originated from an animal smaller than even the Eichstätt specimen, which is the smallest "Archaeopteryx" specimen known