THE DEVELOPMENT OF FLIGHT SURFACES ON THE AVIAN WING

The evolution of the feathering arrangements that comprise the modern avian wing can be tracked using both physical evidence from the known fossil record and interpreting the aerodynamic theory. Evidence from both the fossil record and from living birds suggests that all feathered wings reflect the same basic structural plan. Here we review scenarios for the evolutionary history of the lifting surfaces of the feathered wing, suggesting non-locomotory influences on their early development and building on Pennycuick's (2008) aerodynamic theories for the eventual development of avian flight.