>Was there a gap in _Archaeopteryx's wing between the elbow and the body wall? < Graham Taylor published (1998?) a "pouncing protoavis" hypothesis of the evolution of flapping flight within the cursorial theropods based in large part on the belief that flight feathers (tertials) were absent between the elbow and the torso of Archaeopteryx. If the absence of elongated tertials in Archaeopteryx and others (such as Caudipteryx) is real and not simply an artifact of preservation, it raises fascinating issues with respect to the aerodynamic function of the prevolant arm/wing. This would suggest that the earliest aerodynamic surfaces formed by feathers on the arms of theropods were located distally and therefore much more likely to respond to selection for thrusting and braking than for lift. PTN
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