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re: Flight of _Sharovipteryx
David Peters wrote:
> The key to this thread is long legs (longer tibia
> than femur) = cursor.
>>Refer to (and I guess you've already seen it, but it can't hurt to look
>>again): Dyke, G.J., Nudds, R.L. and Rayner, J.M.V. (2006). Flight of
>>_Sharovipteryx mirabilis_: the world's first delta-winged glider. J. Evol.
>>Biol. 19: 1040-1043.<<
>>>If the length of the femur is functionally constrained (especially if wing
>>>shape is governed by femoral protraction, as Dyke &c propose), then
>>>increased length of the wing could only be achieved by elongation of the
>>>lower hindlimb. Under this scenario, the intramembral proportions of
>>>_Sharovipteryx's_ hindlimb have nothing to do with bipedal/terrestrial
>>>locomotion, but are an adaptation to gliding.Cheers Tim<<
Point 1: DNandR never actually _found_ forelimb membranes or forelimbs(!) in
Sharovipteryx. Their paper was entirely hypothetical.
Point 2: The keyword "If" and "under this scenario" are not supported by
evidence. If you disagree, simply provide evidence. I'd love to see it.
Point 3: Pterosaurs also have uropatagia, they walk and run as evidenced by
tracks, and their tibia are typically longer than their femora, but that is a
pleisomorphic character going back to preflapping taxa, like sister taxon,