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Re: Wing attachment for pterosaurs, legs or tail?



>I'm currently working on a painting of a flight of pterodons and have come
>across a yet another anatomical controversy.  Did the trailing edge of the wing
>membrane of these beasts attach to the legs only, the legs then the tail, or
>the tail only?

Pteranodons are traditionally depicted with the wing membrane sweeping
back and incorporating hind legs and tail, similar to a modern bat, which
would give it bat-like locomotion when not on the wing.  Recent research
on wing structure shows a sandwich arrangements of fiber and skin, rather
than just skin, suggesting the membrane was not a simple flap, but a com-
plex structure that had very different levels of "stretch" in different
directions, a net effect similar to that of feathers on a bird's wing.
That is, the membrane could, apparently, stretch laterally for the wing
to reach out to the side, but may have been less prone to bending upward
in the middle on the downstroke, which means less trailing-edge reinforce-
ment would be needed.  If this is the case, then a number of pterodactyl
fossils including pteranodon show that the fiber-reinforced membrane ended
at mid-hip, which would give the animal bird-like wings, bird-like flight,
and bird-like bipedal locomotion on the ground.  This is, however, a source
of considerable controversy, so expect at least a 2:1 disagreement in
followups from this point on :)

While I truly think the "new" dinosaurs seem more "real" and more "realistic"
to me, I must admit to a degree of sorrow at losing the slow-moving reptilian
behemoths of my distant youth.  I hope that there will always be room in
coursework and museums to remember what dinosaurs "used to be", rather than
what we now admit they probably were like.  It would be interesting to take
old illustrations of the splay-legged, reptilian brontosaurus quietly munching
soft river plants in shoulder-deep water and place it next to the confident
giant striding across the plains of the primeval feldt, the clumsy batlike
scrabbling, the headlong plunge off a cliff, and the slow soaring of the first
pteranodon reconstruction next to the modern image of the precise creature,
mincing daintily along an antediluvian shore and launching itself powerfully
into the air when danger threatened.  Remembering what we once took as the
truth and recognizing the implicit prejudice that lead us so far astray is
a worthy goal, but it must be admitted that those never-existed creatures
had a grandeur all their own.

Larry Smith
larrys@alpha.zk3.dec.com