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Pterosaur structure, good job JC
Dear John and dinolisters,
John Conway's excellent restoration of pterosaur anatomy is well
worth the look. His artwork, I think, places him as the heir apparent
to Doug Henderson.
John has envisioned the big traps and lats that so many artists miss.
But I notice John does not put adductors on the prepubis.
I would like John to comment on his placement of the pteroid in the
bowl of the pre-axial carpal, a placement that is not reflected in
the fossil record, as recently shown by Chris Bennett.
I also note that the radius and ulna are not in the neutral position,
but are suppinated. To move the radius to the neutral position
requires not more than about a quarter of an inch move distally
closer to the medial edge of the ulna and another look at the carpals
orientation. With wings extended that places metacarpals I-III in the
plane of the wing, as in other tetrapods and basal pterosaurs, not
pasted against the leading edge as it appears in John's drawing. I'm
also looking for and having a hard time seeing the big unguals in
fingers I-III. When the wing fingers are placed into the standard
tetrapod configuration and the radius is in the neutral position, the
fingers face each other during tree trunk climbing and they
hyperextend laterally during walking (with elbows oriented
posterolaterally), matching ichnites. How can this happen in this
configuration without some sort of strange humeral configuration?
I cannot agree with John's hypotheses on wing folding = extension
and wing deployment = flexion. I'll await a further explanation that
is more parsimonious than the torsioned wing metacarpal hypothesis.
Hopefully it will include a phylogenetic demonstration using
nonvolant sister taxa of how flexion was prevented and extension
became hyper-extension. I also don't understand why palmar flexors
can't flex (fold) the torsioned fourth digit.
I also liked John's earlier version of hind limb configuration during
flight in which the hind limbs were more laterally oriented forming
horizontal stabilizers. He mentioned examples of wing connection to
the thigh or ankle. I'd be very interested in seeing those delineated.
A tip of the hat to a great artist and visionary, Hope to see the
same specimen walking one of these days.