Pterosaur structure, good job JC

[David Peters <davidrpeters@earthlink.net>]

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.

David Peters
St. Louis