[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: More on the Jeholopterus pycnofibre study

comments inserted.

----- Original Message ----- From: "David Peters" <davidrpeters@charter.net>
To: "dinosaur mailing list" <dinosaur@usc.edu>
Sent: Friday, August 28, 2009 5:53 AM
Subject: re: More on the Jeholopterus pycnofibre study

In bats the wing shape is dynamic and ever-changing, tightening and stretching between the various elements (several fingers and the hind limbs). In birds the wing shape is more constrained by the orientation of the stiff feathers of unyielding length and the bending of the elbow and wrist. The hindlimbs are not involved. Which of these two are pterosaurs more similar to?


Certainly the forelimb membrane has the flexibility to extend as a wing and contract to almost nothingness during folding, as in bats, but pterosaurs have only one wing finger and the akinofibres restrict the shape of the wing.

Actually, within the limits of their range of motion, they modulate the shape of the wing, rather than restricting it.