Re: T&F talks, SVP, Pteraichnus

["James R. Cunningham" <jrccea@bellsouth.net>]

david peters wrote:

> Jaime Headden wrote:
>
> Tow claw scratch-marks aside, very fascination implications, especially since
> one of the authors of the abstract at the time I think still considers
> pterosaurs to be bipedal.

'One of the authors' appears to think now that the 'landing' pterosaur was 
functionally quadrupedal, but that it was capable of taking some bipedal steps 
when the occasion arose.  I would agree with that assessment.

> In fact, as Chris has published with regard to Nyctosaurus, bipedal or 
> quadrupedal was essentially the same configuration. I echo that comment, but 
> extend the same configuration to all pterosaurs.

Quetz has shelves built into the glenoid, the humerus, and the elbow that allow 
'bone matching bone' supporting contact with the elbow raised well above the 
shoulders so that the spine can be horizontal when the animal is in quadrupedal 
position on those occasions when it chooses to do so.  I would presume that the 
spine is more often inclined as in the conventional posture.

Jim