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On the necks of azhdarchid pterosaurs, Jaime wrote...
> Sibbick's painting is hypothetical, rather than based
> on fact. I guess storks and other long-necked birds
> were the basis of the restoration, but that's a guess.
The Sibbick restoration was done under the supervision of Dave
Martill, Dino Frey and Lorna Steel and follows work by Frey and
Martill on the cervical vertebrae of _Arambourgiania_ and
_Quetzalcoatlus_. This was published in _Neues Jarhbuch_.
Azhdarchid necks do not seem to have had a great deal of motion - the
flat-faced centra and way the zygapophyses interlock indicate this - but
extensive dorsoventral motion could have been posible at the axis-
skull articulation and the thoracic-cervical transition point. These bits
have yet to be well described for any azhdarchid, so this is speculative.
Perhaps Jim C could throw in a few comments here.
The idea in the Sibbick painting is (Frey and Martill's) that these
pterosaurs were slow marine gliders that used ground effect, oriented
the neck so it was ventral to the most downward excursion of the
wingtip, and caught fish by grabbing from the water surface. The neck
is held pretty straight, cranial crests wouldn't be a good idea because
wind blowing in from the side would place a lot of torque on the neck,
and a very mobile thoracic-cervical transition point is a necessity. To
break the water surface with the minimum of resistance the animal also
has to have very blade-like distal jaws: hence the beak shape in the
_Arambourgiania_ model. I have a big problem with this in that I think
contact with the water surface for a flying animal of this size would
disrupt the glide, even at slow speed. This is something we spend a lot
of time arguing about.
"All these memories will be lost in time, like tears in rain"
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