Re: Pterosaur bicentenary subjective report part II

[Silvio Renesto <renesto@mailserver.unimi.it>]

At 10.00 10/09/01 EDT, MKIRKALDY@aol.com wrote:

>Dear Silvio,

>Please go on with your report for the dinosaur list.  We enjoy hearing
about these conferences and the information that is given.
>

Thanks for the positive feedback!

 before I go on with the report, I would remember that the abstracts are
published in a special issue of of the journal "STRATA: Actes du
laboratoire de Géologie Sédimentaire et Paléontologie de l'Université
Paul-Sabatier Toulouse".

If you want a copy  you should contact
Francis Duranthon:

francis.duranthon@mairie-toulouse.fr

And that some extensive papers will be published in a special issue of the
Journal of the Geological Society (UK)

Now the second part of my SUBJECTIVE report:

Niels Bonde and Per Christiansen from Copenhagen presented an exceptionally
well preserved and prepared Rhamphorhynchus from Solnhofenwhich after
preparation has been exposed to acetic acid transfer method  after being
enncased in artificial resin. It provided an amazing well preserved
skeleton  showing feature impossible to reveal by mechanical preparation
(authors words). Among these amazing features there is the discovery of a
camerate type of pneumatization  of the cervical vertebraem, large
pneumatophores extend into the hollow centra making the vertebrae paper-thin .
If pterosaurs are ornithodiran or instead outside the Archosauria  the
presence of air filled cavities will have substantially different
phylogenetical consequences about homologies of the diverticula in
pterosaurs and theropods etc.

David Unwin (Berlin) presented an interesting morphological analysis of the
hind limb of pterosaurs in comparison with bats and birds.
In his opinion the extraordinary diversity of posterior limb morphology in
birds (from flamingos to parrots etc.) is allowed by the complete
decoupling of the two locomotory systems (wings independent from hind
limbs=flight mechanism decoupled from walking mechanism) while this
obviously does not appear in bats.
Pterosaurs evidenced some different trends in "rhamphorhynchoids" and
pterodactyloids, however the authors envisaged a low diversity pattern
posibly implying that here was no or limited decoupling of the two
locomotory systems (i. e. wing membranes connected with  hind limbs at some
extent.).

Jim Cunningham presented a detailed engineer study of the "T" sectioned
phalanges of azdarchids as a strenghtening system to help unload of
excessive aerodynamic loads in these pterosaurs characterized by a
**relatively** shorter wing.

Peter Wellnhofer presented a New Eudimorphodon from Late Triassic Seefeld
locality  (Austria) and Fabio  Dalla Vecchia showed pictures  of  a new
pterosaur from the same site which has a crested skull (!!!) and
denticulated (not serrated) teeth (the description is in press in JVP)

Other communications concerned computer generated modelization of pterosaur
skull structure in connection with stress resistance and also pterosaur
locomotion (which IMHO are extremely interesting but need some further
refinement), inferences about palaeocology on the basis of tracks, and some
interesting reports about findings distribution of specimens and tracksites
from Asia, South America etc.

The fact I do not describe them in more detail does not mean they are
unworthy of (at least some of them ;-)), but that being fascinated by real
(fossil) bones and functional morphology, I get more deeply in this ones. 

All the best,

                                        Silvio Renesto
                                



 
-

"where did Taiji come from? It came from Wuji "   
                                        (Wang Zongyue)
Dr. Silvio Renesto
Dipartimento di Scienze della Terra
Università degli Studi di Milano
via Mangiagalli 34
I 20133 Milano
Italy

phone +39-0223698232
fax  +39-02-70638261
e-mail:    renesto@mailserver.unimi.it
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