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Pterosaur wings and refs
With regard to wing shape in pterosaurs. I have seen direct evidence of
brachiopatagium attachment to the hind limb, as far as the ankle, in Sordes,
Rhamphorhynchus, Pterodactylus and what is probably Tapejara. I have also seen
very good photographs of specimens of Eosipterus (the specimen described by Lü
2002) and Jeholopterus that also appear to show exactly the same thing. So, the
same relationship seems to be present in six different pterosaurs representing
at least four completely distinct major clades. Add to this Hazlehurst's (1991)
discovery of a good correlation between fore and hind limb length in
pterosaurs, the general similarity of appendicular morphology across a wide
range of taxa, including all those with direct evidence of brachiopatagium
attachment to the hind limbs, and one ends up with a clear, well integrated
picture of whats going on in pterosaurs vis a vis wings and legs. Note that
this 'Sordes' model is also completely consistent with, for example, qu!
adrupedal plantigrady - as shown y thousands of pterosaur tracks, and is
supported by a new study by Matt Wilkinson (Cambridge) showing how effective
and aerodynamically advantageous wing attachment to the hind limbs was for
pterosaur flight. Since no one has ever presented any evidence, direct or
indirect to show that the brachiopatagium was not attached to the hind limb, in
any pterosaur, it is most parsimonous to assume that the Sordes model, at least
with respect to the brachiopatagium, applies to all pterosaurs. Reconstructing,
the exact shape of the brachopatagium, as it was in life, is more problematic
in that its not clear how extensible it might have been originally. Certainly
what is evident in fossils should probably be taken as the minimum.
If you want to read the latest about snappy flappers try these:
A tale of a tail:
Dalla Vecchia, F. M. 2002. A caudal segment of a Late Triassic pterosaur
(Diapsoda, Pterosauria) from North-Eastern Italy. Atti de Museo Friulano di
Storia Naturale 23, 31-58.
Jeholopterus and its relationships:
Dalla Vecchia, F. M. 2002. Observations on the non-pterodactyloid pterosaur
Jeholopterus ningchengensis from the Early Cretaceous of Northestern China.
Natura Nascosta 24, 8-27.
Giant pterosaur tracks:
Hwang, Koo-Geun, Huh, M., Lockley, M.G., Unwin, D.M. and Wright, J.L. 2002. New
pterosaur tracks (Pteraichnidae) from the Late Cretaceous Uhangri Formation, SW
Korea. Geological Magazine, 139 (4), 421-435.
Cearadactylus: yes, its a gnathosaurine ctenochasmatid ctenochasmatoid.
Unwin, D. M. 2002 On the systematic relationships of Cearadactylus atrox, an
enigmatic Early Cretaceous pterosaur from the Santana Formation of Brazil.
Mitteilungen Museum für Naturkunde Berlin, Geowissenschaftlichen Reihe, 5,
Institut fur Palaontologie, MUSEUM FUR NATURKUNDE
Zentralinstitut der Humboldt-Universitat zu Berlin
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0049 30 2093 8577 (office)
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0049 30 2093 8868 (fax)