Sunday, 24 January 2010
Rhamphorhynchus Wings
In 1880, a fine fossil of Rhamphorhynchus was found in the Solenhofen Shales. The work was published in 1882 and clearly showed the wing membranes and tail fin. This specimen was originally named Rhamphorhynchus phyllurus (now Rh. muensteri) and it was sold to the Yale Peabody Museum in New Haven, USA. As with the Zittel specimen, casts were taken and distributed to National Museums.
Since the original finds of pterosaurs with wing membranes preserved, There have been many examples from the Lithographic Shales in Bavaria. The specimen above is in the Humboldt University Museum in Berlin.
Perhaps the best specimen of a Rhamphorhynchus with wing membrane preserved is the 'Dark Wing' specimen which is sometimes called the 'Tischlinger' specimen. This is a reflection of the work of Helmut Tischlinger who produced an amazing set of ultra-violet photographic images of this fossil to enable more detail of the wing to be observed.
These and other fossils enabled the wing structure to be studied in detail, from the fibres that run across the cord of the wing to the different layers of tissue within the wing membrane. As a result, there is a high level of understanding about the wing membrane structure of these and other pterosaurs.
von Zittel, K. A. 1882 Über Flugsaurier aus dem lithographischen Schiefer Bayerns. Paläontographica 29, 47–80 & pls 10–13.
Padian K & Rayner J M V; 1993, Structural fibres of the pterosaur wing: anatomy and aerodynamics. Naturwissenschaften 80: 361-364.
Martill D M and Unwin D M; 1989, Exceptionally well preserved pterosaur wing membrane from the Cretaceous of Brazil, Nature, 340:138-140
Tischlinger, H. and Frey, E. 2002. Ein Rhamphorhynchus (Pterosauria, Reptilia) mit ungewöhnlicher Flughauterhaltung aus dem Solnhofener Plattenkalk. Archaeopteryx, 20, 1-20.
Saturday, 2 January 2010
Highlights of 2009
There have been some remarkable finds published in 2009. Something of a stepping stone in the understanding of pterosaur evolution.
1. Changchengopterus pani was found in Upper Jurassic rocks in China. It is a basal, non-pterodactyloid pterosaur. Basal simply means a more primitive form of pterosaur with characteristics of much earlier species.
2. Darwinopterus modularis is a Middle Jurassic pterosaur with an interesting combination of Rhamphorhynchoid and Pterodactyloid features. A whole new branch of classification had to be devised to accommodate this fossil between the Rhamphorhynchoids and Pterodactyloids. This is a good example of what Darwin meant when he developed the idea of modular evolution. Different characteristics developing at different times within a family of animals.
3. Wukangopterus lii is another Upper Jurassic Rhamphorhynchoid from China. It has a long toothed skull and shows more primitive features than Rhamphorhynchus.
4. Another Pterosaur track way has also been published. Pteraichnus nipponensis is a distinct and new type of pterosaur track way from the Lower Cretaceous. It was originally discovered in 1990 at Kiladani Dinosaur Quarry in Japan and it has just been published. This paper makes the point that most Cretaceous pterosaurs are very large species, but this and other track ways were made by smaller pterosaur species. There must be many fossils out there still to find.
There are a number of other pterosaur finds which are being worked upon at present and some of them are remarkable fossils. Hopefully they will be published soon, so that they can enter the scientific discussions and shed new light on the development of this interesting group of ancient fossil animals.
Happy New Year.
- Lü, J. 2009. A new non-pterodactyloid pterosaur from Qinglong County, Hebei Province of China. Acta Geologica Sinica (English Edition), 83(2): 189-199.
- Lü J. Unwin D. M., Jin X., Liu Y. and Ji Q., 2009, Evidence for modular evolution in a long-tailed pterosaur with a pterodactyloid skull. Proceedings of the Royal Society B. Published on line 14 Oct 2009.
- Wang X., Kellner A. W. A., Jiang S. and Meng X., 2009, An unusual long-tailed pterosaur with elongated neck from western Liaoning of China. Anais da Academia Brasileira de Ciências 81 (4):793–812.
- Lee, Y.-N., Azuma, Y., Lee, H.-J., Shibata, M., and Lü, J., 2009., The first pterosaurtrackways from japan. Cretaceous Research