Darwinopterus

The concept of evolution is based on a simple idea. If an organism can survive to pass on its genes to the next generation it is said to be fit. Fit organisms will survive best and develop into dominant or abundant species.

Charles Darwin was the scientist who published this idea in 1858 On the Origin of Species… He proposed that a small and useful change, developed in relation to the environmental conditions would lead to a change in form or behaviour that, if advantageous, would persist in the species. Such small changes would lead to evolutionary change over time. These small changes can be seen to happen is some modern day species over time.

In examining different species, Darwin observed in many cases, that the change of form was significant. He proposed the idea of modular evolution where changes happened very quickly and locally at one time, giving a change that, if advantageous, was seen as a leap forward in evolution. Over time, where the environmental conditions were stable, the form and behaviour of species would be stable and show little change. Only when a significant factor changes the conditions within a habitat would other random changes become more advantageous. This concept is difficult to observe in reality, but it does rationalize the changes seen in fossils.

A recent find from China, Darwinopterus modularis, demonstrates this concept quite well. This is an advanced pterosaur in many features, but it has retained the long tail of the early pterosaurs. This species helps to link the changes between the Rhamphorhynchoidea and the Pterodactyloidea.

This pterosaur has been placed in a group called the Monofenestrata, which includes Darwinopterus and also encompasses all of the Pterodactyloidea.

Darwin C R, 1859, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. London, John Murray.

Lu 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 online before print October 14, 2009, doi: 10.1098/rspb.2009.1603

Proceedings of the Royal Society B - October 2009

The Problem With Ornithocheirus

The Ornithocheiridae are a group of large pterosaur fossils from the Cretaceous. They represent several distinct species and most are known only from fragmentary remains of jaws or bone joints. In many cases it is not clear which bones belong to which jaws.
In the late 1800's, this group of pterosaurs was represented mainly by remains in the Sedgwick Museum, Cambridge and the British Museum of Natural History (Now the Natural History Museum, London). The classification was a dumping bin for any pterosaur material from the Cretaceous that were not easily placed in an existing structural hierarchy. Many of the specimens were attributed to the work of Richard Owen or Harry Seeley.

This problem arose from specimens collected from the Cambridge Greensand. The specimens were deposited within the Greensand from elsewhere, perhaps from moving sediments or as fossils eroded from other rocks and re-deposited. In many cases, the age and location of the original deposition is unknown.
It has long been accepted that the Ornithosaur fossils represent a wide range of species that may well be unrelated. With little evidence of accociations, the work to sort the fossils out has not been done. Some time ago, David Unwin made a brave attempt at sorting out the problem and was successful in pulling some specimens out of the Ornithcheirus group, but with limited evidence, the problem will not be resolved easily.
Above is a sketch of a lower jaw fragment of Ornithocheirus fittoni, showing the staggered tooth pattern which is unusual amongst pterosaurs
Ornithocheirus sedgwickii shows a very different tooth pattern on its lower jaw. It may be that these specimens have enough similarities to place them in the same family group. If more was known about the rest of the skeletal remains, then a clearer perception would lead to a better conclusion. There are many more Ornithocheirids. Should they remain associated until such a time as there is more available fossil evidence. I personally do not have a problem with the idea of a dumping bin for odd bits and peices of remains. Science is full of problems and grey areas, so some means of containing these problems within a classification system is not a bad thing. The process often works well when a new specimen is found. You can take a look in the dumping bin from time to time and see if anything starts to look familiar.

Bowerbank J. S., 1851, On the Pterodactyles of the Chalk Formation. Proc. zool. Soc. Lond.,
pp. 14–20 & Ann. Mag. nat. Hist.(2) 10, 372–378.

Fritsch A. & Bayer F., 1905 Neue Fische und Reptilien aus der böhmischen Kreideformation.
Prague, privately published. pp. 30–32 & pl. 8

Newton E. T., 1888, Notes on pterodactyls. Proc. Geol. Ass. Lond. 10, 406–424.

Owen R. & Bowerbank J. S., 1852, On a new species of pterodactyle (Pt. compressirostris,
Owen) from the Chalk. Ann. Mag. nat. Hist. 10, 372–391.

Owen R., 1859 On remains of new and gigantic species of Pterodactyle (Pter. fittoni and Pter. sedgwickii) from the Upper Greensand near Cambridge. Rep. Br. Ass. Advmnt Sci. 28 (1858), 98–103.

Seeley H. G., 1870, The Ornithosauria: an elementary study of the bones of pterodactyls,
Proceedings of the Cambridge Philosophical Society, 2(1870) p.186

Seeley H. G., 1876, On the organisation of the Ornithosauria. J. Linn. Soc. Lond. Zool. 13, 84–
107.

Unwin D. M., 1991, The morphology, systematics and evolutionary history of pterosaurs from the Cretaceous Cambridge Greensand of England, University of Reading (Unpublished), Ph.D. Thesis

Pterosaur skeletal sculptures

Bruce Mohn is a comparative anatomist, palaeontologist and Palaeo-Sculptor with a specialism in mesozoic vertebrates. He has recently completed skeletal models of pterodactylus and rhamphorhynchus for the Carnegie Museum and the quality of his work is outstanding.
The model components are crafted from observations of fossil material and investigative techniques to give a realistic life-like shape to each individual component of the skeleton. The assembly of the individual components uses wired supports to give an accurate representation of the complete skeletal structure of the animal. This technique allows the skeleton to be wired into any orientation or possition that was possible in life.
If you are able to visit the Carneige Museum, it is worth finding these skeletal models to view the 3D structure of these pterosaurs, which cannot be fully appreciated from diagrams.

Bruce is able to make bones or skeletons to order - this is fine bespoke craftsmanship of the best museum quality. His work can be seen at - Bruce Mohn sculptures at Dinoart

Bruce Mohn

Carnegie Museums

Belemnite Ink Reconstituted

Recently, Dr Phil Wilby and his team were working to extract well preserved remains from a site near Christian Malford in Wiltshire for the British Geological Survey. The outcome of this extensive dig was to recover specimens of belemnite ink which has been reconstituted and used to write with.

This work mirrors the work of Joseph Anning in 1828 when he drew an illustration of a fossil skull of Dimorphodon macronyx using reconstituted belemnite ink from the Jurassic specimens found near Lyme Regis in Dorset.

The new work is significant insofar as it will allow the ink from the Wiltshire specimens to be analysed in detail - something that has not been done before.

The specimens used were classified as Belemnotheutis antiquus and were younger than the Anning Specimens. The ink was reconstituted in the same manner by adding ammonia to liquefy the solid ink sac contents.

The article in The Times reports that - "The specimen is now in the British Geological Survey collection in Nottingham. Part of the ink sac has been sent to Yale University in New Haven, Connecticut, for more detailed chemical analysis. "

Mary Annings Pterodactyle

The Times - 19 August 2009 Article by Simon de Bruxelles

The Times - 22 August 2009 Dave Martill's Comment

Pterodactyls Alive in 1985

In 1985 the BBC broadcasted an edition of the popular series "Wildlife on One" entitled Pterodactyls Alive. The centrepiece for this program was a dynamic model of Dimorphodon macronyx, nicknamed Didi.
The model was made by Arril Johnson and was commissioned by Aardman Animations in July 1984 as an animation model for the series. The model was made after consulting the leading experts of the day. Kevin Padian, curator of the Museum of Paleontology at the University of California at Berkeley and Hugh Aldridge a bat flight researcher at Bristol University who both contributed ideas to the modelling process.
This interesting model now resides in a display at the Bristol City Museum and Art Gallery on Queens Road, Bristol, UK. It is worth a visit if you are in that part of the world.
These two photographs are mood shots taken by Arril Johnson before the model was handed over to Aardman for the filming of the program content. Both pictures are copyright of Arril Johnson and used with permission. The images are to be included in a rewrite of the Bristol City Museum page on the Pterosaur Database website in the near future.
It is work like this that stimulates discussion in pterosaur research. Kevin Padian proposed ideas about the morphology and locomotion of Dimorphodon which were a little slow to be accepted in some areas. Modelling like this helps to demonstrate the practicality of such suggestions and put these kinds of ideas into context.

Aldridge, H; 1986. Manoeuvrability and ecological segregation in the little brown (Myotis lucifugus) and Yuma (M. yumanensis) bats (Chiroptera: Vespertilionidae). Canadian Journal of Zoology 64:1878–1882.

Johnson A; 1986, Didi a model with a difference, The Geological Curator Vol 4 ,No 5 page 289-290, September 1985.

Padian K; 1983, Osteology and Functional Morphology of Dimorphodon macronyx (Buckland) (Pterosauria: Rhamphorhynchoidea) based on new material in the Yale Peabody Museum, Postilla (Peabody Museum of Natural History), No.189, 1-44.

Park Hall Country Park

In 1985, Steven Winkworth made the first large scale flying model of Pteranodon, which he flew over the Dorset Coast. The model was used in the BBC television program - Pterodactylus flies. This event was published in New Scientist and in the national newspapers of the time, but outside of the world of pterosaur enthusiasts it is not a well known event.
This weekend I walked at Park Hall Country Park in Staffordshire. Having popped into the visitor centre for an ice cream I was confronted by a painting of the Steven Winkworth flying model on the wall in front of me.
The painting was done by Christopher Guest some 5 years ago, when he worked for the Community Art Team of Stoke-on-Trent City Council, run by Paul Bailey. The wall painting is quite a faithful representation of the model, as can be seen from the photographs. What an unusual find!
This small exhibit room boasts quite a few pterosaurs, like these Quetzalcoatlus soaring in the skies, perhaps over Stoke - who knows.

Park Hall is a site of special scientific interest for its glacial deposits and bedded gravels, as well as having a wide range of different biological habitats in close proximity. Not a place where you would expect to find Pterosaurs.

Winkworth S., 1985, Pteranodon Flies Again, New Scientist, 3 Jan 1985: p32-33.

Winkworth S., 1985, Pteranodon, Flug und Modelltechnik, 359, p990-993. Verlag fur Technik und Handwerk, Baden-Baden.

http://www.steep-steep.blogspot.com/

Resolving Criorhynchus

In 1861, a new species of pterodactyl was published by Richard Owen. The specimen was the end of a snout with a couple of teeth and 5 tooth sockets. He called this specimen Pterodactylus simus. A few years later he assigned the specimen to a new genus Criorhynchus simus. Harry Govier Seeley also published the specimen as Criorhynchus simus and added other specimens of anterior jaw fragments to this genus.

Several upper jaw snouts were discovered from the Upper Greensand. This is a derived deposit which contains lots of fragmentary remains. The nature of this pterosaur was not well known and analysis of the remains were very speculative at the time.

With no associated remains Criorhynchus was just a series of similar snouts. For many years the consensus was that this was a short snouted large pterosaur with a solid jaw and a very powerful bite.

It was not until 1987 when Peter Wellnhofer described a specimen from Brazil which he called Tropeognathus mesembrinus. This was one of those inspirational discoveries which put the Criorhynchus specimens into context. These species were interpreted as skim feeders with an aqua dynamic snout tip crest.
With increasing fossil evidence, this specimen was later re-assigned to the genus Anhanguera by Kellner and Campos in 1989.

Many pterosaur finds tend to follow this pattern of discovery and rediscovery. This is how science works. There are draws full of unassigned pterosaur specimens in museums around the world waiting for that magic moment when someone makes a discovery or a link that helps to put them into their correct context. Finding such resolutions is a joy.

Owen, R. 1861 Monograph on the fossil Reptilia of the Cretaceous Formations. Supplement III. Pterosauria (Pterodactylus). The Palaeontographical Society, London. (volume for 1858; pp. 1–19 & pls 1–4)

Owen, R. 1874 A Monograph on the Fossil Reptilia of the Mesozoic Formations. 1. Pterosauria. The Palaeontographical Society, London. pp. 1–14 & pls 1–2.

Wellnhofer P; 1987, New Crested Pterosaurs from the Lower Cretaceous of Brasil, Mitteilungen der Bayerischen Statssammlung fur Paleontologie und historische Geologie, 27: 175-186 Munchen

Kellner, A. W. A. & Campos, D. de A. 1990, Preliminary description of an unusual pterosaur skull of the Lower Cretaceous from the Araripe Basin. Atas I. Simp. sobre a Bacia do Araripe e Bacias Interiores do Nordeste, pp. 401–405.