Monday, April 14, 2014

Additional pterosaurs of the AMNH




You may be aware that there is currently a major new pterosaur exhibition opening at the American Museum of Natural History, entitled Pterosaurs: flight in the age of the dinosaurs. In addition to their existing collection going on show, a number of key specimens have been borrowed from China and Brazil in particular and there is new art, animations and life models of specimens.

Somewhat inevitably the Pterosaur.net crew are involved in at least some ways. I know that Mark has had an input on the reconstructions, and that Mike has talked to them about take off and flight. I've also heard that both terrestrial stalking an azhdarchids (from Mark and Darren) and floating posture (my recent work with Don Henderson) also get a look in as part of the displays, so even very new research is in there.

Here we are blessed with a few photos from the exhibit courtesy of reader Steve Cohen who is a volunteer there. Steve has generously taken photos before from the museum and passed them on, and here are a few more for the collection. Featured are Wukongopterus, Tapejara, Thalassodromeus and some other wonderful Brazilian and U.S. specimens, and I know material from the Solnhofen (including the dark wing, outside of Germany for the first time), pterosaurs tracks and even the first described egg are also on show. At least a couple of pterosaur researchers are planning a visit given the diversity of material and I hope to join the pilgrimage to see some of this stuff in the flesh. My thanks to Steve for taking the time to take these and send them on.



Thursday, March 20, 2014

A young intermediate pterosaur from Germany

A paper has just today been published describing this lovely specimen of what is rather obviously a) a juvenile pterosaur and b) something that is an intermediate between basal and derived pterosaurs. I've got some more photos and written up a brief bit here on it.

Thursday, March 13, 2014

Quad launching birds and relevance for pterosaurs

My recent G+ post has relevance to understanding pterosaurs. You can point your cursors here.

Bottom line is that quadrupedal launch is more common than it is typically given credit for. In fact, in terms of evolutionary origins, it has been more prevalent through time than bipedal launch.


Tuesday, February 4, 2014

Cataloging the Carnegie


 
Pterodactyloid specimen with the impression of a throat pouch preserved
The number of pterosaur specimens now known from the Solnhofen is very impressive, certainly in the hundreds, although with a good number sitting in private hands, plenty of information is kinda known about, without necessarily being in the literature. However, while it is easy to bemoan the inaccessibility of material that isn’t in museums, far too much that is available is not always looked at, and a great case in point is the collection of Solnhofen material in the Carnegie Museum in Pittsburgh. In the early 1900s, the Carnegie was able to acquire a large collection of fossils from a Belgian collector the Baron de Bayet, and this included considerable amounts of Solnhofen fossils including a dozen pterosaurs. This is arguably the best collection outside of Europe, or even outside or Germany, and includes material in 3D, with soft tissues, stomach contents and other rather nice details. However, in the following hundred years a total of just 10 papers even mention these specimens, and some of these are very much references in passing. The only even vaguely detailed mentions come from Peter Wellnhofer’s works from the 1970s, which are not easy to access these days, often available only with poor images, don’t illustrate all the specimens, and came in many cases prior to additional preparation or other modifications. In short, this is a major collection of pterosaurs which needs to be revisited.

While visiting Mike Habib in Pittsburgh, we were hunting for things to do and realised this was an area ripe for reappraisal and set to revising and updating the material. Joining forces with Carnegie curator Matt Lamanna, we have now published a long paper (appropriately enough in the Annals of Carnegie Museum) detailing the material and its history. Naturally we have not done detailed descriptions of the anatomy of the pterosaurs at hand – there are very good descriptions of  things like Rhamphorhynchus and adding to that would merely fill space without really conveying much useful information, so instead we focused on what is unique about each specimen (taphonomy, condition of the material, what is and isn’t present) and specific history of the material in places. For completeness, we even briefly covered the casts in the collection, and the skeletal models made by Wellnhofer when he was in the museum on a sabbatical many years ago. This still resulted in a manuscript of over 15 000 words (despite there being only a handful of references) and 15 figures (at least one of each specimen), while Mike rather heroically took dozens of measurements for each specimen and then repeated the exercise for accuracy. The paper is in black and white, but colour versions of the key figures are online here alongside the data.

Some of these specimens turned out to be much more interesting and potentially important than previously realised and we were also able to correct some previous problems and update the taxonomy. Recent revisions especially to the pterodactyloids has left a lot of collections lagging in their taxonomy, but there was also a large animal that was listed as Rhamphorhynchus, despite obviously being a pterodactyloid, and indeed actually doesn’t even bear much resemblance to any currently known Solnhofen pterosaur and is rather cryptic. Two specimens had been mistakenly thought to be a plate and counterplate and had been combined even though they were quite different. After much head scratching we realised the issue was that there was a plate and counterplate there, but thanks to effectively a typo, the wrong pair had been put together.

Rhamphorhynchus specimen prepared free of the matrix

Two specimens of Rhamphorhynchus have undergone pretty dramatic changes in recent years, having been fully prepared free of their matrix. In one case, this results in a very odd flat specimen (which is apparently now very fragile – I actually didn’t see either of these, they were away when I was at the Carnegie) but that is at least cleaned up, but the other is a near complete skull preserved in 3D. Many readers will remember the paper on pterosaur neuroanatomy led by Larry Witmer that compared the brain structures of Anhanguera and Rhamphorhynchus and this specimen was responsible for the data on the latter. Three dimensional material from the Solnhofen is not common, so a skull that is in 3D and prepared to the point that it can be seen in all views is a real treasure and while it has been scanned, we’ve included a series of large photos of it to help reveal the structure.

 
Rhamphorhynchus skull in near 3D (if lacking teeth) prepared free of the matrix

Several specimens show traces of soft tissues including the wings, throat sacs and tail vanes. None are especially well preserved, but nor ore these features that common either (in part perhaps because like the leg feathers of Archaeopteryx, they may have been destroyed in the past to ‘better’ prepare specimens), so any additional information is useful. Finally, one of them does appear to have some fish teeth associated with the stomach. We this is has been missed before by other people and so is a novel find, and that extends the set of Rhamphorhynchus specimens with fish gut contents and firms up the evidence for piscivory as a major part of the diet of these animals.

Hopefully therefore this paper will clarify a few issues with the collection, bring forwards some of the developments and details not previously seen or recognised and provides a basis for future research. Also of course it marks the beginning of the sad death of Matt Lamanna’s career as a researcher of dinosaurs and the slow and painful descent into working on pterosaurs and consorting with the kinds of people who actually quite like them. For this Mike and I can only apologise, or cackle wildly with unabandonned joy, depending on who is reading at the time.

Hone, D.W.E., Habib, M.B. & Lamanna, M.C. 2013. An annotated and illustrated catalogue of Solnhofen (Upper Jurassic, Germany) pterosaur specimens at Carnegie Museum of Natural History. Annals of Carnegie Museum, 82: 165-191.Link to PDF here.

Thursday, January 2, 2014

Pterosaur Aerodynamics at GWU

+Lorena Barba over at George Washington University had her students do some fun summaries of pterosaur aerodynamics at the end of the Fall Semester. She is a professor in engineering who runs a course on animal flight (she is also the CFD guru behind the latest analysis of gliding snakes with J. Socha). These topics followed from a discussion that Lorena and I had after some interesting (and amusing) trolling on my Google+ stream. We identified four topics for her students to look into more: pterosaur launch, pterosaur weight estimates, pterosaur wings and flight capabilities, and Wagner Effects. The students wrote blog posts, which can be found here:

http://lorenabarba.com/blog/student-guest-blog-post-pterosaur-quad-launch/

http://lorenabarba.com/blog/student-guest-blog-post-pterosaur-weight-estimation/

http://lorenabarba.com/blog/student-guest-blog-post-pterosaur-wings-and-flight-capabilities/

http://lorenabarba.com/blog/student-guest-blog-post-the-wagner-effect/

These students are all engineers, which adds a fun element because most were quite unfamiliar with pterosaur biology going into this project. There are some errors in the terminology and details of biology as a result, but it's quite good work, and brought some new things to light for me (especially the Wagner section). Enjoy!

Oh, and Happy New Year everyone...


Friday, December 27, 2013

So this is Christmas, and what have you done?...

...asked John Lennon and Yoko Ono, in November 1972, before most of the Pterosaur.net crew were even born.

This particular song is guaranteed to make me grind my teeth as I elbow my way through Aldi with a basket full of mince pies and a wet umbrella tucked under my arm. Yes, there's a bit of 'Bah Humbug' in me, I won't deny that, but that's not the whole reason. You will find other seasonal novelty songs on my iPod all year round, so why, I hear you ask, do I hate Happy Xmas (War is Over) with all my heart?

It's the opening lines really. So this is Christmas, and what have you done? Another year over, a new one just begun.

Groan. As if we need to be reminded that another year has shot by, and we haven't done half of the things that we wanted to. It's like being told off by your parents for dossing around in your pyjamas all day, instead of doing something useful.

But we haven't been dossing around in our pyjamas in the NHMUK pterosaur collection, contrary to any stories that you might have heard. It's been a busy year, as usual. I'd like to tell you how many collection visitors have been this year, but I don't have access to the stats right now, as I'm writing from the debris-strewn dining table at the Steel / Hume residence. Instead, let's go through the diary, and see what the NHMUK pterosaurs got up to in 2013.

The snout of the 'cookie-cutter' pterosaur Istiodactylus was CT scanned for a PhD project. At this stage I have no further information on what, if anything, this showed. The same project was to include SEM work on a single tooth. Several researchers are interested in this specimen, so I'm sure that this data will be useful to someone. Sadly, the student has decided not to continue with this project, making this the second time that a PhD project on Istiodactylus has stalled (if you'll pardon the pun). Perhaps it was cursed by the collector, Hooley, all those years ago.

Speaking of collectors, Heather Middleton kindly loaned her collection of Kimmeridge Clay pterosaur bones and teeth so that they could be photographed by those lovely chaps in the NHMUK photo studio. Some of Heather's specimens might feature in the pterosaur chapter of the forthcoming field guide to the Kimmeridge Clay (available in all good bookshops), which is edited by none other than Dangerous Dave Martill. He is also solely responsible for the pterosaur chapter, I believe. Heather's collection is far superior to the NHMUK material, and includes quite a few nice teeth.

The latest Isle of Wight pterosaur, Vectidraco, was described and named early this year.  For those that missed it, the specimen is a small pelvis that was found by a young girl about two years ago, and donated to NHMUK by her. News reached the ears of 'The One Show', a popular tea-time television programme, and to cut a long story short, I had about 24 hours notice to prepare the specimen and myself for live TV on April 11th. The museum's Head of Conservation made a mount and a box so that the specimen could travel safely to the studio without being handled. Daisy, the girl who found the specimen, was there too, with her whole family, but was a bit overwhelmed by the whole live TV thing, and went all shy. I was too busy trying to hold my tummy in, and worrying that I would forget the name Vectidraco.

I didn't make it to the Pterosaur Symposium in Rio de Janeiro this year, as it wasn't as heavily subsidised as the one in Beijing in 2010. But several people were kind enough to send me copies of the abstracts volume. Much appreciated. I have a couple of spares, if anyone missed out.

One of the Solnhofen pterosaurs travelled to Southampton University for a session in their big CT scanner. Unfortunately this didn't go as well as hoped. The images showed bedding in the matrix, but no contrast between it and the bones. Later in the year, I was back at Southampton again for the Wealden symposium, which was very well-attended. Dave Martill spoke about Istiodactylus. And the Great Wall of China.

One of the last big events of the year was 'Blast From the Past' at Dinosaur Isle. This is an open day at the museum in Sandown, Isle of Wight, with local collectors, palaeontologists, archaeologists and artists all showing their work and collections to the many visitors. For me it was a chance to see old friends and hear about some recent finds. I was expecting to meet up with Nick Chase to pick up a couple of Pholidosaurus skulls that he'd collected in Dorset in the late 1980s, but to my surprise he also donated a few other specimens from the Island. These include a few bits of small pterosaurs, and a theropod humerus. I also saw Mick Green for the first time in ages, and he brought along most of his pterosaur collection.

Finally, a painted cast of Dimorphodon has been exchanged with AMNH (for some casts of Mongolian dinosaur bones) and a cast of the snout of Istiodactylus will probably be exchanged with Dinosaur Isle for a cast of their new small croc. 

That's not all, of course. I won't bore you with all the croc-collection comings and goings, as presumably you came here to read about pterosaurs. So I will stop here, put on my pyjamas and watch my new DVD that I got for Christmas. It's called 'Flying Monsters' and it should be really good, because Sir David Attenborough is in it, and it has a blood-stained Dimorphodon on the front cover...


Wednesday, October 23, 2013

Yes, it's from the Solnhofen. Really.

I'll just leave this here. Enjoy.