Wednesday, 14 September 2016

Jurassic Kites

This summer I found a kite design by a company called Jurassic Kites.  Having sent for one, just for fun, I had go.  The design was developed by Sibyl King and it is manufactured by Peterkin UK Ltd.

 The kite comes neatly folded in a thin sleeve and is ready harnessed, just needing two pins fixing to brace the wings and a line (supplied)  attaching to the harness loop.
 Then its up to the top of a windy Knoll - in this case the hills under Thorpe Cloud at Ilam, Derbyshire, UK - Then up it goes.
 The first attempt was in low gusty winds and the kite was easily stalled.  It took some skill to keep it airborne.  With a smaller relative surface area than a conventional kite, this one needs a constant 5+ knot wind ( at least 6 miles per hour) to keep it aloft.
 This was no problem as the wind speed increased.  At a distance, this is a quite convincing kite.  The streamers are needed to stabilise the kite direction.  Without them it will loop wildly.  I am tempted to try it with shorter wing streamers, but that will wait until I have some lighter ribbons of clear plastic.
 With a little more wind, the kite becomes much more stable.
Bringing it down is easy if you peg the cord to the ground and walk along shortening the cord until the kite is near ground level.  Much quicker to crash the kite, but I want to fly this one again.
It is years since I seriously flew a kite - What fun.

Saturday, 27 August 2016

Gordon Cullen


In 1958, a tile wall mural was commissions for the lower precinct in Coventry.  It represented much of the history of the city.  The work was undertaken by Gordon Cullen and installed during the redevelopment in 1958.
As part of the mural, there is a wall showing prehistoric creatures.  On is a representation of a pterosaur.

This could be of Dimorphodon macronys, though the characteristics are very generalised.  It is good to see such a ceramic representation from 1958.

Tuesday, 28 June 2016

Pterosaurs at Liverpool

 Having recently visited the Liverpool World Museum to see the cast of Quetzalcoatlus northropi suspended in the Foyer, I saw a number of specimens on display in the galleries.  The specimen in the foyer is big and imposing.
 In the education centre was a cast of a Tropiognathus skull.  This was a substantial sized pterosaur.
 A lone Rhamphocephalus bucklandi tooth from the stonesfield slate at Naunton, Gloucestershire was also on display.  This is a small, but complete tooth.
 Three plaster casts of small Solnhofen pterosaurs from the Lithographic Limestone of Bavaria are displayed along with a wing phalange of Pteranodon, from Kansas in the same display as the Rhamphocephalus tooth.
There is also a phalange from the lithographic limestone of Bavaria that is attributed to Pterodactylus.  Both ends are damages, but this seems a good association to me.

There is also a small, but somewhat outdated model of a pterodactylus, of which I do not have a photograph.  The World Museum at Liverpool is an excellent visit if you have not been before.

Thursday, 15 October 2015

Humerus crests

The large deltoid process in pterosaur humeri show a great degree of variation between species and families.  Early Rhamphorhynchoid species tend to have deep, long and flat deltoid processes whilst later species show a narrowing and extending of this process.  Later pterodactyloid species tend towards a curved deltoid process on the Humerus.
This shows an example of some of the types.  Two later pterodactyloid species on the left and three earlier Rhamphorhynchoid species on the right.
These examples of early Rhamphorhynchoid humeri show the simple joint structures and the flat profile of the deltoid crest
By contrast, the humeri of larger pterodactyloid species show a different structure.  The joint surfaces are more complex and the deltoid crest is far from flat, showing a curved shape with a pronounced articular surface.
The curved shape of the deltoid crest can be seen in these images.
Pterosaurs were a very diverse order of animals, showing a vast variation of forms across millions of years of time.  As they became more specialised, the skeletal structures showed more complexity.  Many of the structural bones of the skeleton demonstrate variation in this way, less so in the wing phalanges.

Monday, 20 April 2015

Web server issues

The Pterosaur Database has experienced a server file loss on the morning of the 19th April 2015.  The cause was an internal problem. About half of the files have been restored and the site is working in part.  It is hoped that all function will be restored in the next two days.  Alas, there is no backup server for this "free to use" site.

2 days on:  The server content has been restored to last months state, with recent files being updated manually.  I hope I have restored all of the files that were absent, but there may be issues with some missed updates.  It is unlikely that this technical failure will be repeated. I took the option of a server side recovery as a total reload would have used up vast amounts of upload time  (15 minutes as opposed to 26 hours).  All seems well so far.

Tuesday, 7 April 2015

The bare bones

Anna Chekovsky has requested permission to translate some of the pages of this blog into French at http://www.teilestore.de/edu/ .  Initially there was an issue with copyright of images and permissions had to be sought.  In the process, this put me back in touch with Bruce Mohn, the well renowned skeletal reproduction sculptor.  His portfolio of work has expanded considerably since 2009 and I am very impressed by the superb quality of his models.
 His model of Pterodactylus Antiquus represents a skeleton based on several good specimens of this, the first known pterosaur species, giving it a very modern stance based on current research.
Equally, the model of Rhamphorhynchus muensteri is a classic reproduction sculpture of the famous Solnhofen Slate pterosaur skeleton.
I am now starting to develop pages based on people who are able to offer such items as would grace any museum of repute.  The reproduction pages are hopefully going to develop as time progresses.

http://www.pterosaur.org.uk/PDB2012/M/reproductions/ReproIndex.htm





Friday, 13 February 2015

Wisbech and Fenland Specimens

Wisbech and Fenland Museum was first opened in 1847 in its present form.  It is amongst the oldest purpose built museums in the UK and the character of its galleries are typically Victorian in essence.  However, the museum functions as a sophisticated modern organisation in all other respects.  This is a museum not to be missed if you are within travelling distance.
Behind the scenes there are a few fragmentary pterosaur bones within the collections.  They are not remarkable, but such fragments should not be forgotten as they may help shed light on other specimens, as yet unknown.
This pelvic bone fragment has only its original label for information.  It is most likely from a large Rhamphorhynchoid pterosaur from the Middle Jurassic age.
Here is a bone that has its extremities missing.  Such specimens are very difficult to identify beyond the anatomical position of the bone on a skeleton.
Here is a more complete and much more finely preserved bone which shows some similarity with Dsungeripterid pterosaur bones.  More work is needed here.

J317-Pterodactylus longicollum  Wing metacarpal (right)
J319a-Rhamphorhynchoid sp  Wing metacarpal (proximal)  
       about 50% of length of bone, Stonesfield Slate 
J319b-Rhamphorhynchoid sp  Wing metacarpal 
       (shaft fragment), Stonesfield Slate
J320-Rhamphorhynchus sp  Humerus (left, dorsal aspect),
      
Stonesfield Slate
J321a-Rhamphorhynchoid sp  Tooth,
Stonesfield Slate
J321b-Rhamphorhynchoid sp 
Tooth, Stonesfield Slate
J321c-Rhamphorhynchoid sp  Scapula
, Stonesfield Slate

      -Indeterminate  Pubis (of a large pterodactyl), Stonesfield Slate
      -Indeterminate  Wing metacarpal (fragment)
, Stonesfield Slate


The Stonesfield Slate is a deferred deposit which contains a significant number of fragmentary fossils that are Middle Jurassic in age. Pterosaurs from this age are very rare and not well studied compared to those of other geological ages.