During 2019, many researchers started to put older papers on line. The deposits in data holding sites are becoming more easily available as more information is stored centrally.
Here is a list of some of the best sites for obtaining copies of scientific papers. A membership or enrolment is often required before papers can be downloaded. Basic facilities are occasionally free of charge:
https://onlinelibrary.wiley.com/ Wiley Online Library
https://journals.plos.org/ Plos Journals
https://journals.plos.org/plosone/ Plos One Online Journal
https://peerj.com/ Journal of Life and Environmental Sciences
https://www.geolsoc.org.uk/ The Geological Society
https://www.jstor.org/ Ithaka Journal Service
https://www.palass.org/publications/ The Palaeontological Association
https://www.bgs.ac.uk/ British Geological Survey
https://www.academia.edu/ Academia
Saturday, 4 January 2020
Wednesday, 19 December 2018
Pterosaur Feathers
For a long time it has been known that some pterosaurs have hair. This has been seen as pycnofibers in some fossils. It is only with the advent of better quality fossils and improved techniques that the nature of these hairs is being better understood. This is documented in the following paper:
Yang Z., Jiang B., McNamara M. E., Kearnes S. L., Pittman M., Kaye T. G., Orr P. J., Xu X. and Benton M. J., 2019, Pterosaur integumentary structures with complex feather-like branching, Nature Ecology & Evolution, 2018; 3 (1): 24
There appears to be 4 types of hair like fibres found in pterosaur specimens of Anurognathus, Sordes, Jeholopterus and Pterorhynchus. It is probable that these fibres are found in many more pterosaur Genus groups. They are similar to feathery structures seen on some dinosaurs.
Type 1 - Pycnofibers. These are seen in abundance on Sordes Pilosis and have been documented before by Bakhurina and Unwin. These are seen to be hollow stemmed hair like fibres which are now known to contain melanosomes which are chemically similar to red and black pigment melanosomes and would probably have given a brown colouration to the fibres.
Type 2 and 3 - Radially symmetrical branching fibres. These are found on the head, neck and limbs of the sampled pterosaurs and may be associated with airflow dynamics or thermal insulation.
Type 4 - Bilaterally branching wing fibres. These feather like fibres are found across the wing membranes and are similar to some dinosaur feather structures, suggesting a distant common ancestor. This wing membrane association could be involved with insulation or thermoregulation.
When I see structures like this, I look to the function of wing contour feathers in birds. It is likely that these feathered structures may also have been sensory, giving information about airflow over the flying surfaces to warn of stall limits and variable pressures on those surfaces.
This work is an important enhancement of current knowledge about pterosaur biology and shows more detail about these advanced flyers.
These structures are seen as compacted masses of hair like mats on suitably well preserved fossils. Extracting information about single hairs is quite an achievement.
Yang Z., Jiang B., McNamara M. E., Kearnes S. L., Pittman M., Kaye T. G., Orr P. J., Xu X. and Benton M. J., 2019, Pterosaur integumentary structures with complex feather-like branching, Nature Ecology & Evolution, 2018; 3 (1): 24
There appears to be 4 types of hair like fibres found in pterosaur specimens of Anurognathus, Sordes, Jeholopterus and Pterorhynchus. It is probable that these fibres are found in many more pterosaur Genus groups. They are similar to feathery structures seen on some dinosaurs.
Type 1 - Pycnofibers. These are seen in abundance on Sordes Pilosis and have been documented before by Bakhurina and Unwin. These are seen to be hollow stemmed hair like fibres which are now known to contain melanosomes which are chemically similar to red and black pigment melanosomes and would probably have given a brown colouration to the fibres.
Type 2 and 3 - Radially symmetrical branching fibres. These are found on the head, neck and limbs of the sampled pterosaurs and may be associated with airflow dynamics or thermal insulation.
Type 4 - Bilaterally branching wing fibres. These feather like fibres are found across the wing membranes and are similar to some dinosaur feather structures, suggesting a distant common ancestor. This wing membrane association could be involved with insulation or thermoregulation.
When I see structures like this, I look to the function of wing contour feathers in birds. It is likely that these feathered structures may also have been sensory, giving information about airflow over the flying surfaces to warn of stall limits and variable pressures on those surfaces.
This work is an important enhancement of current knowledge about pterosaur biology and shows more detail about these advanced flyers.
These structures are seen as compacted masses of hair like mats on suitably well preserved fossils. Extracting information about single hairs is quite an achievement.
Saturday, 3 February 2018
Pterosaur T-Shirt
Studio 252MYA has a range of T-shirts, some of which have pterosaur motifs. They are on sale over the Internet from the US, and can be mailed to most parts of the world.
They start at $22 US and there is postage and tax to add to the cost if you are outside of the US. These are the first pterosaur related T-shirts that I have been satisfied with and they come in a variety of colours and designs.
The T-shirt shown cost a total of $30.96 to be shipped to the UK. This was a total of £22.56 at the then current exchange rate and took 12 days to arrive on my doorstep.
(If in doubt, go one size larger than expected)
Thursday, 6 July 2017
Wukongopterus Lii
The "Dinosaurs of China" exhibition is now open at Wollaton Hall, Nottingham. This is an exceptional chance to see some of the most important fossil finds from China at first hand. The most interesting specimen for me was not the immense casts of the large sauropod and raptor dinosaurs, but the last fossil in the display - The pterosaur Wukongopterus lii.
This specimen is held in a glass case with the reflections of the hall showing on any photograph, but visually, the detail of this fine fossil can be seen.
The magic of direct photography brings the full detail of the specimen to view. Previously I have only seen drawings and press images of this fossil. To see the complete specimen is stunning.
This is a basal pterosaur from the Daohugou Beds of Liauning Province. This is the Holotype - IVPP V-15113. It is one of the earliest forms of its type from the Late Jurassic, showing similarities with other earlier forms like Darwinopterus.
For me, The exhibition was worth seeing for this one specimen.
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.
Another interesting fossil is that of Yi qu, a modest sized feathered dinosaur with a bird like skeleton and what appears to be a bat like wing. This unusual anatomical structure poses questions about its lifestyle.
Of course, the largest specimen is the Mamenchisaurus hochuanensis which is 23m long and mounted upright to enable it to fit into the main hall gallery. Wow!
This specimen is held in a glass case with the reflections of the hall showing on any photograph, but visually, the detail of this fine fossil can be seen.
The magic of direct photography brings the full detail of the specimen to view. Previously I have only seen drawings and press images of this fossil. To see the complete specimen is stunning.
This is a basal pterosaur from the Daohugou Beds of Liauning Province. This is the Holotype - IVPP V-15113. It is one of the earliest forms of its type from the Late Jurassic, showing similarities with other earlier forms like Darwinopterus.
For me, The exhibition was worth seeing for this one specimen.
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.
Another interesting fossil is that of Yi qu, a modest sized feathered dinosaur with a bird like skeleton and what appears to be a bat like wing. This unusual anatomical structure poses questions about its lifestyle.
Of course, the largest specimen is the Mamenchisaurus hochuanensis which is 23m long and mounted upright to enable it to fit into the main hall gallery. Wow!
Friday, 30 June 2017
The Lapworth Museum of Geology
I have not had any contact with the Lapworth Museum at Birmingham University Edgbaston Campus since the mid 1980's. This museum has seen a significant improvement in many respects since then and is well worth a visit. The University railway station is a short walk away and it can be accessed from Redditch, Birmingham New Street or Litchfield.
There is a striking life size model of the skeleton of Pteranodon ingens suspended from the main fossil gallery ceiling. This gives a good idea of the size of these large Late Cretaceous pterosaurs.
A cast of the Bonn fossil of Scaphognathus crassidens shows how the Late Jurassic rhamphorhynchoid pterosaurs had sturdy skeletons and well armed jaws.
By contrast, the lighter and more gracile Pterodactylus antiquus skeleton cast of one of the Munich specimens shows a different type of Late Jurassic pterosaur. Both of these casts are of exceptional quality, being professionally produced from the original fossils. Many commercial copies are not nearly so good.
The museum collections are arranged to give a good understanding about the distribution of fossil types across geological time, which is exactly what a university museum collection should do.
Of course, there are other aspects of the fossil collections here that are just as interesting and amazing as the pterosaur offerings. Next time I am in Birmingham I shall consider another visit to this fascinating place.
There is a striking life size model of the skeleton of Pteranodon ingens suspended from the main fossil gallery ceiling. This gives a good idea of the size of these large Late Cretaceous pterosaurs.
A cast of the Bonn fossil of Scaphognathus crassidens shows how the Late Jurassic rhamphorhynchoid pterosaurs had sturdy skeletons and well armed jaws.
By contrast, the lighter and more gracile Pterodactylus antiquus skeleton cast of one of the Munich specimens shows a different type of Late Jurassic pterosaur. Both of these casts are of exceptional quality, being professionally produced from the original fossils. Many commercial copies are not nearly so good.
The museum collections are arranged to give a good understanding about the distribution of fossil types across geological time, which is exactly what a university museum collection should do.
Of course, there are other aspects of the fossil collections here that are just as interesting and amazing as the pterosaur offerings. Next time I am in Birmingham I shall consider another visit to this fascinating place.
Tuesday, 9 May 2017
The Biddulph Grange Gardens Pterosaur
On a recent visit to Biddulph Grange Gardens I was looking at the progress in the geology gallery when I spotted a pterosaur skull on a cast of a lithographic limestone slab. This was a pterosaur fossil that I had not been aware of. After contacting the grange, I
was put in touch with Daniel Atherton, who is part of the restoration
project responsible for the refurbishment of the Geological Gallery. I was invited to inspect the original slab which was recorded as a fish fossil due to the presence of a number of fish remains visible.
Amongst the fish jaws was a skull resembling that of Pterodactylus antiquus.
The skull is very worn and has many damaged and broken bones. The upper mandible is obscured by the presence of a fish jaw. The posterior skull is also broken and part of the basal skull is displaced downwards.
On the edge of the slab is what appears to be a wing bone association. On original inspection I glossed over this part of the slab. On closer examination, this represents the dorsal spine and sacrum, with caudal vertebrae at one end and a thoraxic vertebra at the other. Two fish bones are seen to line up with this associated group of pterosaur bones to give the impression of a pterosaur wing.
The fossil is stored away from the public, but a cast of this slab can be seen in the Geology Gallery at Biddulph Grange Gardens, Staffordshire.
This fossil was collected in Victorian times, but there is no record of the source. It has only recently been found to contain pterosaur material. More information will follow as it becomes available.
Amongst the fish jaws was a skull resembling that of Pterodactylus antiquus.
The skull is very worn and has many damaged and broken bones. The upper mandible is obscured by the presence of a fish jaw. The posterior skull is also broken and part of the basal skull is displaced downwards.
On the edge of the slab is what appears to be a wing bone association. On original inspection I glossed over this part of the slab. On closer examination, this represents the dorsal spine and sacrum, with caudal vertebrae at one end and a thoraxic vertebra at the other. Two fish bones are seen to line up with this associated group of pterosaur bones to give the impression of a pterosaur wing.
The fossil is stored away from the public, but a cast of this slab can be seen in the Geology Gallery at Biddulph Grange Gardens, Staffordshire.
This fossil was collected in Victorian times, but there is no record of the source. It has only recently been found to contain pterosaur material. More information will follow as it becomes available.
Sunday, 2 April 2017
Dinosaur Plate
I recently found this plate at the Emma Bridgewater factory shop in Stoke-on-Trent, UK. It has been decorated using a sponge print method by hand, showing a sauropod dinosaur surrounded by 8 pterosaurs. On the back rim can be seen a circle of brown trilobites.
This appears to be a one off design as it has not appeared on the factory stock sheets. There is a decorating studio on the factory premises where children and adults can pay a small fee for the opportunity to decorate their own pottery. This may be an uncollected piece which has been sold in store. It may also be a demonstration plate used by staff at the studio.
Apart from the source and the label on the back, I have no other information on this pottery piece. Having done an Internet search, it is clear that there is a lot of dinosaur and pterosaur stuff out there. It is quite fun to see what is available.
This appears to be a one off design as it has not appeared on the factory stock sheets. There is a decorating studio on the factory premises where children and adults can pay a small fee for the opportunity to decorate their own pottery. This may be an uncollected piece which has been sold in store. It may also be a demonstration plate used by staff at the studio.
Apart from the source and the label on the back, I have no other information on this pottery piece. Having done an Internet search, it is clear that there is a lot of dinosaur and pterosaur stuff out there. It is quite fun to see what is available.
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