|©Elise B (Elisetrations)|
30 June 2017
29 June 2017
Sometimes dinosaurs with very little material seem to be much more hyped than they deserve, but when the animal is as important to the evolutionary history of its line as Chaoyangsaurus is it is not much of a stretch of the imagination that the dinosaur deserves to be popularized in both the media and the professional paleontological community. The importance of the low-yield of material attributed to Chaoyangsaurus is not only in showing that our world hosted many different sizes of dinosaurs, but also in what is arguably the more relevant capacity of showing another link in the family history of ceratopsian dinosaurs and effectively enhancing our knowledge of their similarities and differences with their nearest cousins. This includes dinosaurs like Pachycephalosaurus. Though Chaoyangsaurus is a very distant relative, it certainly helps us fill in gaps in our knowledge. To that end, we have seen many attempts to understand the familial ties and to describe Chaoyangsaurus throughout this week that are impressive and have reached well into the professional, amateur, and general public arenas. There have not been cartoons or feature length movies, these arguably help the most to interest the general public, but there have been news stories and books like New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium. This book is a very technical tome of scientific presentations, but as a member of the general public, then an amateur, and now an in training member of the professional field, I can say that books like this generate a lot of interest in certain people around the world. Never underestimate someone that is keenly aware of what they want to learn and their ability to learn it in formal and informal settings; dinosaurs like Chaoyangsaurus that are less visible to the public than Tyrannosaurus but still are well known names with children (and it is, strangely and almost frighteningly) prove this mindset.
28 June 2017
|©Jamie A Headden |
Creative Commons Attribution 3.0 Unported
27 June 2017
Chaoyangsaurus was initially described in 1999 by Zhao, Cheng, and Xu in the Journal of Vertebrate Paleontology as an early ceratopsian from Liaoning, China. Their description included detailed maps of the region from where the fossils were recovered as well as detailed photographs of the type materials. Many of the remaining papers that reference the animal are more about the origins of ceratopsians and characteristics of the family that started showing up in animals like Chaoyangsaurus. These studies that mention the dinosaur include Xijin, et al.'s Houcheng Formation ceratopsian as well as Xu, et al.'s description of early ceratopsians and discussion about Liaoceratops. These discussions of the evolution of ceratopsians occur frequently in research and often discuss animals like Chaoyangsaurus, though not always of course, because the evolutionary history of ceratopsians is complicated and loaded with taxa.
25 June 2017
Chaoyangsaurus is one of the smaller dinosaurs we have discussed here and it has smaller facts and yet the same amount of fact pages as many of its larger ancestors, descendants, and contemporaries. These pages vary considerably but the information is generally similar or at least presented in ways that are appropriate for their target audiences. The most simplistic of these pages, as it always is, because the Natural History Museum of London wants to convey information as quickly and as easily as possible. Their page on Chaoyangsaurus is supposed to have a nice simplified line drawing of the dinosaur, but it is not loading for me today. Hopefully this simplified version of the dinosaur will load for other people. Prehistoric Wildlife, meanwhile, does not have any illustrations, but does augment the listed information with a very short written description of the animal. The Dinosaur Database takes both approaches and makes a single page with short written descriptions (shorter than Prehistoric Wildlife) and two different interpretations of Chaoyangsaurus. The two interpretations show the dinosaur as a typical, old school, taut skin reptile and the second version is actually the image shared yesterday. Despite this shorter interpretation of the facts, the pages all together paint a fairly complete picture of the dinosaur.
24 June 2017
Ceratopsians are interesting in their own right and some might even say that they look rather interesting. Prior to the evolutionary shift that leads to ceratopsians proper, a small ornithischian ancestor with a skull that shows some characteristics of basal ceratopsians without fitting into that family due to other, more differential, characters, was running about in the undergrowth and under the feet of giants. Chaoyangsaurus youngi Zhao, Cheng, and Xu, 1999 was named for the Chaoyang area and specifically after the Chinese paleontologist C. C. Young (Yang Zhongjian). Measuring in at approximately 1.1m (a little over 3ft), Chaoyangsaurus inhabited the Late Jurassic of China and is often depicted as a bipedal herbivore with (hypothetical) quills along the tail and caudal portion of the back. The speculative nature of this illustration is one of the first things that the artist acknowledges about the work but it also poses some interesting questions for us this week.
23 June 2017
As usual this week, this entry is a little shorter than our typical entries for any given subject. As interesting as illustrations about Triassic subjects can be, especially considering the majority of these animals that are illustrated are early dinosaurs. Dinosaurs that do not look much like what people expect dinosaurs to be are intriguing and sometimes confusing to many people; this is a conversation I have had many times over with random people. One of the more interesting illustrations that does exist of Efraasia is slightly older and depicts Efraasia walking almost quadrupedally, but with its hindlimbs in a position that suggests bipedal locomotion. This illustration, like all the other illustrations of Efraasia simply depicts the animal as is by itself and without any kind of background. This version of the sauropodomorph is simple, but does have odd fingers, and is somewhat salamander like in its general appearance.
22 June 2017
Efraasia was originally considered to be a small animal, based on fragmentary remains that could not be assembled extremely well, but it was later realized that the animal was much larger than believed. The estimated larger size is approximately 6.5m (21 ft). The dinosaur was still small for its size, but by small we mean gracile and lightly built rather than short or thin. The gracile hands and feet of the animal could be used to imply facultative quadrupedalism, though this is also implied by the fact that may other very early sauropodomorphs were known to be capable of moving bipedally and quadrupedally equally well. Poor pronation of the forearm, as some have hypothesized, may have limited Efraasia as an entirely bipedal dinosaur. Its gracile hands and digits were probably quite capable of grasping food items (and predatory animals and intraspecific competitors) which could then enable it to better survive its environment by adapting its diet (and defending itself more capably).
20 June 2017
We mentioned a number of articles, descriptions, and re-descriptions of Efraasia and thankfully there are a lot of examples of this writing hosted online in many different places. Only one of these writings is entirely about Efraasia and that is the Galton 1973 article that was previously described here. The paper (hosted on Springer's site), as many may remember, re-described a number of specimens collected by Eberhard Fraas and reassigned these specimens to a new genus named after a contraction of the collector's name; Eberhard Fraas was turned into the name Efraasia minor in this dinosaur.
19 June 2017
Unfortunately Efraasia never made it, yet at least, into any documentaries, cartoons, or movies. There really are not too many movies that use Triassic animals though, so the fact that it has not been in any movies is a little less surprising than the idea that it has not been in any documentaries. Cartoon dinosaurs are typically the more famous of the dinosaurs, so its exclusion from cartoons is equally anti-climactic. The only other video online, actually, is from a young man reading about and discussing Efraasia from Stephen Brusatte's published dinosaur field guide. Barring any other videos, which I would gladly post, here is the single video that is out there:
18 June 2017
17 June 2017
Efraasia minor (von Huene, 1907–1908) was a gracile middle-sized sauropodomorph of the Late Triassic of Germany. The name was not actually coined by von Huene, despite the fact that he originally described the fossil remains. The name von Huene gave the remains was Teratosaurus minor; this genus is a group of rauisuchians, which Efraasia was deemed to not be a member of. The name we use was coined by Peter Galton in 1973 when he reassigned a number of specimens to the new genus named after the collector of the specimens, Eberhard Fraas. Estimated at approximately 6 to 7m (20 to 23ft), Efraasia is a respectable size for its time and place, but, as we can see, it appears to have been a rather generic looking early dinosaur; however, it is a generic dinosaur that stands out for a number of reasons that we will discuss this week.
16 June 2017
Vladimir Trush and Vitaly Klatt. Trush appears to have sculpted a number of Tarchia inspired statues.
14 June 2017
The material of Tarchia is terribly incomplete to the point that size estimates of the animal are based on completely different animals, have been estimated from the smallest known remains at times, and have been independently made but not verified across a number of sources. This has made the dinosaur difficult to model in a popular context without arbitrarily picking one or another size estimate as the size of the model that will be illustrated, animated, or sculpted. It is partially this reason that there was no animated Tarchia until Dinosaurs Alive! was produced and other ankylosaurs of Mongolia were used in previous videos and films depicting that area of the world and its dinosaurs. Looking at these various estimates of size, however, Tarchia may appear to either have been the longest of Mongolian ankylosaurs with an estimated length of 8m (26ft) or a modest 4.5m (14.8ft). The upper estimate of 8m places Tarchia in the same size category as Ankylosaurus whereas the 4.5m estimate is within the range of Nodosaurus sized ankylosaurs. Basically this means that Tarchia was either a typically sized, though longer than any other Mongolian, ankylosaur or it was a smaller member of the ankylosaur family. This is important to our discussions on popular culture because the Tarchia model used in Dinosaurs Alive! appears to be of a similar size to the Tarbosaurus it is shown fighting. Tarbosaurus measures in with a range from 10m to 12m (33ft to 39ft) and even at its largest estimates this would be oversized for Tarchia.
|Larger Size Estimate|
|Smaller Size Estimate (image by Conty)|
13 June 2017
There are a number of articles and citations for Tarchia. There are a lot more citations than full articles online, but there are still articles that discuss the dinosaur, so those that learn by reading are not at any kind of disadvantage this week (i.e. there is plenty of material to read and learn from about Tarchia). The most important and useful articles that exist online as full articles are possibly the most important articles in the current body of literature for Tarchia outside the initial description by Maryanska. The first is the description of the junior synonym Minotaurasaurus ramachandrani which describes what the authors (Miles and Miles) interpreted as a unique and novel cranial structure unknown before the discovery of these remains. The second article linked here today is the Arbour, Currie, and Badamgarav, 2014 that re-describes both Tarchia and Minotaurasaurus (as well as many other ankylosaurs of Mongolia) crania interpreting similarities, differences, and variations within the genus. It is worth noting that these authors mentioned that Minotaurasaurus is a fossil lacking provenance and was purchased at a mineral and gem show but has been hypothesized to have been recovered from Mongolia by Dalton 2009. The authors consolidated Minotaurasaurus as the same species as T. kielanae, but they did interpret the remains of another animal, Dyoplosaurus giganteus, as similar enough to belong to the same genus and redesignated the animal as T. gigantea; I have not looked up how this species was erased from the taxonomy so cannot offer more as to why it is no longer included in the Tarchia family tree.
12 June 2017
11 June 2017
10 June 2017
|©Nobu Tamura; listed as Minataurasaurus|
08 June 2017
07 June 2017
|©Edyta Felcyn (Apsaravis)|
|©Edyta Felcyn (Apsaravis)|