STL Science Center

STL Science Center

28 May 2018

Bit Role Star

Rhamphorhynchus appears in two popular films for brief periods in each. The first, One Million Years B. C. is vintage Ray Harryhausen stop motion work with a very inaccurate version of Rhamphorhynchus attacking a Pteranodon. Despite its terrible inaccuracies it is an intriguing interpretation of the animal. Also it eats the Pteranodon nestlings, which is peculiar and very much outside of its inferred diet. The second appearance of Rhamphorhynchus that is probably better known is from Walking With Dinosaurs (Ep. 3 Cruel Sea) in which it is shown skimming the surface of the water for small fish. There are a number of reasons this is a strange portrayal, and time permitting, we will get into them later this week. For now, though, enjoy these two clips:

27 May 2018

Night Flying

If a niche exists in nature, some animal somewhere is, was, or will be an expert in that lifestyle. During the Jurassic Laurasia, the northern supercontinent, was populated by a number of pterosaurs that possessed different body shapes and populated different niches. Many different characteristics of these fossil flyers have led researchers to many inferences of diet, flying style, and even time of activity; for example, the scleral rings and orbit shape of Rhamphorhynchus are a key characteristic leading researchers to infer a nocturnal lifestyle. The long-tailed pterosaur has been discovered across Europe and in parts of Africa in deposits that represent shoreline and off-shore environments. The localities, along with cephalopods and fish that have been recovered from both gut areas and coprolites (fossilized feces), point to Rhamphorhynchus as an ocean-going pterosaur. Consisting of three recognized species (R. longicaudus Münster, 1839 (type specimen) , R. muensteri Goldfuss, 1831 (originally Ornithocephalus) and R. etchesi O'Sullivan and Martill, 2015), Rhamphorhynchus was a small (1.26 m, 4.1 ft long; wingspan: 1.81 m, 5.9 ft) needle-toothed pterosaur lacking a crest and possessing a long tail, something pterydactyloid pterosaurs (the kind most people think of when they think of pterosaurs) noticeably lack. The tail, in fact, is the origin of the specific epithet of the type species, R. longicaudus.
Louis Figuier, 1863

22 May 2018

Yates Description

As with many dinosaurs, there are a number of papers that mention Dracovenator, far more than the number of papers that actually focus all of their attention on our featured dinosaur. The description of Dracovenator by Yates (2005) is detailed, including line drawings, detailed photographs, and even a character list of attributes at the end of the article. As with many descriptions, the article is a little dry, but that is the nature of descriptive paleontology, so it does not make the article bad or otherwise lacking some sort of thrill found in other papers describing fossils. I am kind of a fan of the image of the juvenile fossil displayed upright as it is not often that we are shown the flat side of fossils in papers in this manner.

Yates, A. M. (2005). A new theropod dinosaur from the Early Jurassic of South Africa and its implications for the early evolution of theropods. Palaeontologia Africana 41:105-122

20 May 2018

Dragon Hunters

Dinosaurs and fossil hunters have been referred to as dragons and dragon hunters for centuries now; however, there is only one dinosaur whose name means "Dragon Hunter": Dracovenator regenti Yates 2005. A dilophosaurid discovered in the South African foothills of Drakensberg ("Dragon's Mountain": Dutch), Dracovenator consists of cranial material from early Jurassic rocks near the borders of Lesotho, a small country contained within South Africa. The characteristic shape of a dilophosaurid skull is apparent in the remains of Dracovenator in both the adult (holotype) and referred juvenile materials (reassigned from Syntarsus to Dracovenator by Munyikwa and Raath 1999). The estimated size of Dracovenator, extrapolated from related animal sizes and the cranial material available, is between 5.5 and 7 meters (18 and 23 ft) from snout to tail and weighing upwards of 400 kg (882 lbs).

18 May 2018

Dynamic Images?

What is the most dynamic, awe-inspiring image of Tuojiangosaurus that one can find on the internet? There are a near infinite number of opinions regarding which image and why any particular image might be the most beautiful or amazing image of Tuojiangosaurus. The images could come from anywhere also. This includes skeletal mounts, 3D video game renders, ink drawings, and any other media one can think of. My personal favorite was a hard choice this week. I always love the old-fashioned (like Charles R. Knight style) sorts of drawings, but Tuojiangosaurus was not discovered until 1977. Conversely, I appreciate really well done computer generated media as well, of which there is plenty representing Tuojiangosaurus. The image I have chosen as my favorite of the lot comes from the latter category today, and specifically it is attributed to Román García Mora. Even though the artwork is attributed to Mr. Mora, it does not appear on his website, linked above. Maybe more unfortunate, the image was originally found on a fourth party site and therefore even farther from the artist's control.
©Román García Mora

14 May 2018

Fun to Type

Tuojiangosaurus is actually fairly easy to spell after the first two or three times you type it out: fun personal observational fact/opinion that I just decided upon. If anyone disagrees, I can completely understand why, but give it a few more tries before you give up. Additionally, despite searching the blog the other day to see if we had covered this animal before and for some reason nothing seemed to show up, I noticed today that we had covered it, six years ago. However, revisiting old friends now and again is always interesting and fun. An even more fun fact about that time is that I found out that I was accepted to the biology graduate program at Fort Hays, which means that Tuojiangosaurus was the first dinosaur we discussed during my non-educator focused graduate career. Pretty neat stuff there. Anyway, on to the important aspects of why anyone opens this page on a Monday: movies about the animal we are featuring this week.

Back in 2012 there were not many, if any, videos of Tuojiangosaurus on the internet, a point that I noted by sharing the one short documentary I could find at the time that discusses Tuojiangosaurus in any detail (the 9:18 clip is featured below again today and our stegosaur appears at the 3:00 minute mark). Tuojiangosaurus now, though, appears in video game clips and short movies all over YouTube, but that is hardly the end of its representation online in video format. There is a video of an animatronic version of the Chinese stegosaur from the Henry Doorly Zoo (in Omaha, NE) and Brookfield Zoo's (in Chicago, IL) Dinosaurs Alive exhibits. This animatronic dinosaur exhibit can be found at many different zoos under the same or slightly different names at different times of the year; one of the series of photos I have shared here in the past was from the Memphis Zoo's version simply titled "Dinosaurs". The Tuojiangosaurus featured in the exhibit is a little less like the actual fossil than we would like. However, it does encourage people to look up the dinosaur and see what they should really be seeing (as opposed to what they did see), which is a good place to start educating more people about our favorite fossil animals. In a similar vein, this video from the Dinosaur Quest at the San Antonio River Mall shows fossil casts rather than animatronic dinosaurs.There are countless video game videos of the dinosaur surrounding the links shared here and the short clip below, but I will leave these to the reader to discover at their leisure or desire.

13 May 2018

Small Stegosaurs

Thinking and writing about Ceratosaurus over the last week made me think about the animals that would have been food items for Ceratosaurus. One of the most prominently discussed and featured food items for Ceratosaurus and its contemporary Allosaurus was the western North American dinosaur Stegosaurus. We have written about and discussed Stegosaurus here at least once by itself and a number of times in reference to other dinosaurs. We have also discussed some of its closest relatives (such as Kentrosaurus), but we have somehow missed talking about one of its best known, Asian, cousins, Tuojiangosaurus multispinus. The name refers to both the multiple spines along this stegosaur's body and its discovery near the Tuo River of central China within the Sichuan Province (yes, where the cuisine originated from). Watch the video below to learn some more important facts about Tuojiangosaurus:

10 May 2018

Ceratosaurus Anatomy

Ceratosaurus has an interesting set of ridges and horn-like structures on its skull that gave two of the species their specific epithets: C. nasicornis ("nose-horn") and C. magnicornis ("large-horn").  The purpose of the horn was originally thought, by Marsh, to have been a "most powerful weapon" used by the theropod in both offensive and defensive matters. Many others agreed including Gilmore in 1920, Norman in 1985, and Paul in 1988. To be fair, Norman and Paul were more specific, arguing that the horns may have been used in intraspecific combat and headbutting. Rowe and Gauthier (1990) put forward a display only function for the horns, which appears to be the most popular hypothesis concerning Ceratosaurus horns.The assumption with these rugosities as display ornamentations often includes discussion of potentially brightly colored soft tissues covering and otherwise associated with the osteological structures.
American Museum of Natural History
Photo by Wikicommons user Daderot, released into public domain under Creative Commons CC0 license

08 May 2018

Balancing Papers on Horns

Ceratosaurus is the star of a couple of books (I am a fan of Charles Gilmore's description of North American carnivores from 1920). More importantly, Ceratosaurus is the star of a large number of scientific studies. The large volume of work stems in part from some of the interesting ways in which the fossils have been discovered. These studies include unique discoveries that were somewhat unexpected in places like Portugal and Africa. Possibly the largest concentration of Ceratosaurus skeletons that are known and have been recovered and prepared come from the states of Colorado and Utah; there are a number of other finds in Wyoming and other areas of the North American West as well. Reading the numerous descriptions of new finds could take one all day, but it may be worth it. I offer here a few older readings from Hay, Marsh, and Madsen that describe new finds and restorations of Ceratosaurus skeletons. Other options worth reading include Henderson's ecological study centered on skull and tooth morphology and Bakker and Bir's contribution to the book Feathered Dragons edited by Currie, et al.; a chapter titled "Dinosaur crime scene investigations: theropod behavior at Como Bluff, Wyoming, and the evolution of birdness". Though not always a popular character, their chapter is well written and an interesting interpretation of theropod feeding locations and the clues left behind.

07 May 2018

Facts and Movies

Ceratosaurus is a charismatic theropod dinosaur. Aside from how much I like Ceratosaurus personally, it is very apparent that Hollywood and other paleontologists have a great deal of affection for and interest in this genus. That has led to many podcasts, movie roles (yes, even in the Jurassic Park no one likes), and appearances in documentaries. Some depictions of Ceratosaurus shown here are almost magical; by that I mean that often Ceratosaurus is portrayed as a dinosaur with a unicorn-like horn. The facts and fossils show that the horn is not much like a unicorn's horn at all, and, as stated yesterday, was quite variable across species within the genus and individuals. In One Million B.C. Ray Harryhausen said of his Ceratosaurus, its horn, and the other dinosaurs of the movie that his creations were not for "professors... who probably don't go to see these kinds of movies anyway."

06 May 2018

Favorite Oldies

One of my favorite theropod dinosaurs is the medium sized so-called "horned lizard" Ceratosaurus. A genus consisting of three recognized species (C. nasicornis Marsh, 1884 (type), C. dentisulcatus Madsen and Welles, 2000, C. magnicornis Madsen and Welles, 2000) and one junior synonym that has been applied to the type species, Ceratosaurus was a Jurassic carnivore sharing the landscape with large sauropods, stegosaurs, and allosaurs. Known from North America, Europe and Africa, Ceratosaurus was a widely distributed and successful predator eclipsed during its existence only by the larger and equally successful Allosaurus. Though we consider Ceratosaurus to be a medium sized predator in the context of all theropods, at 5.69 m (18.7 ft) long; C. nasicornis is fairly large; the largest species C. dentisulcatus is estimated at 7 m (23 ft) long. The feature responsible for the name of this dinosaur is a large rugosity on the dorsal surface of the muzzle that appears to some to look like a horn; the type material was more horn-like than some of the later discoveries, but for the most part these rugosities are variable and can look like anything from horns to small ridges. Because we have so many remains of these animals, their ecosystems, and their contemporaries we know a lot about their life history, ecology, and the world that was around them. We also know enough about their feeding ecology that we can build awesome museum displays like this one at theNatural History Museum of Utah.

04 May 2018

The Scary Face

When the characteristic feature of your existence, as a fossil that is known and described in science, is that the entire legitimacy of your existence in our knowledge is tainted by potential theft and other impropriety you do not get overburdened with a lot of respect or investigation. Of course fossils are not people so the skull of Minotaurasaurus does not actually feel any shame, guilt, or worry about the provenance of its discovery or how it was whisked away from Mongolia (or wherever in Asia it originated). The people involved, regardless of their status as buyer or seller, are subjected to arguments from both sides of the controversy; factions do indeed exist that say that keeping the fossil in a private collection is as morally correct as it is to rescue a fossil from a private collection. Articles and opinions are everywhere online and in paper journals as well as in newspapers and magazines (two of these linked articles are about the same specimen). Not all of these issues arise in other countries either. The United States of America has its fair share of dinosaur fossil legal battles throughout its history; the ownership of Sue the T. rex being the most famous one that I can think of right away.

Minotaurasaurus is not a Tyrannosaurus and it is not a fossil of North America. Instead, it represents a real and, unfortunately, growing problem, even if we do not hear about it daily in the news. The skull is actually very interesting because it looks a lot like many other ankylosaurs we knew of previously and this has caused a lot of researchers, such as Victoria Arbour and Phillip Currie, have reassigned Minotaurasaurus to another taxon, Tachia kielanae. Another study upheld the original description and nothing else has surfaced since that time. Regardless, the skull is not in a museum where all of these researchers can look at the original material and come to a solid conclusion. Until it is they, and we, will have to make due with casts and character lists and some photographs to compare the skull to other animals. Description can be tricky though, so this description may be contentious for a some time to come, unless another animal is discovered and can be studied more directly.
Photograph of a cast of the holotype material. Borrowed from Victoria Arbour's blog here.

01 May 2018

Two Sides to Read

The description of the lone known skull of Minotaurasaurus is hosted online. Miles and Miles 2009 was published in Current Science (an Indian journal published in conjunction with the Indian Academy of Sciences), not necessarily because it was not good enough for some of the typical venues of fossil description (such as the Journal of Vertebrate Paleontology), but because it was very controversial. An initial attempt to publish in a Polish journal was met with rejection. The rumor about how the skull was purchased is that one of the authors told the buyer it would be named after him if purchased and it was purchased without papers of provenance because they do not exist, not because they were lost or misplaced. The fossil is Mongolian but it was prepared in the United States of America and sold through a Japanese based fossil dealer. Nature published an article summarizing the trip that the fossil has taken to become a published fossil shortly after the description was released. The New Yorker preceded the Nature article in releasing a story on fossil dealers and the fossil trade. Their article goes into details about illicit fossil sales and discusses the seller of the Minotaurasaurus skull, possibly connecting him with another illicit fossil sale of Tarbosaurus.