That Lack of Kid Related Things

Rajasaurus has joined the ranks of so many other unfortunate dinosaurs that do not have anything to present to the children of the world. That is not completely true I suppose, they have being a dinosaur to offer to children. There are a lot of dinosaurs in the world though, and Rajasaurus is not as well known as others, and has, therefore, not been the subject of many child related internet pages. Science Kids, the New Zealand based science website does mention Rajasaurus, in short dialogue, but then has a very basic Abelisaur illustrating the page, which is kind of sad. They are passing on the knowledge though, and that's a start. Project Exploration, mentioned earlier, has a lot of good information for the children of the world and, most importantly, labels it out nice and concise for children to read. There are no coloring pages labeled as such, but yesterday's entry has a black and white image that could be used surely.

The Illustrated Rajasaurus

There are quite a few very similar illustrations of Rajasaurus floating around on the internet. The reason that they are so similar is that the majority of them are based off of the exact same skeletal diagram. There is nothing strange or unique about that; it happens all the time in dinosaur illustration. What is different about it is that many of the illustrations have their own identifying characteristics. This Rajasaurus, for example, has longer arms that are anticipated for Rajasaurus. In fact, they almost appear like the arms of Allosaurus instead. The bump on his head here shows just how small the actual protuberance was; it appears to barely just above the eye ridge of Rajasaurus.

Posed in the same basic position, this Rajasaurus also has somewhat elongated, though shorter than the first illustration, arms. The protuberance on its head is a lot more showy in this illustration of Rajasaurus. In fact, in this illustration it is very pointed, whereas it is thought to have been a large rounded off knob of bone much more than a keratin sheathed horn that elongated a great deal off the skull. Like other Abelisaurids, it is believed the protuberance was used as an identifier as well as a headbutting device during mating and territorial rivalries.

©Todd Marshall

This illustration is the most action posed shot today. Not only that, it is the only one that possesses the arms as they are thought to be after more extensive study of Rajasaurus and Abelisaurids in general; meaning this is the most recent interpretation amongst the three illustrations today. The neck wattle is a nice touch, but of course we do not know much about the soft tissue of dinosaurs unless it is a mummified dinosaur, which Rajasaurus was not. The protuberances and other bumps and ridges along the skull are portrayed very sharply here. The headbutting horn on the top of the skull is a little sharp looking in this illustration as well, but we have already discussed how it looked on the skull itself as taken out of the ground.

A Princely Lizard of India

©Dmitry Bogdanov

The "Princely Lizard of Narmada Valley" was a rather large Abelisaurid theropod. This dinosaur was a lot like Majungasaurus, living in Madagascar, which had separated from India 20 million years prior to the date in the fossil record at which Rajasaurus narmadensis was found, and was a close relative of the former dinosaur. Being a close relative of Majungasaurus was not enough to justify the classification of Rajasaurus as an Abelisaurid, but the bones itself, in particular its nasal and frontal bones and protuberances found on the skull as a whole pointed not only to the Abelisaurid famly, but also to the subfamily which includes Carnotaurus (the Carnotaurines). Thus Rajasaurus is not only an Abelisaurid genus, but it is an Abelisaurid Carnotaurine genus (crazy hard to pronounce science!). The original skeleton is comprised of a complete skull and approximately 70% of the rest of the skeleton; an extraordinary find for fossil hunters with an animal as large as Rajasaurus, which measures in at "about 7.6–9 m (24.9–29.5 ft) long, 2.4 m (7.9 ft) in height, and weighed about 3 to 4 tons" (Wikipedia). Rajasaurus, like other Abelisaurids, has a protuberance on its head made mostly along the frontal and nasal bones to create one low horn coming out of its face, which also makes it unique in the Abelisaurid family.

Dinosaur King Again

Arrhinoceratops, like many dinosaurs that have been discussed here in the past, has had a trouble hitting the popularity track running. Though it was mislabeled in videos on Monday not once but twice, it does still have some amount of popularity that we can positively identify. That popularity comes from its inclusion in the world of Dinosaur King where it is actually fairly well known, having had three cards attributed to it in the game and being a video game creature for the series as well. The dinosaur is mentioned many times in books, though they are the scientific books of paleontologists, not the kids books that often end up most popular.

Arrhinoceratops and That Unique Nose

Taken from Paleopedia

Arrhinoceratops has a rather interesting nose horn. There is no debate about whether its nose horn was a shielded boss like Pachyrhinosaurus or if it was actually a Triceratops-like horn which eventually sloped upward. The nasal horn of Arrhinoceratops was originally described as not existing and instead interpreted the small bone on which the horn's keratin sheath would have developed simply as a deformity of the skull due to compression during fossilization. The horn is indeed small and it barely angles upward; in fact, the bony core of horn actually juts nearly directly forward off the sloping nasal bone. Arrhinoceratops has been cited as possessing evidence that the nasal horn core is a separate ossification from the nasal bone, though it has been doubted that this is true.  The nasal itself is somewhat thin with, as in all Chasmosaurine skulls, an extremely large pair of nares (hole for the sinus and olfactory organs). The frill of Arrhinoceratops is also very typical for Chasmosaurs and is of a moderate length, about in the average size range for a moderate to larger Chasmosaur. Chasmosaurs as a group are the largest, as well as the youngest, group of Ceratopsians and therefore, even without any postcranial skeletal elements to go by, it can be safely assumed that Arrhinoceratops would have been a rather large animal. Estimates of size based on skull to body ratios of other Chasmosaurs and the skull of Arrhinoceratops place the animal at approximately 6m (20ft).

Arrhinosaurus in Print

For a little while there, about 60 years or so, we had a second species of Arrhinoceratops (Gilmore 1946). In 2005 that was overturned and the Torosaurus thought to be an Arrhinoceratops was returned to his genus (Sullivan, Boere, and Lucas 2005). The papers reporting first one way and then the other are, sadly, not available online as anything more than abstracts. The truth of that study of Gilmore's, however, is that the paleontology community was always a little skeptical of the genus shift and therefore most papers in the interim that mention Torosaurus utahensis refer to it as "Torosaurus (Arrhinoceratops?) utahensis" and never specifically call it an Arrhinoceratops. The original paper for Arrhinoceratops by William Arthur Parks (Parks 1925) is equally elusive; and that is more on account of its age than anything else as older papers tend to not make it to electronic media very often. Parks was a lot like Lawrence Lambe, a fellow Canadian, and was quite prolific at dinosaur naming in the 1910-1935 era, even naming new species into the last year of his life, sadly, though we do not have his naming paper for Arrhinoceratops. However, in a non-related note, Tuomas Koivurinne told me yesterday I can share his wonderful painting of Arrhinoceratops engulfed in a forest fire. It's pretty fantastic.

©Tuomas Koivurinne

Mislabeled and Unshown

Arrhinoceratops is not in the movies. There are two clips of video out on the internet that claim to be Arrhinoceratops, but neither is. One is a Discovery channel video, believe it or not, that is mislabeled somewhat atrociously considering the clip is narrated and from a show that they ran a few years ago, meaning the designers of the website should be getting handed the titles and videos by people with access, eventually down the line, to the scripts, or at least transcripts of, the original show as it was aired. It's a bit crazy really. Regardless, the animal actually shown in the clip hosted by Discovery is Zuniceratops, an earlier, smaller (about the size of a cow) Ceratopsian that lived thousands of miles to the south in what is now New Mexico. The second clip is a home video of, I think, a roadside attraction known as Dinosaur World that operates in three places in the U.S. Again, regardless, the dinosaur in the clip was not Arrhinoceratops, but what looks to be a rather odd Pachyrhinosaurus, I am not even going to link the video, it's a weird mislabeled model, but anyone that is interested can go to Youtube and type in Arrhinosaurus and it pops up right away. It is a disappointing day in terms of dinosaur movies today, but maybe someone reading does have a video that they will not mind sharing; maybe not today, maybe not next year, but maybe someday!

Coloring and Drawing

Arrhinoceratops has KidsDinos material, which I always love to share with the children around here. Additionally, there is a TLC Family page on how to draw Arrhinoceratops. Whenever I try to draw anything from a "how to draw" book or website it always comes out funny, but that is an activity that the artistically inclined children in your lives will love to be a part of. For children that love to be artsy, but are not daring enough to draw their own dinosaur there are two coloring pages that they can color today. There is also Dinosaur King material, for card game loving kids, but there are no toys that come up readily in searches. Here are today's coloring sheets:

Arrhinoceratops Poses for A Painting or Two

©Nobu Tamura

Like most ceratopsians, it is assumed that Arrhinoceratops lived in moderate sized herds or small family units at the very least, like modern elephants. The reason that an animal like Arrhinoceratops would not want to live in a very large herd has more to do with the sheer size of the animal. Arrhinoceratops was approximately 6 meters (19.7 feet) long and filled most of that length with muscle and belly. How do we know it was so long considering that we have found only a skull to describe this dinosaur off of? The powers of educated guesses and estimates based on other ceratopsian skeletons and understood ratios between skull size and body size have given us a fairly accurate way to hypothesize estimates like this. All said and done, Arrhinoceratops was probably too large for a large sized herd. A family unit of two mothers and a father, or as elephants are wont to herd as three to four mothers and their children typically, could easily care for three to four young and keep them safe from predators with their size and weapons.

©Sergey Krasovskiy

Speaking of those babies there, the number being so small in a herd makes sense. It makes a lot of sense actually. Large mammals have small numbers of young because they care for them and raise them as well as possible in the dangerous wild. Assuming that all dinosaurs always laid eggs, some of those eggs would not have hatched or may have been eaten and the tiny, by mom's standards, pups may have faced predatory dangers and the clumsiness of adults from the moment they emerged, further reducing the chances of survival to herd-on-the-move living size for ceratopsian babies. Therefore, if these three babes here are all that survived of one clutch of eggs, a large dinosaur like Arrhinoceratops may actually be coming out ahead of the game as opposed to how we think of modern mammal reproduction numbers and mortality. I like to think, though, that some of our dinosaurian friends may have evolved past eggs a bit additionally. Not all lizards and snakes today lay eggs, some have live births, and I see no reason why an Arrhinoceratops could not have had a live birth, tail first of course!, and that each one of these little pups could belong to one of the adults illustrated.

A Little Naming Deception

A dinosaur known only from its skull, Arrhinoceratops brachyops is a Chasmosaurine dinosaur that is closely related to Torosaurus. It has only been found in Canada and the initial find, a distorted, due to crushing pressure, skull, lacks its lower jaw and has absolutely no postcranial skeleton attached to it. The lack of skeleton is disturbing because its close relation to Torosaurus could lead some to believe that Arrhinoceratops is another form of Torosaurus and not its own genus. Thankfully, however, it possesses enough differences to be considered both an adult and distinctly different from Torosaurus, and Triceratops, and so will not be mashed into the other genus as has happened in the recent past (the mass opinion is still far from consensus last I heard a debate about those findings). Regardless, one of the things that sets Arrhinoceratops so far out on its own is the nasal horn that it possesses which is little more than a forward facing nub of bone sheathed in keratin. The name Arrhinoceratops means "No nose-horn face" and the name was coined because the initial description mistook the small nub of bone as a part of the distortion caused by the skull's crushing during fossilization. The brow horns are very ceratopsian in nature, curving first up then forward and outward. The frill is typical also; sweeping backward and up to cover the neck with multiple fenestrations to lighten the weight of the parietal and squamosal bones. Any anatomy aft of the neck frill is a guess based on the anatomy of other ceratopsians, as is the lower jaw, which was not found with the original skull either. The general Chasmosaurine structure of the tail, which was rather short compared to other ceratopsians, would have made Arrhinoceratops appear like a giant pig with an unwieldy head; a dangerous unwieldy head. The legs would have been of a moderate size, lifting Arrhinoceratops well clear of the ground, and would have been thick with muscle, allowing bursts of speed in defensive or rival-bashing behaviors. It would have been a heavyweight wrestler in its day, basically.

On the Ground or In The Trees

Bambiraptor, whether a ground dwelling or tree living animal, has made its mark in popular culture. This is partly because it was initially found by a teenager and partly because the majority of science agrees that it was a feathered dinosaur. Even as a ground living bird Bambiraptor would be just as interesting to the world as it is as a link between birds and dinosaurs. The fascination with Bambiraptor has created a desire for a number of books geared toward children, teens, and adults as well. There are books of dot-to-dots along side in depth debates about the origins of flight in birds on the list of books which are about or discuss Bambiraptor in detail. Bambiraptor has also made it into the crafting world, and anyone can do these honestly; I built a reindeer a while back from the same website for my classroom at the time. One of its largest impacts, though, has been in the gaming world. It has been created in Spore, like many other dinosaurs, and has also appeared in Zoo Tycoon 2 and Tiny Village. Spore is up to the creator to decide how accurate their animal will be. Zoo Tycoon aims for as much realism as it can fit in. Tiny Village, on the other hand, is a cellphone based game adapted to iphones and Android phones about making a caveman village with prehistoric pets, and the prehistoric animals are fairly whacky looking for the most part. Check each one out:

Spore

Zoo Tycoon

Tiny Village images of Bambiraptor

Doing A Little Reading

Bambiraptor has a furcula, or a wishbone, and shares many other avian features with modern birds, almost more features than it shared with other dinosaurs. Much of the pelvic girdle and legs is highly reminiscent of other Dromaeosaurs like Velociraptor and Deinonychus. The fact that Bambiraptor has such a mixture of characteristics of both birds and dinosaurs is par of what has led to debates within the paleontology community, as well as outside, as to the exact nature and placement of birds in evolutionary history and their relationships to dinosaurs. There are those that claim all of the animals in the Dromaeosauridae as dinosaurs, and there are those that claim they are birds; some Creationists, by the way, claim that there is no argument and that no dinosaur ever had feathers, many citing Alan Feduccia's work and the argument in the paleontology community as 100% proof that paleontologists are making everything up. That is not really fair I suppose, it was mainly just this one article that claimed all that, but there are plenty that agree with the article. Feduccia's skepticism about the origin of birds lying in dinosaurs is supported by some prominent paleontologists in one fashion or another and Bambiraptor is one of those battlegrounds on which the two opposing sides fight, sadly. In part it is the make up of the bones of the Dromaeosaur family that help fuel arguments that they were only large flightless birds mimicking dinosaurs, which is an interesting argument, and part of the argument is much, much older and has to do with when and where dinosaurs and birds split originally in their independent evolutions.

The naming paper has a large section of the discussion devoted to discussing those bird-like elements possessed by Bambiraptor but, most likely due to the highly diversified authoring team, there is no directed dinosaur or bird conclusion as such. David Burnham would go on a few years later to present a thesis which presented the arguments for and against a dinosaur bird link, he also called Bambiraptor "a terrestrial runner" whereas the majority of other sources consider Bambiraptor an arboreal carnivore. His thesis, in the end, concluded the argument the way that Feduccia and Larry Martin have been siding on the argument; that dinosaurs and birds developed alongside one another and that birds did not come from dinosaurs. The evidence of the argument, we are, as the general public, assured exists, but we are not really granted access to the evidence either for or against this argument. The majority of what the public believes, therefore, must come either from the media, which is certainly dinosaur-bird heavy, or from reading or listening to the two sides of the argument and making our own opinions. I would like to keep the old theory as my own, but we will see what I see as I continue down this career path, and as such, I am trying to keep an open mind; though for now I still think of Bambiraptor as a dinosaur that may be a transitional form lingering on during the rise of true birds.

Late Start to A Paper Filled Tuesday

Thanks to our friend over at The Theropod Archive we have two places the original naming paper can be found for Bambiraptor. Scroll up just a teensy bit from this link, looking under Burnham et al., and you can find it rather quickly. I do have to say, though, that typically, as of late at least, links to Currie's PDF's on his homepage at the University of Alberta have been outdated or completely erased, so my advice is to go with the top PDF rather than the bottom one. Since I am running later than usual today I have not had time to read over it, but I am hoping to be able to this evening so I can discuss it in some detail tomorrow (I also have a test to study for and papers to grade, so it should be a fun filled day). Another paper I want to find time to read, also by Burnham, is hosted by the University of Kansas and is about, as Burnham's title states, Maniraptoran "Dinosaurs." Burnham's quotations are what make it of interest to me because they indicate, obviously I feel, that he is going to say something about the clade being, more than likely, much more avian than reptilian and I'm wondering if he may pose a separate evolutionary track. I just hope I have time to read it sometime soon. Taylor and Francis, hosting the Journal of Vertebrate Paleontology, which you have to subscribe to or buy per article, have a hosted paper on comparison of forelimbs of Deinonychus and Bambiraptor by Phil Senter published in 2010. The abstract looks a little technical so I imagine the article itself is a bit specialized, but I'll give a look-see sometime soon, though I will not be writing anything about it within the next 24 hours for sure.

Behind the Scenes with Bambiraptor

Bambiraptor is behind the scenes in most documentaries. Once in a great while it will pop out without any warning or explanation as a nondescript feathered dinosaur in the background or in a trailer, but it is never discussed in depth in the course of a documentary. In part this is sad, mostly because it is an interesting dinosaur regardless of the debates about feathers and its placement in the family of Dromaeosaurs. Part of why it is not featured is more than likely on account of how little we do know about the animal. The skeletons we have have given us a lot of information, but there is a lot more to collect and there is the issue of feather evidence. Once there is a little more evidence for feathering there may very well be more documentaries in the future, but not for a while it seems.

Bambiraptor: A Fawn For Kids

I actually found a website today that denounces Bambiraptor as a feathered dinosaur and goes further to argue that no feathered dinosaurs other than those which have legitimate fossil feather impressions existed with feathering. It goes on to argue that evidence of quill knobs are not enough evidence to make a statement about a dinosaur having feathers as well. In the end the whole website boils down to statements that twist words such as paleontologists saying things such as "Shuvuuia likely possessed a coat of feathers" and turning it into a statement, which the author says "in English means" that "Therefore, this dinosaur must have had bird feathers" even though the language above clearly states that the animal's covering is an educated, hypothesized, guess. The author states that the book consulted for the post never offers children a look at the fossils themselves and asks children to trust scientists and their "faith" that they're right. Enough about this sort of thing today.

I think given the nature of children they can decide if they believe this dinosaur had feathers all on their own. They can look at the Dinosphere at The Children's Museum of Indianapolis' information site. They can also consult theDinosaurs.org's information about Bambiraptor. This site actually shows the fossils that have been found for children to look at, including the holotype skeleton which shows no feathering at all in it. There is not really anything to color today except this one picture, but it is better than nothing at all. Let the children look at Bambiraptor today and make their own conclusions from the fossils and everything they read, I am sure that they will make some very clever observations and surprise everyone no matter what they believe Bambiraptor looked like while it was a living, breathing animal.

Taken from http://www.dinosaurier-interesse-2.de/

Bambiraptor the Feathered

Artist Unknown at this time

Dromaeosaurs are expected to have feathering these days. There is not a single thing wrong about feathering on Dromaeosaurs on account of the fact that we have fossils that have feathers. The exact nature of the feathering on Bambiraptor, at this time, is not known, however. The hope for the future is, of course, that there will be known feathering from fossils of some kind to support the theory of a feathered dinosaur. The reasoning, or part of the reasoning, for the original feathered illustrations came from the ideas of paleontologists that Bambiraptor appeared to be an arboreal hunter of small agile creatures it could watch from above such as small mammals and lizards living on the forest floor.The small size of Bambiraptor would certainly have allowed it to scale trees more easily as powered flight in this dinosaur was not a reality. Gliding was probably not a reality for an animal like this either at this stage in the development of the dinosaur-bird lineage.

©Scott Hartman

The holotype, possessing the majority of its bones, has led to many other clues about the tiny dinosaur. Its teeth, for instance, are  recurved like those of other Dromaeosaurs which has led some paleontologists to look at diet and how Bambiraptor fed itself. Given its small stature swallowing smaller animals whole would, while feasible, probably be somewhat problematic as it did not have the largest teeth to hold the prey in place as it shifted the prey for swallowing. One alternative that has been voiced is that the arms and wrists of this dinosaur were supple and long enough to actually hold prey up to the mouth, allowing Bambiraptor to eat its prey items the same way we eat cheeseburgers or small mammals eat their food. If this is indeed the case that would be quite a unique situation in the dinosaur world, given that almost all other predatory dinosaurs possess arms far too short to reach their mouths, let alone to feed themselves. The hand alone on Bambiraptor is fairly enormous for its size as a dinosaur.

©Puntotu

Alternative images of Bambiraptor are fantastic to look out. I could pick out typical feathered Bambiraptors all day long for this post, but none of them are as interesting as this slightly different modeling of the dinosaur. There's something to be said about the idea that there were more than likely one variation of a dinosaur species and the portrayal thereof. Often we find a very mundane mixture of coloration in feathering illustrations, however, here we have a typically forest-colored feather scheme replaced with a much more gull-like coloration scheme. The idea that another variation of Bambiraptor may have been more of a shoreline animal is more interesting than usual in part because there are very few trees for it to sit in along an ocean shoreline. Along the interior seaway in North America Bambiraptors in the forests as well as along the shore may have been a daily sighting for other dinosaurs going about their business. This different coloration may have belonged to a second species, if it had in fact existed, or it may just be one of many possible colorations that could have been found in Bambiraptor. Perhaps in the future we will be able to find out.

Bambi Goes Cretaceous

Not the correct Bambi

Bambiraptor feinbergi was certainly not a deer, nor was it cute and cuddly, despite its small size and birdlike appearance; feathering in Bambiraptor is an educated guess, though accepted by the vast majority of the paleontology community given its perceived habitat and familial relationships in the Dromaeosauridae which is known from many different fossils to be a feathered family more often than not. The original specimen of Bambiraptor is a juvenile discovered by a juvenile, 14 year old Wes Linster, in the early 1990's. Due to its small size and similar appearance to other known skeletons, it was initially believed to be a juvenile of Saurornitholestes, but was, after the original description and the discovery of more partial skeletons, retained in a new genus and species. The holotype skeleton, in fact, is 95% complete, which is extremely rare, while the subsequent discoveries are far less complete; they comprise a few partial adult skulls and skeletons that are noticeably, but not much, larger than the juvenile. That juvenile rocks the scales at a whopping 4.4lbs (2kg), estimated, and approximately 90cm long, with some tail vertebrae missing which would probably make up about 10cm more, making the whole juvenile approximately 1 meter long (about 3.3ft). Thought to be arboreal, the Bambiraptor juvenile had a brain about the size of a small bird like a Blue Jay or Sparrow, making it fairly smart in the terms we generally think of for dinosaurs. It's brain, though, is thought to have been geared toward agility and higher thinking skills, as high as most birds get of course remember, as these parts of the brain cavity, particularly the cerebellum's area in the brain cavity, were larger than the rest of the brain.

Finally, the correct Bambi

Life at the Popular Watering Hole

Being bizarre works for Amargasaurus. It works so much that there are toys, PBS shows (as well as toys based on Dinosaur Train), and even Dinosaur King materials which feature Amargasaurus. In my opinion the kids' shows are more important than most other forms of dinosaur popularity, as I have stated many many times now. The reason for this remains that the children are the future of paleontology. Somewhere some child is taking in all the Amargasaurus materials that the world has to offer- Dinosaur Train, Dinosaur King, toys, coloring, Dinosaur King cards, Dinosaur King video games- and that child is going to grow up wanting to study that mysterious dinosaur. Amargasaurus is not showing up in the kitchen like some other dinosaurs, but it is still making quite an impact on the culture of the world in museums and animatronic shows, for instance. Some day, perhaps, we will learn enough about this dinosaur to make a sure guess about its soft tissue, and maybe some day we will even be lucky enough to find the rarest of the rare in dinosaur skeletons: a mummified Amargasaurus. Until that time, however, our imaginations and scientific information will have to continue to shape the many theories shown in the many adaptations of Amargasaurus in the popular world.

Amargasaurus and Those Spikes

Gregory Paul has come out, in 2000 actually the first time, and said that there is pretty much no way that Amargasaurus' spikes supported a sail structure; I have paraphrased grotesquely. I tend to agree with that idea, and with another part of his theory behind those spikes, but he raises one interesting idea which I find quite interesting and seems quite plausible that I, and most others probably, have not given much thought to when considering the neural spines possessed by Amargasaurus.One of the points of Paul's theory, mentioned briefly in his latest literary work The Princeton Field Guide to Dinosaurs, is that the neural spines, while used as a deterrent against large predators, could also be used to communicate. He notes that they "may have been used to create [a] clattering noise display" (page 188). Though his intent is to make the reader aware of this as an intimidation tactic, if this was a regular behavior for this species it more than likely would have also been used as an alarm to danger as well as way to recognize the presence of a herd or to call a herd; for example, in the case of an animal being separated during a predatory attack or having simply lost the herd while feeding. This would come in handy if studies (I'm looking for these purported studies actively) suggesting sauropod vocalizations were geared more toward hissing than lowing in the way of modern cattle are correct; sauropods have always had a rather decidedly bovine-like voice in Hollywood, so it is very hard to imagine them making hissing sounds actually. Paul does mention (page 37) that the long necked sauropods' long tracheas should have been able to create and emit low frequencies and therefore, using Paul's viewpoint, the rattling of the spines would have been an auxiliary mode of communication over distances rather than a primary form of communication.

Those spines, however, would probably have produced more of a thud sound due to their shape behind the cervicals. This is probably the reason that Paul has, in his illustrations, combined the idea of the camel-like hump behind the shoulders with the free keratin sheathed spikes on the cervical vertebrae. As noted yesterday in the linked SVPOW article, those dorsal neural spines are somewhat deep paddle shaped bones as opposed to the longer horn like cervical neural spines. It is pretty interesting actually that Amargasaurus, as interesting as it is already, would have such a diverse network of spines on its vertebrae.

References:
Paul, G. S. The Scientific American Book of Dinosaurs, New York, NY.: St. Martin's Press., 2000
Paul, G.S., The Princeton Field Guide to Dinosaurs, Princeton, NJ.: Princeton University Press, 2010

Amargasaurus in Print

Amargasaurus' initial print debut, a paper by Leonardo Salgado and Jose Bonaparte, is fantastically detailed with thorough descriptions of the bones found and compared to known Dicraeosaurid bones from Africa. Speculation into the use of some of the more fantastical elements of Amargasaurus' bones such as the tall neural spines are fairly ignored and the facts as they are take center stage. Some interpretation is made, but it retains the straightforward detail of scientific observation, which is very professionally done. Additionally, Salgado went on to write another paper some years later, this time with Jorge Calvo, examining the cranial structure of Amargasaurus. This paper I have not yet had time to sit and read, though I am quite interested to discover what new things Salgado and Calvo have to say about Amargasaurus since Salgado and Bonaparte's initial discovery. Hopefully I will have time today sometime and I can update this accordingly. Either way, don't ruin it for me by telling me in advance! As for newer papers, I have not found any readily available, though I have found snippets of comparison and discussion around Amargasaurus in other papers. One resource that is current are these blog entries on SVPOW about the shape of the neural spines and how an extant critter has offered some insight into the use of similar neural spines. The guys at SVPOW are real professionals too, and they offer some well thought out discussion about these topics, so they are certainly worth checking out if you never have.

Amargasaurus Movies

Amargasaurus is in quite a few amateur videos and it pops up in Dinosaur Train as mentioned yesterday as well as the World Book's Youtube channel. The amateur videos range from tributes to Spore videos with a few amateur question and answer videos in between. There are not any documentaries at present which feature Amargasaurus heavily or exclusively, even the National Geographic special on bizarre dinosaurs does not mention Amargasaurus too much, though the magazine article which preceded it did discuss Amargasaurus at length. Thanks in part to its rather strange composition, Amargasaurus has been re-created many times as an animatronic dinosaur, as it is clearly an attention getter and crowd pleaser when people can see it move about with its unique body. Interestingly enough, the version of the spines reproduced in the animatronic versions of Amargasaurus are typically of the use of the spikes as structuring for the sails along the back of the dinosaur. Lastly, there is a fairly awesome edition of speed drawing, we have shown this before with dinosaurs in the past, of Amargasaurus. Those of us not acquainted with speed drawing only need to know that it consists of a sped up drawing of something, in this case Amargasaurus. It is labeled, in the video itself, Camarasaurus, but it is very clearly not even close to being a Camarasaurus.

Amargasaurus: Keeping Children Busy All Day Today

You could almost leave your children alone all day today if they like Amargasaurus. We have dinosaur fact pages, as we often do, like KidsDinos and Science Kids. They can color until they're blue in the face today, of course most of the available black and white illustrations of Amargasaurus are not meant to be coloring pages, but since when has that stopped anyone? Coincidentally, my official standpoint on using other people's art to color is ask for the artist's permission to print it out and color it and please do not post it online, your coloring, without the artist's permission. Additionally, if you see your own art in that bundle of links and you don't want it there, let me know and I'll fix that. Anyway, the kids could also go buy some toys, with whatever they money they have earned or gotten as gifts lately, I mean. There are a lot of videos for kids to watch today too, not that you want your computer to babysit children ever. There is an episode of Dinosaur Train that has a segment on Amargasaurus which you can watch together on PBS and also has the science section with Dr. Scott at the end of the first half of the episode in which he discusses Amargasaurus briefly. In order to see the science bit though you have to watch the whole episode on Netflix or some other site, unless you want to wait for PBS to air that particular episode again. The World Book Youtube channel takes care of that if you have no way to see Scott Sampson's version of the science facts, though it is a little more in detail than the PBS short.

Amargasaurus the Beautiful

©Casliber, taken from Wikipedia

Amargasaurus, as stated yesterday, has a very intriguing array of vertebral neural spines arching above its neck and body. Here we have the naked spines, a cast thereof anyhow, which shows exactly how outrageous the neural spines are. There is nothing like an interesting adaptation which is as mysterious as it is jaw droppingly intriguing in a dinosaur. Regarding animals like the Ceratopsians we can make some fairly valid assumptions regarding defensive and communication, either of identification, mating purposes, or simply to identify members of a herd, intents of their frills and horns, with Amargasaurus, however, the intent of the neural spines is highly debated. There is certainly an element of display inherent in the spines regardless of the type of covering they bore in life, as we shall look at momentarily.

©ArthurWeasley, taken from Wikipedia

The first, and it seems most obvious adaptation noted by paleontologists, was that of a tightened skin membrane stretched between the neural spines to form a sail along the length of the body as far as spines stretched out of the back of Amargasaurus' body. There are many practical uses for a sail beyond the one trait, display and communication, we will consider valid with any of the three body types associated with the spines. One of these, of course, is thermoregulation. Regardless of how one feels about dinosaurs being warm-blooded, and there certainly are those that still feel that they are not, which is fine, the ability to help an animal as large as Amargasaurus to either cool down in summer or warm itself in winter simply by flushing more blood into the sail to be warmed or cooled is a theory that could definitely hold some ground. This, additionally, is a way that the dinosaur could have used the sail for communication as well; flushing eyespots in the sail at predators or appearing healthier during mating season by being more vibrant.

©Nobu Tamura

The Luis Rey illustration and this slightly older illustration from Nobu Tamura, always a friend to us here and always very willing to allow us to view his art, both champion the theory of Amargasaurus as it is. The spines themselves would not have been an active weapon; most likely the whip-like Diplodocid tail would have been used in that regard long before the dinosaur tried to use the neural spines in an offensive manner. Though it can be noted that spikes of bone covered in a keratin (think fingernails and rhino horns) sheath would have made a very formidable passive defense for the neck and upper torso of Amargasaurus. The length of the spines, in terms of display, would have been, basing this observation on extant animals' determinations of male prowess, the major factor in courtship displays and mating confrontations that ended without violence. Additionally, the spines may have had strong muscle attachment sites which allowed them to be flexed, like a cat's hackles for instance, in aggression displays towards rivals or predators.

Courtesy National Museum of History, London

The final proposed idea for those neural spines has been a camel-like hump down the length of the back in which the spines support the fatty tissues that make up the hump and give it some stability. This theory is not illustrated out as much as the other two theories, in part because it does not have the support that the other two theories entertain these days. The hump does have a logical use of course or it never would have been proposed to begin with and one explanation for the need for it would be an extended dry season in the environment in which Amargasaurus lived. In terms of ability to display with a hump like this, there is a little less ability to flash signals and to move the hump as there are in the spine or sail modifications that were previously discussed. The hump, therefore, would more than likely be mostly functional in terms of survival than communication.

Porcupine, Camel, or Sailback?

©Luis Rey

Amargasaurus cazaui. A sauropod dinosaur with enormous vertebral spines that, so far, have been speculated to be either horny sheath covered quills, the supports for a giant camel-like hump, or the supports for an enormous sail that could have been used for thermoregulation or display. The fact that any of the three was probably used in some sort of display tactic is a good possibility though either to ward off predators or attract mates or perhaps both. Amargasaurus is  another southern hemisphere dinosaur, discovered in Argentina, and dating to the Early Cretaceous time period. It is a single species genus and a member of the family Dicraesauridae, which includes two other genera and belongs to the superfamily Diplodocoidea, which obviously includes in its ranks Diplodocus and Apatosaurs. All of these animals are considered "whip tailed" meaning that Amargasaurus most likely possessed the same type of thin gracile tail which could be used like a whip in defense and was probably able to carry out some function as a communication facilitator (Myhrvold and Currie, "Supersonic Sauropods? Tail Dynamics in the Diplodocids," 1997).

Literary Popularity

Megalosaurus has not made much of a splash in the film world, though notable exceptions such as the television show Dinosaurs from the early 1990's do exist; anyone that has watched it knows that the show reminds us often through the voice of the father of the dinosaur family that Earl Sinclair is indeed "the mighty Megalosaurus." Aside from this show, though, few other shows exist which have shown Megalosaurus, the Dinosaur King cartoon being the only other show that I have definite knowledge of showing Megalosaurus at least once if not in America than at the very least in Japan. Megalosaurus actually appears prominently in literature more than it has on film. In the 1984 novel Carnosaur one of the main dinosaurs that is unleashed upon the world, in a genetic experiment gone awry a good six years before Jurassic Park was written, is a Megalosaurus. The author, John Brosnan, apparently holds little ill feelings toward the hit that Jurassic Park became though his novel came before and was quite similar. Today he gets the limelight though, because his novel featured a Megalosaurus where the other never even mentioned the dinosaur. Another novel which mentions Megalosaurus is actually almost 200 years old now. Between 1852 and 1853 Charles Dickens published a novel in series entitled Bleak House which featured the opening lines

Implacable November weather. As much mud in the streets as if the waters had but newly retired from the face of the earth, and it would not be wonderful to meet a Megalosaurus, forty feet long or so, waddling like an elephantine lizard up Holborn Hill.

Dickens was a master of the English language (and between the ages of 16 and 18 one of my greatest enemies though I will swear to the fact that my writing and speaking is much better for having to suffer through reading so many Victorian novels in high school) and his inclusion of a newly popular dinosaur in a Victorian novel is almost comical, but given the scientific and popular view of dinosaurs at the time it was written, this description of the weather is very powerful and, since it is mostly lost on us now that we have a different view of dinosaurs, is not distinctly understood to mean swampy and mucky like it did back when it was written. Still, well written and a good use of our poor old characterization of Megalosaurus.

References
Dickens, Charles, Bleak House, Project Gutenberg eBooks, http://www.gutenberg.org/files/1023/1023-h/1023-h.htm 2012

Interesting Things About Megalosaurus

We could spend all day on interesting points in the evolution of Megalosaurus from mistaken quadrupedal dragon like reptile to hulking Middle Jurassic theropod. The original name for a femur of Megalosaurus that was found was Scrotum humanum simply because the lower end of the femur, which was all that was found, look like human genitalia; I think some anatomists of the late 18th and early 19th century were sometimes, while being great minds, terrible perverts. Thankfully in the 1990's when a case was made to have this scientific name erased it was decided by the ICZN, the community that approves and disagrees with scientific naming, when the secretary of the committee decided that the name was a label for an illustration and not a binding scientific name. Imagine if it had stuck and taken precedence over Megalosaurus; that would be one dinosaur we could not discuss in public education ever.

The most unfortunate thing about Megalosaurus is that nearly 200 years later there have still been absolutely no complete skeletons of this dinosaur recovered from the European soils in which its fragments have been found. The fragmentation of the dinosaur has been a problem in the past, leading to the creation of many new species since named dubious or reassigned into other animal's genera. Melting pot that it once was, Megalosaurus is slowly being sorted out and has, generally, been cleaned of most dubious material by now. Until the day we have a complete skeleton, of course, having a complete picture of Megalosaurus is almost impossible and we may never, if we do not unearth a complete skeleton, even know what it actually looked like. Paleoartists do a good job filling in the gaps for now however.

©Alexander Lovegrove

History Lives!

Rarely do I find description papers older than the 1970's online to share with the voracious readers of this page.Today I am exceedingly pleased to share not one, but two 19th century papers written about Megalosaurus. The fist paper to be shared today is a copy of the original paper by Reverend William Buckland addressed to the Geological Society and dated February 20th, 1824. In this paper Buckland asked for the society to hear his arguments and description of a new genus and species of prehistoric animal and to aid in disseminating the information to the public that they might learn about this newly discovered animal. He describes the lower jaw fragment and teeth held therein but then also goes on, which I did not mention previously, to describe ribs, partial pelvic elements, vertebrae, and appendicular elements that have been assembled from many individuals and a few localities. Some of these parts have been re-examined over the years, but in this instance they are all used to describe Megalosaurus, whether they have been reassigned since I do not personally know.

The second paper is from the famous Joseph Leidy and is dated 1868 in volume 20 of the Proceedings of the Academy of Natural Sciences of Philadelphia. Leidy writes in his paper a newer description of a fragmented jawbone different from the one described by Buckland, and adds his own commentary on the shape of the jaw, head, and overall animal. Leidy's jaw fragment was housed in the Academy's museum. He goes on to describe relationships other animals may prove to have relating to Megalosaurus, some of which we know for a fact are not correct now. Eventually Leidy trails off onto other dinosaurs including a hadrosaur, but not after describing the supposed Megalosaurus jaw fragment in detail.

The final papers are a new set of descriptions of another species of Megalosaurus. Today only Megalosaurus bucklandii is recognized as a species, but at one point in the not too distant past there were at least five species partially or at least trivially recognized until either further evidence or re-examination of the remains reassigned those other species one way or another. Michael Waldman's 1974 description is of an animal he called Megalosaurus hesperis was actually redescribed as recently as 2008 and, in holding with the norm of reassigning Megalosaurus remains, Roger Benson renamed Waldman's Megalosaurus as Duriavenator hesperis.

Movie Time

Megalosaurus has been on camera many times, though not as many as Tyrannosaurus Rex and some more popular and better understood theropods. National Geographic did a short piece on Megalosaurus, focusing mainly on how paleontologists once interpreted dinosaurs through looking at the original illustration and reconstructions of what was thought to be the Megalosaurus body.



Megalosaurus was not as large as Tyrannosaurus though, and has since lost major starring roles in many movies including the original King Kong and even the movie Carnosaur, which is based off of a book of the same name where the main "monster" character was actually Megalosaurus. Carnosaur, by the way, is a ridiculously funny movie, though it is trying to be serious and it is not the author or the movie maker's faults really. That movie just had the unfortunate destiny of coming out after Jurassic Park even though the book was written before Jurassic Park the book. Anyway, getting back to Megalosaurus, its biggest starring role to date was on a Jim Henson Productions show which began airing in 1991 and was one of the best sitcoms ever with no human beings on screen (or is it the only sitcom ever with no human beings on screen?).

Megalosaurs Is Well Known with Children

I said yesterday that any generic bag of plastic dinosaurs usually holds a dinosaur that could certainly be Megalosaurus. That is certainly true. Additionally, there have always been toy dinosaurs that are labeled specifically as Megalosaurus. Typically they have been tail dragging green dinosaurs vaguely reminiscent of Godzilla with short stubby heads full of triangle teeth, but they have become slightly more modernized with the changing view of dinosaurs over the years. Thankfully, however, kids today do not have to rely on just their toys to learn about their dinosaurs. They have internet resources like KidsDinos and Enchanted Learning (complete with a not as awful as usual illustration of Megalosaurus that can be colored) and even Science for Kids has entries on Megalosaurus. Kids can sit down and play or watch Dinosaur King today and potentially see or use their Megalosaurus cards, of which there are three versions. Dinosaur Train, oddly, has not been inclined to add an episode with Megalosaurus. Given that it was the first described dinosaur it is quite odd indeed that the show has not approached the subject. Regardless, there is an awful lot to do today with the children in your life on this Labor Day weekend, if you are in the U.S., or just on this Sunday if you are not.

Mighty Megalosaurus

Megalosaurus at the Crystal Palace

Nothing says "19th Century Paleontology" quite like the statues at the Crystal Palace in London; except that giant Iguanodon that hosted a dinner party. The Megalosaurus to your left, yes, that is a Megalosaurus, is a product of that 19th Century paleontological thought. Strangely, the arms of Megalosaurus were never even close to large enough to constitute a quadrupedal stance, let alone be anywhere near as beefy as the arms on the Crystal Palace's statue. At least Megalosaurus did not have the displeasure of having its thumb put on its nose like Iguanodon did. The fact that Cuvier and other early anatomists thought of these newly found skeletons as giant reptiles, which we of course know that they are but not in the traditionally though of sense, completely influenced the sculptors of the Crystal Palace denizens; Megalosaurus just happens to be a prime example of that view point. In our current understanding this statue is horrendously inaccurate, but when you think back to what was known of dinosaurs at the time, before they were even widely called dinosaurs, it is in fact a very good piece of scientific art.

©Nobu Tamura

Megalosaurus, like many other dinosaurs, has come a long way since 1853 though. Today we know that Megalosaurus, in addition to still sounding like a pretty awesome dinosaur, was a large Mid-Jurassic theropod with three fingers on its noticeably shorter-than-a-leg arms and three forward pointing toes on its hind legs. It is very notable that the fifth digit on the foot is depicted as pointing backward, like dewclaws in modern canines. Given that much of the material attributed to Megalosaurus is fragmentary and incomplete, this has been adopted in conjunction with the fragmentary evidence and presumed characteristics; citations to academic papers supporting this information are not available at this time to myself and we know that does not mean they are not out there.

©Sergey Krasovskiy

 Megalosaurus has, however, fallen into that category of "typical" theropods. Every bag of dinosaur toys has a Tyrannosaurus with two fingers and a non-descript three fingered theropod that may be Megalosaurus or Allosaurus or somebody else. Regardless of that fact, Megalosaurus is a very interesting dinosaur in part because its classification and remains are still debated almost 200 years after their discovery and description. Granted, part of the reason is the fragmentary remains; the holotype is an incomplete right dentary (lower jaw) bone that contains a few teeth and is broken off at the attachments to the angular and surangular. While this Megalosaurus has that "typical" look, it also looks rather dangerous and hungry. There is a lot of personality in Megalosaurus, it just takes a little imagination to put those fragments together and give it that personality and from the 1853 statue to modern illustrations, Megalosaurus has always had some attitude and personality.