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During the 1940s, the front half of a fossilized skull was discovered in China. It was named and described as Lukousaurus yini in 1948. Lukousaurus lived during the early Jurassic Period, approximately 195 million years ago (MYA). Based upon the size of its remains, which consist only of the front half of its skull, it may have been six to eight feet long.
Some may cite Lukousaurus for it’s old age, but what grabbed my attention was when I read that the teeth had serrations only on the back edge. I have been told that this is a feature that is only found in the carnivorous dinosaurs commonly called “raptors”, more properly known as Deinonychosauria. This clade is divided into two families: Dromaeosauridae and Troodontidae. All dromaeosaurids have teeth which are serrated only along the posterior (back) edge, and some troodontids have this feature as well.
Although all raptor dinosaurs are found during the Cretaceous Period, paleontologists have hypothesized for years, based upon phylogenic analysis, that the ancestor of the raptors appeared millions of years earlier during the Jurassic Period. It may well be that Lukousaurus is that ancestor. Could it be that Lukousaurus is the oldest-known “raptor”?
Evidence to back up this claim is a bit thin. For starters, we’re not even sure if Lukousaurus was a dinosaur; it’s been proposed that it might, in fact, be a crocodilian. But let’s assume for the time being that it is a dinosaur. Is there any evidence which suggests that Lukousaurus might be a member of Deinonychosauria, or perhaps a close relative?
The first piece of evidence to support the hypothesis that Lukousaurus is a very primitive raptor is its age. Paleontologists have speculated that raptors appeared during the Jurassic Period, specifically either the early or middle Jurassic. The reason why is because birds are believed to have been descended from raptors, and the oldest-known birds come from the late Jurassic – therefore, raptors must have appeared a little earlier. Lukousaurus comes from the early Jurassic.
The second bit of evidence is geographic location. Raptors are believed to have originated in Asia and then spread elsewhere. Lukousaurus comes from China, specifically the Lower Lufeng Formation in Yunnan Province, China. It would have shared the landscape with the prosauropods Gyposaurus, Lufengosaurus, and Yunnanosaurus. it would have also lived alongside the early carnosaur Sinosaurus and the ornithischian Tatisaurus (we’re not sure if it was an ornithopod or an early thyreophoran; it might have looked similar to Scutellosaurus).
The third piece of evidence, which I have already mentioned before, is tooth structure. Lukousaurus’ teeth are very thin and blade-like, and are sharply recurved backwards. What is especially noteworthy is that the teeth have serrations only on the posterior edge – a feature found only in raptors.
This brings about the fourth piece of evidence, although this is subject to intense debate – taxonomy. It has been hypothesized that Lukousaurus was a coelurosaur, and the coelurosaurs were the ancestors of Maniraptora. This clade includes the ornithomimids, the therizinosaurs, the oviraptorosaurs, and the raptors. However, due to the incredibly fragmentary nature of Lukousaurus – it is, after all, known only from one fragmentary snout – its phylogenic position is uncertain. Yes, it has been classified as a coelurosaur, but it has also been classified as a ceratosaur, and even as a crocodilian. So, using taxonomy as evidence is incorrect; it’s more likely an opinion rather than evidence.
Lukousaurus might be an early raptor, but personally, I think it is an advanced coelurosaur which shows the beginning of raptor-like traits. This would make Lukousaurus a borderline coelurosaur-maniraptoran. Until more material from this particular species is uncovered, any assertions made as to which clade this creature belongs to will always be tinged with uncertainty.
Below is a drawing of the partial skull made by Tracy Ford.
- Lessem, Don; Glut, Donald F. The Dinosaur Society Dinosaur Encyclopedia. New York: Random House, Inc., 1993.
- Padian, Kevin, ed. The Beginning of the Age of Dinosaurs: Faunal Change Across the Triassic-Jurassic Boundary. Cambridge: Cambridge University Press, 1988.
- The Theropod Database. “Lukousaurus in Nesbitt’s matrix”, by Mickey Mortimer (May 7, 2011). http://theropoddatabase.blogspot.com/2011/05/lukousaurus-in-nesbitts-matrix.html. Accessed on December 24, 2013.
- Dinosaur Mailing List. “What is Lukousaurus?”, by Mickey Mortimer (September 4, 2000). http://dml.cmnh.org/2000Sep/msg00086.html. Accessed on December 24, 2013.
- The Bite Stuff. “Troodontid Teeth – WP#6”, by Jaime A. Headden (June 6, 2010). http://qilong.wordpress.com/2010/06/06/weekly-picture-6-troodontid-teeth/. Accessed on December 24, 2013.
Now that the manuscript for my history book on the ancient history of the Balkans is finished, I have some time to work on my art, which I have been neglecting for months. A while back, I wrote a post saying that I had a “to-do list” of various subjects that I wanted to address either in artwork or articles based upon items that have appeared in your searches of my website, but that was some time ago, and a lot has changed since then. Even so, I have kept this list in my mind, and I have been working on tackling the various items on it. Projects that I’ve completed so far are Alamosaurus, Ornithomimus, a Jurassic pliosaur, and – my latest post – Caenagnathus (which might be the same animal as Chirostenotes).
Now it’s time to move on to other things. A lot of you have been looking for stuff related to Dakotaraptor. Alright, that’s my next project, and I’ve already started work on it. Hopefully, it will be finished by the end of the month. It’s still very much in the pre-production research phase.
But what about what comes afterwards? Well, I’ve got several projects lined up. Here is a “top ten” schedule of what I’ll be doing, based upon what you have been looking for:
- Dakotaraptor (work has already begun on this).
- Allosaurus head (6 searches).
- Re-doing my full-body Allosaurus drawing, for the sixth time (a LOT of you have been looking for Allosaurus-related stuff on this website; 81 searches).
- Re-doing my Troodon drawing. The drawing that I posted to this website years ago is pathetically inaccurate, and needs to be re-done. (53 searches).
- Velociraptor (23 searches).
- Prehistoric sharks (10 searches).
- Prehistoric fish (7 searches).
- Carnotaurus. This guy’s one of my personal favorites, and I’m really looking forward to doing a full-body rendition of him (7 searches).
- Mosasaur (7 searches).
- Pterosaur (7 searches).
During the early 1920s, Charles W. Gilmore, a paleontologist from the Smithsonian Institute in Washington, DC, was prospecting for fossils in Alberta, Canada. While on this trip, he would discover several new species of dinosaurs, including a strange creature known only from a pair of incomplete hands. These hands had long slender fingers, which was highly unusual for theropods known at the time. He officially named and described them as Chirostenotes pergracilis in 1924.
Chirostenotes was originally believed to be a member of the family Elmisauridae. This is an enigmatic group of dinosaurs, whose members consist of only one genus, Elmisaurus. This animal lived in Mongolia during the late Cretaceous Period about 80 MYA, and the only evidence that we have of its existence is one incomplete foot and a hand found in 1970. Scientists recognized that the hands of Chirostenotes and Elmisaurus looked similar, and so Chirostenotes was placed into that family. By 1990, Elmisauridae was recognized as an invalid family name, and it was discarded.
Chirostenotes is now classified as a member of the family Caenagnathidae, named after the genus Caenagnathus, which might actually be the same animal as Chirostenotes (as early as 1990, scientists suspected that these two might actually be the same animal). The canaegnathids were a group of bird-like theropod dinosaurs who belonged to a much larger group called the oviraptorosaurs, who are well-known from Asia. Their presence in North America only adds further proof to a faunal exchange between Asia and North America. Caenagnathids are distinguished from oviraptorids by their feet, which look more like those of the ornithomimids, more commonly-known as “ostrich dinosaurs”. This suggests that the oviraptorosaurs evolved from the ornithomimids. According to current phylogenic analysis, the ornithomimids are more primitive than the oviraptorosaurs, so this hypothesis might be plausible.
Because Caenagnathus and Chirostenotes are known from incomplete specimens, nobody can make up their minds as to whether or not they’re two separate genera or if they’re the same animal. Some paleontologists firmly believe the former, while others firmly believe the latter. Because of their incompleteness, we are also not 100% sure what the animal looked like. It’s reasonably certain that it bore a strong resemblance to Oviraptor, Citipati, or Anzu, but any recreation of what the entire animal looked like is guesswork. During the 80s and 90s, there were a wide range of images crafted by various paleoartists which took a stab at what the whole animal would look like if it were fleshed out. Ever since the discovery of Anzu, which is both the largest and most well-known caenagnathid, the diversity of images has largely disappeared. Now, modern depictions of both Caenagnathus and Chirostenotes, if you can find them, are really nothing more than clone copies of Anzu, which I disagree with not only as a paleontology buff, but also as an artist.
Below is my own rendition of what I think Caenagnathus, or possibly Chirostenotes, or both, would have looked like. Since no complete skull of either species has been found, the design for the head is based upon a hypothetical skull drawing made by Tracy Ford. My drawing was made on printer paper with No. 2 pencil, Crayola and Prismacolor colored pencils, and a black felt-tiped marker. Since my scanner has a tendency to wash out a lot of the detailing, I had to do a bit of touching-up on my computer to replicate how the image looks in real life. Hope you enjoy, and keep your pencils sharp.
Hello all. I’ve recently finished an important writing project that I’ve been laboring upon for months. Now that it’s finished, I have a little breathing room to do art, and this is what I’ve done so far. I decided to do an updated version of an old illustration that I had made of an Ornithomimus. While the general color scheme was what I had in mind, I was never truly happy with the end-product. This latest version is much more in line with what I was imagining the “Bird Mimic” would look like.
Here is the “before” picture, made in 2013.
And here is the “after”, made today.
You’ll notice several differences right away, the most noteable of them being the re-shaping of its wing feathers. While Ornithomimus, or perhaps ornithomimids in general, had pennaceous feathers, I don’t think that they had primaries, because those would have been attached onto the wrist and the hand. This would have been difficult for ornithomimids because, unlike “raptor” dinosaurs (dromaeosaurids and troodontids), ornithomimids could not flex their hands backwards. I also increased the size of its tail feathers, made the neck thicker, changed the shape of the skull so that it was more anatomically accurate, and added Secretary Bird-style feathers to the back of its head. So much for form. In terms of color, I made it more vibrant, with deeper richer yellows and oranges and a lot more black patches. I changed the color of its bare skin from pink to a mixture of tan and black. I made its beak black, I changed its eye from yellow to blood red, and gave it black feet.
I can definitely see this character rushing about on the plains of the Hell Creek Formation. This shows that artists should never be stagnant. They must always strive to improve their work, and in so doing, improve their skill.
This drawing was made on computer printer paper with a No. 2 pencil, Prismacolor colored pencils, markers, and a black felt-tiped pen. The size of the drawing, from the tip of its nose to the tip of its tail feathers, measures 10.75 inches long, which is almost 1/12 scale, as the real animal possibly measured 12 feet long with its neck and tail fully stretched out.
Keep your pencils sharp.
The image of Nature “red in tooth and claw” is a compelling vision which appeals to the popular imagination. Time and again, paleo-art illustrations depict dinosaurs and other prehistoric animals actively engaged in fighting, hunting, and killing. It’s a well-known fact that violence sells, and it’s also a well-known fact that the animal kingdom can sometimes be very brutal. But was the Mesozoic world really a landscape of perpetual violence and bloodshed with animals constantly engaged in the savage business of survival?
Most naturalists, biologists, and animal behaviorists today would say “probably not”. Animals do not engage in a perpetual brawl-fest with each other. Even so, animals do have violent interactions, not only among different species (inter-species combat), but also within the same species (intra-species combat). The dinosaurs were no exception to this, and we have many pieces of evidence that individuals within certain dinosaur species engaged in violent behavior towards each other.
Before I get into the particulars of the paleontological evidence, it’s important to establish some ground rules as to the sort of intra-species combat that animals engage in today, and what the dinosaurs likely engaged in during the past. Physical combat between individuals or at least physical harm inflicted by one individual upon another is typically rooted in either social or environmental causes. Animals hurt each other for a variety of reasons, but seldom is it done purely for the hell of it – only people do that. Social reasons for intra-species combat include violence associated with mating and with mate selection. Bighorn sheep rival males cranially collide with each other until one contestant or another gives up. Other individuals within numerous animal species fight each other in order to assert their right to mate. Mating-based violence can also include some very rough love – some males within certain shark species will actually bite the females in order to assert their power over the female. Speaking of this, asserting dominance is also one of the main causes for intra-species violence, regardless of whether or not mating is involved. This involves dominance within a hierarchy system, such as a lion pride or a wolf pack. Other reasons for intra-species combat are environmental, and are usually tied to the availability of food and other resources. Territorial defense in a strong motivator in this behavior, and this is strongly tied to yet another reason, which is competition of food.
Now that we have established some of the motivating factors behind why modern animals hurt each other, let’s examine the sort of intra-species combat that dinosaurs would have engaged in. For instance, many animals will kick either out of aggression, self-defense, or purely to express annoyance. One dinosaur that possibly engaged in combative kicking was the late Cretaceous ornithopod Parksosaurus. This small speedy herbivore possessed unusually long scythe-like claws on its feet. One may hypothesize that Parksosaurus engaged in kicking contests like in cockfights, or like the modern-day Australian cassowary bird. Then again, Parksosaurus could have also used these long claws for better traction when running, like the cleats on a runner’s shoes, or could have used them like digging tools to scratch into the dirt to search for food or water.
Of course, when people imagine kicking dinosaurs, the first thing that likely pops into their minds are the “raptor” dinosaurs, such as Deinonychus, Velociraptor, and Troodon. Did raptor dinosaurs, with their killing claws, do the same? The large hook-shaped toe claws were certainly used for a specific function, either ripping prey open or pinning it to the ground. I can easily imagine two bird-like raptors squabbling with each other and kicking out with their feet, like a pair of roosters, but this is purely speculative as there is no hard evidence for raptors engaging in kicking each other.
Acheroraptor. © Jason R. Abdale. July 16, 2014.
Years ago, it was proposed that another meat-eater, the late Jurassic carnivore Ceratosaurus, could momentarily balance itself on its thick tail like a kangaroo and kick out. However, this idea has since been disproven. In order for this kicking behavior to work, the tail has to be very thick and muscular and at the same time be very flexible. Ceratosaurus’ tail was deep, but thin in cross-section, more like a crocodile’s tail than a kangaroo’s. Furthermore, it only had limited up-down flexibility. For the most part, the tail was held stiff for balance, and its range of flexibility was largely confined to side-to-side motion, not up-and-down.
Ceratosaurus. © Jason R. Abdale. April 23, 2012.
Ceratosaurus is famous for having a prominent horn on the end of its nose, hence its name. However, the horn was very thin and blade-like in form, and was certainly used for display rather than offensive action. However, there were dinosaurs and other animals in the past that likely used their heads as weapons. “Head-butting”, when animals engage in combat by using their heads as hammers, possibly occurred in earlier animals, such as the dinocephalians of the Permian Period. They had thick flattened skulls, and either pressed and shoved against one another or might have collided cranium against cranium. The dinosaurs which are most associated with head-butting are the marginocephalians, “the wide skulls”, the group that includes pachycephalosaurs and ceratopsians. At first glance, their skulls seem to have been specially designed for head-on physical combat. The eponymous Pachycephalosaurus had a rounded skull that was a solid foot thick, and many scientists have automatically assumed that such skulls were used in head-butting contests, like with modern-day bighorn sheep. A recent study by the University of Wisconsin has found that 20% of pachycephalosaur skulls exhibit head trauma, suggesting with some certainty that the pachycephalosaurs did indeed engage in head-butting behavior.
Pachycephalosaurus. © Jason R. Abdale. October 19, 2013.
But what about the other members of the marginocephalians? The ceratopsians, “the horned faces”, which include the likes of Triceratops and Styracosaurus, have also been assumed to have been highly combative animals, with their spikes, horns, and frills. In recent years, the idea of these horned behemoths duking it out with each other or impaling predators on their sharpened horns has come under intense criticism. Many of their frills are dominated by wide holes which served to lighten the weight but also made them practically useless for protection. Some scientists think that the frills and horns were primarily there for display and species recognition, and their use in defense was only an afterthought.
Chasmosaurus. © Jason R. Abdale. March 31, 2016.
As you’ve probably seen by now, most of the animals which have physical features that can be used in combat are herbivores. Why? Because they sometimes have to physically fight in order to stay alive and avoid being eaten by carnivores. Aside from teeth and claws, the meat-eating theropod dinosaurs don’t seem to have much in the way of special features that would be involved in fighting, not just eating. Ceratosaurus’ nasal horn was too thin and flimsy for attacking something, and so too were the eyebrow horns of its larger contemporary Allosaurus. However, another carnivore did possess eyebrow horns which very well might have been used in fighting – Carnotaurus, one of my personal favorites. Ever since its discovery in the 1970s, paleontologists and paleo-artists have imagined this dinosaurian toro engaged in head-butting clashes with other members of its kind. However, based upon the build of the skull, it seems more likely that it was engaged in cranial “shoving matches”, in which both competitors would press their skulls against one another (hence the Velcro-like arrangement of bumps and nodules on the top of their heads in between the horns) and proceed to push and shove in a demonstration of pure muscular strength until one side or another decided that their opponent was too strong, and retreated.
While predators might not necessarily have physically struck each other with their skulls, they could have used their heads in another way that is far more common among carnivorous animals of all sorts today – face-biting. Face-biting is a way to assert dominance among individuals, especially in communal or pack-hunting societies. Several modern carnivorous animals, such as lions, foxes, and wolves, engage in this behavior. The infamous creature known as “Jane”, who might be either a Nanotyrannus or a juvenile Tyrannosaurus (to this day, nobody is exactly sure), has evidence of face-biting. Since many animals today who engage in face biting do so in order to assert their position of dominance in a pack society, this could be further evidence that this animal was itself a pack hunter, at least as a juvenile. At least one specimen of a juvenile Daspletosaurus also has evidence of face-biting. Sue the T. rex possesses marks on the jaw which were previously thought to have been the result of bites, but were later proven to have actually been caused by a bone infection.
Predators aren’t the only animals today that engage in face-biting, so there may have been herbivorous dinosaurs that engaged in the same behavior. The most likely candidate for this is the small African herbivore Heterodontosaurus. The tusks on this creature could have been wielded in actual biting, or they could have been used for fang-bearing contests like modern baboons. Many animals bear their fangs or canines when aggressive, and Heterodontosaurus possibly did this to intimidate rivals and scare off predators. Another animal that can be compared with Heterodontosaurus is the musk deer. However, their long saber-like canine teeth are grown for display, not combat. Musk deer grow huge teeth instead of growing antlers in order to over-awe rival males and to impress females.
Another possibility for serious dinosaur fights was among the sauropods. With their massive builds, any hit, no matter how light, likely would have caused some kind of damage. One modern long-necked animal that uses its body in sheer brute force is the giraffe – a rather placid-looking animal, but don’t make it angry. During the mating season, male giraffe will proceed to whack each other, swinging their long stiffened necks around like baseball bats, with the short stumpy horns on the tops of their heads inflicting some serious pounds-per-square-inch. Some sauropods, like Apatosaurus, had very massive thick necks in proportion with their body size. This leads some to speculate that Apatosaurus and its ilk used their bruiser builds to inflict bruises on others.
But what about the opposite end of a sauropod? For many of them, the tail was just as long, or longer, than the neck. Tails can be effective weapons. Crocodilians and monitor lizards engage in tail whacking as a way to ward off threats. Many sauropods had thick tails, but others, like Diplodocus, have very long thin tails, and some believe that these long whip-like tails were indeed used like whips. A sharp crack across the side would make any Allosaurus wary. Of course, there are dinosaurs that almost certainly used their tails specifically for combat: the stegosaurs and the ankylosaurs. Evidence has been found for injuries inflicted by these animals upon predators, but I’m not certain if any evidence exists for stegosaur spikes or ankylosaur clubs being used upon members of their own kind. However, I can’t imagine it NOT happening.
Well, if you don’t have any biological weaponry on your side, like fangs, horns, spikes, clubs, or whatever, then raw physical force is your go-to option. There is evidence that predator species tangled with prey. The famous fossil find of a Velociraptor and a Protoceratops perpetually locked in a mutual mortal combat proves this. But this is likely an example of an attack-gone-wrong. Did dinosaurs of the same species physically grab onto and grapple with each other? Did dinosaurs wrestle, the way that some lizard species do today? Monitor lizards are a prime example of this, when two males will attack each other by essentially doing reptilian ju jitsu. Did dinosaurs wrestle? I’m not sure, but I’m leaning towards no, especially for the larger ones. Many small dinosaurs had thin delicate bones that could be easily broken, and many of the larger dinosaurs simply did not have the arm dexterity to do rough-and-tumble wrestling maneuvers the way that you see monitor lizards doing today. Furthermore, with their large size, being body-slammed to the ground would have done a lot of damage. As they say, the bigger they are, the harder they fall. Many dinosaurs show signs of physical trauma, including broken bones. Many led a very brutal life, with some skeletons being covered with injuries. For those reasons, I would say that most dinosaurs wanted to avoid intense physical combat.
Sometimes, the violence goes to its absolute extreme, and animals deliberately kill each other. Like intra-species fighting, intra-species killing has several motivating factors, both environmental and social. Animals kill each other to either reduce or totally eliminate competition over limited resources. Animals will also kill rivals to increase their own chances for mating, as well as killing the offspring of rivals to increase their own offspring’s chances for survival. As an example, new male lions that take over an existing pride will often kill all of the pride’s cubs in order to completely eliminate the legacy of the preceding male leader.
The most extreme form of intra-species combat is killing followed by cannibalism. Although it is largely taken for granted that prehistoric carnivorous animals ate their own kind under certain circumstances, there is little evidence to support this hypothesis. Some animals will kill and eat the young of other individuals in order to improve the chances of survival for their own young. Others may kill and eat their own kind out of starvation. Still others, like alligators, may view other members of their own kind as a legitimate food source, no different than any other prey item, and actively hunt, kill, and eat each other.
For a long time, it was believed with the firmest dogmatic conviction that the late Triassic dinosaur Coelophysis practiced cannibalism. However, this long-held belief has come into question upon closer examination of the famous Ghost Ranch specimens. It now appears that many of the bones which were previously believed to be inside the ribcages of others were actually lying underneath the ribcages. Furthermore, some of the bones previously identified as juvenile specimens have recently been re-identified as belonging to other reptile species. For the record, I am not stating that Coelophysis never engaged in cannibalism. I am stating that the evidence for cannibalism in this species is not as clear-cut as once believed and needs to be taken with a certain degree of doubt. If the study of paleontology has taught me anything, it’s that there is no such thing as dogma.
Coelophysis. © Jason R. Abdale. April 26, 2015.
Although there’s questionable evidence for cannibalism in Coelophysis, there is more compelling evidence in another dinosaur from the opposite end of the Mesozoic spectrum – Majungasaurus, an abelisaurid from Madagascar who lived at the very end of the Cretaceous Period. In 2007, scientists published findings that tooth marks discovered on some Majungasaurus bones matched the teeth in Majungasaurus’ jaws. So far, this is the only conclusive proof that a theropod species killed and/or ate the flesh of its own kind.
I would like to say one thing, though: just because there’s evidence that an animal was cannibalized, that doesn’t necessarily mean that this individual was killed by the animal feeding off of it. As said before, scavengers will sometimes eat the dead bodies of their own kind. To them, meat is meat, no matter where it comes from. Others will not usually eat their own kind, but will do it if they’re desperate enough and cannot find other sources of food. As an example, most humans who have engaged in cannibalism do it out of necessity, not out of habit.
Anyway, that’s my take on intra-species combat amongst dinosaurs. Hope you enjoyed it.
Greetings all. Every child with a rough grasp of what life was like in Late Jurassic North America probably knows the Morrison Formation’s main characters. If such a child were to be asked to name the meat-eaters from that formation, the name Ornitholestes would definitely pop up, likely somewhere around third or fourth place.
Ornitholestes was a 6-foot long coelurosaurid theropod dinosaur that lived in western North America during the late Jurassic Period, 155-145 MYA. It is commonly depicted scampering about in the forest, or along the edge or the forest, or sneakily hiding in the shadows out of sight of the larger predators. With the likes of Allosaurus and Torvosaurus stomping around, it’s easy to see why paleo-artists have relegated little Ornitholestes to a bit-part on the Jurassic stage.
But I like to think that Ornitholestes‘ part was much bigger in the never-ending drama of Mesozoic life. Let’s look at its body. I’ve already stated that it was 6 feet long and was therefore about 2 feet tall – large enough to bite you on the knee. It likely weighed a hundred pounds or a smidge less than that – certainly not more. Its skull is worth looking at. Contrary to what has been commonly portrayed, it DID NOT have a little Ceratosaurus-like crest on the end of its nose. That mistake was made when a dislocated bone was mis-identified as a nasal crest. The skull was thin and deep, like a battle axe, and based upon its structure and that of its neck, it likley had a very strong bite. The teeth are small, but they are rather thick in cross-section. A powerful bite and thick teeth? This makes Ornitholestes sound like a precursor to the tyrannosaurs, and no wonder, because the tyrannosaurs are, in fact, highly-evolved coelurosaurs – the same group that Ornitholestes belonged too. The eye sockets on this baby were huge, so it is likely that Ornitholestes was a nocturnal hunter. As for its body, it was a bit on the muscular stocky side, so it was physically strong. It was equipped with long arms ending in three hook-like claws on each hand, and it had a long tail. We can also be fairly sure that Ornitholestes had a coat of thin whispy fur-like feathers on its body since other coelurosaurids that were more primitive and more advanced that Ornitholestes had feathers.
So what can we determine? It was strong for its size, its jaws could crack through eggshells and small bones, it could run, and it could grapple. In short, Ornitholestes was the hyena of the Jurassic savannah.
Hyenas are nothing to laugh at (I’m sorry, that was bad). Hyenas have a reputation for being scavengers, likely because they are commonly seen picking at the leftovers of the lions’ dinner, and because their jaws are the strongest jaws pound-for-pound of any meat-eating animal on the African plains – good for cracking hrough thick bones of carcasses. But in reality, hyenas are effective hunters as well. They are pack hunters, like lions or wolves, and it’s not unusual to see a gaggle of them, panting and bare-teethed, running down a zebra or a wildebeest.
Was Ornitholestes the same way? Unfortunately, fossils rarely provide evidence for animal behavior. The fact that Ornitholestes fossils are so rare doesn’t help matters. But I dare say that these carnivorous critters were a serious threat to dinosaur mothers who had eggs to protect, they likely did significant danage to hatchlings, they preyed upon smaller animals like thick-boned mammals, and asuredly were seen scavenging carcasses leftover by other larger meat-eating dinosaurs.
A while back, I drew a picture of Ornitholestes and posted it to this blog. However, it was an “old school” picture portraying Ornitholestes covered in scales. I have recently made an updated version, and I’m posting that image below.
In addition to the feathers, I’ve also slightly altered the shape of the skull to be a little more accurate. I always try to improve my work, and I dare say that a few years from now after my skills have improved further, I’ll make a drawing of this guy that’s even better than the one you see here.
Keep your pencils sharp, people.
A while back, I asked you, the reader, if you had any requests for articles and artwork that you would like me to do, but I received no reply. However, I recently looked at the search terms that come up on this blog’s administration page. Most of the terms concern subjects that I’ve already written about or illustrated, but there were a few others on subjects that I haven’t touched yet, or have only just alluded to. Terms which showed up frequently were (in order of frequency):
- Alamosaurus (12)
- Caenagnathus / Chirostenotes (9)
- Pterosaurs (8)
- Liopleurodon (7)
- Mosasaurs (6)
- Dakotaraptor (5)
- Velociraptor (in color) (5)
- Suchomimus (4)
- Carnotaurus (3)
- Oviraptor (3)
Others caught my interest as potential future art or writing projects, including:
- Allosaurus courting
- Allosaurus head
- Allosaurus walking
- Dinosaurs of Texas
- Dracorex head
- Iguanodon head
- Pachycephalosaurus keeping shelter
- Triceratops eating
- Tyrannosaurus juvenile
- Lacrimal horns on dinosaurs
- Mesozoic turtles
- What dinosaurs lived on Long Island?
The last three sound like interesting research projects. Anyway, based upon what I have seen, I think that I can gauge what you would like me to do. So, I’m treating these statistics pretty much like a to-do schedule. Right now, I’m really hammering on a super-detailed drawing of a full-body T. rex, which I hope to have finished within one or two weeks, and then put up here for you to admire and comment on. After that, I’ll focus on the items on these two lists – the “frequency list” will take priority. I’m happy to say that some of these terms are on things that I’ve had in the back of my mind for a while, so this will give me the impetus to do them. Take care everybody, and keep your pencils sharp.
Anzu was a caenagnathid from the Hell Creek Formation. I wrote of its discovery and naming in an earlier post that you can read here. The caenagnathids were a primitive group of oviraptorosaurs, the “egg thief” dinosaurs. Anzu is so far the largest species from this group found in North America, measuring 10-13 feet long from nose-tip to tail-tip, and it was also one of the last of its kind.
In terms of this picture, the chicken-like wattles are purely conjecture on my part, as are the types of feathers and color patterns.
In December 2013, scientists announced the discovery of a new raptor dinosaur from the Hell Creek Formation, which they named Acheroraptor. When news first came out about it, I wrote a post, which you can read here. Ever since I put it up, it has remained one of my most-viewed posts on this website. Accompanying the article, I included a drawing, which you can see below:
I very quickly hashed this drawing out, and to tell you the truth, I wasn’t at all pleased with it, despite the fact that the post got a heck of a lot of hits. It was an improvement (though not by much) of an earlier feathered raptor drawing that I had done: Troodon. Due to the rushed need to get a drawing out as quickly as possible, I didn’t spend a whole lot of time coming up with a unique color scheme. So, the color pattern on the above drawing and the Troodon drawing are almost identical. One feature that I included right away was a fluffy feathery ridge running down its back. The head is rather scary and menacing looking, and somewhat boxy – very Jurassic Park-ish. In retrospect, since Acheroraptor was a close relative of Velociraptor, its head probably didn’t look like this.
Today, I finished a revised and probably more accurate drawing of what Acheroraptor would have looked like. I kept the overall shape, but I changed the shape of the head and I put some more detail in the arm feathers. The most obvious change is the striking black-white color scheme, which I based upon the coloration of the Northern Goshawk. If this drawing was in color, I would have given my creature transparent glassy red eyes.
Making this drawing was a real pleasure, and I’m surprised that doing it didn’t take as long as I had expected – only five days. Please comment on my work and on the “before-after” transition. Keep your pencils sharp!
All I can say is “It’s about time!!!”
After sitting around for years without an official description, a bird-like dinosaur found in the Hell Creek Formation has finally been given a name. I’m very happy about that. What I’m not happy about is the name that was actually chosen – Anzu wyliei, a name that I REALLY don’t find appealing.
Last year, I read that a bird-like dinosaur more commonly found in the Gobi Desert was discovered in North America. Furthurmore, I found out that it was actually on display in Pittsburgh, and had been for several years – it shows just how horribly behind the times I am. However, I was aghast when I learned that this creature didn’t even have a name. I asked “What the hell’s been taking them (meaning the scientists) so long?” Well now the wait is over.
Anzu (I’m actually shuddering as I’m writing the name – I just loathe the way that it sounds) was a member of a family of dinosaurs called Caenagnathidae. The caenagnathids were a sub-group within a super-family of theropods known as the oviraptorosaurs, or “egg thief lizards”. These very bird-like dinosaurs are well-known from Asia, especially China and Mongolia, but they are almost unheard of anywhere else. Oviraptorosaurs ranged in size from five to twenty-five feet long, and might have evolved from the ornithomimids, the “bird mimics”, commonly known as “ostrich mimics” due to their ostrich-like appearance. The most famous of them was Oviraptor, “egg thief” found in Mongolia by the adventurous Roy Chapman Andrews. The name came from the discovery of a partial skeleton lying on top of a nest of eggs. Chapman and his colleagues thought that the animal was in the process of plundering the nest when it was killed. It wasn’t until later when the insides of the eggs were carefully examined that paleontologists discovered that the preserved embryos were that of other oviraptorosaurs. This animal wasn’t preying upon the eggs – it was the mother.
The caenagnathids have had a confusing history, dating back to the early 20th Century. In the early 1920s, the famous paleontologist Charles W. Gilmore was fossil hunting in Alberta, Canada, when he found the remains of a new and strange creature known only from a pair of incomplete hands. In 1924, he gave them the name Chirostenotes pergracilis. Another dinosaur was named based upon an incomplete foot, and it was called Macrophalangia. By the late 1970s, scientists realized that these two animals were the same, and Chirostenotes became the official name.
But what sort of creature was Chirostenotes? It was clearly a theropod – a bipedal meat-eater – but the bone structure was unlike any other theropod known. In fact, it looked very bird-like. It was believed that Chirostenotes was most similar to another mysterious dinosaur called Elmisaurus, which came from Mongolia during the late Cretaceous Period.
For a long time, Chirostenotes was the only North American oviraptorosaur, specifically a caenagnathid. It was found in rocks dated to the Campanian Stage (80-70 MYA) of the Cretaceous Period. Then, in the 1960s, another oviraptorosaur – and a very early primitive one at that – was found, named Microvenator, “the little hunter”. It lived in Montana approximately 100 million years ago alongside Deinonychus and Tenontosaurus. This showed that oviraptorosaurs were present in North America for much longer than previously suspected.
It had been believed for a while that Chirostenotes and its kind had become extinct a millions of years before the dinosaurs’ exinction. However, in the 1990s, fossils of an animal which might have been an oviraptorosaur were found in Montana in rocks that dated to the very end of the Cretaceous Period – the famous Hell Creek Formation, the home of Tyrannosaurus rex. No oviraptorosaur fossils had ever been found there before. In 1994, Canadian paleontologist Phil Currie, an expert on theropod dinosaurs, published a paper on a fragment of a lower jaw found at the “Sue” site. Based upon it’s shape, it was obviously an oviraptorosaur, specifically a member of the family Caenagnathidae. However, this specimen was significantly larger than any previously-known specimens. It could have been a larger specimen of Chirostenotes, or it might have been a new species.
The problem was that Chirostenotes was known only from a few fragmentary finds – a complete or nearly-complete skeleton had never been found. Then, a pair of incomplete skeletons were found in Hell Creek, and were described in 1995. Ever since then, they have been housed in the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. The staff at the Carnegie Museum even took these two skeletons, composited them together, and put the creature on display for the public! However, the creature still did not have a definitive identification. Paleontologists were uncertain as to whether “the Triebold specimens”, as they were called, were Chirostenotes or maybe another larger species.
In 2011, Matt Lamanna and other scientists announced that they were studying the Hell Creek oviraptorosaur in more detail. Based upon a preliminary view, they stated that it was very similar to Chirostenotes, but they shied away from going so far as to claim that it was a distinct species.
In 2013, a team from the Burpee Museum (the same museum famous for “Jane”, which might be either a Nanotyrannus or a juvenile T. rex, depending on who you ask) discovered the partial skeleton of a caenagnathid oviraptorosaur near the small town of Ekalaka, Montana. The bones were so large that they originally thought that they had found a T. rex; Professor Thomas Holtz of Maryland rushed to the site and confirmed the animal’s identity. This specimen was even larger than the Triebold specimens in the Carnegie Museum. It was affectionately nicknamed “Pearl”.
In 2014, Matt Lamanna and three other colleagues published a paper on the Triebold specimens collected from North and South Dakota. After an exhaustive analysis of the bones, they concluded that the Triebold specimens were not Chirostenotes or Caenagnathus, but constituted an entirely separate genus. They called it Anzu wyliei. According to Lamanna’s own report, the dinosaur was named after Anzu, a feathered bird-like demon from Mesopotamian mythology, and measured somewhere between ten to fifteen feet long.
What the heck does a Mesopotamian demon, feathered or otherwise, have to do with a North American dinosaur? I can understand if the fossils were found in Iraq, but they weren’t. I would actually be highly surprised if ANY dinosaur fossils were uncovered in Iraq. It would be a lot more fitting if it was given a traditional Greco-Latin name, something like Dakotaraptor, or maybe even named after a being from native Sioux Indian folklore, like Wakinyanoraptor (“Wakinyan” is the Sioux name for the thunderbird sky spirit).
But then again, what the heck does the white-skinned feathered serpent god from central Mexico have to do with an unusually large pterosaur from Texas, which neither looked anything remotely like a serpent, nor had feathers, nor came from Mexico? I’m talking about Quetzalcoatlus, for those of you who haven’t caught on. So I suppose I shouldn’t be too harsh. Still, Anzu … it just sounds SOOOOO wrong. Unfortunately, we’re all stuck with it.
The specimen uncovered by the team from the Burpee Museum is also likely a specimen of Anzu.
- “A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America”, by Matt Lamanna, et al (March 19, 2014). PLOS One, 9 (3): e92022. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0092022
- SciNews.com. “Anzu wyliei: New Bird-like Dinosaur Discovered”, by Enrico de Lazaro (March 19, 2014). http://www.sci-news.com/paleontology/science-anzu-wyliei-dinosaur-01811.html