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Lukousaurus: The first “raptor”?

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.

Sources:

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Caenagnathus, or Chirostenotes, or…um…something…

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.

 

Ornithomimus, Before and After

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.

Head-Butting, Face-Biting, and Tail-Whacking: Dinosaur Intra-Species Combat

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.

Ornitholestes with feathers

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.

ornitholestes-with-feathers

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.

Tyrannosaurus rex with scales

Tyrannosaurus full body with scales

Behold my masterpiece.

This is the fifth T. rex drawing that I’ve posted to this blog, and it is the hardest drawing that I have ever had to make. Every individual scale was done by hand, one by one. This drawing took me months to finish. To give you a better idea about the utterly insane amount of detail, the actual drawing of the dinosaur itself from the tip of its nose to the tip of its tail measures precisely 24 inches. Most of the drawn scales measure at only one millimeter in diameter.

As you can see, it is done in the same pose as my previous two full-body T. rex drawings, but I made some noteable improvements:

  1. Slightly changing the shape of the skull – my original one looked a little too much like Tarbosaurus rather than Tyrannosaurus.
  2. Not making the face as shrink-wrapped as the original head drawing was.
  3. Making the neck more detailed and fuller.
  4. Changing the position of the hands to be more anatomically correct.
  5. Making its body fatter – the original was too skinny.
  6. Making the tail thicker and fatter to properly counter-balance the now-heavier front half of the body.
  7. Changing the shape of the feet.

This drawing was made on several sheets of 8.5 x 11 printer paper, with just an ordinary No. 2 pencil…and a whole lot of patience.

Requests for articles and artwork

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:

  • Abelisaur
  • Allosaurus courting
  • Allosaurus head
  • Allosaurus walking
  • Australovenator
  • Deinonychus
  • Dinosaurs of Texas
  • Dracorex head
  • Elasmosaurus
  • Iguanodon head
  • Neovenator
  • Pachycephalosaurus keeping shelter
  • Styracosaurus
  • 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

Anzu

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.

Torvosaurus

Torvosaurus

Torvosaurus tanneri (“Nathan E. Tanner’s savage lizard”) was one of the largest theropod dinosaurs in the Morrison Formation. It measured 35 feet long, the same size as Allosaurus. However, Torvosaurus came from a more primitive line of theropods, the megalosaurs. As such, it retained some more primitive features compared to more advanced theropods living at that time like Allosaurus, and was probably less intelligent than Allosaurus (although not by much, apparently, since Allosaurus wasn’t exactly the brightest bulb either, according to studies of Allosaurus’ brain).

Torvosaurus and Allosaurus may have lived in the same location at the same time, but Allosaurus was clearly the most numerous theropod in the Morrison Formation. Very few remains of its competitor have been found. The first fossils of this animal were discovered in Colorado in 1971, and the species was officially named and described in 1979. Another species, T. gurneyi, was found in Portugal’s Lourinhã Formation, also dated to the late Jurassic. Although known from incomplete remains, it’s evident that the European species has a more boxy rectangular skull than its North American counterpart.

Torvosaurus and Allosaurus had the same length, but they possessed different physical proportions. These anatomical differences no doubt drove these two species to develop different hunting styles. It seems that Torvosaurus was a Jurassic analog for a tyrannosaur, since it had an unusually large head and unusually small arms in proportion to its body. Its body was long and shallow, whereas the body of Allosaurus was short and deep – good for a large heart and lungs, indicating an active lifestyle. Torvosaurus’ neck was short and muscular, while Allosaurus’ neck was longer and more sinuous. Torvosaurus had short arms and small hands (but unusually large thumb claws), while Allosaurus had longer arms, huge hands, and absolutely huge claws – obviously used for grabbing and ripping things. Torvosaurus seems to be rather front heavy (good for physically slamming it’s jaws onto prey) while the weight on Allosaurus appears to be more evenly distributed. Allosaurus also had an unusually long tail in proportion with its body – a definite feature of an agile runner. Therefore, it seems that Torvosaurus was primarily a short-distance chase ambush hunter who relied upon its jaws to do most of the work. By contrast, Allosaurus was a very active energetic predator who was capable of impressive speed and quick turns.

This drawing took a long time, as you can assume from its high amount of detail. Every individual scale was drawn one by one. To give you a better appreciation of the time to draw this, in real life this drawing frome nose-tip to tail-tip is only 21 inches long – 1/20 scale, as most of my prehistoric drawings are. Medium was No. 2 pencil on copy paper, along with some touch-up on my computer to fix the places where the two pieces of paper were joined together.

Keep your pencils sharp, everybody.

Dinosaur Day 2015 at the Garvies Point Museum

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Well, it was that time of year again! Every April or so, at around the time of Easter, the Garvies Point Museum and Preserve, located in Glen Cove, Nassau County, New York, holds it annual “Dinosaur Day”. This is one of the days that I really look foward to for a few reasons. First, I get to work at a place that I absolutely love and meet with some good friends. Secondly, I get to be out of NYC for a little while, which is something that I ALWAYS look foward to. Third, I get to talk about a subject that has fascinated me since my earliest days – paleontology.

Veronica, the museum’s de facto head of administration, did a wonderful job along with other members of the museum staff of setting up the classroom where the day’s major activities would be taking place. Recently, the museum’s library was substantially increased. The Sands Point Museum and Preserve had closed down its library a short while ago, and all of the books and papers were sent to the GPM. I should state, though, that almost all of these documents were originally part of the GPM collections anyway, and they just got them back, that’s all. However, Louis (one of the workers at the Garvies Point Museum, but works primarily at the Old Bethpage Village – another place that I really love) has been working hard to re-catalogue all of these books and papers back into the museum’s database.

The name of the event was somewhat misleading, as it concerned all prehistoric life, not just dinosaurs. We had exhibits on primitive mammal-like-reptiles, dinosaurs, and prehistoric mammals.

Here are some pictures of what the room looked like both during and after the hoards of kids showed up.

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Most of the really young children gravitated immediately towards the dino toy area and the fossil digsite. The older children and a lot of the adults were interested in the information that I and others were giving. They were especially interested in Dimetrodon, the famous sail-backed pelycosaur from the early Permian Period. I don’t think that I have ever had to say the name”Dimetrodon” so many times within the course of a single day! It seemed to be the only thing that many of them wanted to talk about!

Some of the major topics of interest on this day were: the Permian Mass Extinction, which occured about 251 million years ago, when an estimate 95% of all life was wiped out; of course, T. rex was a favorite; as too was Allosaurus, who competed with its larger relative for attention from the crowds. This was helped in no small part to the fact that we had a lot of Allosaurus “stuff” arrayed for them: a picture of the skull, a hand model, bone casts, a model, and my drawing which you might recognize from an earlier post on this blog.

Finally, here’s a picture of me, “the Dinosaur Man” as several members of the museum staff call me, dressed up as an amateur paleontologist. In addition to my olive drab Garvies Point Museum shirt, I also wore a khaki utility vest, because apparently ALL paleontologists wear khaki utility vests! I thought that wearing it would help to enhance my ethos with the audience, and by my reckoning, it worked.

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