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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).
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.
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.
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.
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.
Here’s a drawing that I did a while ago, but for some reason, my computer screwed it up. It’s only recently that I’ve rescanned it and fixed it up.
Camarasaurus was the most common sauropod dinosaur within the Morrison Formation of western North America during the late Jurassic Period. Other species like Apatosaurus and Diplodocus might be more familiar to the ear, but in terms of the sheer numbers of specimens that have been found, this big guy tops the list. As far as size goes, it was a tad on the small side for a sauropod, measuring only 60 feet long. Its relatively small size (that is, compared with the other larger sauropods that it shared its habitat with) and meaty build likely made it one of the preferred targets for a mob of Allosaurus to take down. The reason why Camarasaurus was the most common species of its kind might be due partly to its smaller-than-average size (smaller stomachs mean more food to go around for everyone, and by extent leads to having larger populations) and partly to its apparently generalistic diet. Creatures which have a specialized diet are often hit hard when catastrophies arise, whereas dinosaurs that are more adaptable and flexible in terms of what they eat come out more favorably.
Many times, you’ll see these dinosaurs illustrated Gregory Paul-style, with thin spindly legs. I decided that the biomechanics of this simply weren’t feasible, and so I gave my animal suitably thicker more elephant-like legs, able to hold up the tens of tons of weight. Also notice that, contrary to other artistic renderings of this species, the neck is NOT held straight vertically upright, but is thrust more fowards in a 45 degree S-shaped curve. This is also one of the few dinosaur drawings that I’ve done in color. In terms of the color pattern, I’ve always imagined Camarasaurus colored in the scheme that you see above, even as a little kid – tan body with broad brown stripes and a somewhat yellowish-tan underbelly. I simply cannot imagine this species colored in any other way.
Keep your pencils sharp, people.
Today, I learned some very heart-breaking news. Stephen Czerkas, one of the true greats of paleo-art, recently died. He was 63 years old. The cause of death was liver cancer.
Czerkas was famous for his life-sized dinosaur sculptures, and he developed a very distinctive style – you could immediately recognize a Czerkas sculpture. His horned Allosaurus graced many children’s dinosaur books and TV shows, and his life-sized Carnotaurus was truly epic. However, his most famous work was his pack of Deinonychus raptors. Czerkas was one of the first paleo-artists to have his theropods adorned with feathers, and he also discovered that at least some species of sauropods had spines on their backs, which was incorporated into the BBC series Walking with Dinosaurs.
To all of those dino-lovers of my generation – those who came of age during the 1990s – Stephen Czerkas’ work would have been an integral part of your life. Czerkas was one of THE paleo-artists of the late 1980s and early 1990s, the time when I was becoming exposed to dinosaurs and other prehistoric life. The sheer awesomeness of his work influenced me profoundly both as an artist and as a person who dedicated his life to studying the past.
The paleontological and artistic spheres have lost one of the true greats of their domain, but his work will last and I dare say will continue to influence artists, scientists, and children generations from now.
RIP Stephen Andrew Czerkas (1951-2015) 😦
Hot off the presses! A new carnivorous dinosaur from Portugal has been officially named – Torvosaurus gurneyi.
The fact that Torvosaurus came from Portugal isn’t a revelation – it was, after all, featured prominently in an episode of the Discovery Channel mini-series Dinosaur Revolution (which I didn’t particularly care for). For years, people have known that there have been megalosaurid dinosaur fossils from Portugal, specifically the Lourinha Formation, which dates to the late Jurassic Period, about 150 million years ago. These fossils were tentatively ascribed to the species Torvosaurus tanneri, known from the Morrison Formation of the USA. However, upon closer examination, there are a few minor differences in the bone structure, so the Portuguese specimens were named Torvosaurus gurneyi, named after the famous paleo-artist James Gurney.
Torvosaurus was one of the last megalosaurid theropods, as they were being replaced by the allosaurids and the coelurosaurids. Torvosaurus and its kind ruled Europe durring the middle and late Jurassic Period. It measured 30-35 feet long, giving Allosaurus a serious run for its money, and possibly weighed somewhere in the realm of four to five tons.
As if this wasn’t news enough, there are some dinosaur embryos from Portugal which might belong to Torvosaurus as well.
For more info, check out the websites listed below:
- SciNews.com. “Torvosaurus gurneyi: New Giant Dinosaur Discovered in Portugal” (March 6, 2014). http://www.sci-news.com/paleontology/science-torvosaurus-gurneyi-giant-dinosaur-portugal-01794.html
- National Geographic Daily News. “Largest Predatory Dinosaur in Europe Found, Was ‘Big Bruiser'”, by Christine Dell’Amore (March 5, 2014). http://news.nationalgeographic.com/news/2014/03/140305-dinosaurs-biggest-europe-torvosaurus-gurneyi-animals-science/
- Nature. “Filling the gaps of dinosaur eggshell phylogeny: Late Jurassic theropod clutch with embryos from Portugal”, by Ricardo Araújo et al (May 30, 2013). http://www.nature.com/srep/2013/130530/srep01924/full/srep01924.html
Recently, I have decided that my Allosaurus color drawing, which I have re-tooled about four or five times and felt so proud of, actually needs to be re-tooled again. I had made that drawing the center focus of one of my blog posts some time ago. Here it is again if you don’t remember it.
One thing that immediately jumps out at me is that the tail is too narrow – there’s just not enough meat on it. I’ve noticed that many paleo-artists who follow what I like to call the “Gregory Paul School” of paleo-art often have their paleo-critters very shrink-wrapped, especially the tails. The tail’s weight needs to be proportionate to the weight of the front half of the animal; a tail that is not thick enough will make the animal front-heavy, and I can safely say that this Allosaurus looks front-heavy.
The second thing that I have a problem with are the lacrimal horns. Those are the rounded projections on the skull just in front of the eyes. Many times, I have seen paleo-artists put these very large or at least prominent fin-like crests on Allosaurus skulls. I have always been loathe to do this, since I am a stickler for anatomical correctness. If there aren’t any crests, I don’t put them on. However, when I was volunteering at the American Museum of Natural History (or AMNH as it is commonly abbreviated), I took various photographs of the two Allosaurus skeletons that they have on public display. Based upon this information, I knew that I needed to redo my drawing. I have decided to include the photographs here for any future reference for any aspiring paleontologist or paleo-artist.
Here is that dynamic running Allosaurus that everyone sees when they come into the entrance hall. I want to to take note of several things. First, look at that beautifully curved neck. Second, look how large the arms are in proportion to the body. Third, look at that enormous Baryonyx-esque thumb claw on each hand. Fourth, notice that the body is a lot more rounded than many artists often show, who make the body appear narrower and flatter.
Here is a close-up of the entrance hall Allosaurus‘ skull. I’m sorry if the picture looks a little fuzzy – I think I jerked the camera when I took the shot. Take note of a couple of things. First, notice that the jaws are strongly U-shaped. Second, the face is pretty much flat on both sides. This animal had absolutely no stereoscopic vision. Third, there does not seem to be any real three-dimensionality to the face – not a whole lot of wrinkles, ridges, and bumps, but almost flat.
I had a lot of trouble finding pictures of Allosaurus hands and arms for my drawing. So here’s one, so that you can get your proportions just right.
Now we move into the Hall of Saurischian Dinosaurs, located on the fourth floor. This is the room that is always the most crowded, aside from the entrance hall, because here is where the Tyrannosaurus skeleton is located, and seemingly every elementary school child in all of NYC wants to see it. This is the skeleton of Allosaurus seen in that hall. You might recognize the pose as being similar to a Charles Knight painting, which has been endlessly copied ever since. The two Allosaurus skeletons in the AMNH are meant to represent two modes of behavior: predator and scavenger. There are two things that I notice right away. First, it’s brown not gray – a rather superficial difference. But what jumps out at me is that the skull is a slightly different shape. The skull used on the skeleton in the entrance hall has an almost flat jawline, producing a rectangular-looking skull – this is the skull that is most commonly seen in museums and in dinosaur anatomy books. However, the skull that you see here has a more curvaceous S-shaped jawline, and the skull itself appears to be fatter and more robust than the one mounted on the entrance hall specimen.
Here is another view of the skull (again, sorry if it’s a bit blurry; I really need to work on not jerking the camera).
Here are some various views of that same skull from different perspectives. I took these shots because just having a side view doesn’t really tell me a whole lot of information. Again, you will notice that the skull is flat-faced with no stereoscopic vission. The only way that Allosaurus could see what was directly in front of it was if it cocked its head to the side like a bird so that one of its eyes could see something. Also, look closely at the rounded lacrimal horns. Notice those linear grooves running along the surface. That means that these horns were covered with keratin, the same stuff that your fingernails are made out of. Also, notice that the lacrimal horns are pretty-much in line with the post-orbital bones (the bones behind the eye socket). This would infer that the horns were not as pronounced as I had shown in my drawing.
Lastly, here is another photo of Allosaurus arms. Look at the size of those thumb-claws!