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Triceratops was the last and largest of the ceratopsians, the “horn-faced” dinosaurs – other familiar members of this group include Chasmosaurus, Styracosaurus, and Protoceratops. Triceratops existed from about 70-65.5 MYA, and measured 30 feet long. There are currently two confirmed species: T. horridus and T. prorsus; the first one is the more famous and numerous of the two. They can be distiguished by their short nasal horns. Triceratops horridus has a short fat nasal horn, positioned a considerable way up the snout, and sticks more or less straight up, perpendicular to the line of the skull. Triceratops prorsus has a somewhat longer and thinner nasal horn, it is positioned more to the front of the nose, and it is angled forward.
There’s also been a dispute raging over the past few years as to whether or not another ceratopsian species named Torosaurus is actually another older age stage of Triceratops. This is really complicated, so I won’t even bother to get involved in this academic brawl. All I can say is that this subject appears to be just as hotly and intensely debated as the whole dispute regarding T. rex as a predator or scavenger.
The drawing which you see here is Triceratops horridus. One thing that you’ll notice is how large the head is in proportion with the rest of its body. This is not artistic license – the head really was that big! The second thing that you’ll notice is the lack of detail on the skull, showing instead a scarred but still mostly smooth surface. Paleontologists including Jack Horner and Peter Larson suspect that the top of Triceratops’ skull, including its distinctive neck frill, was covered in a layer of keratin, the same stuff that your fingernails are made of. This horny / keratinous covering might have been colored dark, as horn tends to be, or it might have been bright red due to the numerous blood vessels which are imbedded into the frill’s structure. Perhaps the males were brightly and vividly-colored, while the females were more drab and subdued.
Triceratops, regardless of which particular species, was a very populous animal. In the Hell Creek Formation, 60% of the dinosaur fossils found there belong to Triceratops.
I started drawing this picture months ago, but I got stalled with my classes and with the publication process of my book, and so I had to stick it on the shelf. These past few days, I’ve tackled it hard and completed it. I used my preferred medium, regular No.2 pencil.
Goodbye, and I hope that all of you had a good holiday.
A few days ago, scientists announced the discovery of a new species of dinosaur – Acheroraptor, “thief from Acheron”. I’m sorry to disappoint all of you Aliens fans, but no, this dinosaur is NOT named after Planet LV-426, code-named “Acheron”. The name actually refers to the Acheron River in ancient Greek mythology, “the River of Pain”. This name is an obvious pun on the name of the place where the fossils were discovered – the Hell Creek Formation in Montana.
Not much is known about this animal, but here are a few statistics. As you can probabaly guess, Acheroraptor is one of the “raptor” dinosaurs made famous by Jurassic Park. Raptors are divided up into two main groups: the dromaeosaurids and the troodontids. Acheroraptor was a dromaeosaurid, and this brings up another issue…
In an earlier post, I talked about Dromaeosaurus, a dromaeosaurid raptor from western North America. I had stated that its teeth had been found in several different locations, including the Hell Creek Formation. Well, that was perfectly true when I wrote it, but not anymore. For the past few decades, paleontologists had been finding raptor teeth in the HCF, and since they looked similar to the teeth of Dromaeosaurus, these teeth were ascribed to that genus. However, Dromaeosaurus was only known from Canada, and its fossils were found in rocks that were dated much older than the Hell Creek Formation – ten million years older, to be exact. But few other raptor dinosaurs were known from late Cretaceous western North America, and the teeth did look more or less similar to the teeth of Dromaeosaurus, and so that was the identification that was given. Now, paleontologists have discovered that all this time they were perpetuating a case of mistaken identity. It actually happens quite often in this particular science. It appears that the teeth which had been found in the HCF for decades actually belonged to this new species, not Dromaeosaurus.
Acheroraptor’s fossils were found in rocks dated to the extreme end of the Cretaceous Period, 65.5 million years ago, right when the dinosaurs became extinct. It therefore appears that Acheroraptor is the earliest-known raptor, geologically-speaking, being around right up the the point when the asteroid hit.
There are few fossils to go on, consisting of a partial maxilla, a partial dentary, and numerous isolated teeth. Based upon shape and size, paleontologists have determined that Acherorapror was a dromaeosaurid, rather closely related to Velociraptor, and have hypothesized that it may have reached ten feet long. Perhaps in the near future, more fossils will be uncovered which will give us a more complete picture of this animal.
And speaking of pictures, here’s my picture of Acheroraptor! – good segway, right? I further improved the wings from my old Troodon and Ornithomimus drawings, and I made the subject a little more three-dimensional. Rather than standing perfectly sideways, it’s positioned on an angle.
I drew the first sketch when I was giving my English students their final exam on Wednesday December 18, and then I polished off the final product when I got home. I had originally intended it to be a full scene with the dinosaur walking along a forest pathway, but I wanted to get a drawing posted right away, and I just didn’t have the time to make a full Henderson-esque setting.
UPDATE: The original Acheroraptor drawing has been removed, because it was too inaccurate.
The striking black-white color scheme is 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. Keep your pencils sharp!
- Canadian scientists discover new carnivorous dinosaur species Acheroraptor Temertyorum that lived about 66 million years ago (news.nationalpost.com)
- New raptor species named and on display at ROM (metronews.ca)
- Acheroraptor temertyorum: New Dinosaur Discovered in Montana (sci-news.com)
Ornithomimus (“bird mimic”) is a dinosaur genus belonging to a group commonly known as the “ostrich dinosaurs” or “ostrich mimics”. This name comes from their very ostrich-like appearance, with toothless beaks, long swan-like S-shaped necks, and powerful muscular legs. There are currently two known species of Ornithomimus: O. velox and O. edmontonicus. This genus lived in western North America at the end of the Cretaceous Period, 75-65.5 MYA.
It was most likely omnivorous, and you can tell that by the size of its belly. Plant-eating animals need large guts to process their food, in contrast to carnivorous animals. If you look at specimens of Ornithomimus, or indeed any ornithomimid dinosaur, particularly ones which preserve the gastralia (belly ribs), you will see that they outline the stomach area. In contrast to the somewhat starved bodies portrayed by many paleo-artists following in Gregory Paul’s footsteps, they clearly show a wide belly. Look here to see an example: http://en.wikipedia.org/wiki/File:Ornithomimus_edmontonicus.jpg
People had suspected for a while that Ornithomimus and its kind had feathers. There were two reasons for this. Firstly, there was its obvious bird-like appearance. Anything which looked THAT bird-like just HAD to have feathers! Well, it’s an interesting point in terms of comparative anatomy, but there was really no hard evience to support it, and no real credible analysis of various dinosaur types and their relations to birds which suggested that ornithomimids had feathers. The second reason answered that last point. With advances in phylogeny (determining where different species fit into the scheme of life and how they are related to each other), paleontologists have determined that the ornithomimids belong to a large group of very bird-like dinosaurs called the maniraptorans. This group included the ornithomimids, therizinosaurs, oviraptors, and the “real” raptors – the Jurassic Park-style raptors, specifically the dromaeosaurids and the troodontids. Maniraptorans are the closest ancestors of birds, and many of them are known to have been feathered. This would imply that the ornithomids were feathered as well. This argument was a bit more convincing than the “it looks like a bird so it must have feathers” argument which was around during the 80s and 90s. However, although it made a good point, there was still no physical evidence to back it up. If ornithomimids were feathered, why hadn’t any feather fossils been found in association with their skeletons?
In the early 2000s, that changed. When three specimens were examined more closely, scientists discovered that two of them possessed “quill knobs” (the places where feathers attach onto the bones) on the arms, and a third specimen – a juvenile – actually had feather impressions along its neck, back, and legs. In 2012, a report was published in the academic journal Science demonstrating that at least one ornithomimid species, Ornithomimus edmontonicus, was covered in feathers throughout its life, and that the adults actually had modern pennaceous feathers on their arms forming flightless wings. Click here to see a preview of this article: http://www.sciencemag.org/content/338/6106/510.
This is a drawing of Ornithomimus based upon the findings in that report. As you can see, the arms sport fully-developed albeit flightless feathered wings. Also take note that the feathers do not cover the whole body all around, but only the top and sides – the underside is bare. The color is my own aesthetic guesswork. I decided to make the throat bright red, which (I like to imagine) was used as a courtship display similar to modern reptiles and birds.
Take care, everyone.
Yep, that’s what I heard.
I just found out about five minutes ago, right after I posted my lastest post – a color drawing of Edmontosaurus – that my lovely drawing which I worked so hard on is inaccurate. The first word out of my mouth was…well, I can’t say it here.
Apparently, a specimen of Edmontosaurus regalis was uncovered, dating to approximately 75 MYA, which sported a rounded fleshy comb right above its eyes. That was completely unexpected. For years, I (and I think everybody) assumed that crests were solid bony things on dinosaurs, like on Parasaurolophus or Lambeosaurus. The idea that a hadrosaur could have a soft wobbly crest on its head like a chicken had never occured to me.
I guess that means that I’ll have to get rid of my drawing, but I don’t want to. All I know is that I’ll have to seriously re-think about how I draw dinosaurs from now on.
- Fleshy head comb found on Edmontosaurus near Grande Prairie – Edmonton Journal (edmontonjournal.com)
- The dinosaur that looked like a CHICKEN: Edmontosaurus had fleshy ‘rooster comb’ and a beak-like mouth (thisismoney.co.uk)
- Alberta dinosaur’s head adorned with fleshy comb – CBC.ca (cbc.ca)
- It’s a Duck, It’s a Rooster, It’s a … Dinosaur? (livescience.com)
- Duck-billed dinosaur had rooster-like cock comb (newscientist.com)
- Dinosaurs Continue to Baffle Scientists (guardianlv.com)
Edmontosaurus was a type of hadrosaur, commonly called a “duck-billed dinosaur” which lived in western North America at the end of the Cretaceous Period, dating from approximately 75-65.5 MYA – that’s right, another Hell Creek dinosaur! Currently, there are two species: E. regalis and E. annectens.
Edmontosaurus, named after Edmonton, Canada, was one of the more common of the hadrosaurs; bone beds with hundreds of individuals have been uncovered. Edmontosaurus was big, too, measuring 40 feet long, the same size as Tyrannosaurus. Apparently, it was also prey for T. rex, because at least two specimens show that it had been bitten and survived.
The color drawing that you see here was made with Crayola and Prismacolor colored pencils. I’ve always associated Edmontosaurus with a sort of brownish-tan stripy color pattern, and so that’s what I’ve conveyed here. Just to add a dash of color, I made the keratinous frill running down his neck, back, and tail bright red. There may actually be a bit of evidence to support this. Several years ago, an Edmontosaurus “mummy” was uncovered in the Hell Creek Formation. When paleontologists looked at the preserved scale patterns on the skin, especially on the tail, they saw that the scales were arranged in vertical bars where you had large scales divided between sections of smaller scales. Could this be potential evidence for stripes? Until pigmentation cells are found in an Edmontosaurus mummy, that question will remain unanswered.
At least now I have a color prey dinosaur for my color T. rex to munch on! Keep your pencils sharp, everybody!
Ever since I put my “Tyrannosaurus rex head” and “Tyrannosaurus rex body” drawings on this website months ago, visitors to this blog have always been looking at them. I know that because I regularly view my visitor stats when I log on, and I am always pleased to see that these two posts are always clicked on. Obviously all of you out there in web-world like them. Thank you. It makes me feel good to know that my work is appreciated.
In keeping with the popularity of these posts on the king tyrant lizard, I have decided to add another one. This one is a color pencil version of my T. rex body drawing, which I posted earlier. I used a combination of Crayola and Prismacolor colored pencils. I chose to make it in a striped green color with a pale tan underside and with black lower legs just to add some eye-catching color contrasts. This color pattern was unusual for me, since I mostly associate Tyrannosaurus with a sort of reddish-brown color. I should point out that we have absolutely no idea whatsoever what color T. rex was. However, since it is hypothesized with some credibile evidence that T. rex lived in forested environments, this color pattern seemed logical.
Hope you enjoy.
It’s just dawned on me that all of the art which I have posted on this blog has been paleontology-related. It’s about time that I did some ancient illustration.
For my first subject, I have chosen a character that I became fascinated with when I was in high school, and am still fascinated with to the present day – Attila the Hun (406-453 AD). This is actually the second drawing that I made of him, way back in 2006 – the first drawing wasn’t that good, but it had more or less the same theme. Allow me to describe his appearance in some detail. Upon his head, he wears a gold ribbon. Hunnic kings and chiefs wore crowns, but since Attila was a bit more simplistic, I gave him a gold ribbon instead. Around his neck is a mirror medallion, which was used by the Huns and other steppe tribes to ward off evil spirits and bad luck. Upon his shoulders, he wears a mantle of black fur.
Attila terrorized Rome from 441 onwards, when he launched his first invasion of the Eastern Roman Empire (during the 5th Century AD, Rome was split in two, a Western half and an eastern half). He conquered an area stretching from the northern Caucasus Mountains into eastern France and northern Italy. He died in 453 AD, reportedly of a hemorrhage, although several historians have speculated that he was assassinated.
This drawing was made entirely with No.2 pencil. Hope you enjoy.
Ceratosaurus nasicornis was a 20-foot theropod dinosaur which lived in western North America during the late Jurassic Period, about 155-145 million years ago. It is one of the more famous Jurassic meat-eating dinosaurs, along with Allosaurus and Ornitholestes. It is the second-most-common theropod found within the Morrison Formation.
There are several anatomical features which make this animal distinct. Firstly, and most obviously, it has a small flat horn shaped like half of a dinner plate on the end of its nose, as well as a pair of horns over the eyes. These features are almost certainly visual in nature and were not designed for combat. Many paleo-artists, notably Gregory Paul, like to show the horn as being very large and triangular. I might be wrong, but I instead decided to portray the horn as it appears on the skull – low and rounded, not tall and pointy.
This animal also has a single row of scutes or osteoderms – small knobs of bone – running down the middle of its back, extending from the back of the head all the way to the tip of the tail. Many examples of paleo-art show Ceratosaurus with multiple rows of osteoderms, like the South American abelisaurid theropod Carnotaurus. This, however, is not true – Ceratosaurus just had one row of these bony bumps.
Ceratosaurus had unusually large teeth in its upper jaw in proportion to the rest of its head. This is a clue that this particular animal engaged in what is called “hatchet-style” biting and feeding, where the animal opens its jaws as wide as it possibly can, and then forcibly slams its head downward on its prey like a guillotine.
It possessed four fingers on each hand, which indicates that it was of a much more primitive stock than contemporary theropods, which were more advanced and had only three fingers on each hand. Its primitiveness also means that Ceratosaurus was probably less intelligent than other theropods. Granted, big bad Al was no genius either.
Finally, its tail was unusually wide, and some have suggested that because of this, Ceratosaurus might have been a good swimmer.
This drawing was made with a combination of Crayola and Prismacolor colored pencils. No.2 pencil was used for shading.
Camptosaurus dispar was a type of ornithopod ornithischian dinosaur which lived in western North America during the late Jurassic Period. It measured 20 feet long and possibly weighed a ton. Camptosaurus was the largest ornithopod found within the Morrison Formation. Other ornithopods include the 10-foot long Dryosaurus and the 5-foot long Othnielia.
Camptosaurus was discovered on September 4, 1879 by William Reed in Wyoming during the famous “Bone Wars”. Othniel Charles Marsh originally named the animal Camptonotus, but was forced to change it because another animal had already been given this name. In 1885, the dinosaur was re-named Camptosaurus.
For a long time, we thought we knew what Camptosaurus looked like, or at least what its head looked like. Publications as recent as the 1990s depicted Camptosaurus with a boxy rectangular-shaped skull. This is due to paleontologist Charles W. Gilmore. In 1909, Gilmore wrote a description of the genus Camptosaurus and its assorted species. A skull (YPM 1887), referred to in 1886 by Marsh as belonging to Camptosaurus amplus, was re-designated by Gilmore as belonging to Camptosaurus dispar. In 1980, Peter Galton and H. P. Powell stated that C. nanus, C. medius, and C. browni were not separate species, but were instead growth stages of C. dispar, making C. dispar the only valid species. They also used the skull catalogued as YPM 1887 as the skull of Camptosaurus dispar. For many years, this was taken as fact, and this skull was used in many illustrations of Camptosaurus. However in 2006, Kenneth Carpenter and K. Brill found that this skull actually belonged to a different dinosaur. The skull, and the animal associated with it was named Theiophytalia kerri.
Below is the traditional-but-incorrect depiction of what Camptosaurus‘ skull looked like. Image from The Dinosaur Data Book, by David Lambert. New York: Avon Books, 1990. Page 180. The original image has been modified so that the labels have been removed.
So what did Camptosaurus really look like? The skull was more triangular in shape, similar to that of Dryosaurus. However, it was not a close relative. According to current phylogenics, Camptosaurus was more advanced than Dryosaurus, but more primitive than Iguanodon and hadrosaurs.
The illustration which you see below is the current look of Camptosaurus. However, I should state that the old rectangular image is so prevalent that it will take quite some time before old-school paleo-buffs like me learn to disregard it. This drawing was made with regular No. 2 pencil (my favorite medium) on basic computer paper.
Keep your pencils sharp, everyone.
Allosaurus fragilis is one of the most famous and easily-recognized dinosaurs. Practically every museum has at least one specimen, either on display or in collections, and absolutely every basic-level children’s book about dinosaurs mentions Allosaurus, usually accompanied with a picture.
Allosaurus lived in western North America during the late Jurassic Period, from 155-145 million years ago. Its fossils have been found in rocks known as the Morrison Formation. It measured a colossal thirty-five feet long (half of it being just the tail), making it the largest carnivore in its environment (Torvosaurus comes in a close second, and Saurophaganax might just be an unusually large Allosaurus). It was also the most numerous. More fossils have been found of Allosaurus within the Morrison Formation than all other theropod dinosaurs combined. In fact, we have so many fossils of Allosaurus, ranging from juveniles up to fully-grown adults, that paleontologists know more about Allosaurus than any other meat-eating dinosaur. In all likelihood, it was the top predator in its environment, sometimes (and appropriately) referred to as “the lion of the Jurassic”.
This drawing was the culmination of years of drafting and revision. As you can tell by the coloration, it is heavily influenced by the color patterns seen on the Allosaurus in Walking with Dinosaurs, but I chose not to make the crests red. The first copy was made when I was just starting college, and that stuck around in my house for a couple of years. Then, I changed the proportions and slightly altered the color scheme. Finally, I added greater textural realism and made the colors substantially darker (on the original and second drafts, the gray was so light that it almost looked white). The hardest thing that I had to work on were the hands – I just couldn’t seem to get them right. When I was volunteering at the American Museum of Natural History, I spent about a half-hour taking numerous photographs of allosaur hands to get the right proportions. I also decided not to make the lacrimal crests too large, but instead kept them exactly as they appeared on the skull – I call them “doorknobs with dimples”. I’m sure that I’ll get some paleo-related flak for my decision NOT to make the characteristic large shark fin-like crests in front of the eyes which many paleo-artists put on their Allosaurus drawings, paintings, and sculptures, but it’s my decision and I like my beast’s head just the way it is.
This drawing was colored using no.2 and no.3 pencils (which I almost NEVER use!) and Crayola colored pencils. I hope you like it.
UPDATE: A revised version of this drawing was created and uploaded in July 2020. You can see it here.