More Ceratopsian Madness!!!

Posted by Nima On Monday, May 4, 2009 11 comments

Hey everyone, it's been a messy past few weeks so progress was literally snail paced. I was sick with the flu, my computer was infected with spyware (and had to be rebooted) and I had a mess of exams and other issues to tackle...

But I did want to get some artwork done, and the fact that the ArtEvolved blog seemed a bit lacking in Chasmosaurs for its Ceratopsian Gallery just screamed out for attention. Chasmosaurus itself has always been my second favorite dinosaur (after Brachiosaurus) and it's a fitting challenge for a high-detail illustration.

And instead of simply being ripped apart by a predator, I wanted to show this ceratopsian fighting back.

I'd had this image in the back of my mind for a while, a Chasmosaurus charging at a predator whose attack failed. Lunch strikes back. This concept was actually inspired by a drawing John Conway did, of Chasmosaurus belli chasing away a Daspletosaurus torosus. You can see his drawing HERE.

And the image stuck in my head. This was one of those pieces where you just look at it and you get this insane burning desire to do something like it, only with your own personal twist. I HAD to do something like that. And it would HAVE to be better than Conway's already impressive version (at least to my eyes). Now Conway's work is under a creative commons license that requires you to credit the artist if you "use" his work - so this would technically be illegal if I didn't give him credit. So of course I will. The dinoart community, as small as it is, doesn't need any lawsuits - no Sue fiasco, and no Archaeoraptor either.

Only thing is, I planned to change the Chasmosaurus belli to a Chasmosaurus kaiseni (which I still consider a separate species) because I wanted something with much more impressive horns.

Above: skull of Chasmosaurus kaiseni.

Below: Chasmosaurus kaiseni in the foreground, compared with Chasmosaurus belli in the background (both skulls are in the AMNH).

I also decided to replace the Daspletosaurus with an Albertosaurus, which was more common at that time in Chamosaurus's Canadian habitat. Aside from that, I'm not a particularly big fan of Daspletosaurus getting chased by its prey... not really sure why, but for the dynamics of the scene, Albertosaurus just looks better in my mind. I'm NOT a follower of Dale Russell's theory that Daspletosaurus was the main predator of horned dinosaurs while Albertosaurus stuck mostly to duckbills (I don't buy most of Russell's theories period, but that's another story). And nothing screams 'Alberta' like Albertosaurus. So I replaced the Daspletosaurus with a subadult Albertosaurus libratus.

Thus I completely replaced the head (BTW, in any case the original head doesn't exactly resemble Daspletosaurus either - it's a lot shallower and more crocodylian than the actual skull of Daspletosaurus - and the notch in the upper lip just looks odd on any advanced tetanuran - it's almost Dilophosaurian up close! For reference see below...)

Left: Daspletosaurus skull. Right: John Conway's Daspletosaurus. I marked both with diacritical lines added to show the discrepancies: Red = lip line: smooth in the skull, notched in the drawing. Pink = depth of the skull about halfway between the eye and the nostrils: unusually shallow like a croc or phytosaur in the drawing. Yellow = depth of lower jaw at a position corresponding to the lacrimal bone in the upper skull: moderately shallow in skull, unusually deep in drawing). Green circles = orbital horns: small, unfused, and upward-pointing in the skull, but wide, flat, and and fused in the drawing. Blue line = incline of snout just below preorbital ridges and rugosities: steeper in the skull than in the drawing, which is the only possibility considering the proportional differences in snout depth!

Of course the skeptical can always look at the untouched originals. Conway's piece is indeed detailed, well thought-out and very skillful in perspective... it's just not Daspletosaurus. Yes I know I'm being harsh; it's nothing personal, just the art. John Conway is overall a very accomplished and talented artist who I'd probably say easily outranks 95 % of paleoartists out there - his Daspletosaurus, for all its errors, is far more accurate than, say, the work of Ely Kish or Josef Moravec (...don't even get me started...). Of course, such critiques of my own work are equally welcome. It's how we all improve.

But back to Albertosaurus: it was a more common predator, had a longer snout, and is relatively easier to draw. The body was pretty similar to Daspletosaurus, but more slender - though in this seemingly subadult stage depicted in Conway's drawing, they would both have been of similar physique.

*** A NOTE ON ALBERTOSAURUS: Phil Currie and a few other paleontologists have recently re-labeled A. libratus with its original 1920s name, "Gorgosaurus libratus" - though going on Gregory Paul's more reliable classification, I decided there isn't enough difference between A. libratus and the type species A. sarcophagus, to kick the former out of the genus Albertosaurus.) I still think there are enough similar derived traits between A. libratus and A. sarcophagus to consider libratus as a member of Albertosaurus.***

Long story short, I first emailed Conway to make sure it was okay to draw the scene with the changes I have described above. He replied that it was fine, and even claimed that he probably didn't own the poses of the dinosaurs in his image... in any case he seemed pleased that I would give him credit for the original concept.

After that, I started work on the drawing. There were a number of mostly small issues that needed resolving.

*First I lengthened the predator's tail (based on the most current skeletal proportions of Albertosaurus; Daspletosaurus skeletons also had similar proportions, and Conway's Daspletosaurus seemed unusually short-tailed, and the tail looked a bit too stiff).

*I reduced the rather extreme and improbable angle of the predator's head-turning (as well as raising the head and making the neck larger) - in any case, both Albertosaurus and Daspletosaurus had eyes that faced sideways, so the ideal head position for the predator to keep its eye on the charging Chasmosaurus would be a profile.

*I curved the end of Chasmosaurus's tail more upward to stay clear of its hind legs

*I added a skin flap to enclose Chasmosaurus's shoulder retractor muscle (latissimus dorsi), which itself seems strangely absent in Conway's version.

*I also added skin flaps for the caudofemoralis muscles on both animals (look at Greg Paul's 1988 T.rex pair painting to get an idea of how this would look from behind).

*I lowered the angle of the predator's arm and made it larger to properly scale with the body (the arm angle and size on the Conway original looked more Abelisaurian than Tyrannosaurian).

*I gave the predator an open mouth with tongue showing (as if panting).

*I put sharper outlines on the Chasmosaurus frill studs and other small facial features.

*I enlaeged the corner studs on the frill (as well as re-scaling their perspective and the rest of the upper frill).

*I altered the stance of the Chasmosaurus's hands and fingers, to a more impact-absorbing one (the dinosaur is jumping and eventually will have to land on its fingers, not its carpal bones).

*I did a TOTAL redesign of the skin textures for both animals - more detail, more wrinkles, and smaller scales. I also kept in mind the presence of a very rich skin texture of large scute-scales surrounded by smaller ones for Chasmosaurus, based on known Ceratopsian skin impressions - Conway's Chasmosaurus seems unusually smooth considering this.

*I also put some substantial patterns on both animals - stripes for the Albertosaurus, and blotches for his ceratopsian foe.

*I redrew the body of Chasmosaurus to be more in line with the creature's likely musculature (Greg Paul's Chasmosaurus muscular diagram published in Dinosaurs Past and Present (1987) was a very useful reference in this regard). The result was more blocky than Conway's version.

*I drew the segments for the fleshy pads under the Chasmo's toes (you'd think this is easy, but it was insanely tedious. The pads would more or less follow the pattern of the toe bones - but finding a good picture of ceratopsian toe bones was a major pain in the phalanges!) As each toe had a different number of bones, the number of pad segments was also likely to have varied. I also made the Albertosaurus's toe pad segments more defined.

Above is John Conway's drawing from his Paleontography website.


BELOW is my initial sketch.

And further below, is my progress so far. Click on the image to see the full detail. Albertosaurus is finished except for the tongue, the teeth have been redone from the initial sketch to match the skull of A. libratus. Also notice the sharper angles in Chasmosaurus's spine and torso relative to the initial sketch.

Pretty much all that's left is the tongue and the Chasmosaurus's rear half. I hope to finish this soon. And thanks to Mr. Conway for creating the original drawing, being totally cool with my reinterpretation of the scene, and answering my questions.


Zach said...

I really like it, moreso than Conway's original. The texturing is incredible. Do Chasmosaurus belli and C. kaiseni occur in the same formation, at the same time? If so, we could be talking sexual dimorphs, although I'm sure a LOT more material would need to be found before that kind of determination can be made.

Nima said...

As far as I know, there is very, VERY little information on Chasmosaurus kaiseni. It's known from a single good skull that was collected by Barnum Brown in 1913 (it's the same skull that appears in front of the C. belli skull in the photo above). BUT there's no mention of the site in ANY publication I can find... the ONLY clue so far is in Bakker's book "The Dinosaur Heresies" where both C. belli and C. kaiseni are illustrated among the "Horned Dinosaurs of the Judith River formation".

So C. belli and C. kaiseni are both from the Judith River formation, at least that much is known. Going on Bakker's info alone, I suspect C. kaiseni COULD just be a male specimen of C. belli, and the small-horned C. belli type skull would be the female.

It's certainly possible they are just sexual dimorphs. Aside from the horns, their skulls are remarkable similar, FAR more similar to each other than to C.russelli or C. irvinensis with its oddly hooked upper frill flanges. Most paleontologists took this view - reclassifying C. kaiseni as a male C. belli.

But I think Chasmosaurus kaiseni may still have merit - it is after all, not known from much more than the skull, and the nose horn, which is badly eroded, nevertheless shows a different shape than the C. belli specimens... so until more C. kaiseni material is found, I will continue referring to C. kaiseni as such.

Angie Rodrigues said...

Your blog is a gold mine of information, especially for the artist. Your artwork is incredible and I really love how you explain your drawing along the way. This is great!

One of my favorite blogs to follow is yours, so keep it up:)

Brett said...

While both drawings are very nice. I really don't understand why you didn't you just draw something original? I know it's an iconic image for you but why not swap the angle or switch the views?

that being said, I think your versions head is a much better fit. But I think the Chasmosaurus head is a bit large for the perspective you both were going for, but that's and easy fix in photoshop:)



Nima said...

Thanks for the compliments, Angie! I'm flattered :) I aim to make this blog a treasure trove of the kind of dinosaur knowledge that simply can't be found anywhere else. I also can't wait to see more of your vibrant paleo paintings! Got any therapsids in the works?

And Brett, FYI every other dinosaur scene I have ever drawn or am presently working on IS original. This is my only "remix" drawing so far. And while I did consider changing the angle, none of them looked as interesting as the rear view which is so rare in dinosaur "battle scenes". As for the head - indeed it is very big and that can look odd at this angle - but the size is completely accurate.

It's worth mentioning that MOST (but not all) drawings/paintings of ceratopsids for the past 100 years have made the body and tail too big relative to the skull, following Marsh's erroneously long-bellied Triceratops prorsus skeletal diagram. Ceratopsids were always huge-headed and compact-bodied. Some modern restorations (like Angie's Styracosaurus) take the real proportions into account, but many others sadly still don't. Also look at Luis Rey's Torosaurus pair painting on his site - the colossal head/body ratios on it make my/Conway's Chasmosaurus look tame... yet they are totally defensible.

John Conway said...

Hi Nima,

I'm down with a lot of the changes you made. I like your scales more. My drawing's pretty old (2002 or so), and there a lot of things I'd do differently now.

I'm a bit dissapointed you changed the tilted, mouth-closed head to a side-view roaring-to-the-maximum-extreme head though--seems a bit cliché.

Nima said...

Wow thanks for commenting John!

The scales are - to some extent - an obsession. I aim to make my scale textures near-photographic in the future.

As for the roaring - perhaps it is cliche, but eventually so is almost every degree of mouth-openness. Somebody's illustrated it, however open or closed it is. If my prey was chasing me, I'd certainly abandon all hope of silently stalking it with my mouth shut. Maybe even call other Albertosaurs for help.

The reason I changed the head to side view was I didn't really think that twisting the neck as far as you did was totally plausible for a large Tyrannosaur. And your original shows a neck that seemed rather - squinched, for lack of a better word. For a smaller predator, say a Utahraptor or even an Allosaurus, it may have worked (largely because they had longer, thinner necks, so less risk of squinching and breaking cervical ribs, straining the other side of the neck, etc.)

Though for Albertosaurus, I doubt the neck could bend back horizontally that far. And it would have had even less rearward flexibility in Daspletosaurus, whose neck was even shorter and more heavily muscled.

But thanks for the critique. I welcome it.

slippyface said...

Hi, randomer.

I adore the superficially 'realistic' rendering on the dinosaur's skin on the second drawing, but I think that John's drawing has a certain realism that has failed to be achieved with the second one.

Nima said...

slippyface, I don't know where you get this "randomer" title from. Either call me Nima, Paleo King, or Your Majesty. Your choice. But I'm NOT a "randomer", whatever that is.

Furthermore, there is nothing superficial about my drawing. It's based on actual preserved skin impressions. And while you're certainly entitled to your opinion on whose is more realistic, the fact is my interpretation doesn't fail at ANYTHING. Try looking at the finished product before passing quick negative judgments: said... blog.

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