Bringing a Dryptosaurus Back to Life

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In reaction to my post about Dryptosaurus the other week, paleo-artist Michael Skrepnick told me about the efforts of his colleague Tyler Keillor to create a fleshed-out restoration of the dinosaur. I immediately e-mailed Tyler about the project, and he was kind enough to answer a few of my questions.

Brian: I heard that you have created a restoration of a Dryptosaurus head. Can you tell me a little about the background of the project?

Tyler: There's a museum about 50 miles Northwest of Chicago in Wauconda, Illinois, called the Lake County Discovery Museum I'd previously worked with the Exhibits Manager there, Steve Furnett, when we both worked in the Field Museum's Exhibition Department about 10 years ago. Steve was planning a new temporary exhibit called "Prehistoric Lake County," which would show the types of animals and environments that would have existed in the area during different segments of time. Paleontologist/scientific advisor to the exhibit, Richard Kissel, helped determine what types of animals could be shown in the exhibit based upon local fossils that have been found, and then speculatively which types of animals might have lived in the area during other chapters of time, but for which we have no remains to observe directly. This is where Dryptosaurus came in. It was also a toss up between a Hadrosaurus, or a Coelophysis. But (happily) the Drypto. won out for the reconstruction. The head served as a great attractor to get visitors into the gallery, where there were lots of real and cast fossils,  graphic panels explaining what was known and what was presumed to have lived in the area, as well as a great animation by Chicago animator Pat Bradley.

Brian: Despite being one of the first dinosaurs to be known from a partial skeleton, we still do not know very much about Dryptosaurus. How did you go about restoring such an enigmatic dinosaurs? What other dinosaurs did you use for comparison?

Tyler: We started by familiarizing ourselves with all of the known Dryptosaurus remains; as you know, there aren't many! An interesting reference was Thomas Carr's  Appalachiosaurus paper (Journal of Vertebrate Paleontology, 25(1): 119–143) which includes a cladogram with skull silhouettes for the species that are represented. It looks to me like the illustration of the Appalachiosaurus skull served as a template for the Dryptosaurus skull in the cladogram, with the known Dryptosaurus skull bones fitting nicely within the outline. I think it's a fair and conservative glimpse at what a Drypto. skull might have looked like. Fortuitously, I had previously been involved with the Burpee Museum in Rockford, Illinois, for their "Jane" project. Jane is a juvenile tyrannosaur, and while the specimen is beautiful, I did have to sculpt about 40 percent of the skull to reflect parts that weren't preserved in order to complete it. This restored skull model is remarkably similar to that Appalachiosaurus skull illustration. After completing the Jane skull for the Burpee, I then sculpted the flesh reconstruction atop its skull cast. (On display, along with two Mike Skrepnick paintings of Jane as well as the mounted skeleton, in the exhibit entitled "Jane, Diary of a Dinosaur.") Since the size of the Drypto. bones seemed pretty close to those of Jane, I felt pretty good about using my Jane head as a starting point to extrapolate a Dryptosaurus flesh head.

Brian: Your restoration of Dryptosaurus has wispy feathers on it. What made you decide to include them?

Tyler: The feathery covering is of course speculative. However, Richard didn't mind this bit of artistic license, since we can see that Dilong had a feathery coat of some kind. So far, the only skin impressions I'm aware of for tyrannosaurs include tiny rounded scales from footprints, and a description of a dewlap outline (was it for a Tarbosaurus?). So I didn't think that at least some feathers were out of the question. I applied the feathers along the midline of the neck to top of the head, and tapered them out along the sides of the neck. There's another stripe of lighter feathers  lower on the neck, evoking the patterns of apteria and feather tracts of living birds. For a simple filamentous look, I started with ostrich plumes. I stripped the barbs off of the central vane, and then trimmed these to length before individually adhering them.

Brian: One of the most frequently-asked questions about dinosaurs is "What color were they?" What influenced your decisions in choosing colors for Dryptosaurus?

Tyler: I created a few Photoshop mockups of coloration choices for the museum.  My favorite, and one that I'd been wanting to do for a while, had a dark hide ranging from black to dark grey, with a lighter ventral surface. The dewlap gave me a chance to include a pop of color, especially with the possibility that this could have been used as a display structure. I went with a rooster-comb red color for those wrinkled areas of the throat. Overall, a pretty drab coloration, but this actually highlights the eyes, the teeth, the scars, the wattle. In person, it's a pretty scary face to look at!

Brian: Can you describe the process by which you created the restoration? How did it go from an idea to a finished sculpture?

Tyler: I didn't want to make a roaring head, which I felt has been done so many times before by so many artists. My personal anatomical philosophy for theropods includes a sealed oral margin (with teeth covered) when in closed-mouth pose, but this would eliminate a lot of the "wow" factor for the museum. So I thought a slightly parted mouth would be a good way to show some teeth, and also represent an unusual pose: as if the animal is panting slightly, or gaping a bit and employing gular flutter to thermoregulate. I also modified the eye size and orientation from previous models I'd done, using some recent studies for reference. By partially closing the eyes, the head took on an eerie, contemplative appearance. I added lots of scars, both healed and fresh, to represent some of facebiting wounds Drypto. may have suffered as other tyrannosaurs did, if not scars from the dangerous predatory lifestyle. Using my Jane molds as a starting point, I resculpted the pose of the jaw and neck, changed the length of the teeth, added a dewlap, resculpted the eye and lacrimal area, changed the nostril openings, added scarring, etc. The display cast is polyurethane resin, with glass eyes, painted with acrylics. I use dental acrylic for the teeth, so they have a natural translucency when viewed from different angles.

Tyler's Dryptosaurus restoration can be seen at the Lake County Discovery Museum in Wauconda, Illinois.

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