Specimen Name & Sex: Jean (female)
Specimen Height: 2.8m
Specimen Length: 6.4m
Specimen Weight: 2.7 tonnes
Stegosaurs are among the most charismatic of all dinosaurs. Where tyrannosaurs have tiny limbs, ceratopsids have spiky head ornamentation, sauropods have long necks, and hadrosaurs have “duck bills,” stegosaurs have some of the most defining “dinosaurian” traits; the dorsal plates and the thagomizer. The arrangement and function of the plates is a debate dating back to Stegosaurus‘s discovery in the late 1800s by Othniel Charles Marsh. Marsh hypothesized the plates would be arranged in a manner similar to that of a pangolin, where they covered the entire animal. This is where the name Stegosaurus comes from — “covered reptile.” Of course this restoration is outdated. S. stenops and its sister species S. ungulatus have somewhere in the neighborhood of 18-24 plates (depending on who’s counting) that run at least semi-bilaterally along the animal’s back. I have elected to keep the plates as display structures, disregarding hypotheses of temperature regulation due to the probable existence of a layer of keratin covering the vascular structures. Here, Jean is shown with the plate arrangement based on the subadult Sophie specimen currently housed in London, which has an astounding >90% completeness!
She’s also not much larger than Sophie. S. stenops was the smaller of the two recognized species of Stegosaurus, with mass estimates close to that of a rather porky rhinoceros. Despite a comparatively smaller size to some contemporaries (Brachiosaurus, Brontosaurus, Diplodocus, etc.), Jean and the rest of her kind were rather successful, low-browsing ornithischians. The recent find of further neck vertebrae extends the stationary feeding range of a steg, allowing it to stand in one place and clear a larger volume of plant matter than it would with the typically-renditioned stubby neck.
Skeletal reference by Scott Hartman.
What strikes me the most about the new Stegosaurus is the strange plate arrangement along with the proportionality of said plates. To an extent, they appear asymmetrical as opposed to the more traditional reconstructions with a very clear, very concise shift in size from the neck to the hip and then tapering towards the end of the tail. It’s come to my attention that I also might’ve placed the plates too low, so Jean might get a refurbishment in the near future (nothing major, just adjusting the plates and maybe her head). Maybe a pattern update, too?
The duality of the blue and pinkish tones on Jean is something I consider to be my trademark for Stegosaurus. I interpret stegosaurs to be docile, rather skittish animals. The big eyespots on the plates were meant to deter attacks from predators, with the thagomizer acting as a last resort. The thagomizer was no laughing joke, however. The strength of the tail was more than capable of lodging a spike deep into any opposing party. I complemented the tail spikes with some sharp keratin barbs, just in case the animal lost or broke a spike in combat.