This is the second of five blogs by Dr. Jordan Mallon profiling the contestant fossils featured in the museum’s Dino Idol contest. From February 16 to March 17, visit the museum and choose your favourite from among five dinosaurs, whose bones are sealed away in plaster field jackets.

The second specimen I’ll cover is what we’ve imaginatively called the Mystery Jaw. It was originally collected in 1914 by Charles H. Sternberg and his three sons. The fossil comes from what is now Dinosaur Provincial Park (“the Park”), 48 km north of the town of Brooks, Alberta. To my mind, what make this specimen so interesting are the scant suggestive details that C. H. Sternberg provided in his field notes. He wrote only that that this is a “carnivorous dinosaur jaw”, and nothing beyond that.

Jordan Mallon puts hand on the plaster jacket for Mystery Jaw.
The jacket containing the Mystery Jaw on display for Dino Idol. The writing on the jacket tells us that it was the fifteenth specimen collected by CMS (Charles M. Sternberg) in 1914. Image: Dan Smythe © Canadian Museum of Nature.

To date, roughly a dozen carnivorous dinosaurs have been named from Alberta, but I think we can narrow the possibilities for Mystery Jaw down to a couple of likely candidates.

A small motorboat tows a raft with a tent on it.
The Sternberg family would regularly use scows like this to make their way down Alberta’s Red Deer River in search of dinosaur fossils such as Mystery Jaw. Sometimes the scow would get hung up on a sandbar and have to be towed by motorboat to deeper waters. Image: Charles H. Sternberg © Canadian Museum of Nature.

Judging by the size of the specimen (the field jacket is a few feet long), the jaw must have belonged to a very big animal. In fact, the only carnivores from Alberta massive enough to have possessed jaws of this size were the tyrannosaurids. These include such forms as Gorgosaurus, Albertosaurus, Daspletosaurus, and Tyrannosaurus. Knowing also that the jaw came from the Park, where the sedimentary rocks date to between 77 and 75 million years old, only Gorgosaurus and Daspletosaurus are likely candidates for Mystery Jaw as the others are too young (i.e. are not found from this time period).

Colour illustration of Gorgosaurus.
Mystery Jaw probably pertains to a tyrannosaurid, like the fleet Gorgosaurus depicted here. Image: Brett Booth © Canadian Museum of Nature.

As it turns out, Daspletosaurus is quite a rare beast, and the Canadian Museum of Nature is fortunate to have in its possession one of the few (and best) examples of this animal on display in the Talisman Energy Fossil Gallery.

If the Mystery Jaw proves to be from a Daspletosaurus, it will undoubtedly provide valuable information about this animal’s evolution and anatomy. I’m particularly interested in learning more about the ecology of this animal, and how it might have differed from that of its rival, Gorgosaurus.

Panorama of dinosaur skeletons in Talisman Energy Fossil Gallery.
A mount of Daspletosaurus torosus dominates the entrance of the museum’s Talisman Energy Fossil Gallery. Image: Martin Lipman © Canadian Museum of Nature.

Of course, we’ll only know for sure what the Mystery Jaw is if it gets enough of your votes, so that it will then be opened and studied as a research project!

So please come visit the Canadian Museum of Nature until March 17, where your admission gets you a ballot to vote for your favourite Dino Idol contestant in person.

Please stay tuned for next week’s entry on our third Dino Idol contestant, the aptly nicknamed Stumpy.

Read previous blogs about the Dino Idol contestants:
Dino Idol Contestant #1: Headrosaur—A Head Without a Body!