A New Skull of Styracosaurus

Overhead view of Styracosaurus albertensis skull. From Robert Holmes and Anthony Russell (2007) “A revision of the Late Campanian centrosaurine ceratopsid Stryacosaurus from the Western Interior of North America” Journal of Vertebrate Paleontology 27(4): 944-962.

A description of a new Styracosaurus skull came out just today.i Styracosaurus is one of the more familiar ceratopsians. The ceratopsians are the dinosaurs that are related to Triceratops. For the most part, the ceratopsians look a lot like each other, differing primarily in size and in the ornamentation on their skulls. Styracosaurus is the one that has a ring of spikes coming from its frill.

The main species of Styracosaurus is Styracosaurus albertensis. There is a second species that was originally named Styracosaurus ovatus, but it was later renamed as Rubeosaurus ovatus, placing it in a separate genus. The principle difference between Styracosaurus and Rubeosaurus lie in the orientation of the spines on the frill. In Styracosaurus, the horns all bend out from the middle so that they curve outward along the frill. In Rubeosaurus, the first pair of horns are directed toward the middle, bending inward, rather than outward.

The newly discovered Styracosaurus may alter our understanding of the differences between Styranosaurus and Rubeosaurus. This new skull has a lot of peculiarities, such as the first pair of horns pointing almost straight back, putting it between the horns found in most Styracosaurus and Rubeosaurus. In fact, the paleontologists who described the new skull suggest that Rubeosaurus should not be a separate animal, that it is in fact the same animal as Styracosaurus. Basically, they point out that Styracosaurus has enough variation in the shape of its horns that Styracosaurus should include both Styracosaurus and Rubeosaurus.

The top part of the frill of Rubeosaurus ovatus. Notice that the inner pair of spikes point toward the middle, unlike what is seen in Styracosaurus albertensis. From Robert Holmes and Anthony Russell (2007) “A revision of the Late Campanian centrosaurine ceratopsid Stryacosaurus from the Western Interior of North America” Journal of Vertebrate Paleontology 27(4): 944-962.

The paleontologists said a little bit more, too. They noted that the new Styracosaurus has a pair of small, hook like horns right in the middle of the frill, which resembles another ceratopsian, Ceratosaurus. However, they did not suggest that Styracosaurus and Ceratosaurus are the same animal, they they considered the possibility that they are related to each other.

The new Styracosaurus skull. From Andrew Lyle (2019) “Dinosaur skull turns paleontology assumptions on their heads” Phys.org, retrieved from https://phys.org/news/2019-11-dinosaur-skull-paleontology-assumptions.html on November 26, 2019.
The frill of Centrosaurus. Notice the pair of small, hook-like horns in the top middle of the frill, much like the small pair found on the new Styracosurus. From Joseph Fredericksen and Allison Tumarkin-Deratzian (2014) “Craniofacial ontogeny in Ceratosaurus apertus” PeerJ 2:e252 https://doi.org/10.7717/peerj.252.

New fossil discoveries, like this new skull, can change our perspective of dinosaurs quite rapidly. It should be pointed out, however, that none of what was said about this new Styracosaurus should be a surprise to those who hold a Biblical view of the world. We are told in Genesis 1 that God created the animals after their own kind. A kind encompasses the whole gene pool of a type of animal. Everything within the kind are related to each other and we should expect all sorts of variations with that kind. There is a good chance that most, if not all, of the ceratopsians belonged to the same kind, so the fact that Styracosaurus, Rubeosaurus, and Centrosaurus all share common features is not a surprise: it is what we expect.

iRobert Holmes, Walter Persons, Baltej Rupal, Ahmed Qureshi, and Philip Currie (2020) “Morphological variation and asymmetrical development in the skull of Styracosaurus albertensisCretaceous Research 107, retrieved from https://www.sciencedirect.com/science/article/pii/S0195667119301946?… on November 26, 2019