In 2014 Winter, I was looking for a project that I can reconstruct ancient creatures for the project of Natural Science Illustration course at the University of Washington. Fortunately, I could meet Dr. Wilson, Burke Museum adjunct curator of vertebrate paleontology and University of Washington associate professor of biology and he showed me the fossilized teeth and the skull cast of Didelphodon vorax.
The fossilized teeth of Didelphodon vorax.
The reconstructed skull cast of Didelphodon vorax.
Systematic study of four mammals. Skull, teeth, and muscles are superimposed partially.
Didelphodon vorax is one of the largest North American Late Cretaceous mammals so far discovered and was probably about the size of a small domestic cat. Dental features and the cranial structure suggest that this species was probably predator and/or scavengers. The jaws are short and massive and bear enormous bulbous premolar teeth which appear to have been used for crushing. It probably had an omnivorous diet, possible for feeding on molluscs, dinosaur eggs, lizards and plants. The recently found specimen, located just 40m away from a Triceratops in a riverbed, shows the Didelphodon possessed on otter-like body with a Tasmanian devil-like skull. (Nature Communications 7, 13734 (2016) doi:10.1038)
What I did first was a systematic study of the Didelphodon vorax. I asked Burke Museum to pull out some skulls that are morphologically similar to Didelphodon. Thanks to their help, I could see coyote, opossum, Tasmanian devil, and others. Didelphodon vorax has already reconstructed by some artist before, but the reconstructions were all look close to opossum (as long as I know). By studying the new fossil specimen and other skulls, the specimen is more robust than opossum and does close to Tasmanian devil, as the study description says. So I decided to mainly use Tasmanian devil as the reconstruction model.
I tried to illustrate a "tough" creature to show it's powerful teeth and muscle. One of the most interesting features of Didelphodon skull that I found was the "marsupial mandibular angular process" (pointed in the last figure.) This process is similar to extant marsupials and associated with insertion of a neomorphic superficial division of the medial pterygoid musculature, which is not seen in extant eutherians. This muscle complex assists closing force of the jaws.
I chose the scene that two Didelphodon vorax preying on an egg and baby and Troodon formosus that possibily lived in the same place and time.