Hello. On August 21-23, 2024, I hosted a three-part Zoom lecture series on what North America looked like during the time that the dinosaur Utahraptor was alive during the early Cretaceous Period 135 million years ago. Utahraptor’s fossils are currently… Read More ›
Cedar Mountain Formation
Siats
Introduction Siats, whose name is in reference to a monster from native Ute folklore, was a large meat-eating dinosaur which lived in Utah during the middle Cretaceous Period 98 million years ago. As far as we know, Siats was the… Read More ›
Gastonia
Introduction Gastonia was an armored dinosaur measuring approximately 16.5 feet long which lived in western North America during the early Cretaceous Period approximately 135-130 million years ago. The first specimens were found in eastern Utah in 1989, and more have… Read More ›
One Little, Two Little, Three Little Therizinosaurs
And today’s topic which is sure to start an argument is…Are there three different species of Falcarius within the Yellow Cat Member of the Cedar Mountain Formation? The basal therizinosaur Falcarius utahensis, which was officially named and described in 2005… Read More ›
Acrocanthosaurus
Acrocanthosaurus, meaning “high-spined lizard”, was a large 35 foot long meat-eating dinosaur which lived in North America during the middle of the Cretaceous Period approximately 115-110 million years ago. It is distinctive for the unusually tall neural spines on the… Read More ›
Gigantoraptor
Gigantoraptor was a massive 25-30 foot long oviraptorosaurian theropod dinosaur which lived in eastern Asia (and possibly in North America) during the middle of the Cretaceous Period. The fossils of this enormous bird-like dinosaur, consisting of a partial skeleton, were… Read More ›
Toxolophosaurus
Introduction Allow me to introduce you to Toxolophosaurus, “the bow-crested lizard”, which lived in Montana during the early to middle Cretaceous Period approximately 135-115 million years ago. Despite its name, Toxolophosaurus wasn’t either a dinosaur or a lizard. Instead it… Read More ›
Cifelliodon
Cifelliodon was a prehistoric mammal which lived in Utah during the early Cretaceous Period approximately 135 million years ago. The only specimen which we have of this animal is a single upper jaw measuring 2.75 inches (7 cm) long which… Read More ›
Goniopholis: The Typical Mesozoic Crocodile
Dinosaurs ruled the land during the Mesozoic Era, but crocodiles and their relatives unquestionably ruled the water. Prehistoric crocodiles are usually relegated to the background as supporting actors or extras in our imagined Mesozoic dramas, but the truth is that… Read More ›
List of My Articles on the Cedar Mountain Formation
The reconstructed skull of Utahraptor, on display in Brigham Young University’s Museum of Paleontology. Photo by Jaren Wilkey of Brigham Young University (January 26, 2018). Creative Commons Attribution-Share Alike 4.0 International license.https://commons.wikimedia.org/wiki/File:BYU_Utahraptor_skull.jpg. The Cedar Mountain Formation is a North American geological formation which… Read More ›