Tag Archive for: EARTH

GORGOSAURUS SKELETON

Gorgosaurus spec.

Late Cretaceous (approx. 77 million years ago)

Judith River Formation, Choteau County, Montana

Exhibition-ready mounted skeleton, measuring 9 feet, 2½ inches tall (110.5 inches, 113.5 with armature), just under 22 feet long (263.5 inches). Skull measuring 38½ by 26½ by 17 inches (97.8 x 67.3 x 43.2 cm). 79 fossil elements, mounted on custom armature with additional cast elements.

The Gorgosaurus roamed the Earth about 77 million years ago, roughly 10 million years before it’s more famous relative, the T-Rex. Well-preserved until it was discovered in 2018 at Montana’s Judith River Formation, this particular specimen is a great example of this apex predator.

Standing around 10 feet tall and 22 feet long, it’s one of one a few ever found in the US, and the only known example not in a museum or large collection. It’s going up for auction as part of Sotheby’s Natural History sale in New York on July 28, and is expected to sell for up to $8 million.

THE FIRST SPECIMEN OF ITS KIND TO COME TO AUCTION —ONE OF ONLY ABOUT 20 KNOWN EXAMPLES, AND THE ONLY KNOWN TO BE AVAILABLE FOR PRIVATE OWNERSHIP

UNLIKE OTHER DINOSAURS SKELETONS THAT HAVE RECENTLY COME TO MARKET, THIS SPECIMEN HAS NOT YET BEEN GIVEN A NICKNAME — THE NEW OWNER WILL GET TO PICK THE NAME OF THEIR CHOICE

Gorgosaurus was a predatory dinosaur whose name means “dreadful lizard”. It was a bipedal, apex carnivore that lived approximately 76 million years ago in what is now western North America.

It is believed that Gorgosaurus’ body reached lengths of nearly 30 feet and weighed in at around three tons, and paleontologists have been able to make educated depictions of its body-shape based on the very small number of fossil skeletal remains that have been discovered thus far. What we can see is that at the end of a massive S-shaped neck, a huge head was held that housed dozens of long, slim, double-edged serrated teeth.

The dentition in the front of the snout were D-shaped, and those in the rear of the jaws appearing oval in cross section, which were ideally designed for piercing and cutting. Its leg proportions were more typical of swift-moving biped dinosaurs, and its long tail acted as a counterbalance while running. Paleontologists speculate that Gorgosaurus might have used these adaptations to hunt herbivorous contemporaries including the hadrosaurs Lambeosaurus and Corythosaurus, the ceratopsians Styracosaurus and Centrosaurus, and the armored ankylosaurs Edmontonia and Euplocephalus.

The fossil record indicates that Gorgosaurus coexisted with the less-widely distributed but similarly-sized theropod, Daspletosaurus, with whom they competed for resources. Both were members of the family Tyrannosauridae, which includes both North American and Asian super predators such as TyrannosaurusTarbosaurusAlbertosaurusDaspletosaurus, and others. Gorgosaurus itself predates Tyrannosaurus rex by about 10 million years. They are considered a cousin species to Tyrannosaurus rex, and a crucial piece in the understanding of the evolutionary diversity of the entire Tyrannosaurid family.

Condition & Detail Images

The bones are preserved in exquisite detail, exhibiting little distortion and retaining much of their original shape and surface characteristics. Overall, the fossilization of this Gorgosaurus is superb. The patina is a light to medium brown, a color consistent with most vertebrate fossils from the Judith River Formation. There is no sign of “pyrite disease” or other mineral issues that would represent a problem with future preservation of the fossils.

The skull is represented by a beautifully preserved left maxilla and an assortment of cranial bones. The left side of the skull is well represented including the preserved maxilla and the three major bones that create the rounded orbit. The shape of orbit is a distinguishing feature between Gorgosaurus and Tyrannosaurus. The maxilla includes two fully rooted exposed teeth, three partial teeth, and five unerupted teeth in their alveoli. The maxilla, overall, shows very little distortion and is large as compared to other Gorgosaurus maxillae.

The Gorgosaurus specimen contains a well-documented axial skeleton with material representing the cervical, dorsal, and caudal vertebrae. The axial skeleton also includes an exceptionally well-preserved pelvis, with all eleven elements represented including complete articulated pubis bones.