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Tyrannosaurus rex skull on display at the University of California, Berkeley. EncycloPetey/Wikipedia (CC BY-SA 3.0)

Rare 66.3 Million-Year-Old T. Rex Skull Discovered in Montana

Major fossil find from the dinosaur graveyard.

| 2 min read

Major fossil find from the dinosaur graveyard.

At the tail end of the Cretaceous period, some 66-68 million years ago, Tyrannosaurus rex roamed the forested river valleys of western North America. Two paleontology volunteers stumbled upon one of their massive skulls during a recent expedition to the Hell Creek Formation in Montana, led by Burke Museum Adjunct Curator of Vertebrate Paleontology Greg Wilson. Further digging revealed ribs, vertebrae, and pieces of jaw and pelvis — altogether, about 20 percent of the creature was found.

So far, the excavation has uncovered the right side of the skull, including snout and teeth, and the palaeontologists believe careful removal of the remaining rock surrounding the fossil will expose the remainder of the skull.

Paleontologists prepare to remove T-rex skull

Caption: Paleontologists prepare to remove a Tyrannosaurus rex skull from a fossil dig site in northern Montana and transport it to the Burke Museum at the University of Washington. Credit: Dave DeMar/Burke Museum

Only 14 other intact T. rex skulls have been unearthed, so every new specimen has the potential to shed light on how these iconic dinosaurs grew, what (or whom) they ate, and how they died.

SEE ALSO: First-Ever Fossil Record Facial Tumor Discovered in a Dinosaur

Estimated to have been about the length of a city bus from tail to head, the “Tufts-Love Rex” — nicknamed after the two volunteers who first noticed pieces of its bone poking out of the rocky hillside — is around 85 percent the size of the largest T. rex specimen. Its skull alone is about 4 feet long, and weighs roughly 2,500 pounds with its protective plaster cast.

The size of the skull allowed the team to estimate that the dinosaur was around 15 years old when it died, which is relatively young considering T. rex had a maximum lifespan of 25-30 years.

It took a team effort of more than 45 people, armed with jackhammers, axes, and shovels, to excavate the T. rex this summer, after which it was hauled onto a flatbed truck, driven to Seattle, and unloaded at the Burke Museum.

T. rex skull is removed using a forklift

Caption: UW Burke Museum paleontologists and crew members from Skanska carefully move the 3,500-pound T. rex skull using a forklift. Credit: Burke Museum/University of Washington

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