In the summer of 2013 at the Gomer Quarry at Ten Sleep, Washakie County, Wyoming, ripples of excitement ran through the digging team as they uncovered a huge, beautifully preserved theropod skeleton.
After careful excavation, the team found that, hidden within the ground, there were numerous vertebrae, ribs, hips, fore and hind limbs, and most of a skull—including jaw and bearing teeth—all preserved in extraordinarily good condition.
At Ten Sleep, excavations of the 150-million-year-old rocks have revealed an enormous deposit of dinosaur skeletons—documenting a mass mortality event—and have produced some of the most important Jurassic dinosaur discoveries in North America.
Fragmentary bones and isolated teeth of the Allosaurus theropod are common at the Morrison Formation, so there was no mistaking that the newly found skeleton belonged to this well-known predator. However, this skeletal discovery of the Allosaurus is extra-special because it is one of approximately a dozen in museum collections associated with skull material.