An exciting fossil discovery is shedding new light on the ancient ecosystems of the Lake Powell area.
In March 2023, a field crew from the National Park Service uncovered a trove of rare 180-million-year-old fossils along the shoreline of Lake Powell in Glen Canyon National Recreation Area.
The fossils include the first-ever tritylodontid bonebed found in Utah’s Navajo Sandstone formation. Tritylodontids were early mammal relatives that lived during the Early Jurassic Period shortly after one of the largest mass extinctions in Earth’s history. Their plant-eating teeth and bones provide clues into how mammals recovered and diversified after the extinction event wiped out most species.
“This is one of the most important fossil vertebrate discoveries made in the United States this year,” said NPS paleontologist Andrew Milner. “These fossils are extremely rare in the Navajo Sandstone, so this is a major find for our understanding of Early Jurassic ecosystems.”
The fossil site had been submerged under Lake Powell’s waters, only becoming accessible for a short 120-day window before snowmelt refilled the lake. Working against the clock, the crew was able to excavate hundreds of pounds of rock containing fossils. These will be scanned at the University of Utah before being studied and curated at the St. George Dinosaur Discovery Site with assistance from the Smithsonian Institution.
Eventually, the fossils will be housed at the Prehistoric Museum in Price, Utah as part of the Glen Canyon National Recreation Area museum collections. They will help fill gaps in our knowledge about the fossil species that inhabited the region between 180 to 200 million years ago.
Glen Canyon contains many unexplored fossil sites, making it one of the most important NPS units for paleontological research. The most famous fossils found in the area include numerous dinosaur tracks imprinted in stone.
Milner will present the latest findings at a National Fossil Day event at Zion National Park on October 11. He is also lead author on an upcoming scientific publication describing the fossils and their geologic context. The paper will help demonstrate how dropping lake levels can expose hidden paleontological resources around Lake Powell.
Cover photo courtesy of: NPS