Meet the dinosaurs of Grand Staircase–Escalante, a national monument President Trump is threatening with extinction

Cuts to Utah’s national monument could threaten access to a ‘treasure trove’ of dinosaur fossils

Grand Staircase–Escalante National Monument | Photo: Tim Peterson, Illustrations: Lucy Livesay

On Monday, President Trump will travel to Utah to announce significant cuts to two of the state’s most remarkable national monuments, Grand Staircase–Escalante and Bears Ears. It will be the largest rollback of protections to public lands in history and could open what one paleontologist called the “last great, largely unexplored dinosaur boneyard in the lower 48 states” to coal mining and other energy development.

Today, Grand Staircase–Escalante National Monument is 1.9 million acres of spectacular desert landscapes, winding slot canyons and high plateaus, natural bridges and trickling ephemeral streams. It was the last place in the continental U.S. to be mapped and remains an unspoiled natural frontier drawing outdoor enthusiasts and scientific experts in search of adventure and exploration from across the country. The monument forms the economic backbone of local communities in southern Utah, attracting new businesses and visitors to this rural stretch of the Southwest.

But 76 million years ago, this corner of southwestern Utah looked entirely different. Instead of desert, Grand Staircase–Escalante was home to a lush, tropical rainforest, where abundant plants supported an ecosystem of prehistoric giants. The monument is now known as the ‘Shangri-La of dinosaurs.’

Around 90 million years ago, during the Late Cretaceous period, rising seas inundated the middle of the country, splitting North America into two continents: Laramidia to the west and Appalachia to the east. All records of Laramidia, known as the “lost continent,” are buried under layers of rock and soil in the Western states. Paleontologists have only uncovered fossils from Laramidia in a handful of exceptional and heavily-eroded landscapes — like Grand Staircase–Escalante National Monument — but what they have unearthed has challenged long-standing assumptions about dinosaur evolution and revealed remarkable new species.

So far, paleontologists have found 25 unique species of dinosaurs in Grand Staircase–Escalante. The Kaiparowits formation and its predecessor, the Wahweap formation, have become a practical “treasure trove” of fossils revealing never-before-seen tropical plants, turtles, crocodiles, and dinosaurs. Laramidia, a continent one-fifth the size of Africa, was home to 15 to 20 rhinoceros- to elephant-sized species of dinosaurs likely thriving off the abundant resources of the tropical ecosystem — Grand Staircase–Escalante was home to many of them.

Meet the dinosaurs of Grand Staircase–Escalante National Monument.

Kosmoceratops richardsoni

Age: ~76 million years ago
Formation: Kaiparowits
Name: ornamented horned face (nickname: the “horny-est dinosaur ever”)
Size: 15 feet long, with a massive skull measuring at nearly 6 feet
Diet: Herbivore

Fun facts: Paleontologists think that Kosmoceratops 13-horned frill was used for intimidation or for attracting mates, not defense. According to paleontologist Scott Sampson, “The sideways-oriented horns offer another means to lock heads and engage in contests of dominance.” Whatever their purpose, it’s easy to see how Kosmoceratops earned it’s nickname — “horny-est dinosaur ever.”

Nasutoceratops titusi

Age: ~76 million years ago
Formation: Kaiparowits
Name: big-nose horned face
Size: 15 feet long
Diet: Herbivore

Fun facts: Both Nasutoceratops and Kosmoceratops are part of the “ceratopsid” family. All ceratopsids display pronounced nose regions, but Nasutoceratops’ oversized nose takes it to a new level. According to Sampson, “The jumbo-sized schnoz of Nasutoceratops likely had nothing to do with a heightened sense of smell — since olfactory receptors occur further back in the head, adjacent to the brain — and the function of this bizarre feature remains uncertain.”

Utahceratops gettyi

Age: ~76 million years ago
Formation: Kaiparowits
Name: Utahceratops is named for its home state — Utah!
Size: 18–22 feet long, with a massive 7 foot skull
Diet: Herbivore

Fun facts: Utahceratops’ mouth contains hundreds of rows of column-like teeth, creating a “dental battery” used for slicing up tough plants. Because of the size of its massive 7 foot skull, Utahceratops’ horned frill at the top of its head is hollow to minimize its weight.

Diabloceratops eatoni

Age: ~80 million years ago
Formation: Wahweap
Name: devil, (nickname: the “Last Chance Ceratopsian”)
Size: 18 feet long
Diet: Herbivore

Fun facts: Diabloceratops’ is named for its devilish horns, but its nickname — the “Last Chance Ceratopsian” — comes from the Last Chance Stream where it was found. First discovered in 1998, Diabloceratops is the oldest-known member of the centrosaurine ceratopsian family and the first unearthed south of Montana.

Macharioceratops cronusi

Age: ~77 million years ago
Formation: Kaiparowits
Name: bent sword face
Size: 20–26 feet long
Diet: Herbivore

Fun facts: Macharioceratops’ unique hook-like horns earned it the name ‘bent sword face,’ but their purpose remains a mystery to scientist. Ohio University paleontologist Erik Lund says, “[It’s] a unique morphology unto itself, but there is also a groove on the big spikes, which is a characteristic not ever seen before in horned dinosaurs.” While it’s possible the hooks were a mating display feature or used for intimidation, their exact use is unknown.

Teratophoneus curriei

Age: ~76 million years ago
Formation: Kaiparowits
Name: monstrous murderer
Size: 12 feet tall
Diet: Carnivore

Fun facts: Teratophoneus is the most complete Tyrannosaur fossil in the Southwest. So far, 80 percent of its skeleton has been unearthed, remarkably preserved in the position it died in. Despite its name, Teratophoneus was not nearly as monstrous as its relative Tyrannosaurus, the most famous member of the Tyrannosaur group. Based on the skeleton uncovered in Grand Staircase–Escalante, Teratophoneus was only about one-tenth of the size of the mighty Tyrannosaurus.

Lythronax argestes

Age: ~80 million years ago
Formation: Wahweap
Name: king of gore
Size: 24 feet long
Diet: Carnivore

Fun facts: At approximately 80 million years old, Lythronax is the oldest known tyrannosaur. “Despite being the oldest known tyrannosaurid, it’s by no means a primitive member of the group,” says Corwin Sullivan of the Institute of Vertebrate Palaeontology and Palaeoanthropology in Beijing, “[That] tells us two interesting things: that tyrannosaurids started their evolutionary radiation sooner than we thought, and that a fair bit of their early record is still missing.”

Gryposaurus monumentensis

Age: ~76 million years ago
Formation: Kaiparowits
Name: hooked beaked lizard
Size: 40 feet long
Diet: Herbivore

Fun facts: 76 million years ago, Gryposaurus was the largest known dinosaur in Utah, surpassing local tyrannosaurs. In fact, Gryposaurus was so large that Sampson has referred to it as the “Arnold Schwarznegger of duck-billed dinosaurs.” The second half of Gryposaurus’ name, monumentensis, is named for Grand Staircase–Escalante National Monument, where many monumental paleontological discoveries have been unearthed.

Parasaurolophus cyrtocristatus

Age: ~75 million years ago
Formation: Kaiparowits
Name: near crested lizard
Size: 30 feet tall
Diet: Herbivore

Fun facts: Paleontologists believe that Parasaurolophus’ strange, tubular crest was likely used to attract mates. Fossils indicate that the crests of Parasaurolophus males were bigger than female crests. As Alan Titus, the Bureau of Land Management paleontologist at Grand Staircase–Escalante, says, “It’s about looking good and showing off.”

Talos sampsoni

Age: ~76 million years ago
Formation: Kaiparowits
Name: Talos, which means talon in Greek, is named for a winged figure with lightning-fast speed from Greek mythology
Size: 6 feet long, 3 feet tall
Diet: Omnivore

Fun facts: The extremely rare Talos remains unearthed in Grand Staircase–Escalante gave paleontologists an unlikely window into Talos’ behavior. Because of a severe injury Lindsay Zanno, a paleontologist at The Field Museum of Natural History in Chicago, believes the dinosaur was likely “doing something dangerous, something high risk.” According to Zanno, “[The talon] was either used to hunt prey, or it was used in combat with other members of the species, which is something other modern birds do.” Paleontologists even suggest the talon may have been used as a puncture device, possibly to climb large prey or pin down smaller animals.


Dinosaurs went extinct only 10 million years after the ‘Shangri-La of dinosaurs’ was at its height. But now, 65 million years after their death, the dinosaurs of Grand Staircase–Escalante face a new threat. Next week, President Trump will travel to Utah to announce extreme cuts to Grand Staircase–Escalante National Monument, in addition to the Bears Ears National Monument. The president’s unprecedented conservation rollback comes at the behest of Utah politicians that see only one future for the monument: coal mining.

The Kaiparowits Plateau, home to most of the monument’s paleontological dig sites, overlays a 500,000 acre coal seam within the boundaries of the monument. The Utah Geological Survey estimates Grand Staircase–Escalante contains between $212 billion and $312 billion of coal reserves.

Utah Senator Orrin Hatch confirmed the administration’s priorities, saying President Trump plans to modify the boundaries of Grand Staircase–Escalante to open up access to coal mining in the Kaiparowits Plateau. “I’d like to see us have access to that,” Senator Hatch told the Utah Senate.

Scott Sampson, whose paleontological work has been central to the exploration of Grand Staircase, told the Los Angeles Times, “My fear is that opening up the monument to energy extraction will threaten our ability to uncover the secrets that we know must still be buried in the monument.”

Only 6 percent of Grand Staircase–Escalante has been surveyed by paleontologists. Imagine the breath of knowledge, clues to the “lost continent” of Laramidia, that will be lost if access to this living laboratory is cut off.


Illustrations by Lucy Livesay, Center for Western Priorities

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