The saga of the dinosaurs is still being uncovered, and now it has a brand-new long-necked character.
Discovered just north of Arches National Park, the giant plant-eating Mierasaurus has been investigated for years by a team of Utah, Spanish and British paleontologists, and they recently shared their findings with the world in the journal Scientific Reports.
The Mierasaurus is a fascinating and unique piece of the puzzle linking periods of Earth’s ancient history together, helping scientists work toward a better understanding of how and why successful species were wiped out after thriving for millennia, Museum of Moab Director John Foster said.
“It’s important to remember that dinosaurs were animals, and their extinction shouldn’t be held against them,” Foster said. “They were incredibly successful while they were alive. The mere fact that they went extinct isn’t important. Dinosaurs are important because of the 160 million years they were around.”
Cross-continent collaboration was key to fully fleshing out the Mierasaurus’ story, according to Utah Geological Survey Paleontologist James Kirkland. There was no way he or any Utah paleontologist would have made the connection that Spanish paleontologist Rafael Royo-Terres did upon examination of the fossils, he said.
A specialist in sauropods of the European continent, Royo-Terres recognized quickly that Mierasaurus is a descendant of a dinosaur discovered in Teruel, Spain. The Turiasaurus had previously been thought to have gone extinct long before the date of the record at the Utah dig site, so this discovery not only brought a new dinosaur to the world, but also uncovered a cross-continental family tree nobody had recognized before, Kirkland said.
“What we found suggests that this lineage that went extinct in Europe in the late Jurassic period dispersed to North America at some point,” Kirkland said.
The questions now are, how did the Turiasaurus arrive in the New World, and when they reached North America, how were they able to survive?
“As is usual with these kinds of discoveries, it raises almost as many mysteries as it solves,” Kirkland said.
One hypothesis is that the arrival of the Turiasaurus in North America may have coincided with the late Jurassic extinction, perhaps leaving plenty of space for the European dinosaur to thrive and adapt in its new environment.
Happily for paleontologists, there is still plenty of digging to be done in the layer of rock that exposed the Mierasaurus and the recently discovered Moabosaurus, also now recognized as a descendant of the Turiasaurus. Both were found in layers of the Cedar Mountain Formation that scientists now believe exists only in the region of Grand County, according to a Museum of Moab press release.
Thanks to the same salt deposits in the Paradox Formation that created the grandeur of Arches and Canyonlands national parks, the Upper and Lower Yellow Cat Members of the Cedar Mountain Formation preserve the two oldest Cretaceous dinosaur faunas in North America.
“Moab is an epicenter for new discoveries,” Kirkland said.
This year’s two new dinosaurs join more than 20 others identified in the area since the early 1990s. Local enthusiasts, students and scientists who make up the Utah Friends of Paleontology volunteer group have contributed countless hours to digging and excavating in the area since southern Utah became recognized as a treasure trove of prehistoric fossils, Kirkland said.
In the 1960s, Moab Rock Shop owner Lin Ottinger led the late Brigham Young University paleontologist Jim Jensen to fossils in what is now known as the Dalton Wells Quarry. The rockhound and scientist partnership resulted in the original discovery that the Cedar Mesa Formation contained a record of a huge gap in knowledge about the Cretaceous period of Earth’s history.
“It has proven to be the richest and most diverse Lower Cretaceous bonebed in the world,” BYU Paleontologist Rod Sheetz wrote in a letter to Ottinger in November 2009.
Currently, the Utah Geological Survey (UGS) Paleontology Section recognizes 27 distinct dinosaur faunas spanning 165 million years, from 230 to 65 million years ago, according to the UGS web site. Each fauna represents a distinct ecosystem, which range from the very first North American dinosaur-bearing stratum in the Upper Triassic Chinle Formation, through Utah’s real “Jurassic Park” in the Upper Jurassic Morrison Formation, to the uppermost Cretaceous North Horn Formation, which has a lone example of Tyrannosaurus and a record of the extinction of the dinosaurs.
Although the dinosaur record of the Middle Jurassic San Rafael Group is limited to dinosaur tracks, the only real gap in Utah’s extraordinary record is in the transition between the Jurassic and Cretaceous, an interval of up to 25 million years, according to the UGS website. This interval of non-deposition and erosion extends across the entire interior of North America.
The Dalton Wells Quarry was the first indication that Utah might contain fossils that fill the gap, Foster said.
Since the mid-1990s, Kirkland and other enthusiasts and scientists in the UFOP group have pushed for the creation of a state park at the Dalton Wells Quarry site, to offer visitors more in-depth interpretation of the spectacular paleontological record beneath their feet.
“There is a lot of really great work being done in interpretation in the Moab area,” Kirkland said.
Visitors from around the world who are knowledgeable about paleontology already recognize the spectacular opportunity Utah offers for dinosaur enthusiasts, he said.
“China is famous for its dinosaurs, but the Chinese realize that we have 27 non-overlapping faunas – that isn’t found anywhere else in the world,” Kirkland said.
With the sole record of two of the faunas, Grand County is of particular interest to paleontologists, and Kirkland said he hopes to see continued partnership with land managers so that scientists are able to continue making important discoveries like the Mierasaurus.
“They’re not making unspoiled land anymore,” he said. “It is a product that can bring long-term wealth to our state, and continue to build our understanding of the planet we live on.”
Local area continues to be an epicenter for new paleontological finds
Moab is an epicenter for new discoveries.