Scientists discover unusual new species of dinosaur that lived underground

Discovery of the burrowing dinosaur, Fauna herzogai, from the middleCretaceous period This period reveals a complex ecosystem where dinosaurs occupied underground spaces. This highlights the diversity and environmental adaptability of dinosaurs, expanding our understanding of their roles in ancient environments.

The Age of Dinosaurs was not just on Earth. A new dinosaur ancestor has been discovered. Thesslosaurus It reveals that these animals spent part of their time in underground burrows. This new Class This adds to our understanding of life during the mid-Cretaceous, both above and below ground.

The new dinosaur Vona [/Foat’NAH/] Herzogay Homo sapiens lived 99 million years ago in what is now Utah. At that time, the area was a large floodplain ecosystem sandwiched between the shores of a vast inland ocean to the east and active volcanoes and mountains to the west. It was a warm, wet, muddy environment with many rivers running through it.

Paleontologists from North Carolina State University The North Carolina Museum of Natural Sciences discovered the fossil—and other specimens of the same species—in the Mosintochit Member of the Cedar Mountain Formation, beginning in 2013. The preservation of these fossils, along with some distinctive features, alerted them to the possibility of digging.

Physical Properties and Drilling Evidence

Vona It was a small-bodied, plant-eating dinosaur about the size of a large dog with a simple body structure. It lacked the bells and whistles of its highly ornate relatives like the horned dinosaurs, armored dinosaurs and crest dinosaurs. But that doesn't mean Vona It was boring.

Vona This animal shares many anatomical features with animals known to dig or burrow, such as large biceps muscles, strong muscle attachment points in the hips and legs, fused bones along the pelvis—which likely aided stability while digging—and hind limbs that were proportionally larger than forelimbs. But that's not the only evidence that this animal spent time underground.

3D printed Fauna skull. Image credit: Lindsay Zano

“The fossil record is biased toward larger animals, primarily because in floodplain environments like Mosintochit, small bones are often scattered on the surface, rotted, or collected before burial and fossilization,” says Haviv Avrahami, a doctoral student at North Carolina State University and digital technician for the new “Dueling Dinosaurs” program at the North Carolina Museum of Natural Sciences. Avrahami is the first author of the paper describing the work.

“but Vona “These bones are often found whole, with many of their bones preserved in their original death position, with the chest down and the forelimbs spread apart, and they are in exceptionally good condition,” Avrahami says. “Had they already been underground in a burrow before death, this type of preservation would have been more likely.”

Lindsay Zanno, an assistant professor at North Carolina State University, head of the paleontology department at the North Carolina Museum of Natural Sciences and corresponding author of the work, agrees.

“Vona “Skeletons are more common in this area than we would expect for a small animal with fragile bones,” says Zanno. “The best explanation for why so many of them have been found, and recovered in small groups of multiple individuals, is that they lived at least part of the time underground. Essentially, Fauna did the hard work for us, by burying herself all over this area.”

Although researchers have not yet been able to identify the subterranean burrows of Vonatunnels and the room of her closest relatives, OryctodromeusTraces of extinct animals have been found in Idaho and Montana. These discoveries support the idea that Vona Burrows are also used.

Vona HerzogayPhoto: Jorge Gonzalez

Cultural and scientific importance of Fauna

Gender name Vona The name comes from the ancient creation story of the Chamorro people, indigenous to Guam and the Mariana Islands in the Pacific Ocean. Fauna and Ponta were sibling explorers who discovered the island and became the land and sky. The species name honors Lisa Herzog, director of paleontology operations at the North Carolina Museum of Natural Sciences, for her invaluable contributions and dedication to the field of paleontology.

“I wanted to honor the indigenous mythology of Guam, where my ancestors are Chamorro people,” says Avrahami. “In the mythology, Fauna became part of the land when she died, and from her body came new life, which for me is associated with petrification, beauty, and creation. Vona It was likely covered in a thin layer of colorful feathers. The species name is Lisa Herzog, who was integral to all this work and discovered one of the most Vona Specimens from several individuals were preserved together in what was probably a burrow.

Vona It is also a distant relative of another famous North Carolina fossil: Willow, The neglected Thesslosaurus The specimen, currently in the museum, is also believed to have adaptations for a semi-fossil — or partially subterranean — lifestyle, according to research published in late 2023 by Zanno and former North Carolina State University researcher David Patton.

“T. Neglecting It was at the end of this lineage – Vona “It's an ancestor of about 35 million years ago,” Avrahami says.

Researchers believe Vona This is key to expanding our understanding of Cretaceous ecosystems.

“Vona “This discovery gives us insight into the third dimension that an animal can occupy by moving underground,” says Avrahami. “It also adds to the richness of the fossil record and expands the known diversity of small-bodied herbivores, which are still poorly understood despite being incredibly integral components of Cretaceous ecosystems.”

“People tend to have a myopic view of dinosaurs that doesn’t keep up with science,” says Zanno. “We now know that dinosaur diversity included a wide range of species, from small tree-flying gliders and nocturnal hunters, to herbivores like sloths, and even animals that lived underground.”

Reference: “A New Subfossil Thessosaurian Dinosaur from the Cenomanian Mosintochit Member of the Cedar Mountain Formation, Utah” by Haviv M. Avrahami, Peter J. Makovicki, Ryan T. Tucker, and Lindsay E. Zanno, July 9, 2024, anatomical record.
DOI: 10.1002/ar.25505