A newly found ancestor of Thescelosaurus reveals proof that these animals spent at the very least a part of their time in underground burrows.
The brand new species contributes to a fuller understanding of life in the course of the mid-Cretaceous—each above and beneath floor.
The brand new dinosaur, Fona [/Foat’NAH/] herzogae lived 99 million years in the past in what’s now Utah. At the moment, the realm was a big floodplain ecosystem sandwiched between the shores of a large inland ocean to the east and lively volcanoes and mountains to the west. It was a heat, moist, muddy atmosphere with quite a few rivers operating by it.
Paleontologists from North Carolina State College and the North Carolina Museum of Pure Sciences unearthed the fossil—and different specimens from the identical species—within the Mussentuchit Member of the Cedar Mountain Formation, starting in 2013. The preservation of those fossils, together with some distinguishing options, alerted them to the potential of burrowing.
Fona was a small-bodied, plant-eating dinosaur concerning the measurement of a big canine with a easy physique plan. It lacks the bells and whistles that characterize its extremely ornamented kin corresponding to horned dinosaurs, armored dinosaurs, and crested dinosaurs. However that doesn’t imply Fona was boring.
Fona shares a number of anatomical options with animals identified for digging or burrowing, corresponding to giant bicep muscle tissue, robust muscle attachment factors on the hips and legs, fused bones alongside the pelvis—probably to assist with stability whereas digging—and hindlimbs which might be proportionally bigger than the forelimbs. However that isn’t the one proof that this animal frolicked underground.
“The bias within the fossil document is towards greater animals, primarily as a result of in floodplain environments just like the Mussentuchit, small bones on the floor will typically scatter, rot away, or change into scavenged earlier than burial and fossilization,” says Haviv Avrahami, a PhD scholar at NC State and digital technician for the brand new Dueling Dinosaurs program on the North Carolina Museum of Pure Sciences. Avrahami is first writer of the paper describing the work.
“However Fona is commonly discovered full, with lots of its bones preserved within the authentic dying pose, chest down with splayed forelimbs, and in exceptionally good situation,” Avrahami says. “If it had already been underground in a burrow earlier than dying, it could have made one of these preservation extra probably.”
Lindsay Zanno, affiliate analysis professor at NC State, head of paleontology on the North Carolina Museum of Pure Sciences, and corresponding writer of the work, agrees.
“Fona skeletons are far more frequent on this space than we’d predict for a small animal with fragile bones,” Zanno says. “The very best clarification for why we discover so lots of them, and get well them in small bundles of a number of people, is that they have been residing at the very least a part of the time underground. Primarily, Fona did the exhausting work for us, by burying itself throughout this space.”
Though the researchers have but to establish the subterranean burrows of Fona, the tunnels and chamber of its closest relative, Oryctodromeus, have been present in Idaho and Montana. These finds assist the concept that Fona additionally used burrows.
The genus identify Fona comes from the ancestral creation story of the Chamorro individuals, who’re the indigenous populations of Guam and the Pacific Mariana Islands. Fo’na and Pontan have been brother and sister explorers who found the island and have become the land and sky. The species identify honors Lisa Herzog, the paleontology operations supervisor on the North Carolina Museum of Pure Sciences, for her invaluable contributions and dedication to the sector of paleontology.
“I needed to honor the indigenous mythology of Guam, which is the place my Chamorro ancestors are from,” Avrahami says. “Within the delusion, Fo’na turned a part of the land when she died, and from her physique sprung forth new life, which to me, ties into fossilization, magnificence, and creation. Fona was most certainly coated in a downy coat of colourful feathers. The species identify is for Lisa Herzog, who has been integral to all this work and found one of the distinctive Fona specimens of a number of people preserved collectively in what was probably a burrow.”
Fona can be a distant relative of one other well-known North Carolina fossil: Willo, a Thescelosaurus neglectus specimen at the moment housed on the museum and likewise thought to have diversifications for a semifossorial—or partially underground—way of life, analysis that was published late in 2023 by Zanno and former NC State postdoctoral researcher David Button.
“T. neglectus was on the tail finish of this lineage—Fona is its ancestor from about 35 million years prior,” Avrahami says.
The researchers imagine Fona is essential to increasing our understanding of Cretaceous ecosystems.
“Fona provides us perception into the third dimension an animal can occupy by transferring underground,” says Avrahami. “It provides to the richness of the fossil document and expands the identified variety of small-bodied herbivores, which stay poorly understood regardless of being extremely integral elements of Cretaceous ecosystems.”
“Folks are likely to have a myopic view of dinosaurs that hasn’t stored up with the science,” Zanno says. “We now know that dinosaur variety ran the gamut from tiny arboreal gliders and nocturnal hunters, to sloth-like grazers, and sure, even subterranean shelterers.”
The work seems in The Anatomical Record.
Extra researchers from the College of Minnesota and Stellenbosch College additionally contributed to the work.
Supply: NC State
