Cute, green, and sporting two sprigs of hair on his head, a mischievous baby dinosaur named Dooly is one of the most beloved cartoon characters in South Korea.
So, when researchers from The University of Texas at Austin and the Korean Dinosaur Research Center discovered a new species of baby dinosaur from Korea's Aphae Island, they knew exactly what to call it: Doolysaurus.
"Dooly is one of the very famous, iconic dinosaur characters in Korea. Every generation in Korea knows this character," said Jongyun Jung, a visiting postdoctoral researcher at UT's Jackson School of Geosciences who led the research. "And our specimen is also a juvenile or 'baby', so it's perfect for our dinosaur species name to honor Dooly."
The baby dinosaur is the first new dinosaur species discovered in Korea in 15 years and the first Korean dinosaur fossil found with portions of its skull. The skull bones were revealed when the fossil underwent a scientific micro-CT scan at the University of Texas High-Resolution X-ray Computed Tomography (UTCT) facility.
"When we first found the specimen, we saw some leg bones preserved and some vertebrae," Jung said. "We didn't expect skull parts and so many more bones. There was a fair amount of excitement when we saw what was hidden inside the block."
Research on the dinosaur, whose scientific name is Doolysaurus huhmini, was published in the journal Fossil Record on March 19. The name huhmini, honors the Korean paleontologist Min Huh, who has contributed to the study of Korean dinosaurs over the past 30 years, founded the dinosaur center, and worked with UNESCO to preserve dinosaur fossil sites in Korea. The fossil was discovered in 2023 by co-author Hyemin Jo, a researcher at the dinosaur center.
The dinosaur found by Jo is estimated to be about two years old and was still growing when it died. It's about the size of a turkey, but an adult Doolysaurus may have grown to twice that size. It also may have been covered in a coat of fuzzy filaments.
"I think it would have been pretty cute," said study co-author Julia Clarke, a professor at the Jackson School. "It might have looked a bit like a little lamb."
The fossil is largely encased by hard rock, which can take close to a decade for a trained preparator to excavate by hand. But analysis of the micro-CT scan revealed the full extent of the fossil in a few months. Jong and Clarke then spent more than a year analyzing the anatomy with their coauthors. CT technology has become a critical tool for revealing delicate fossils, such as birds and small non-avian dinosaurs, fossilized in hard rocks, said Clarke.
Doolysaurus lived about 113-94 million years ago during the mid-Cretaceous. Based on its anatomy, the researchers classified it as a thescelosaurid, a type of bipedal dinosaur that lived in East Asia and North America that may have had a fuzzy coat. Researchers could tell it was a juvenile based by observing growth markers on a thin slice of femur bone.
The fossil also contained dozens of gastroliths, pebbles that the baby dinosaur swallowed in life to help with digesting food. The stones suggest that the dinosaur was an omnivore, eating plants, insects and small animals. They are also what prompted the researchers to look closer and scan the fossil. That's because gastroliths are small and light-weight, and the fact that they had remained in place suggested that other parts of the fossil may still be there too.
"A little cluster of stomach stones, with two leg bones sticking out indicates that the animal was not fully pulled apart before it has hit the fossil record," Clarke said. "So, I encouraged [Jung and co-authors Minguk Kim and Hyemin Jo] to visit Texas and the UTCT, to try scanning the fossil."
Kim and Jo are using the CT analysis skills they learned at the Jackson School to study more fossils in Korea. Jung is planning a trip back to Aphae Island to collect more fossils. South Korea is known for fossils of dinosaur tracks, nests, and eggs. While rich in these "trace" fossils, it has a noticeable dearth of actual dinosaur bones.
Jung said it's possible that, like Doolysaurus, they're largely hidden in the rock. He's hopeful that micro-CT technology can lead to even more dinosaurs finds in Korea.
"We're expecting some new dinosaur or other egg fossils to come from Aphae and other small islands," he said.
