A rare glimpse into the life of a teenage dinosaur

Dr Ryan Tucker from Stellenbosch University’s Department of Earth Sciences is part of an international team of scientists that unearthed the “teenage” fossil of a rare dinosaur group in Mongolia’s Gobi Desert, the university said in a statement. 

The fossil represents a new species of pachycephalosaur and is both the oldest and most complete skeleton of this dinosaur family found to date.

According to a media statement by North Carolina State University, the “teenage” pachycephalosaur may provide answers to lingering questions about the dinosaur group.

The new research was published on Wednesday, September 17, in the journal Nature.

“Pachycephalosaurs are iconic dinosaurs, but they are also rare and mysterious,” said Lindsay Zanno, associate research professor at North Carolina State University, head of paleontology at the North Carolina Museum of Natural Sciences, and corresponding author of the work.

The specimen was discovered in the Khuren Dukh locality of the Eastern Gobi Basin by Tsogtbaatar Chinzorig from the Mongolian Academy of Sciences, who is the lead author of the paper and currently a research assistant at NC State.

The new species is called Zavacephale rinpoche, which is the combination of zava, meaning “root” or “origin” in Tibetan, and cephal, meaning “head” in Latin. The specific name, “rinpoche,” or “precious one” in Tibetan, refers to the domed skull discovered exposed on a cliff like a cabochon jewel.

“Pachycephalosaurs are all about the bling, but we can’t use flashy signaling structures alone to figure out what species they belong to or what growth stage they are in because some cranial ornamentation changes as animals mature,” Ms Zanno said.

“We age dinosaurs by looking at growth rings in bones, but most pachycephalosaur skeletons are just isolated, fragmentary skulls,” Ms Zanno added.

Pachycephalosaurs are famous for their large domed skulls and are often depicted using those domes to duel in epic headbutting contests. 

Ms Zanno said this specimen is a “once-in-a-lifetime” discovery. 

“It is remarkable for being the oldest definitive pachycephalosaur, pushing back the fossil record of this group by at least 15 million years, but also because of how complete and well-preserved it is,” Ms Zanno said, adding that Z. rinpoche gives them an unprecedented glimpse into the anatomy and biology of pachycephalosaurs, including what their hands looked like and that they used stomach stones to grind food.