A dinosaur fossil found in Mongolia’s Gobi Desert is rewriting ideas about a little-known group of plant-eating dinosaurs. The discovery reveals the earliest and most complete pachycephalosaur yet.
What Did Scientists Find?
The fossil belongs to a juvenile of a new species, Zavacephale rinpoche, which lived about 108 million years ago. This dinosaur measured roughly one metre long and weighed under six kilograms. Its skull carried a dome made from a single bone, unlike later pachycephalosaurs with domes of two bones. Spikes and nodes decorated the dome and back of the skull.
How Old Is This Dinosaur?
Researchers dated the specimen through growth rings in limb bones, similar to tree rings. The findings place it 15 million years earlier than other pachycephalosaur fossils. This makes Zavacephale the oldest known member of its group.
What Was the Dome Used For?
The dome’s role remains debated. Scientists suggest it was linked to social or mating behaviour. Some believe they head-butted like bighorn sheep to display dominance. Others think it was mainly for showing off. According to palaeontologist Lindsay Zanno, the domes were unlikely used against predators or for temperature control.
What Does This Reveal About Pachycephalosaurs?
The fully formed dome on a young dinosaur shows they engaged in such behaviour before reaching adult size. Larger relatives like Pachycephalosaurus from North America later grew up to 4.3 metres long. Zavacephale adults, however, were likely less than half that length.
Where Did Zavacephale Live?
Its environment was a valley ringed by cliffs, dotted with lakes and home to fish, turtles and early crocodile relatives. The remains of other plant-eating dinosaurs have also been recovered in the same region.
The name Zavacephale comes from the Tibetan word for “origin” and the Latin word for “head”. Until now, most pachycephalosaur fossils were only dome fragments. This left scientists uncertain about their anatomy, arms, digestive systems and the way domes evolved. The new fossil even preserved gastroliths, the stomach stones that helped grind plants.
What Questions Still Remain?
Researchers are still seeking transitional forms to explain how dome-headed dinosaurs developed. They want to understand where pachycephalosaurs fit among other dinosaur groups. As Zanno said, the new fossil closes some gaps but leaves many questions open.
Discover the latest Business News, Sensex, and Nifty updates. Obtain Personal Finance insights, tax queries, and expert opinions on Moneycontrol or download the Moneycontrol App to stay updated!
