The 110-million-year-old Mongolian dinosaur Zavacephale was identified as the oldest pachycephalosaur yet discovered and already possessed a domed skull, 14 million years earlier than paleontologists had thought pachycephalosaurs evolved that feature.
Notes on verification
Confirmed by peer-reviewed Nature publication and corroborated by multiple independent science news outlets (Scientific American, NBC News, ScienceAlert). [tier=gold indep_score=0.9 clusters=4 claim_tier=notable]
Sources
- The Top Ten Dinosaur Discoveries of 2025, From Preserved Blood ... (seed:science_and_space)
- https://www.nature.com/articles/s41586-025-09213-6 (corroboration)
- https://www.scientificamerican.com/article/oldest-known-pachycephalosaur-fossil-discovered-in-mongolia/ (corroboration)
- https://www.sciencealert.com/stunningly-complete-dome-headed-dinosaur-emerges-from-the-sands-of-mongolia (corroboration)
- https://www.nbcnews.com/world/asia/oldest-complete-fossil-dome-headed-dinosaur-found-mongolia-rcna232070 (corroboration)