Researchers have uncovered a complex nasal system in Triceratops that may have helped cool its massive head. Using CT scans of fossil skulls, a team from the University of Tokyo revealed intricate networks of nerves, blood vessels, and possible respiratory turbinates. These structures suggest the dinosaur's nose played a role beyond smell, aiding in heat and moisture control.
Horned dinosaurs like Triceratops, part of the Ceratopsia group, featured dramatic skull structures, with Triceratops being one of the most iconic. Despite its fame, the internal anatomy of its skull has remained largely unexplored until now. A team led by Project Research Associate Seishiro Tada from the University of Tokyo analyzed CT scans of fossilized Triceratops skulls, comparing them to the snout morphology of living reptiles such as birds and crocodiles.
The study, published in The Anatomical Record in 2026, highlights unique nasal wiring. In most reptiles, nerves and blood vessels enter the nostrils via the jaw, but Triceratops' skull shape blocked this route, forcing them through the nasal branch instead. "Triceratops had unusual 'wiring' in their noses," Tada explained. "Essentially, Triceratops tissues evolved this way to support its big nose. I came to realize this while piecing together some 3D-printed Triceratops skull pieces like a puzzle."
Further evidence points to respiratory turbinates—thin, scroll-shaped structures that enhance heat exchange between blood and air. While rare in dinosaurs, these are present in birds, dinosaur descendants, and mammals. Triceratops likely was not fully warm-blooded, but such features could have helped manage heat in its large skull and retain moisture. "Although we're not 100% sure Triceratops had a respiratory turbinate, as most other dinosaurs don't have evidence for them, some birds have an attachment base (ridge) for the respiratory turbinate and horned dinosaurs have a similar ridge at the similar location in their nose as well," Tada noted. "That's why we conclude they have the respiratory turbinate as birds do."
Tada's interest stemmed from his master's work on reptilian head evolution. "Triceratops in particular had a very large and unusual nose, and I couldn't figure out how the organs fit within it," he said. The research was funded by the Japan Society for the Promotion of Science. Future studies may examine other skull regions, like the frills.
