![\"Triceratops\u2019](\"https:\/\/cdn.sci.news\/images\/enlarge13\/image_14565e-Triceratops.jpg\")
<\/a><\/p>\nTriceratops\u2019 nasal cavity. Image credit: K. Sakane.<\/p>\n
Horned dinosaurs (Ceratopsia), including the iconic Triceratops, were among the most diverse and successful dinosaur groups of the Late Cretaceous.<\/p>\n
Their skulls rank as some of the most elaborate ever produced by vertebrate evolution, combining the beak, a variety of horns and frills, an expanded nasal region, and a tightly packed dental battery built for processing tough vegetation.<\/p>\n
Because these distinctive features likely underpinned the group\u2019s ecological dominance on land, scientists have long focused on the functions of their cranial structures \u2014 particularly the horns, beak, and frill.<\/p>\n
By contrast, the biological significance of their enlarged nasal region has remained mostly unexamined.<\/p>\n
\u201cI have been working on the evolution of reptilian heads and noses since my Master\u2019s degree,\u201d said Dr. Seishiro Tada, a paleontologist at the University of Tokyo Museum.<\/p>\n
\u201cTriceratops in particular had a very large and unusual nose, and I couldn\u2019t figure out how the organs fit within it even though I remember the basic patterns of reptiles.\u201d<\/p>\n
\u201cThat made me interested in their nasal anatomy and its function and evolution.\u201d<\/p>\n
In the new study, Dr. Tada and his colleagues examined several cranial specimens of Triceratops.<\/p>\n
\u201cEmploying X-ray-based CT-scan data of a Triceratops, as well as knowledge on contemporary reptilian snout morphology, we found some unique characteristics in the nose and provide the first comprehensive hypothesis on the soft-tissue anatomy in horned dinosaurs,\u201d Dr. Tada said.<\/p>\n
\u201cTriceratops had unusual \u2018wiring\u2019 in their noses. In most reptiles, nerves and blood vessels reach the nostrils from the jaw and the nose. But in Triceratops, the skull shape blocks the jaw route, so nerves and vessels take the nasal branch.\u201d<\/p>\n
\u201cEssentially, 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.\u201d<\/p>\n
The researchers also identified a specialized structure in Triceratops\u2019 nose known as a respiratory turbinate, an anatomical feature almost unknown among other dinosaurs but common in their living descendants, birds, as well as in mammals.<\/p>\n
These thin, curled nasal surfaces increase the contact area between air and blood, helping regulate temperature through heat exchange.<\/p>\n
Triceratops probably wasn\u2019t fully warm-blooded, but the scientists think these structures helped keep temperature and moisture levels under control as its large skull would be difficult to cool down otherwise.<\/p>\n
\u201cAlthough we\u2019re not 100% sure that Triceratops had a respiratory turbinate, as most other dinosaurs don\u2019t 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,\u201d Dr. Tada said.<\/p>\n
\u201cThat\u2019s why we conclude they have the respiratory turbinate as birds do.\u201d<\/p>\n
\u201cHorned dinosaurs were the last group to have soft tissues from their heads subject to our kind of investigation, so our research has filled the final piece of that dinosaur-shaped puzzle.\u201d<\/p>\n
\u201cNext, I would like to tackle questions around the anatomy and function of other regions of their skulls like their characteristic frills.\u201d<\/p>\n