Triceratops

Triceratops is among the most famous dinosaurs, thriving across western North America during the final millions of years before the asteroid impact. Reaching up to 9 metres in length and weighing up to 10 tonnes, it was a colossal herbivore built like an armoured tank. It featured a short nasal horn, two massive brow horns exceeding a metre in length, and a solid bony frill that lacked the large fenestrae seen in other ceratopsids. This solid bone wall likely served as protective armour against bites from Tyrannosaurus rex, as well as a canvas for visual displays and head-to-head intraspecific sparring. Powered by an immense scissor-like shearing beak and constantly replaced dental batteries, Triceratops processed vast amounts of tough vegetation, including palms and cycads, leaving behind a rich fossil record in the Hell Creek Formation.

Unlike almost all other ceratopsids, Triceratops had a solid bony frill completely lacking large openings.

Where and when

Triceratops lived in the Late Cretaceous, from 68 to 66 million years ago (Maastrichtian age). Its remains come from United States and Canada, in the Hell Creek Formation.

The numbers

Length 8.5 m (estimates run from 8 to 9 m). Mass about 7.7 t. Hip height about 2.8 m. That is 5 human-lengths, or 0.76 of a double-decker bus. These are estimates from near-complete skeleton; fields marked estimated by the site are length, mass, hip height.

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