Triceratops locks horns with the tyrant king
The three-horned herbivore that fought back
Quick facts
- When
- Late Cretaceous, 68 to 66 million years ago
- Size
- About 9 m long, roughly 10,000 kg
- Frill
- Nearly 1 metre across; one of the largest skulls of any land animal
- Direct combat evidence
- A 1997 fossil horn bitten off, with Tyrannosaurus bite marks
What happened
Triceratops lived in what is now the United States during the very last few million years of the Cretaceous, 68 to 66 million years ago, sharing its world with Tyrannosaurus rex. It carried three horns, a parrot-like beak, and a bony frill that could reach nearly a metre across, giving it one of the largest and most striking skulls of any land animal, on a body about 9 metres long and roughly 10,000 kilograms. The Natural History Museum points to direct proof that these horns saw combat: a partial Triceratops fossil collected in 1997 has a horn bitten clean off, and the bite marks match Tyrannosaurus.
Why it matters
Triceratops is the clearest evidence this timeline has of a real fight between two specific, named dinosaurs, not just an inference from teeth and claws in the abstract. It shows the Late Cretaceous as a genuine predator-prey arms race, playing out in the same place and the same few million years as T. rex.
How we know
The Natural History Museum's record for Triceratops gives its Late Cretaceous age of 68 to 66 million years ago, its size, its horns and frill, and specifically describes the 1997 fossil with a bitten-off horn bearing Tyrannosaurus bite marks.
Sources
- Natural History Museum, London. Triceratops (Natural History Museum Dino Directory) (2024) · Reputable sourcenhm.ac.uk · The domain "nhm.ac.uk" is on our Reputable source registry. · Link is live and its text matches the event's key terms (Jul 2026)
- Is Torosaurus Triceratops? Geometric morphometric evidence of Late Maastrichtian ceratopsid dinosaurs (PLOS ONE, 2013, via PubMed Central) (2013) · Peer-reviewed (author-declared)pmc.ncbi.nlm.nih.gov · Cited as a "journal" source (no stronger domain match). · Link is live and its text matches the event's key terms (Jul 2026)
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