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109 Triceratops facts, all checked

Every fact on this site in one place, each linked to its source. Our build checks each one against the source text; see the sources page. Figures that can change carry the date we checked them.

Jump to: The basics | Size (estimates vary) | Horns, frill, beak, teeth and skin | Growing up | Life and behaviour | Triceratops and T. rex | Discovery and species | Hatcher, the Smithsonian’s Triceratops | The Torosaurus debate | Its world | The horned relatives | The extinction | State symbols

The basics

  1. 1 Triceratops means “three-horned face”. Natural History Museum: Triceratops (Dino Directory)
  2. 2 You say it tri-SERRA-tops. Natural History Museum: Triceratops (Dino Directory)
  3. 3 Triceratops was named by Othniel Charles Marsh in 1889. Natural History Museum: Triceratops (Dino Directory)
  4. 4 It lived in the Late Cretaceous, 68 to 66 million years ago. Natural History Museum: Triceratops (Dino Directory)
  5. 5 Its fossils come from the USA, in the Natural History Museum’s directory. Natural History Museum: Triceratops (Dino Directory)
  6. 6 Triceratops was a herbivore: a plant eater. Natural History Museum: Triceratops (Dino Directory)
  7. 7 It walked on four legs. Natural History Museum: Triceratops (Dino Directory)
  8. 8 It was a ceratopsian, a horned dinosaur, in the group called chasmosaurines. Natural History Museum: Triceratops (Dino Directory)
  9. 9 Today scientists recognise two species: Triceratops horridus and Triceratops prorsus. Natural History Museum: Triceratops (Dino Directory) · checked 27 Oct 2026
  10. 10 The first species named, the type species, is Triceratops horridus. Natural History Museum: Triceratops (Dino Directory)
  11. 11 Triceratops is the most abundant dinosaur in Montana’s Hell Creek Formation: more than 50 skulls have been collected there. Scannella, Fowler, Goodwin & Horner (2014), Evolutionary trends in Triceratops, PNAS · checked 27 Oct 2026

Size (estimates vary)

  1. 12 The Natural History Museum gives its length as 9 metres. Natural History Museum: Triceratops (Dino Directory) · checked 27 Oct 2026
  2. 13 The Natural History Museum gives its weight as 10,000 kg (10 tonnes). Natural History Museum: Triceratops (Dino Directory) · checked 27 Oct 2026
  3. 14 The Smithsonian describes it as roughly the same size as an elephant. Smithsonian Magazine: Meet the dinos of “Deep Time”, 2019 · checked 27 Oct 2026
  4. 15 A 2015 study of its teeth describes Triceratops horridus as up to 9 metres in total length. Erickson et al. (2015), Wear biomechanics in the slicing dentition of Triceratops, Science Advances · checked 27 Oct 2026
  5. 16 Its head was huge: about one-third the length of its whole body, according to the Smithsonian. Smithsonian Magazine: Meet the dinos of “Deep Time”, 2019
  6. 17 Adult Triceratops skulls in one growth study were about 2 metres long. The smallest, a baby’s, was 38 cm. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  7. 18 With its three horns, parrot-like beak and a frill nearly a metre across, its skull is one of the largest of any land animal. Natural History Museum: Triceratops (Dino Directory)

Horns, frill, beak, teeth and skin

  1. 19 The fossil horns are only the bony horn cores. In life they were covered in keratin, the stuff of our hair and fingernails, which made them longer and sharper. Natural History Museum: Triceratops (Dino Directory)
  2. 20 Triceratops had two large brow horns and a smaller nose horn. Farke, Wolff & Tanke (2009), Evidence of combat in Triceratops, PLOS ONE
  3. 21 Chasmosaurines like Triceratops tended to have short nose horns and big brow horns. Centrosaurines, like Styracosaurus, had long nose horns. Natural History Museum: Styracosaurus (Dino Directory)
  4. 22 Triceratops had a solid frill, without the big holes seen in some relatives. Longrich & Field (2012), Torosaurus is not Triceratops, PLOS ONE
  5. 23 It had a sharp beak to snip vegetation, and rows of teeth at the back of the jaws that formed shearing surfaces. Natural History Museum: Triceratops (Dino Directory)
  6. 24 The Smithsonian says its beak-like mouth held up to 800 teeth. Smithsonian Magazine: Meet the dinos of “Deep Time”, 2019
  7. 25 Its teeth wore down as it fed into self-sharpening slicing blades, a 2015 study found. Erickson et al. (2015), Wear biomechanics in the slicing dentition of Triceratops, Science Advances
  8. 26 Each tooth was built from five different hard tissues, more than the most complex mammal teeth, which have four. Erickson et al. (2015), Wear biomechanics in the slicing dentition of Triceratops, Science Advances
  9. 27 Skin impressions show Triceratops had large, pebbled scales. Natural History Museum: Triceratops (Dino Directory)
  10. 28 Triceratops wasn’t related to rhinoceroses. They look a bit alike because of convergent evolution: unrelated animals evolving similar shapes. Natural History Museum: Triceratops (Dino Directory)

Growing up

  1. 29 A study of 10 skulls found four growth stages: baby, juvenile, subadult and adult. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  2. 30 Its brow horns changed shape as it grew: straight stubs in babies, curving backwards in juveniles, straightening in subadults, and curving forwards in adults. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  3. 31 A baby’s frill edge was deeply scalloped. Juveniles grew 17 to 19 small triangular bony points along it, which flattened with age and finally merged into the frill in older adults. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  4. 32 Horner and Goodwin suggested these changes let others spot a youngster at a glance, and showed when one was ready to breed. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  5. 33 Skull lengths in that study: the baby about 38 cm (estimated), juveniles 87 to 135 cm, subadults 160 to 200 cm (some estimated) and adults 208 and 225 cm. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  6. 34 The baby’s brow horns stood just 3.5 cm above the eye. In the biggest adult skull they stood 82 cm. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  7. 35 Along the back of the frill, the edge went from scalloped to wavy to smooth as Triceratops grew. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  8. 36 The little nose horn began as a separate bone that later fused on and grew into a nose horn whose shape varied a lot. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  9. 37 For a long time small Triceratops skulls were overlooked: by 2006 only four non-adult specimens had been described. Horner & Goodwin (2006), Major cranial changes during Triceratops ontogeny, Proc. R. Soc. B
  10. 38 As horned dinosaurs grew up, their ornaments developed first, then the skull roof fused, and finally the small bones on the frill, cheeks and beak fused on. Longrich & Field (2012), Torosaurus is not Triceratops, PLOS ONE

Life and behaviour

  1. 39 It probably ate low-growing plants, and could raise its head to reach slightly higher. Natural History Museum: Triceratops (Dino Directory)
  2. 40 The Natural History Museum lists its food as tough palm fronds. Natural History Museum: Triceratops (Dino Directory)
  3. 41 The Smithsonian describes it munching on shrubs and palms. Smithsonian Magazine: Meet the dinos of “Deep Time”, 2019
  4. 42 Many horned dinosaurs lived in herds, but Triceratops remains are usually found alone, which suggests it may have spent much of its life alone. Natural History Museum: Triceratops (Dino Directory)
  5. 43 A 2009 study found Triceratops had more injuries on the squamosal bone of its frill than Centrosaurus did, which fits Triceratops locking horns and the frill acting as a shield. Farke, Wolff & Tanke (2009), Evidence of combat in Triceratops, PLOS ONE
  6. 44 The Natural History Museum says puncture marks on frills show males fought each other, probably to impress females. Natural History Museum: Triceratops (Dino Directory)
  7. 45 The frill might have protected its neck. It could also have helped attract mates, or let Triceratops recognise each other. Natural History Museum: Triceratops (Dino Directory)
  8. 46 It may have used its frill and horns to push through dense plants, or to defend itself while feeding. Natural History Museum: Triceratops (Dino Directory)

Triceratops and T. rex

  1. 47 Triceratops might have used its horns to fend off Tyrannosaurus. Natural History Museum: Triceratops (Dino Directory)
  2. 48 A Triceratops fossil collected in 1997 has a horn bitten off, with bite marks that match Tyrannosaurus. The horn healed, so that Triceratops survived. Natural History Museum: Triceratops (Dino Directory)
  3. 49 Some specimens show Tyrannosaurus bite marks punched through the frill, so it wasn’t always enough protection. Natural History Museum: Triceratops (Dino Directory)
  4. 50 Smithsonian curator Matthew Carrano says some Triceratops skulls bear the telltale hole punches of T. rex teeth. Smithsonian Voices (NMNH): Q&A on the T. rex’s new pose, 2018
  5. 51 T. rex lived at the same time, 68 to 66 million years ago, in the Natural History Museum’s directory. Natural History Museum: Tyrannosaurus (Dino Directory)
  6. 52 Some of the first T. rex bones were named Manospondylus gigas in 1892 by Edward Drinker Cope, who thought they came from a Triceratops-like dinosaur. Natural History Museum: Tyrannosaurus (Dino Directory)

Discovery and species

  1. 53 Marsh’s first find, in 1887, was a pair of horn cores. Natural History Museum: Triceratops (Dino Directory)
  2. 54 Marsh first thought the horn cores came from a giant bison, and called them Bison alticornis. Natural History Museum: Triceratops (Dino Directory)
  3. 55 As more remains turned up, Marsh realised they belonged to a three-horned dinosaur, which he called Triceratops. Natural History Museum: Triceratops (Dino Directory)
  4. 56 As many as 16 species of Triceratops were named over the years, based on differences in skull shape. Scannella, Fowler, Goodwin & Horner (2014), Evolutionary trends in Triceratops, PNAS
  5. 57 A later review recognised only two species, T. horridus and T. prorsus, which differ in things like the length of the brow horns. Scannella, Fowler, Goodwin & Horner (2014), Evolutionary trends in Triceratops, PNAS
  6. 58 The wide variety of skulls probably just means individual Triceratops could look quite different from one another. Natural History Museum: Triceratops (Dino Directory)
  7. 59 In Montana, T. horridus is found lower in the Hell Creek rocks and T. prorsus in the upper third, with in-between forms in the middle. Scannella, Fowler, Goodwin & Horner (2014), Evolutionary trends in Triceratops, PNAS
  8. 60 That pattern suggests Triceratops was slowly changing over time, one species transforming into the next. Scannella, Fowler, Goodwin & Horner (2014), Evolutionary trends in Triceratops, PNAS
  9. 61 Those changes happened over a geologically short time: 1 to 2 million years. Scannella, Fowler, Goodwin & Horner (2014), Evolutionary trends in Triceratops, PNAS

Hatcher, the Smithsonian’s Triceratops

  1. 62 The Smithsonian’s Triceratops “Hatcher” was collected by John B. Hatcher in Niobrara County, Wyoming, in 1890. Smithsonian NMNH collection record: Triceratops horridus (“Hatcher”), USNM PAL500000
  2. 63 In 1905 Hatcher became the world’s first Triceratops to go on exhibit, and for more than 20 years it was the only one on display anywhere. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  3. 64 No complete Triceratops skeleton had been found, so the 1905 mount combined bones from 10 different animals. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  4. 65 The skull was too small for the body, the front legs were different lengths, and the back feet came from a different species with the wrong number of toes. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  5. 66 In 1996 a chunk of Hatcher’s pelvis fell off in front of a visitor. The bones had pyrite disease, which breaks fossils up from the inside. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  6. 67 While it was off display, the Smithsonian made the first 3D scan of an entire dinosaur skeleton. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  7. 68 In 2001 Hatcher went back on show in a more upright pose, worked out with Triceratops experts. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  8. 69 In the Smithsonian’s Deep Time hall, opened in 2019, a cast of Hatcher lies on the floor with a T. rex standing on its ribs. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018 · checked 27 Oct 2026
  9. 70 Was it killed or scavenged? Curator Matthew Carrano says that unless new evidence turns up, the T. rex just as likely scavenged Hatcher after something else killed it. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  10. 71 Hatcher’s ribs are 6 feet (about 1.8 m) long. Smithsonian Voices (NMNH): An elegy for Hatcher the Triceratops, 2018
  11. 72 The original bones are now kept safely in the museum’s collections for research. Smithsonian Magazine: Meet the dinos of “Deep Time”, 2019

The Torosaurus debate

  1. 73 Marsh named Torosaurus in 1891, two years after Triceratops. It also had three horns, but a longer frill with two big holes in it. Smithsonian Magazine: The Torosaurus identity crisis continues, 2012
  2. 74 In 2010 John Scannella and Jack Horner proposed that Torosaurus was really the fully grown form of Triceratops, its frill thinning and opening up holes late in life. Smithsonian Magazine: The Torosaurus identity crisis continues, 2012
  3. 75 Part of their evidence came from bone seen under a microscope: horns of “adult” Triceratops still looked immature, while Torosaurus horns had dense, mature bone. Smithsonian Magazine: New study says Torosaurus = Triceratops, 2010
  4. 76 If they were the same animal, Triceratops would keep its name, because it was named first (1889) and Torosaurus later (1891). Smithsonian Magazine: Relax, Triceratops really did exist, 2010
  5. 77 In 2012 Longrich and Field found both young and mature skulls of both Torosaurus and Triceratops, and concluded Torosaurus is a separate dinosaur. Longrich & Field (2012), Torosaurus is not Triceratops, PLOS ONE
  6. 78 A 2013 study comparing the shape of 28 skulls also found Torosaurus distinct from Triceratops. Maiorino, Farke, Kotsakis & Piras (2013), Is Torosaurus Triceratops?, PLOS ONE
  7. 79 A 2011 study of the puzzling skull Nedoceratops also kept Torosaurus as a separate genus. Farke (2011), Nedoceratops hatcheri, PLOS ONE
  8. 80 Scannella disagreed in 2012, saying “Nothing in this paper falsifies the synonymy” and pointing to bone microstructure and rock layers. Smithsonian Magazine: The Torosaurus identity crisis continues, 2012
  9. 81 The Smithsonian article concluded that one ambiguous skull alone cannot end the debate. Smithsonian Magazine: The Torosaurus identity crisis continues, 2012
  10. 82 The Natural History Museum lists Torosaurus as its own dinosaur, named by Marsh in 1891. Natural History Museum: Torosaurus (Dino Directory) · checked 27 Oct 2026
  11. 83 Torosaurus and Triceratops lived in the same places and times across western North America. Smithsonian Magazine: New study says Torosaurus = Triceratops, 2010

Its world

  1. 84 Triceratops fossils come from rock layers such as the Hell Creek Formation in Montana and the Dakotas and the Lance Formation in Wyoming. Longrich & Field (2012), Torosaurus is not Triceratops, PLOS ONE
  2. 85 Pachycephalosaurus shared its habitat with Tyrannosaurus, Triceratops and Ankylosaurus. Natural History Museum: Pachycephalosaurus (Dino Directory)
  3. 86 The environment was subtropical, with warm, humid air and many flowering plants. Natural History Museum: Pachycephalosaurus (Dino Directory)
  4. 87 Ankylosaurus, the armoured dinosaur with a tail club, also lived 68 to 66 million years ago, and its first bones came from the Hell Creek Formation in 1906. Natural History Museum: Ankylosaurus (Dino Directory)

The horned relatives

  1. 88 Torosaurus: “bull lizard”, about 7.5 m long, with the largest display crest of any ceratopsian. Natural History Museum: Torosaurus (Dino Directory)
  2. 89 Protoceratops: “first horned face”, 1.8 m long, from China and Mongolia, 74 to 70 million years ago. Natural History Museum: Protoceratops (Dino Directory)
  3. 90 One Protoceratops was fossilised while being attacked by Velociraptor. Natural History Museum: Protoceratops (Dino Directory)
  4. 91 Styracosaurus: “spiked lizard”, 5.5 m long, with long spikes around its frill and a huge nose horn. Natural History Museum: Styracosaurus (Dino Directory)
  5. 92 Several Styracosaurus found together in one bone bed suggest they lived and died together. Natural History Museum: Styracosaurus (Dino Directory)
  6. 93 Centrosaurus: “sharp pointed lizard”, 6 m long, with one horn on its snout and spines on its frill. Natural History Museum: Centrosaurus (Dino Directory)
  7. 94 Chasmosaurus: “chasm lizard”, 5 m long, with a small nose horn, blunt brow horns and a long frill with holes. Natural History Museum: Chasmosaurus (Dino Directory)
  8. 95 Pentaceratops: “five-horned face”, 6.8 m long, with a skull almost 3 m long. Natural History Museum: Pentaceratops (Dino Directory)
  9. 96 Psittacosaurus: “parrot lizard”, a ceratopsian 2 m long that walked on 2 or 4 legs, 120 to 100 million years ago in the Early Cretaceous. Natural History Museum: Psittacosaurus (Dino Directory)
  10. 97 Psittacosaurus fossils come from China, Mongolia and Russia. Natural History Museum: Psittacosaurus (Dino Directory)
  11. 98 Torosaurus lived 70 to 66 million years ago, and its fossils come from Canada and the USA. Natural History Museum: Torosaurus (Dino Directory)
  12. 99 Styracosaurus lived 76 to 75 million years ago, in what is now Canada and the USA. Natural History Museum: Styracosaurus (Dino Directory)
  13. 100 Centrosaurus lived 76 to 74 million years ago, in what is now Canada. Natural History Museum: Centrosaurus (Dino Directory)
  14. 101 Chasmosaurus lived 76 to 74 million years ago, in what is now Canada. Natural History Museum: Chasmosaurus (Dino Directory)
  15. 102 Pentaceratops lived 76 to 74 million years ago, in what is now the USA. Natural History Museum: Pentaceratops (Dino Directory)
  16. 103 Edmontosaurus, a duck-billed dinosaur, had a beak and about 1,000 grinding cheek teeth. Natural History Museum: Edmontosaurus (Dino Directory)

The extinction

  1. 104 Sixty-six million years ago an asteroid hit Earth and ended the age of the dinosaurs. Natural History Museum: How an asteroid ended the age of the dinosaurs
  2. 105 About 75% of all animals died out. Natural History Museum: How an asteroid ended the age of the dinosaurs
  3. 106 The asteroid was probably 10 to 15 km wide and made the Chicxulub crater, 150 km across, centred on Mexico’s Yucatán Peninsula. Natural History Museum: How an asteroid ended the age of the dinosaurs
  4. 107 Triceratops was among the last non-bird dinosaurs: its teeth studied in 2015 are about 66 million years old. Erickson et al. (2015), Wear biomechanics in the slicing dentition of Triceratops, Science Advances

State symbols

  1. 108 Triceratops is the official state fossil of South Dakota. South Dakota Codified Law 1-6-16.1: State fossil
  2. 109 Triceratops is Wyoming’s state dinosaur, adopted on 18 March 1994. State of Wyoming: Wyoming facts and symbols