Dinosaurs A to Z
Ceratopsia

Protoceratops andrewsi PROH-toh-SAIR-uh-tops

"First horned face"

Protoceratops silhouette
You 1.8 m (5.9 ft) tall
Protoceratops 1.8 m (5.9 ft) long
as long as 2 people standing fingertip to fingertip
silhouette · Gareth Monger (CC-BY) via PhyloPic
Length
1.8 m (5.9 ft) — About 1.8 m long, ~80 kg — sheep-sized early ceratopsian.
Period
Late Cretaceous (75–71 Mya)
Place
Asia · Mongolia
Food
Herbivore — Tough desert plants — Protoceratops lived in arid environments full of sand dunes.
Clade
Ceratopsia Dinosauria Ornithischia Cerapoda Marginocephalia Beaked, frilled herbivores. Most famous: Triceratops.

A small, frilled plant-eater from the Gobi, found by a photographer at the Flaming Cliffs.

Protoceratops was a small ceratopsian without big horns — just a small bony frill behind the skull and a parrot-like beak. Hundreds of skeletons have been found in Mongolia, including the famous ‘Fighting Dinosaurs’ fossil where a Protoceratops is locked in combat with a Velociraptor, both buried by a collapsing sand dune.

More about Protoceratops

Discovery

Named by described in 1923 (genus placed in family Protoceratopsidae by Granger and Gregory) · 1923 · the Flaming Cliffs of the Djadokhta Formation, Gobi Desert, Mongolia

On 2 September 1922, during the American Museum of Natural History's Third Central Asiatic Expedition, photographer James B. Shackelford spotted a partial juvenile skull in reddish sandstones at the Flaming Cliffs. It became the holotype (AMNH 6251) and was first identified as reptilian by paleontologist Walter W. Granger.

What was the sail-like structure on its tail for?
Protoceratops had a long tail with an enigmatic sail-like structure. The text says it may have been used for display, swimming, or metabolic reasons, so its purpose is uncertain and not settled.
Did Protoceratops give rise to the big horned dinosaurs?
Its place in ceratopsianA horned, frilled plant-eater like Triceratops. evolution has been debated for decades. Colbert in 1951 saw it as a key ancestor of large ceratopsids, while Maryanska and Osmolska in 1975 argued protoceratopsids probably neither descended from psittacosaurids nor gave rise to the advanced ceratopsids. The text also notes that P. andrewsi may have evolved into Bagaceratops through anagenesis.

What we know

  • Small bony frill, parrot beak, no horns.
  • Found in Mongolia in vast numbers — hundreds of skeletons known.
  • The 'Fighting Dinosaurs' specimen preserves combat with a Velociraptor.
  • Eggs and nests found nearby, mistakenly attributed to Oviraptor in 1924.

What we guess

  • Whether the small frill was for defense, display, or muscle attachment for chewing.
  • Whether the legend of the griffin came from ancient peoples finding Protoceratops bones near gold deposits.
  • Whether the eggs Roy Chapman Andrews collected in the 1920s belonged to Protoceratops or Oviraptor (later DNA-style analyses say both species used the area).