page_title: Protoceratops
section_title: Description
hierarchical_section_title: Protoceratops / Description
caption_attribution_description: English: Protoceratops andrewsi
context_page_description: Protoceratops is a genus of sheep-sized herbivorous ceratopsian dinosaur, from the Upper Cretaceous Period of what is now Mongolia. It was a member of the Protoceratopsidae, a group of early horned dinosaurs. Unlike later ceratopsians, however, it was a much smaller creature that lacked well-developed horns and retained some basal traits not seen in later genera.
  Protoceratops had a large neck frill which was likely used as a display site to impress other members of the species. Other hypotheses about its function include protection of the neck and anchoring of jaw muscles, but the fragility of the frill and the poor leverage offered by possible attachment sites here makes these ideas implausible. Described by Walter W. Granger and W.K. Gregory in 1923, Protoceratops was initially believed to be an ancestor of the North American ceratopsians. Researchers currently distinguish two species of Protoceratops, based in part by their respective sizes.
  In the 1920s, Roy Chapman Andrews discovered fossilized eggs in Mongolia that were interpreted as belonging to this dinosaur, but which turned out to be those of Oviraptor.
context_section_description: Protoceratops was a quadrupedal dinosaur that was partially characterized by its distinctive neck frill at the back of its skull. The frill itself contained two large parietal fenestrae (holes in the frill), while its cheeks had large jugal bones. The exact size and shape of the neck frill varied by individual; some specimens had short, compact frills, while others had frills nearly half the length of the skull. The frill consists mostly of the parietal bone and partially of the squamosal. Some researchers, including Peter Dodson attribute the different sizes and shapes of these bones to sexual dimorphism, as well as the age of the specimen, at the time of death.
  Protoceratops was approximately 1.8 meters (5.9 ft) in length and 0.6 meters (2 ft) high at the shoulder. A fully grown adult would have weighed about 82.7 kilograms (182 lb). Smaller specimens are estimated at 23.7 kilograms (52 lb). The large numbers of specimens found in high concentration suggest that Protoceratops lived in herds.</ref>
  Protoceratops was a relatively small dinosaur with a proportionately large skull. Protoceratops appears to have had muscular jaws capable of a powerful bite. These jaws were packed with dozens of teeth, well suited for chewing tough vegetation. The skull consisted of a massive frontal beak, and four pairs of fenestrae (skull openings). The foremost hole, the naris, was considerably smaller than the nostrils seen in later genera. Protoceratops had large orbits (the holes for its eyes), which measured around 50 millimeters in diameter. Behind the eye was a slightly smaller fenestra, known as the "infratemporal fenestra."
caption: Restoration of P. andrewsi
exif: {"Image ImageWidth": "3508", "Image ImageLength": "2480", "Image BitsPerSample": "[8, 8, 8]", "Image PhotometricInterpretation": "2", "Image Orientation": "Horizontal (normal)", "Image SamplesPerPixel": "3", "Image XResolution": "300", "Image YResolution": "300", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CC 2015 (Windows)", "Image DateTime": "2016:12:18 01:48:49", "Image ExifOffset": "236", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "386", "Thumbnail JPEGInterchangeFormatLength": "4227", "EXIF ExifVersion": "0221", "EXIF ColorSpace": "Uncalibrated", "EXIF ExifImageWidth": "3508", "EXIF ExifImageLength": "2480"}