Dinosaur Hall - Ceratopsians
Ceratopsians are the Rhinos of the dinosaur worldâ€”large, plant eating and
horned. All ceratopsians have a â€˜beakâ€™ and at least the beginning of a
frill. Later forms also had the well-known horns.
Psittacosaurus means the â€œparrot-lizardâ€ because of
the shape of its beak. Although they donâ€™t look much alike,
Psittacosaurus was an ancestor of the four-footed horned dinosaurs such
as Triceratops. Psittacosaurus lived 110 million years
ago during the Early Cretaceous, while Triceratops was abundant in
the Late Cretaceous, 65 million years ago.
Protoceratops was a small primitive ceratopsian.
Protoceratops and its relatives had a short frill, teeth with single
roots, little if any nose horn and no brow horns. Protoceratops
is one of the most common Late Cretaceous dinosaurs in Asia.
Zuniceratops is a ceratopsian notable for many firsts. It is
the first North American ceratopsian, the first ceratopsian with doubled
rooted teeth and the first ceratopsian with brow horns. Expeditions
sponsored by the Arizona Museum of Natural History, now the Arizona Museum
of Natural History, discovered Zuniceratops in Cretaceous sediments
90 million years old near the Arizona â€“ New Mexico border.
Triceratops was one of the last dinosaurs to roam the Western
Interior and perhaps the most abundant dinosaur of its time, 65 million
years ago. Although abundant, Triceratops apparently did not
range south of what is today mid-Colorado. Triceratops stood up to 10
feet tall, measured 30 feet long, and weighed more than 6 tons (12,000
pounds). Triceratops used its long, sharp horns for defense
against large meat eating predators such as Tyrannosaurus. This
specimen is an adolescent, not yet fully mature.
Pentaceratops means â€œfive horned faced,â€ because bones in the
â€œcheekâ€ region have developed into a fourth and fifth pair of horns. To
date, Pentaceratops are only known from Cretaceous sediments of
northwest New Mexico, about 75 million years ago.