Triceratops from Wikipedia the three in psychopedia. Triceratops is an extinct genus of a vivorous chasmocaurine Saratopsid dinosaur that first appeared during the late Nostrischian states the late Cretaceous period about 68 million years ago and what is now North America. It is one of the last known non-avian dinosaur genera that became extinct in the late Cretaceous Holocene extinction event 65 million years ago. The name Triceratops which literally means three horned face is derived from the Greek words try meaning three garris meaning horn and ups meaning face. Bearing a large bony frill three horns on the skull and a large four-legged body exhibiting convergent evolution with rhinoceros and bovine. Triceratops is one of the most recognizable all dinosaurs and the most well-known Saratopsid. He was also one of the largest up to nine meters or 29 and a half feet long and twelve metric tons or thirteen short tons in weight. His shared the landscape with and was probably preyed upon by tyrannosaurus though it is less certain that two adults did battle in advanceful manner often depicted in museums displays in popular images. The functions of the frills and the three distinctive facial horns on its head had long inspired debate. Traditionally these have been viewed as defensive weapons against predators more recent interpretations find it probably the features were primarily used in species identification courtship and dominance display much like the antlers and horns of modern ungulates. Triceratops was traditionally placed with the short-prild Saratopsids but modern cladistic studies show to be remembered the chasmocernae which usually have long frills. Two species T Heritis and T prorus are considered valid today from the 17 species that have ever been named. Research published in 2010 concluded that the contemporaneous Taurusaurus Saratopsid long regarded as a separate genus represents triceratops in its mature form. This view has been disputed further data is needed to set up a debate. Triceratopsid has been documented by numerous remains collected since the genus was first described in 1889 by American tailing colleges Othneal Charles Marsh. Specimens representing life stages from hatchling to adult have been found as the archetypal Saratopsid triceratopsid were one of the most popular dinosaurs and has been featured in film, postal stamps and many other types of media. Triceratopsid is the official state fossil of South Dakota and the official state's dinosaur Wyoming. In 1942 Charles R. Knight painted a mural incorporating a confrontation between a Tyrannosaurus and a triceratops. In the field museum of natural history for the National Geographic Society established them as enemies in the popular imagination. Paleontologist Bob Bocker said of the Imagine Grub will read between Tyrannosaurus and triceratops. No matchup between predator and prey has ever been more dramatic. It's somehow fitting that those two massive antagonists lived out their coevolutionary belligerence through the last days of the last epic of the age of dinosaurs.