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'''Triceratops''' (Greek: τρι-κέρας-ωψ; "three-horned face"<ref>Liddell, H.G., and R. Scott. Greek-English Lexicon, Abridged Edition. Oxford University Press, Oxford, United Kingdom, 1980</ref>) were two species of ceratopsian (horned) [[dinosaur]], known from fossilized remains found in [[North America]] .  

'''Triceratops''' (Greek: τρι-κέρας-ωψ; "three-horned face"<ref>Liddell, H.G., and R. Scott. Greek-English Lexicon, Abridged Edition. Oxford University Press, Oxford, United Kingdom, 1980</ref>) were two species of ceratopsian (horned) [[dinosaur]], known from fossilized remains found in [[North America]] .  

The mouth was beaked at the fore, leading scientists to speculate that it fed by "nipping" vegetation rather than grazing; the food was then ground down by a battery of simple, yet effective, cheek teeth.  They were assumed to have been browsers of low-lying plants, and judging from fossilized tracks they roamed in small herds.

The mouth was beaked at the fore, leading scientists to speculate that it fed by "nipping" vegetation rather than grazing; the food was then ground down by a battery of simple, yet effective, cheek teeth.  They were assumed to have been browsers of low-lying plants, and judging from fossilized tracks they roamed in small herds.

==Evolutionary claims==

 

===Species===

 

[[File:Cerotopsiansfig037a.jpg|left|200px|thumb|comparison of ''Triceratops'' and ''Torosaurus'' skulls.]]

[[File:Cerotopsiansfig037a.jpg|left|200px|thumb|comparison of ''Triceratops'' and ''Torosaurus'' skulls.]]

Paleontologists once believed there were several species of Triceratops, judging from the large number of [[fossil]] remains, but it is now thought that there were just two, ''T. horridus'' and the larger ''T. prorsus''; the remaining eight animals considered as subspecies or dubious due to being incomplete.  According to evolution, they are descended from ''Psittacosaurus'', a small bipedal ornithopod whose remains were found in central Asia, and from there the ceratopsian line migrated to North America.  ''Triceratops'' has been considered the last of the line, existing just before the end of the [[Cretaceous]] period.<ref>''The Complete Book of Dinosaurs'', by Dougal Dixon, Anness Publishing, 2006</ref>

[[File:Fdt566e4.jpg|left|200px|thumb|American Museum specimen of ''T. horridus''; possible metaplastic bone can be clearly seen in the frill.]]

There has been a recent claim that ''Triceratops'' may not have existed at all.  According to the ''Journal of Vertebrate Paleontology''<ref>http://www.cbsnews.com/8301-501465_162-20012471-501465.html</ref><ref>http://www.vertpaleo.org/publications/index.cfm</ref>, ''Triceratops'' may have been an animal known as [[Torosaurus|''Torosaurus'']], but at a much younger growth stage.  Scientists theorize that ''Triceratops'' - like all reptiles - continued to grow with age; this growth included changes to the frill which - according to the theory  - changed from the deeply-curved solid bone of ''Tricertops'' into the "straight-backed" frill of ''Torosaurus'', a change of which also involved a ''loss'' of bone (the ''fenestræ'', or "windows" in the frill) as a result.  According to Dr. Jack Horner, this process involved "metaplastic" bone which caused a change in the shape of the skull as the animal aged, i.e the backward pointing horns of a baby ''Triceratops'' turning into the forward pointing horns of an adult.<ref>http://www.sciencedaily.com/releases/2009/10/091031002314.htm</ref>

There has been a recent claim that ''Triceratops'' may not have existed at all.  According to the ''Journal of Vertebrate Paleontology''<ref>http://www.cbsnews.com/8301-501465_162-20012471-501465.html</ref><ref>http://www.vertpaleo.org/publications/index.cfm</ref>, ''Triceratops'' may have been an animal known as [[Torosaurus|''Torosaurus'']], but at a much younger growth stage.  Scientists theorize that ''Triceratops'' - like all reptiles - continued to grow with age; this growth included changes to the frill which - according to the theory  - changed from the deeply-curved solid bone of ''Tricertops'' into the "straight-backed" frill of ''Torosaurus'', a change of which also involved a ''loss'' of bone (the ''fenestræ'', or "windows" in the frill) as a result.  According to Dr. Jack Horner, this process involved "metaplastic" bone which caused a change in the shape of the skull as the animal aged, i.e the backward pointing horns of a baby ''Triceratops'' turning into the forward pointing horns of an adult.<ref>http://www.sciencedaily.com/releases/2009/10/091031002314.htm</ref>

According to evolution, they are descended from ''Psittacosaurus'', a small bipedal ornithopod whose remains were found in central Asia, and from there the ceratopsian line migrated to North America.  ''Triceratops'' has been considered the last of the line, existing just before the end of the [[Cretaceous]] period.<ref>''The Complete Book of Dinosaurs'', by Dougal Dixon, Anness Publishing, 2006</ref>

Creationists hold that ''Triceratops'', along with other [[dinosaurs]], were created during the sixth day of [[creation week]], and did not survive the post-flood world.  In support of the [[great flood]] catastrophe, all known ''Triceratops'' fossils - including their trackways - were found in sedimentary (water-laid) rock.

Creationists hold that ''Triceratops'', along with other [[dinosaurs]], were created during the sixth day of [[creation week]], and did not survive the post-flood world.  In support of the [[great flood]] catastrophe, all known ''Triceratops'' fossils - including their trackways - were found in sedimentary (water-laid) rock.

Triceratops is the official state dinosaur of [[Wyoming]].<ref>http://wyoming.gov/general.aspx</ref>

Triceratops is the official state dinosaur of [[Wyoming]].<ref>http://wyoming.gov/general.aspx</ref>