|
Polyonax
''Polyonax'' (meaning "master over many") was a genus of ceratopsid dinosaur from the late Maastrichtian-age Upper Cretaceous Denver Formation of Colorado, United States. Founded upon poor remains, it is today regarded as a dubious name. History During an 1873 trip through the western US, paleontologist and naturalist Edward Drinker Cope collected some fragmentary dinosaurian material which he soon named as a new genus.Cope, E.D. (1874). Report on the stratigraphy and Pliocene vertebrate paleontology of northern Colorado. ''Bulletin of the U.S. Geological and Geographical Survey of the Territories''. 9:9-28. Catalogued today as AMNH FR 3950, the type material included three dorsal vertebrae, limb bone material, and what are now known to be horn cores, from a subadult individual. Although it was briefly mixed up with hadrosaurs, and even considered to be a possible synonym of ''Trachodon'',Hatcher, J.B. (1902). The genus and species of the Trachodontidae (Hadrosauridae, Cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triceratops
''Triceratops'' ( ; ) is a genus of herbivorous chasmosaurine ceratopsid dinosaur that first appeared during the late Maastrichtian stage of the Late Cretaceous period, about 68 million years ago in what is now North America. It is one of the last-known non-avian dinosaur genera, and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. The name ''Triceratops'', which literally means 'three-horned face', is derived from the Greek words () meaning 'three', () meaning 'horn', and () meaning 'face'. Bearing a large bony frill, three horns on the skull, and a large four-legged body, exhibiting convergent evolution with rhinoceroses and bovines, ''Triceratops'' is one of the most recognizable of all dinosaurs and the most well-known ceratopsid. It was also one of the largest, up to long and in body mass. It shared the landscape with and was most likely preyed upon by '' Tyrannosaurus'', though it is less certain that two adults ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agathaumas
''Agathaumas'' (; "great wonder") is a dubious genus of a large ceratopsid dinosaur that lived in Wyoming during the Late Cretaceous (late Maastrichtian stage, 66 million years ago). The name comes from grc, αγαν - 'much' and - 'wonder'. It is estimated to have been long and weighed , and was seen as the largest land animal known at the time of its discovery. It was the first ceratopsian known to science from more than teeth, though relatively little is known about it. The original specimen consisted only of the animal's hip bones, hip vertebrae and ribs, and because these bones vary little between ceratopsid species, it is usually considered a ''nomen dubium''. It is provisionally considered a synonym of ''Triceratops'', but is difficult to compare to that genus because it is only known from postcranial remains. History The holotype remains of ''Agathaumas'' were first found in 1872 in southwestern Wyoming. They were discovered by Fielding Bradford Meek and Henry Mart ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timeline Of Ceratopsian Research
This timeline of ceratopsian research is a chronological listing of events in the History of paleontology, history of paleontology focused on the ceratopsians, a group of herbivorous marginocephalian dinosaurs that evolved parrot-like beaks, bony frills, and, later, spectacular horns. The first scientifically documented ceratopsian fossils were described by Edward Drinker Cope starting in the :1870s in paleontology, 1870s; however, the remains were poorly preserved and their true nature was not recognized. Over the next several decades, Cope named several such genera and species. Cope's hated Bone Wars, rival, Othniel Charles Marsh, also described ceratopsian remains. In 1887 in paleontology, 1887, Marsh mistook a ''Triceratops'' horn for one belonging to a new species of prehistoric ''Bison''. Marsh also named the eponymous genus ''Ceratops'' in 1888 in paleontology, 1888. The next year, he named the most famous ceratopsian, ''Triceratops horridus''. It was the discovery of ''Tri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ceratopsid
Ceratopsidae (sometimes spelled Ceratopidae) is a family of ceratopsian dinosaurs including ''Triceratops'', '' Centrosaurus'', and '' Styracosaurus''. All known species were quadrupedal herbivores from the Upper Cretaceous. All but one species are known from western North America, which formed the island continent of Laramidia during most of the Late Cretaceous. Ceratopsids are characterized by beaks, rows of shearing teeth in the back of the jaw, elaborate nasal horns, and a thin parietal-squamosal shelf that extends back and up into a frill. The group is divided into two subfamilies— Chasmosaurinae and Centrosaurinae. The chasmosaurines are generally characterized by long, triangular frills and well-developed brow horns. The centrosaurines had well-developed nasal horns or nasal bosses, shorter and more rectangular frills, and elaborate spines on the back of the frill. These horns and frills show remarkable variation and are the principal means by which the various species h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denver Formation
The Denver Formation is a geological formation that is present within the central part of the Denver Basin that underlies the Denver, Colorado, area. It ranges in age from latest Cretaceous ( Maastrichtian) to early Paleocene, and includes sediments that were deposited before, during and after the Cretaceous-Paleogene boundary event.Tweto, O. 1979. Geologic map of Colorado. U.S. Geological Survey, Map G77115. The formation is known for its paleontological resources, including dinosaur remains that are found in the Late Cretaceous part of the formation, and it includes aquifers that are important sources of water for the area. Stratigraphy The Denver Formation rests on the Arapahoe Formation, and its base is marked by the first appearance of tuffaceous sediments. It is overlain by the Dawson Arkose. In 2002 the Denver Formation was included as part of a larger unconformity-bounded unit named the D1 sequence, in order to facilitate basin-wide studies and avoid confusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hadrosaur
Hadrosaurids (), or duck-billed dinosaurs, are members of the ornithischian family Hadrosauridae. This group is known as the duck-billed dinosaurs for the flat duck-bill appearance of the bones in their snouts. The ornithopod family, which includes genera such as ''Edmontosaurus'' and ''Parasaurolophus'', was a common group of herbivores during the Late Cretaceous Period. Hadrosaurids are descendants of the Upper Jurassic/Lower Cretaceous iguanodontian dinosaurs and had a similar body layout. Hadrosaurs were among the most dominant herbivores during the Late Cretaceous in Asia and North America, and during the close of the Cretaceous several lineages dispersed into Europe, Africa, South America and Antarctica. Like other ornithischians, hadrosaurids had a predentary bone and a pubic bone which was positioned backwards in the pelvis. Unlike more primitive iguanodonts, the teeth of hadrosaurids are stacked into complex structures known as dental batteries, which acted as effecti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nomina Dubia
In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a specimen belongs to that group or not. This may happen if the original type series (i. e. holotype, isotype, syntype or paratype) is lost or destroyed. The zoological and botanical codes allow for a new type specimen, or neotype, to be chosen in this case. A name may also be considered a ''nomen dubium'' if its name-bearing type is fragmentary or lacking important diagnostic features (this is often the case for species known only as fossils). To preserve stability of names, the ''International Code of Zoological Nomenclature'' allows a new type specimen, or neotype, to be chosen for a ''nomen dubium'' in this case. 75.5. Replacement of unidentifiable name-bearing type by a neotype. When an author considers that the taxonomic identity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous Dinosaurs Of North America
Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, a concept in econometrics Music * ''Late'' (album), a 2000 album by The 77s * Late!, a pseudonym used by Dave Grohl on his '' Pocketwatch'' album * Late (rapper), an underground rapper from Wolverhampton * "Late" (song), a song by Blue Angel * "Late", a song by Kanye West from ''Late Registration'' Other * Late (Tonga), an uninhabited volcanic island southwest of Vavau in the kingdom of Tonga * "Late" (''The Handmaid's Tale''), a television episode * LaTe, Oy Laivateollisuus Ab, a defunct shipbuilding company * Late may refer to a person who is Dead See also * * * ''Lates ''Lates'' is a genus of freshwater and euryhaline lates perches belonging to the family Latidae. The generic name is also used as a common name, lates, for m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chasmosaurines
Chasmosaurinae is a subfamily of ceratopsid dinosaurs. They were one of the most successful groups of herbivores of their time. Chasmosaurines appeared in the early Campanian, and became extinct, along with all other non-avian dinosaurs, during the Cretaceous–Paleogene extinction event. Broadly, the most distinguishing features of chasmosaurines are prominent brow horns and long frills lacking long spines; centrosaurines generally had short brow horns and relatively shorter frills, and often had long spines projecting from their frills. Chasmosaurines evolved in western North America (Laramidia). They are currently known definitively from rocks in western Canada, the western United States, and northern Mexico. They were highly diverse and among the most species-rich groups of dinosaurs, with new species frequently described. This high diversity of named species is likely a result of the frill. The distinctive shape of the frill with the hornlets on its edges (epoccipitals) make ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neck Frill
A neck frill is the relatively extensive margin seen on the back of the heads of reptiles with either a bony support such as those present on the skulls of dinosaurs of the suborder Marginocephalia or a cartilaginous one as in the frill-necked lizard. In technical terms, the bone-supported frill is composed of an enlarged parietal bone flanked by elongated squamosals and sometimes ringed by epoccipitals, bony knobs that gave the margin a jagged appearance. In the early 1900s, the parietal bone was known among paleontologists as the dermosupraoccipital. The feature is now referred to as the parietosquamosal frill. In some genera, such as ''Triceratops'', '' Pentaceratops'', ''Centrosaurus'' and '' Torosaurus'', this extension is very large. Despite the neck frill predominantly being made of hard bone, some neck frills are made of skin, as is the case with the frill-necked lizard of today that resides in Australia. The use of the neck frill in dinosaurs is uncertain; it may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herbivore
A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthparts adapted to rasping or grinding. Horses and other herbivores have wide flat teeth that are adapted to grinding grass, tree bark, and other tough plant material. A large percentage of herbivores have mutualistic gut flora that help them digest plant matter, which is more difficult to digest than animal prey. This flora is made up of cellulose-digesting protozoans or bacteria. Etymology Herbivore is the anglicized form of a modern Latin coinage, ''herbivora'', cited in Charles Lyell's 1830 '' Principles of Geology''.J.A. Simpson and E.S.C. Weiner, eds. (2000) ''The Oxford English Dictionary'', vol. 8, p. 155. Richard Owen employed the anglicized term in an 1854 work on fossil teeth and skeletons. ''Herbivora'' is derived from Latin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
_grazing_-_20050809.jpg "Click for more on -> Herbivore")