HOME
*



picture info

Ornithopods
Ornithopoda () is a clade of ornithischian dinosaurs, called ornithopods (), that started out as small, bipedal cursorial, running grazers and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous world, dominating the North American land. Their major evolutionary advantage was the progressive development of a chewing apparatus that became the most sophisticated ever developed by a non-avian dinosaur, rivaling that of modern mammals such as the domestic cow. They reached their apex of diversity and ecological dominance in the Hadrosauridae, hadrosaurids (colloquially known as 'duck-bills'), before they were wiped out by the Cretaceous–Paleogene extinction event along with all other non-aves, avian dinosaurs. Members are known from all seven continents, though they are generally rare in the Southern Hemisphere. History of research In 1870, Thomas Henry Huxley listed Iguanodontidae (coined by Cope a year earlier) as one of his ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Elasmaria
Elasmaria is a clade of ornithopods known from Cretaceous deposits in South America, Antarctica, and Australia that contains many bipedal ornithopods that were previously considered "hypsilophodonts".Madzia, Daniel; Boyd, Clint A.; Mazuch, Martin (2017). "A basal ornithopod dinosaur from the Cenomanian of the Czech Republic". Journal of Systematic Palaeontology: 1–13. doi:10.1080/14772019.2017.1371258. Classification Calvo ''et al.'' (2007) coined Elasmaria to accommodate '' Macrogryphosaurus'' and ''Talenkauen'', which they recovered as basal iguanodonts distinct from other iguanodontians in having mineralized plates on the ribs. In 2016, a paper describing the genus ''Morrosaurus'' found Elasmaria to be far larger than its initial contents of two taxa, instead containing a variety of ornithopods from the Southern Hemisphere. In 2019, Matthew C. Herne and colleagues redefined Elasmaria as "all taxa closer to ''Macrogryphosaurus gondwanicus'' and ''Talenkauen santacrucensis'' ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Chewing
Chewing or mastication is the process by which food is crushed and ground by teeth. It is the first step of digestion, and it increases the surface area of foods to allow a more efficient break down by enzymes. During the mastication process, the food is positioned by the cheek and tongue between the teeth for grinding. The muscles of mastication move the jaws to bring the teeth into intermittent contact, repeatedly occluding and opening. As chewing continues, the food is made softer and warmer, and the enzymes in saliva begin to break down carbohydrates in the food. After chewing, the food (now called a bolus) is swallowed. It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs. Increasing the number of chews per bite increases relevant gut hormones. Studies suggest that chewing may decrease self-reported hunger and food intake. Chewing gum has been around for many centuries; there is evidence that northern Europeans ch ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya; their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. Dinosaurs are varied from taxonomic, morphological and ecological standpoints. Birds, at over 10,700 living species, are among ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Burianosaurus
''Burianosaurus'' is an extinct genus of ornithopod dinosaur that lived in what is now the Czech Republic (it was found in 2003 near the city of Kutná Hora), being the first validly named dinosaur from that country. The type species, ''B. augustai'', was named in 2017; the genus name honours the Czech palaeoartist Zdeněk Burian, and the species name honours the Czech palaeontologist Josef Augusta. The holotype specimen is a femur discovered in sediments belonging to the Peruc-Korycany Formation in 2003, which was described as possibly belonging to an iguanodont in 2005. Classification When the fossil was first described in 2005, it was said to be most morphologically similar to Early Cretaceous members of Iguanodontidae, as opposed to later taxa such as ''Rhabdodon''. Madzia ''et al.'' (2017), the study which named the genus, ran two phylogenetic analyses to test the relationships of the taxon. The first, based on the matrix of MacDonald ''et al.'' (2012), found it within th ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Changmiania
''Changmiania'' (from the Chinese "changmian", meaning "eternal sleep") is a genus of basal ornithopod dinosaur that lived in what is now China during the Early Cretaceous. It contains a single species, ''Changmiania liaoningensis''. Discovery and naming The taxon is represented by two near-complete articulated skeletons: the holotype specimen, PMOL AD00114; and a referred specimen, PMOL LFV022. These remains were discovered in the Barremian age, 123.2 million years old, Lujiatun Beds of the Yixian Formation by local farmers and partially prepared. They were acquired by the Paleontological Museum of Liaoning at Shenyang, which completed the preparation. No indications were found that the fossils had been tampered with by fossil thieves. The perfect life-like positions of these specimens suggest that they were buried alive, possibly in their own burrows. In 2020, the type species ''Changmiania liaoningensis'' was named and described by Yang Yuqing, Wu Wenhao, Paul-Emile Dieudo ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Convolosaurus
''Convolosaurus'' (, meaning "flocking lizard" after the concentration of juvenile fossils found) is a genus of basal ornithopod dinosaur from the Twin Mountains Formation from Proctor Lake in Comanche County, Texas. The type and only species is ''Convolosaurus marri''. Discovery and naming In May 1985, James "Rusty" Branch at the Proctor Lake in Comanche County, Texas, discovered a dinosaur fossil site which was among the richest from the Lower Cretaceous of North America. The Shuler Museum of Paleontology, part of the Southern Methodist University at Dallas, excavated a large number of specimens on the southeastern bank of the lake, in the Camp Quarry and the North Quarry. The discovery was in 1988 reported in the scientific literature. Remains found were combined into three mounted skeletons displayed at respectively the Proctor Lake US Army Corps of Engineers Office at Proctor (based on specimen SMU 70456), the Perot Museum of Nature and Science, (a composite of specimen ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Gideonmantellia
''Gideonmantellia'' is an extinct genus of basal ornithopod dinosaur known from the Early Cretaceous (Barremian stage) Camarillas Formation of Galve, Province of Teruel, Spain. It contains a single species, ''Gideonmantellia amosanjuanae''. Discovery and naming In 1982, amateur palaeontologist José María Herrero Marzo together with his son Jesús uncovered in a loam pit near Galve, the ''Poyales Barranco Canales'' site, the remains of a small euornithopod. In 1987 from this material by José Luis Sanz a left femur and ilium were described, which he referred to ''Hypsilophodon foxii''. In 1995 José Ignacio Ruiz-Omeñaca realised the find represented a separate taxon, after he had further prepared the bones in 1994 and 1995. Ruiz-Omeñaca continued his studies from 1996, as part of his thesis. In 2001 he published a more detailed and complete description, in 2004 reaffirming that a new species had been discovered. In 2006, in his doctoral thesis he named this ''Gideonmantell ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Weewarrasaurus
''Weewarrasaurus'' is a genus of ornithopod dinosaur from the Late Cretaceous of the Griman Creek Formation near Lightning Ridge, in New South Wales, Australia. The type and only species is ''W. pobeni'', known from the holotype, an isolated preserved in opal, as well as a secondary referred dentary. It is thought to have co-existed with multiple other ornithopods of different sizes and lineages. Discovery and naming The type specimen (the specimen on which the species was first recognised), specimen number LRF 3067, consists of two sections of a jawbone with teeth. It was first discovered in 2013 by miners. They found the specimen in a mine at the Wee Warra geologic locality of the Griman Creek Formation, near the town of Lightning Ridge, New South Wales, Australia during a routine mining run, and it was broken during excavation. Opal dealer Mike Poben, from Adelaide, first recognised it as a fossil, after acquiring it in a bag of rough opals received from the miners. The spe ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland,British Geological Survey. 2011Stratigraphic framework for the Middle Jurassic strata of Great Britain and the adjoining continental shelf: research report RR/11/06 British Geological Survey, Keyworth, Nottingham. the Daohugou Beds in China, the Itat Formation in Russia, and the Isalo III Formation of western Madagascar. Paleogeography During the Middle Jurassic Epoch, Pangaea began to separate into Laurasia and Gondwana, and the Atlantic Ocean formed. Eastern Laurasia was tectonically active as the Cimmerian plate continued to collide with Laurasia's southern coast, completely closing the Paleo-Tethys Ocean. A subduction zone ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


Lexico
Lexico was a dictionary website that provided a collection of English and Spanish dictionaries produced by Oxford University Press (OUP), the publishing house of the University of Oxford. While the dictionary content on Lexico came from OUP, this website was operated by Dictionary.com, whose eponymous website hosts dictionaries by other publishers such as Random House. The website was closed and redirected to Dictionary.com on 26 August 2022. Before the Lexico site was launched, the '' Oxford Dictionary of English'' and ''New Oxford American Dictionary'' were hosted by OUP's own website Oxford Dictionaries Online (ODO), later known as Oxford Living Dictionaries. The dictionaries' definitions have also appeared in Google definition search and the Dictionary application on macOS, among others, licensed through the Oxford Dictionaries API. History In the 2000s, OUP allowed access to content of the ''Compact Oxford English Dictionary of Current English'' on a website called AskOx ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Oxford University Press
Oxford University Press (OUP) is the university press of the University of Oxford. It is the largest university press in the world, and its printing history dates back to the 1480s. Having been officially granted the legal right to print books by decree in 1586, it is the second oldest university press after Cambridge University Press. It is a department of the University of Oxford and is governed by a group of 15 academics known as the Delegates of the Press, who are appointed by the vice-chancellor of the University of Oxford. The Delegates of the Press are led by the Secretary to the Delegates, who serves as OUP's chief executive and as its major representative on other university bodies. Oxford University Press has had a similar governance structure since the 17th century. The press is located on Walton Street, Oxford, opposite Somerville College, in the inner suburb of Jericho. For the last 500 years, OUP has primarily focused on the publication of pedagogical texts and ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

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 ''herba' ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]