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Ornithoscelida
Ornithoscelida () is a proposed clade that includes various major groupings of dinosaurs. An order Ornithoscelida was originally proposed by Thomas Henry Huxley but later abandoned in favor of Harry Govier Seeley's division of Dinosauria into Saurischia and Ornithischia. The term was revived in 2017 after a new cladistic analysis by Baron ''et al''. Huxley's concept Thomas Henry Huxley originally defined the term in an 1869 lecture as a group comprising two subgroups: the large and heavy-set Dinosauria and the newly discovered ''Compsognathus'', which he placed in a new grouping Compsognatha. The former were defined by their shorter cervical vertebrae, and the femur length exceeding tibia length, and the latter with longer cervical vertebrae, and the femur length shorter than tibia length. He noted that the characteristics of their bones showed many features akin to birds. The dinosaurs Huxley had divided into three families: * Megalosauridae: ''Teratosaurus'', ''Palaeosaurus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saurischia
Saurischia ( , meaning "reptile-hipped" from the Greek ' () meaning 'lizard' and ' () meaning 'hip joint') is one of the two basic divisions of dinosaurs (the other being Ornithischia), classified by their hip structure. Saurischia and Ornithischia were originally called orders by Harry Seeley in 1888 though today most paleontologists classify Saurischia as an unranked clade rather than an order.Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). (2004). ''The Dinosauria. 2nd edition''. University of California Press, Berkeley. 833 pp. Description All carnivorous dinosaurs (certain types of theropods) are traditionally classified as saurischians, as are all of the birds and one of the two primary lineages of herbivorous dinosaurs, the sauropodomorphs. At the end of the Cretaceous Period, all saurischians except the birds became extinct in the course of the Cretaceous–Paleogene extinction event. Birds, as direct descendants of one group of theropod dinosaurs, are a sub-clad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithischia
Ornithischia () is an extinct order of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name ''Ornithischia'', or "bird-hipped", reflects this similarity and is derived from the Greek stem ' (), meaning "of a bird", and ' (), plural ', meaning "hip joint". However, birds are only distantly related to this group as birds are theropod dinosaurs. Ornithischians with well known anatomical adaptations include the ceratopsians or "horn-faced" dinosaurs (e.g. ''Triceratops''), the pachycephalosaurs or "thick-headed" dinosaurs, the armored dinosaurs (Thyreophora) such as stegosaurs and ankylosaurs, and the ornithopods. There is strong evidence that certain groups of ornithischians lived in herds, often segregated by age group, with juveniles forming their own flocks separate from adults. Some were at least partially covered in filamentous (hair- or feather- like) pelts, and there is much debate over whether these filaments fou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theropoda
Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally carnivorous, although a number of theropod groups evolved to become herbivores and omnivores. Theropods first appeared during the Carnian age of the late Triassic Period (geology), period 231.4 million years ago (Year#SI prefix multipliers, Ma) and included all the large terrestrial carnivores from the Early Jurassic until at least the close of the Cretaceous, about 66 Ma. In the Jurassic, birds evolved from small specialized coelurosaurian theropods, and are today represented by about 10,500 living species. Biology Diet and teeth Theropods exhibit a wide range of diets, from insectivores to herbivores and carnivores. Strict carnivory has always been considered the ancestral diet for theropods as a group, and a wider variety of di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compsognathus
''Compsognathus'' (; Greek ''kompsos''/κομψός; "elegant", "refined" or "dainty", and ''gnathos''/γνάθος; "jaw") is a genus of small, bipedal, carnivorous theropod dinosaur. Members of its single species ''Compsognathus longipes'' could grow to around the size of a turkey. They lived about 150 million years ago, during the Tithonian age of the late Jurassic period, in what is now Europe. Paleontologists have found two well-preserved fossils, one in Germany in the 1850s and the second in France more than a century later. Today, ''C. longipes'' is the only recognized species, although the larger specimen discovered in France in the 1970s was once thought to belong to a separate species and named ''C. corallestris''. Many presentations still describe ''Compsognathus'' as "chicken-sized" dinosaurs because of the size of the German specimen, which is now believed to be a juvenile. ''Compsognathus longipes'' is one of the few dinosaur species whose diet is known with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Thomas Henry Huxley
Thomas Henry Huxley (4 May 1825 – 29 June 1895) was an English biologist and anthropologist specialising in comparative anatomy. He has become known as "Darwin's Bulldog" for his advocacy of Charles Darwin's theory of evolution. The stories regarding Huxley's famous 1860 Oxford evolution debate with Samuel Wilberforce were a key moment in the wider acceptance of evolution and in his own career, although some historians think that the surviving story of the debate is a later fabrication. Huxley had been planning to leave Oxford on the previous day, but, after an encounter with Robert Chambers, the author of '' Vestiges'', he changed his mind and decided to join the debate. Wilberforce was coached by Richard Owen, against whom Huxley also debated about whether humans were closely related to apes. Huxley was slow to accept some of Darwin's ideas, such as gradualism, and was undecided about natural selection, but despite this he was wholehearted in his public support of Darw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalosaurus
''Megalosaurus'' (meaning "great lizard", from Greek , ', meaning 'big', 'tall' or 'great' and , ', meaning 'lizard') is an extinct genus of large carnivorous theropod dinosaurs of the Middle Jurassic period (Bathonian stage, 166 million years ago) of Southern England. Although fossils from other areas have been assigned to the genus, the only certain remains of ''Megalosaurus'' come from Oxfordshire and date to the late Middle Jurassic. ''Megalosaurus'' was, in 1824, the first genus of non-avian dinosaur to be validly named. The type species is ''Megalosaurus bucklandii'', named in 1827. In 1842, ''Megalosaurus'' was one of three genera on which Richard Owen based his Dinosauria. On Owen's directions a model was made as one of the Crystal Palace Dinosaurs, which greatly increased the public interest for prehistoric reptiles. Over fifty other species would eventually be classified under the genus; at first, this was because so few types of dinosaur had been identified, but the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poekilopleuron
''Poekilopleuron'' (meaning "varied ribs") is a genus of tetanuran dinosaur, which lived during the middle Bathonian of the Jurassic, about 168 to 166 million years ago. The genus has been used under many different spelling variants, although only one, ''Poekilopleuron'', is valid. The type species is ''P. bucklandii'', named after William Buckland, and many junior synonyms of it have also been erected. Few material is currently known, as the holotype was destroyed in World War II, although many casts of the material still exist. Discovery and naming ''Poekilopleuron'' is a genus of theropod with a long and complex history. The holotype was discovered in July 1835 near La Maladrerie and the genus was named and first described by Jacques Amand Eudes-Deslongchamps in a report published in 1836, based on holotype material that is now destroyed. In 1837, Eudes-Deslongchamps published a more detailed account of this discovery in a monographEudes-Deslongchamps J.-A. (1837) Mémoire s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dryptosaurus
''Dryptosaurus'' ( ) is a genus of tyrannosauroid that lived approximately 67 million years ago (mya) during the latter part of the Cretaceous period, New Jersey. ''Dryptosaurus'' was a large, bipedal, ground-dwelling carnivore, that grow up to long and weigh up to . Although largely unknown now outside of academic circles, a famous painting of the genus by Charles R. Knight made ''Dryptosaurus'' one of the more widely known dinosaurs of its time, in spite of its poor fossil record. First described by Edward Drinker Cope in 1866 and later renamed by Othniel C. Marsh in 1877, ''Dryptosaurus'' is among the first theropod dinosaurs known to science. Discovery and species Prior to the discovery of ''Dryptosaurus'' in 1866, New World theropods were known only from some isolated theropod teeth discovered in Montana by Joseph Leidy in 1856. The discovery of this genus gave North American paleontologists the opportunity to observe an articulated, albeit incomplete, theropod skeleton. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euskelosaurus
''Euskelosaurus'' ("good leg lizard") is a sauropodomorph dinosaur from the Late Triassic of South Africa and Lesotho. Fossils have only been recovered from the lower Elliot Formation in South Africa and Lesotho, and in one locality in Zimbabwe. History of discovery In 1863, Alfred Brown recovered fossil material consisting of limb bones and vertebrae, in the lower Elliot Formation in the southeastern Free State. In 1866, Thomas Henry Huxley first described ''Euskelosaurus'' from Brown's fossil material, and named the holotype specimen ''Euskelosaurus brownii'' after Brown. Harry Seeley later described ''Euskelosaurus'' in 1894, as did Friedrich von Huene in 1902. Since then, other researchers, including Robert Broom, have mentioned ''Euskelosaurus'' in their papers, although later papers refer to the material under the name ''Plateosauravus''.Yates, A.M. (2003). A new species of the primitive dinosaur ''Thecodontosaurus'' (Saurischia: Sauropodomorpha) and its implications for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thecodontosaurus
''Thecodontosaurus'' ("socket-tooth lizard") is a genus of herbivorous basal sauropodomorph dinosaur that lived during the late Triassic period (Rhaetian age). Its remains are known mostly from Triassic "fissure fillings" in South England. ''Thecodontosaurus'' was a small bipedal animal, about 2 m (6.5 ft) long. It is one of the first dinosaurs to be discovered and is one of the oldest that existed. Many species have been named in the genus, but only the type species ''Thecodontosaurus antiquus'' is seen as valid today. Discovery and naming ''Thecodontosaurus antiquus'' In the autumn of 1834, surgeon Henry Riley (1797–1848) and the curator of the Bristol Institution, Samuel Stutchbury, began to excavate "saurian remains" at the quarry of Durdham Down, at Clifton, presently a part of Bristol, which is part of the Magnesian Conglomerate. In 1834 and 1835, they briefly reported on the finds. They provided their initial description in 1836, naming a new genus: ''Thecodo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scelidosauridae
''Scelidosaurus'' (; with the intended meaning of "limb lizard", from Greek / meaning 'rib of beef' and ''sauros''/ meaning 'lizard')Liddell & Scott (1980). Greek-English Lexicon, Abridged Edition. Oxford University Press, Oxford, UK. is a genus of herbivorous armoured ornithischian dinosaur from the Jurassic of the British Isles. ''Scelidosaurus'' lived during the Early Jurassic Period, during the Sinemurian to Pliensbachian stages around 191 million years ago. This genus and related genera at the time lived on the supercontinent Laurasia. Its fossils have been found in the Charmouth Mudstone Formation near Charmouth in Dorset, England, and these fossils are known for their excellent preservation. ''Scelidosaurus'' has been called the earliest complete dinosaur.Norman, David (2001). "''Scelidosaurus'', the earliest complete dinosaur" in ''The Armored Dinosaurs'', pp 3-24. Bloomington: Indiana University Press. . It is the most completely known dinosaur of the British Is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
