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Ignavusaurus
''Ignavusaurus'' is a genus of basal sauropodomorph dinosaur that lived during the Early Jurassic in what is now Lesotho. Its fossils were found in the Upper Elliot Formation which is probably Hettangian in age (around 200 million years ago). It was described on the basis of a partial, well preserved articulated skeleton. The type species, ''I. rachelis'', was described in 2010 by Spanish palaeontologist F. Knoll. Discovery The holotype was discovered in southern Lesotho near Ha Ralekoala. The fossils were discovered in a mostly articulated state, although the skull was badly damaged, having broken into more than 120 fragments. An unpublished 2002 Ph.D. dissertation referred to the remains, but they were not formally described for several years, and the find remained unpublished. In 2010, the fossils were described by F. Knoll of the Museo Nacional de Ciencias Naturales-CSIC in Madrid as a new taxon, ''Ignavusaurus rachelis''. The fossils were brought to the National Museum of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massospondylus
''Massospondylus'' ( ; from Greek, (massōn, "longer") and (spondylos, "vertebra")) is a genus of sauropodomorph dinosaur from the Early Jurassic. (Hettangian to Pliensbachian ages, ca. 200–183 million years ago). It was described by Sir Richard Owen in 1854 from remains discovered in South Africa, and is thus one of the first dinosaurs to have been named. Fossils have since been found at other locations in South Africa, Lesotho, and Zimbabwe. Material from Arizona's Kayenta Formation, India, and Argentina has been assigned to the genus at various times, but the Arizonan and Argentinian material are now assigned to other genera. The type species is ''M. carinatus''; seven other species have been named during the past 150 years, but only ''M. kaalae'' is still considered valid. Early sauropodomorph systematics have undergone numerous revisions during the last several years, and many scientists disagree where exactly ''Massospondylus'' lies on the dinosaur evolutiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarahsaurus
''Sarahsaurus'' is a genus of basal sauropodomorph dinosaur which lived during the Early Jurassic period in what is now northeastern Arizona, United States. Discovery and naming All specimens of ''Sarahsaurus'' were collected from the Lower Jurassic Kayenta Formation near Gold Spring, Arizona. The genus is based on a nearly complete and articulated (with bones still connected to each other) skeleton with a fragmentary and disarticulated skull (holotype, specimen number TMM 43646-2). In addition, a partial skeleton (specimen number TMM 43646-3) as well as a nearly complete skull (specimen number MCZ 8893) was assigned to the genus. The latter specimen was originally referred to as ''Massospondylus'' sp. The complete skull is crushed and split horizontally, separating the skull roof from the palate; this split was caused by periodic swelling and shrinkage of the surrounding clay after burial. While the holotype individual was mature, the second skull indicates a less mature indi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massopoda
Massopoda is a clade of sauropodomorph dinosaurs which lived during the Late Triassic to Late Cretaceous epochs. It was named by paleontologist Adam M. Yates of the University of the Witwatersrand in 2007. Massopoda is a stem-based taxon, defined as all animals more closely related to ''Saltasaurus loricatus'' than to ''Plateosaurus engelhardti''. The name Massopoda, ; , is also contraction of Massospondylidae and Sauropoda, two disparate taxa in the clade. Classification Yates assigned the Massopoda to Plateosauria. Within the clade, he assigned the families Massospondylidae (which includes the relatively well-known dinosaur ''Massospondylus'') and Riojasauridae (which includes ''Riojasaurus'') as well as the Sauropoda. The following is a cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ance ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plateosauria
Plateosauria is a clade of sauropodomorph dinosaurs which lived during the Late Triassic to the Late Cretaceous. The name Plateosauria was first coined by Gustav Tornier in 1913. The name afterwards fell out of use until the 1980s. Classification Plateosauria is a node-based taxon. In 1998, Paul Sereno defined Plateosauria as the last common ancestor of ''Plateosaurus engelhardti'' and ''Massospondylus carinatus'', and its descendants. Peter Galton and Paul Upchurch in 2004 used a different definition: the last common ancestor of ''Plateosaurus engelhardti'' and '' Jingshanosaurus xinwaensis'', and its descendants. In their cladistic analysis the Plateosauria belonged to the Prosauropoda, and included the Plateosauridae subgroup. In Galton's and Upchurch's study also '' Coloradisaurus'', ''Euskelosaurus'', '' Jingshanosaurus'', ''Massospondylus'', ''Mussaurus'', ''Sellosaurus'', and ''Yunnanosaurus'' proved to be plateosaurians. However, recent cladistic analyses suggest that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper Elliot Formation
The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, southern Free State, and in the eastern KwaZulu-Natal provinces of South Africa. Outcrops and exposures are also found in several localities in Lesotho such as Qacha's Neck, Hill Top, Quthing, and near the capital, Maseru. The Elliot Formation is further divided into the lower (LEF) and upper (UEF) Elliot formations to differentiate significant sedimentological differences between these layers. The LEF is dominantly Late Triassic (Norian-Hettangian) in age while the UEF is mainly Early Jurassic (Sinemurian-Pliensbachian) and is tentatively regarded to preserve a continental record of the Triassic-Jurassic boundary in southern Africa. This geological formation is named after the town of Elliot in the Eastern Cape, and its stratotype locality ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the Roman Republic it became the dominant language in the Italian region and subsequently throughout the Roman Empire. Even after the fall of Western Rome, Latin remained the common language of international communication, science, scholarship and academia in Europe until well into the 18th century, when other regional vernaculars (including its own descendants, the Romance languages) supplanted it in common academic and political usage, and it eventually became a dead language in the modern linguistic definition. Latin is a highly inflected language, with three distinct genders (masculine, feminine, and neuter), six or seven noun cases (nominative, accusative, genitive, dative, ablative, and vocative), five declensions, four verb conjuga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistic
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saurischian
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] |
Herbivorous
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] |
Sauropodomorph
Sauropodomorpha ( ; from Greek, meaning "lizard-footed forms") is an extinct clade of long-necked, herbivorous, saurischian dinosaurs that includes the sauropods and their ancestral relatives. Sauropods generally grew to very large sizes, had long necks and tails, were quadrupedal, and became the largest animals to ever walk the Earth. The ''prosauropods,'' which preceded the sauropods, were smaller and were often able to walk on two legs. The sauropodomorphs were the dominant terrestrial herbivores throughout much of the Mesozoic Era, from their origins in the Late Triassic (approximately 230 Ma) until their decline and extinction at the end of the Cretaceous. Description Sauropodomorphs were adapted to browsing higher than any other contemporary herbivore, giving them access to high tree foliage. This feeding strategy is supported by many of their defining characteristics, such as: a light, tiny skull on the end of a long neck (with ten or more elongated cervical vertebrae) a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanorosaurus
''Melanorosaurus'' (meaning "Black Mountain Lizard", from the Greek ''melas/'', "black", ''oros/'', "mountain" + ''/'', "lizard") is a genus of basal sauropodomorph dinosaur that lived during the Late Triassic period. A herbivore from South Africa, it had a large body and sturdy limbs, suggesting it moved about on all fours. Its limb bones were massive and heavy like the limb bones of true sauropods. Description ''Melanorosaurus'' had a skull which measured approximately 250 mm. The snout was somewhat pointed, and the skull was somewhat triangular when seen from above or below. The premaxilla had four teeth on each side, a characteristic of primitive sauropodomorphs. The maxilla had 19 teeth on each side of the jaw. ''Melanorosaurus'' was around long, with a weight of . Discovery and species The type specimens, syntypes SAM 3449 and SAM 3450, were discovered, described and named in 1924 by Sidney H. Haughton. They were collected from the Triassic Lower ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Age Determination In Dinosaurs
Age determination in dinosaurs is mainly used to determine the approximate age of a dinosaur when the animal died. History Early attempts to estimate the longevity of dinosaurs used allometric scaling principles. Ages were determined by dividing individual mass estimates by rates of growth for similar, extant taxa. For very large individuals, growth rates were extrapolated to dinosaur proportions using regression analysis. The results of these investigations have been extremely variable as they depend on mass estimates and growth rates that are highly at odds with one another. For example, longevity estimates for the sauropod ''Hypselosaurus priscus'' range from a few decades to several hundred years. However, it has been shown that most dinosaur bones have growth lines that are visible in thin sectioned material viewed under a polarized light source. Growth lines Two types of growth lines exist: '' annuli'', and ''lines of arrested growth'' (LAGs).Francillion-Viellot H., ''et al.' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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