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Scymnognathus
''Gorgonops'' (from el, Γοργών 'Gorgon' and 'eye, face', literally 'Gorgon eye' or 'Gorgon face') is an extinct genus of gorgonopsian therapsids, of which it is the type genus, having lived during the Late Permian (Wuchiapingian), about 260–254 million years ago in what is now South Africa. Despite its popularity, ''Gorgonops'' is a medium-sized gorgonopsian (about long maximum), regularly confused by the general public with the more massive ''Inostrancevia'', known from Russia, due to their similar appearance and the various media that tend to refer them by the name of the group they belong rather than by their genus names, which does not help in differentiation. History of discovery The holotype of the type species, ''Gorgonops torvus'', was in 1876 one of the first therapsids described, by Richard Owen, who also coined the name "Dinosauria" on the basis of the first known dinosaur fossils. It was also used as the type for which Richard Lydekker described the fami ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gorgonops Torvus1DB
''Gorgonops'' (from el, Γοργών 'Gorgon' and 'eye, face', literally ' Gorgon eye' or 'Gorgon face') is an extinct genus of gorgonopsian therapsids, of which it is the type genus, having lived during the Late Permian ( Wuchiapingian), about 260–254 million years ago in what is now South Africa. Despite its popularity, ''Gorgonops'' is a medium-sized gorgonopsian (about long maximum), regularly confused by the general public with the more massive '' Inostrancevia'', known from Russia, due to their similar appearance and the various media that tend to refer them by the name of the group they belong rather than by their genus names, which does not help in differentiation. History of discovery The holotype of the type species, ''Gorgonops torvus'', was in 1876 one of the first therapsids described, by Richard Owen, who also coined the name "Dinosauria" on the basis of the first known dinosaur fossils. It was also used as the type for which Richard Lydekker des ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the abs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nimravidae
Nimravidae is an extinct family of carnivorans, sometimes known as false saber-toothed cats, whose fossils are found in North America and Eurasia. Not considered to belong to the true cats (family Felidae), the nimravids are generally considered closely related and classified as a distinct family in the suborder Feliformia. Fossils have been dated from the Middle Eocene through the Late Miocene epochs (Bartonian through Tortonian stages, 40.4–7.2 million years ago), spanning about . The barbourofelids, which were formerly classified as a subfamily of the Nimravidae, were reassigned to their own distinct family Barbourofelidae in 2004. However, some recent studies suggest the barbourofelids are a branch of the nimravids, suggesting that this debate might not be settled yet. Morphology and evolution Most nimravids had muscular, low-slung, cat-like bodies, with shorter legs and tails than are typical of cats. Unlike extant Feliformia, the nimravids had a different bone structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pareiasaurus
''Pareiasaurus'' is an extinct genus of pareiasauromorph reptile from the Permian period. It was a typical member of its family, the pareiasaurids, which take their name from this genus. Fossils have been found in the Beaufort Group. Description ''Pareiasaurus'' is a large quadruped, about long, with elephantine legs, walking in a typically reptilian posture. The skull is broad and the snout short. Its skull had several spine- and wart-like protrusions. ''Pareiasauruss leaf-shaped teeth, ideal for biting through tough plant fibers, indicate it was a herbivore. Even the palate The palate () is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but in most other tetrapods, the oral and nasal cavities are not truly s ... had teeth. Species ''P. nasicornis'' (Haughton and Boonstra, 1929) is from the ''Tropidostoma'' Zone, Karoo basin, South Africa. This early form is o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pareiasaur
Pareiasaurs (meaning "cheek lizards") are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with scutes which covered large areas of the body. They first appeared in southern Pangea during the Middle Permian, before becoming globally distributed during the Late Permian. Pareiasaurs were the largest reptiles of the Permian, reaching sizes equivalent to those of contemporary therapsids. Pareiasaurs became extinct at the end of the Permian during the Permian-Triassic extinction event. Description Pareiasaurs ranged in size from long, and may have weighed up to . They were stocky, with short tails, small heads, robust limbs, and broad feet. The cow-sized species '' Bunostegos'', which lived 260 million years ago, is the earliest known example of a tetrapod with a fully erect posture as its legs were positioned directly under its body. Pareiasaurs were protected by bony scutes called osteoderms that were set into the skin. Their heavy skulls ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cistecephalus Assemblage Zone
The ''Cistecephalus'' Assemblage Zone is a tetrapod assemblage zone or biozone found in the Adelaide Subgroup of the Beaufort Group, a majorly fossiliferous and geologically important geological group of the Karoo Supergroup in South Africa. This biozone has outcrops located in the Teekloof Formation north-west of Beaufort West in the Western Cape, in the upper Middleton Formation, Middleton and lower Balfour Formations respectively from Colesberg of the Northern Cape to east of Graaff-Reinet in the Eastern Cape. The ''Cistecephalus'' Assemblage Zone is one of eight biozones found in the Beaufort Group, and is considered to be Late Permian in age. The name of the biozone refers to ''Cistecephalus'', a small, burrowing dicynodont therapsid. It is characterized by the presence of this species, known especially from the upper sections of this biozone, and the first appearance of the dicynodont ''Aulacephalodon''. History The first fossils to be found in the Beaufort Group rocks th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropidostoma Assemblage Zone
The ''Tropidostoma'' Assemblage Zone is a tetrapod assemblage zone or biozone which correlates to the lower Teekloof Formation, Adelaide Subgroup of the Beaufort Group, a fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa. The thickest outcrops, reaching approximately , occur from east of Sutherland through to Beaufort West and Victoria West, to areas south of Graaff-Reinet. Its northernmost exposures occur west/north-west of Colesberg. The '' Tropidostoma'' Assemblage Zone is the fourth biozone of the Beaufort Group. The name of the biozone refers to '' Tropidostoma microtrema'', a herbivorous dicynodont therapsid. This biozone is characterized by the presence of this species in association with another dicynodont species, '' Endothiodon uniseries''. History The first fossils to be found in the Beaufort Group rocks that encompass the current eight biozones were discovered by Andrew Geddes Bain in 1856. How ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beaufort Group
The Beaufort Group is the third of the main subdivisions of the Karoo Supergroup in South Africa. It is composed of a lower Adelaide Subgroup and an upper Tarkastad Subgroup. It follows conformably after the Ecca Group and unconformably underlies the Stormberg Group. Based on stratigraphic position, lithostratigraphic and biostratigraphic correlations, palynological analyses, and other means of geological dating, the Beaufort Group rocks are considered to range between Middle Permian ( Wordian) to Early Triassic (Anisian) in age. Background During the period when sedimentation of the Beaufort Group rocks took place, the Ecca sea had retreated to the northeastern Karoo Basin. All sediment deposition at this time took place in a terrestrial, although in a predominantly fluvial or alluvial environment that was seasonally arid. This environment covered a vast area and deposition was influenced by a retroarc foreland basin. This foreland system was caused by crustal uplift ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karoo
The Karoo ( ; from the Afrikaans borrowing of the South Khoekhoe !Orakobab or Khoemana word ''ǃ’Aukarob'' "Hardveld") is a semi- desert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its extent is also not precisely defined. The Karoo is partly defined by its topography, geology and climate, and above all, its low rainfall, arid air, cloudless skies, and extremes of heat and cold.Potgieter, D.J. & du Plessis, T.C. (1972) ''Standard Encyclopaedia of Southern Africa''. Vol. 6. pp. 306–307. Nasou, Cape Town.''Reader’s Digest Illustrated Guide to Southern Africa''. (5th Ed. 1993). pp. 78–89. Reader’s Digest Association of South Africa Pty. Ltd., Cape Town. The Karoo also hosted a well-preserved ecosystem hundreds of million years ago which is now represented by many fossils. The ǃ’Aukarob formed an almost impenetrable barrier to the interior from Cape Town, and the early adventurers, explorers, hunters, and traveler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denise Sigogneau-Russell
Denise Sigogneau-Russell (born ''c.'' 1941/42) is a French palaeontologist who specialises in mammals from the Mesozoic, particularly from France and the UK. She is currently based at the Muséum National d'Histoire Naturelle. Background Denise Sigogneau-Russell completed her PhD in 1969 on therapsids - the forerunners of mammals - from South Africa, where she spent two years. In 1976 a Belgian amateur fossil hunter brought her a mammal tooth from a quarry in eastern France, and this inspired her to change direction and begin research on mammals from the Mesozoic.Kielan-Jaworowska, Z. 2013. ''In Pursuit of Early Mammals''. Indiana University Press. She subsequently studied them in France, Portugal, Madagascar, Morocco, and England. Zofia Kielan-Jaworowska said that due to Sigogneau-Russell's "scholarship and diligence, she has contributed enormously to the knowledge of early mammal evolution.". She was married to Donald E. Russell, also a palaeontologist specialising in mammals, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can reproduction, produce Fertility, fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
