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Abelisaurinae
Carnotaurini is a tribe of the theropod dinosaur family Abelisauridae from the Late Cretaceous period of Patagonia. It includes the dinosaurs ''Carnotaurus sastrei''; the type species, ''Aucasaurus garridoi'', and ''Abelisaurus comahuensis''. This group was first proposed by paleontologists Rodolfo Coria, Luis Chiappe, and Lowell Dingus in 2002, being defined as a clade containing "''Carnotaurus sastrei'', ''Aucasaurus garridoi'', their most recent common ancestor, and all of its decendants." Description Anatomical description and geological distribution Carnotaurins were relatively lightly built but large theropods, ranging in size from 6.1-7.8 m (20-25.6 ft) and 1400–2000 kg (1.6-2.3 tons) in weight. Their geographical distribution lied in South America, as all three species have been found in various formations in Argentina, being the Anacleto Formation of the Rio Colorado Subgroup in the Neuquén Basin and possibly the Sir Fernandez field of the Allen Formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous–Paleogene Boundary
The Cretaceous–Paleogene (K–Pg) boundary, formerly known as the Cretaceous–Tertiary (K–T) boundary, is a geological signature, usually a thin band of rock containing much more iridium than other bands. The K–Pg boundary marks the end of the Cretaceous Period, the last period of the Mesozoic Era, and marks the beginning of the Paleogene Period, the first period of the Cenozoic Era. Its age is usually estimated at around 66 million years, with radiometric dating yielding a more precise age of 66.043 ± 0.011 Ma. The K–Pg boundary is associated with the Cretaceous–Paleogene extinction event, a mass extinction which destroyed a majority of the world's Mesozoic species, including all dinosaurs except for birds. Strong evidence exists that the extinction coincided with a large meteorite impact at the Chicxulub crater and the generally accepted scientific theory is that this impact triggered the extinction event. The word "Cretaceous" is derived from the Latin "creta" (ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rio Colorado Subgroup
Rio or Río is the Portuguese, Spanish, Italian, and Maltese word for "river". When spoken on its own, the word often means Rio de Janeiro, a major city in Brazil. Rio or Río may also refer to: Geography Brazil * Rio de Janeiro * Rio do Sul, a town in the state of Santa Catarina, Brazil Mexico * Río Bec, a Mayan archaeological site in Mexico * Río Bravo, Tamaulipas, a city in Mexico United States * Rio, a location in Deerpark, New York, US * Rio, Florida, a census-designated place in Martin County, US * Rio, Georgia, an unincorporated community in Spalding County, US * Rio, Illinois, a village in Knox County, US * Rio, Virginia, a community in Albemarle County, US * Rio, West Virginia, a village in Hampshire County, US * Rio, Wisconsin, a village in Columbia County, US * El Río, Las Piedras, Puerto Rico, a barrio * Río Arriba, Añasco, Puerto Rico, a barrio * Río Arriba, Arecibo, Puerto Rico, a barrio * Río Arriba, Fajardo, Puerto Rico, a barrio * Río Arriba, Vega Baja, P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetanurae
Tetanurae (/ˌtɛtəˈnjuːriː/ or "stiff tails") is a clade that includes most theropod dinosaurs, including megalosauroids, allosauroids, tyrannosauroids, ornithomimosaurs, compsognathids and maniraptorans (including birds). Tetanurans are defined as all theropods more closely related to modern birds than to ''Ceratosaurus'' and contain the majority of predatory dinosaur diversity. Tetanurae likely diverged from its sister group, Ceratosauria, during the late Triassic. Tetanurae first appeared in the fossil record by the Early Jurassic about 190 mya and by the Middle Jurassic had become globally distributed. The group was named by Jacques Gauthier in 1986 and originally had two main subgroups: Carnosauria and Coelurosauria, the clade containing birds and related dinosaurs such as compsognathids, tyrannosaurids, ornithomimosaurs, and maniraptorans. The original Carnosauria was a polyphyletic group including any large carnivorous theropod. Many of Gauthier's carnosaurs, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avetheropoda
Avetheropoda, or "bird theropods", is a clade that includes carnosaurians and coelurosaurs to the exclusion of other dinosaurs. Definition Avetheropoda was named by Gregory S. Paul in 1988, and was first defined as a clade by Currie and Padian in 1997, to include ''Allosaurus'', modern birds, and other animals descended from their most recent ancestor. In 1999, Paul Sereno named another group, Neotetanurae, for the clade containing Allosauroidea and Coelurosauria, and excluding other tetanurans such as megalosauroids, but this definition was published slightly later. A monophyletic Avetheropoda is recovered in many papers, however recent findings suggest a monophyletic Carnosauria model with allosauroids and megalosauroids being each other’s closest relatives instead of Allosaurs and Coelurosaurs. Classification The cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Most Recent Common Ancestor
In biology and genetic genealogy, the most recent common ancestor (MRCA), also known as the last common ancestor (LCA) or concestor, of a set of organisms is the most recent individual from which all the organisms of the set are descended. The term is also used in reference to the ancestry of groups of genes (haplotypes) rather than organisms. The MRCA of a set of individuals can sometimes be determined by referring to an established pedigree. However, in general, it is impossible to identify the exact MRCA of a large set of individuals, but an estimate of the time at which the MRCA lived can often be given. Such ''time to most recent common ancestor'' (''TMRCA'') estimates can be given based on DNA test results and established mutation rates as practiced in genetic genealogy, or by reference to a non-genetic, mathematical model or computer simulation. In organisms using sexual reproduction, the ''matrilineal MRCA'' and ''patrilineal MRCA'' are the MRCAs of a given population ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CBC News
CBC News is a division of the Canadian Broadcasting Corporation responsible for the news gathering and production of news programs on the corporation's English-language operations, namely CBC Television, CBC Radio, CBC News Network, and CBC.ca. Founded in 1941, CBC News is the largest news broadcaster in Canada and has local, regional, and national broadcasts and stations. It frequently collaborates with its organizationally separate French-language counterpart, Radio-Canada Info. History The first CBC newscast was a bilingual radio report on November 2, 1936. The CBC News Service was inaugurated during World War II on January 1, 1941, when Dan McArthur, chief news editor, had Wells Ritchie prepare for the announcer Charles Jennings a national report at 8:00 pm. Readers who followed Jennings were Lorne Greene, Frank Herbert and Earl Cameron. ''CBC News Roundup'' (French counterpart: ''La revue de l'actualité'') started on August 16, 1943, at 7:45 pm, being replaced by ''T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caudofemoralis
The caudofemoralis (from the Latin ''cauda'', tail and ''femur'', thighbone) is a muscle found in the pelvic limb of mostly all animals possessing a tail. It is thus found in nearly all tetrapods. Location The caudofemoralis spans plesiomorphically between femur (thigh) and tail; in mammals it is reduced and found directly posterior/ caudal to the gluteus maximus and directly anterior/ cranial to the biceps femoris. Origin and insertion The caudofemoralis originates from the transverse processes of the second, third and fourth caudal vertebrae. The caudodistal portion of the muscle in mammals lies deep to the proximocranial portion of the Biceps femoris; near the middle of the thigh, the caudofemoralis gives rise to a long, thin, and narrow tendon that passes distally to the knee joint and inserts into the fascia lata that is anchored to the lateral border of the patella. Among archosaurians the caudofemoralis is divided in a ''pars pelvica/brevis'' (characterized by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bending Moment
In solid mechanics, a bending moment is the reaction induced in a structural element when an external force or moment is applied to the element, causing the element to bend. The most common or simplest structural element subjected to bending moments is the beam. The diagram shows a beam which is simply supported (free to rotate and therefore lacking bending moments) at both ends; the ends can only react to the shear loads. Other beams can have both ends fixed (known as encastre beam); therefore each end support has both bending moments and shear reaction loads. Beams can also have one end fixed and one end simply supported. The simplest type of beam is the cantilever, which is fixed at one end and is free at the other end (neither simple or fixed). In reality, beam supports are usually neither absolutely fixed nor absolutely rotating freely. The internal reaction loads in a cross-section of the structural element can be resolved into a resultant force and a resultant couple. F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phil Currie
Philip John Currie (born March 13, 1949) is a Canadian palaeontologist and museum curator who helped found the Royal Tyrrell Museum of Palaeontology in Drumheller, Alberta and is now a professor at the University of Alberta in Edmonton. In the 1980s, he became the director of the Canada-China Dinosaur Project, the first cooperative palaeontological partnering between China and the West since the Central Asiatic Expeditions in the 1920s, and helped describe some of the first feathered dinosaurs. He is one of the primary editors of the influential ''Encyclopedia of Dinosaurs'', and his areas of expertise include theropods (especially Tyrannosauridae), the origin of birds, and dinosaurian migration patterns and herding behavior. He was one of the models for palaeontologist Alan Grant in the film ''Jurassic Park''. Biography Currie received his Bachelor of Science degree from the University of Toronto in 1972, a Master of Science degree from McGill University in 1975, and a Doc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allosaurus
''Allosaurus'' () is a genus of large carnosaurian theropod dinosaur that lived 155 to 145 million years ago during the Late Jurassic epoch (Kimmeridgian to late Tithonian). The name "''Allosaurus''" means "different lizard" alluding to its unique (at the time of its discovery) concave vertebrae. It is derived from the Greek (') ("different, other") and (') ("lizard / generic reptile"). The first fossil remains that could definitively be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles. ''Allosaurus'' was a large bipedal predator. Its skull was light, robust and equipped with dozens of sharp, serrated teeth. It averaged in length for ''A. fragilis'', with the largest specimens estimated as being long. Relative to the large and powerful hindlimbs, its three-fingered forelimbs were small, and the body was balanced b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of the Mesozoic, Mesozoic Era and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province. The beginning of the Toarcian Stage started around 183 million years ago and is marked by an extinction event associated with widespread Anoxic event, oceanic anoxia, ocean acidification, and elevated temperatures likely caused by the eruption of the Karoo-Ferrar, Karoo-Ferrar large igneous provinces. The end of the Jurassic, however, has no clear boundary with the Cretaceous and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Occiput
The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cerebrum. At the base of skull in the occipital bone, there is a large oval opening called the foramen magnum, which allows the passage of the spinal cord. Like the other cranial bones, it is classed as a flat bone. Due to its many attachments and features, the occipital bone is described in terms of separate parts. From its front to the back is the basilar part, also called the basioccipital, at the sides of the foramen magnum are the lateral parts, also called the exoccipitals, and the back is named as the squamous part. The basilar part is a thick, somewhat quadrilateral piece in front of the foramen magnum and directed towards the pharynx. The squamous part is the curved, expanded plate behind the foramen magnum and is the largest part o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
