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Glirodon
''Glirodon'' is a genus of extinct mammal from the Upper Jurassic. It was a relatively early member of the also-extinct order of Multituberculata, suborder "Plagiaulacida". These mammals lived in North America during the Mesozoic, also known as the "age of the dinosaurs". The genus ''Glirodon'' has been described by Engelmann G.F. and Callison G. (1999) from a 'gliriform tooth'. The species ''Glirodon grandis'', also described by Engelmann and Callison, has been found in the Upper Jurassic formations of Dinosaur National Monument in Utah (United States). Other than being a large, early American Multituberculate, (see Multituberculata), the nature of this beast is somewhat unclear. It is an "allodontid (two families and the genus ''Glirodon'')", (Kielan-Jaworowska and Hurum, 2001). It had gliriform incisors; incisors with the "enamel reduced to a stripe on the front side." Apparently, this condition evolved several times among Multituberculates. It is based on a portion of sn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plagiaulacida
Plagiaulacida is a group of extinct multituberculate mammals. Multituberculates were among the most common mammals of the Mesozoic, "the age of the dinosaurs". Plagiaulacids are a paraphyletic grouping, containing all multituberculates that lie outside of the advanced group Cimolodonta. They ranged from the Middle Jurassic Period to the early Late Cretaceous of the northern hemisphere. During the Cenomanian, they were replaced by the more advanced cimolodontans. Kielan-Jaworowska and Hurum (2001) divides “Plagiaulacida” into three informal lineages, the paulchoffatiids, the plagiaulicids, and the allodontids. Allodontid line The Allodontid line may be a superfamily, Allodontoidea. Both allodontids and paulchoffatiids (below) were among the most basal of the plagiaulacids. The Allodontid line contains: The family Allodontidae is known from two genera from the Upper Jurassic Morrison Formation of North America. The family Zofiabaataridae contains a single genus, '' Zofia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multituberculates
Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, and reached a peak diversity during the Late Cretaceous and Paleocene. They eventually declined from the mid Paleocene onwards, disappearing from the known fossil record in the late Eocene. They are the most diverse order of Mesozoic mammals with more than 200 species known, ranging from mouse-sized to beaver-sized. These species occupied a diversity of ecological niches, ranging from burrow-dwelling to squirrel-like arborealism to jerboa-like hoppers. Multituberculates are usually placed as crown mammals outside either of the two main groups of living mammals—Theria, including placentals and marsupials, and MonotremataAgustí-Antón 2002, pp 3-4—but usually as closer to Theria than to monotremes. They are considered to be clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multituberculata
Multituberculata (commonly known as multituberculates, named for the multiple tubercles of their teeth) is an extinct order of rodent-like mammals with a fossil record spanning over 130 million years. They first appeared in the Middle Jurassic, and reached a peak diversity during the Late Cretaceous and Paleocene. They eventually declined from the mid Paleocene onwards, disappearing from the known fossil record in the late Eocene. They are the most diverse order of Mesozoic mammals with more than 200 species known, ranging from mouse-sized to beaver-sized. These species occupied a diversity of ecological niches, ranging from burrow-dwelling to squirrel-like arborealism to jerboa-like hoppers. Multituberculates are usually placed as crown mammals outside either of the two main groups of living mammals—Theria, including placentals and marsupials, and MonotremataAgustí-Antón 2002, pp 3-4—but usually as closer to Theria than to monotremes. They are considered to be clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Jurassic
The Late Jurassic is the third epoch of the Jurassic Period, and it spans the geologic time from 163.5 ± 1.0 to 145.0 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic strata.Owen 1987. In European lithostratigraphy, the name "Malm" indicates rocks of Late Jurassic age. In the past, ''Malm'' was also used to indicate the unit of geological time, but this usage is now discouraged to make a clear distinction between lithostratigraphic and geochronologic/chronostratigraphic units. Subdivisions The Late Jurassic is divided into three ages, which correspond with the three (faunal) stages of Upper Jurassic rock: Paleogeography During the Late Jurassic Epoch, Pangaea broke up into two supercontinents, Laurasia to the north, and Gondwana to the south. The result of this break-up was the spawning of the Atlantic Ocean. However, at this time, the Atlantic Ocean was relatively narrow. Life forms of the epoch This epoch is well known for many famous types of dinosau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its west by Nevada. Utah also touches a corner of New Mexico in the southeast. Of the fifty U.S. states, Utah is the 13th-largest by area; with a population over three million, it is the 30th-most-populous and 11th-least-densely populated. Urban development is mostly concentrated in two areas: the Wasatch Front in the north-central part of the state, which is home to roughly two-thirds of the population and includes the capital city, Salt Lake City; and Washington County in the southwest, with more than 180,000 residents. Most of the western half of Utah lies in the Great Basin. Utah has been inhabited for thousands of years by various indigenous groups such as the ancient Puebloans, Navajo and Ute. The Spanish were the first Europe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morrison Mammals
Morrison may refer to: People * Morrison (surname), people with the Scottish surname Morrison * Morrison Heady (1829–1915), American poet * Morrison Mann MacBride (1877–1938), Canadian merchant Places in the United States * Morrison, Colorado * Morrison, Illinois * Morrison, Iowa * Morrison, Missouri * Morrison, Oklahoma * Morrison, Tennessee * Morrison, Wisconsin, a town ** Morrison (community), Wisconsin, an unincorporated community * Morrison County, Minnesota * Morrison Township, Aitkin County, Minnesota Other uses * Clan Morrison, a Scottish clan * Morrison Formation, a distinctive sequence of Upper Jurassic sedimentary rock in the western United States * Morrison Hall, a residential hall at the University of Hong Kong * Webb Horton House, now known as Morrison Hall * Morrison Lake (other) * ''Morrison'', a 19th-century American merchant ship of the Morrison Incident * USS ''Morrison'' (DD-560), a ''Fletcher''-class destroyer sunk in the Pacific in 1945 * ''Ver ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allodontidae
Allodontidae (from ancient Greek "ἄλλος" "ὀδούς", "different tooth") is a family of extinct multituberculate mammal that lived in what is now North America during the Upper Jurassic period. They were relatively early mammals and are within the informal suborder of "Plagiaulacida". The family was named by Othniel Charles Marsh in 1889. Two genera are recognized: ''Ctenacodon ''Ctenacodon'' ("comb needle tooth" from Ancient Greek κτενός (ktenós), "comb" + Latin acus, "needle" + Ancient Greek ὀδών (odṓn), "tooth") is a genus of extinct mammal that lived in what is now North America during the Upper Jura ...'' and '' Psalodon''. References * Kielan-Jaworowska Z & Hurum JH (2001), "Phylogeny and Systematics of multituberculate mammals". ''Paleontology'' 44, p. 389-429. * Most of this information has been derived froMESOZOIC MAMMALS: Basal Multituberculata, an Internet directory. Multituberculates Late Jurassic first appearances Late Jura ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Formula
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology (that is, the relationship between the shape and form of the tooth in question and its inferred function) of the teeth of an animal. Animals whose teeth are all of the same type, such as most non-mammalian vertebrates, are said to have '' homodont'' dentition, whereas those whose teeth differ morphologically are said to have '' heterodont'' dentition. The dentition of animals with two successions of teeth (deciduous, permanent) is referred to as '' diphyodont'', while the dentition of animals with only one set of teeth throughout life is ''monophyodont''. The dentition of animals in which the teeth are continuously discarded and replaced throughout life is termed ''polyphyodont''. The dentition of animals in which the teeth are set in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incisor
Incisors (from Latin ''incidere'', "to cut") are the front teeth present in most mammals. They are located in the premaxilla above and on the mandible below. Humans have a total of eight (two on each side, top and bottom). Opossums have 18, whereas armadillos have none. Structure Adult humans normally have eight incisors, two of each type. The types of incisor are: * maxillary central incisor (upper jaw, closest to the center of the lips) * maxillary lateral incisor (upper jaw, beside the maxillary central incisor) * mandibular central incisor (lower jaw, closest to the center of the lips) * mandibular lateral incisor (lower jaw, beside the mandibular central incisor) Children with a full set of deciduous teeth (primary teeth) also have eight incisors, named the same way as in permanent teeth. Young children may have from zero to eight incisors depending on the stage of their tooth eruption and tooth development. Typically, the mandibular central incisors erupt first, followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of 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 produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, 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 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 specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosaur National Monument
Dinosaur National Monument is an American national monument located on the southeast flank of the Uinta Mountains on the border between Colorado and Utah at the confluence of the Green and Yampa rivers. Although most of the monument area is in Moffat County, Colorado, the Dinosaur Quarry is located in Utah, north of the town of Jensen, Utah. The nearest Colorado town is Dinosaur while the nearest city is Vernal, Utah. Originally preserved in 1915 to protect its famous Dinosaur Quarry, the monument was greatly expanded in 1938 to include its wealth of natural history. The park's wild landscapes, topography, geology, paleontology, and history make it a unique resource for both science and recreation. The park contains over 800 paleontological sites and has fossils of dinosaurs including ''Allosaurus'', ''Deinonychus'', '' Abydosaurus'', and various sauropods. The ''Abydosaurus'' consists of a nearly complete skull, the lower jaw, and first four neck vertebrae. The specimen was fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
