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Simplicidentata
Simplicidentata is a group of mammals that includes the rodents (order Rodentia) and their closest extinct relatives. The term has historically been used as an alternative to Rodentia, contrasting the rodents (which have one pair of upper incisors) with their close relatives the lagomorphs (which have two). However, Simplicidentata is now defined as including all members of Glires (the clade formed by lagomorphs and rodents) that share a more recent common ancestor with living rodents than with living lagomorphs. Thus, Simplicidentata is a total group that is more inclusive than Rodentia, a crown group that includes all living rodents, their last common ancestor, and all its descendants. Under this definition, the loss of the second pair of upper incisors is a synapomorphic (shared derived) feature of Simplicidentata. The loss of the second upper premolar (P2) has also been considered as synapomorphic for Simplicidentata, but the primitive simplicidentate '' Sinomylus'' does have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurymylidae
Eurymylidae is a family (biology), family of extinct Simplicidentata, simplicidentates. Most authorities consider them to be Basal (phylogenetics), basal to all modern rodents and may have been the ancestral stock whence the most recent common ancestor of all modern rodents (crown rodents) arose. However, the more completely known eurymylids, including ''Eurymylus'', ''Heomys'', ''Matutinia'', and ''Rhombomylus'', appear to represent a monophyletic side branch not directly ancestral to rodents (Meng et al., 2003). Huang et al. (2004) have argued that ''Hanomys'', ''Matutinia'', and ''Rhombomylus'' form a clade characterized by distinctive features of the skull and dentition that should be recognized as a separate family, Rhombomylidae. Eurymylids are only known from Asia. Classification Modified from McKenna and Bell (1997) following generic taxonomy of Ting et al. (2002) and Huang et al. (2004) *Mirorder Simplicidentata – simplicidentates **Family †Eurymylidae ***†''Heo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glires
Glires (, Latin ''glīrēs'' 'dormice') is a clade (sometimes ranked as a grandorder) consisting of rodents and lagomorphs ( rabbits, hares, and pikas). The hypothesis that these form a monophyletic group has been long debated based on morphological evidence. Two morphological studies, published in 2001 and 2003, strongly support the monophyly of Glires. In particular, the 2003 study reported the discovery of fossil material of basal members of Glires, particularly the genera '' Mimotona'', '' Gomphos'', '' Heomys'', '' Matutinia'', '' Rhombomylus'', and '' Sinomylus''. Their description, in 2005, helped to bridge the gap between more typical rodents and lagomorphs. Data published in 2001, based on nuclear DNA, supported Glires as a sister of Euarchonta to form Euarchontoglires, but some genetic data from both nuclear and mitochondrial DNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Paleocene
The Danian is the oldest age (geology), age or lowest stage (stratigraphy), stage of the Paleocene Epoch or series (stratigraphy), Series, of the Paleogene Period or system (stratigraphy), System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretaceous–Paleogene extinction event . The age ended , being followed by the Selandian. Stratigraphic definitions The Danian was introduced in scientific literature by Germany, German-Switzerland, Swiss geologist Pierre Jean Édouard Desor in 1847 following a study of fossils found in France and Denmark.Danien Den Store Danske Encyklopædi He identified this stage in deposits from Faxe and Møns Klint and named it after the Latin name for Denmark. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duplicidentata
The lagomorphs () are the members of the taxonomic order Lagomorpha, of which there are two living families: the Leporidae (rabbits and hares) and the Ochotonidae (pikas). There are 110 recent species of lagomorph, of which 109 species in twelve genera are extant, including ten genera of rabbits (42 species); one genus of hare (33 species) and one genus of pika (34 species). The name of the order is derived from the Ancient Greek (, "hare") + (, "form"). Taxonomy and evolutionary history Other names used for this order, now considered synonymous, include: ''Duplicidentata'' (Illiger, 1811); ''Leporida'' (Averianov, 1999); ''Neolagomorpha'' (Averianov, 1999); ''Ochotonida'' (Averianov, 1999); and ''Palarodentia'' (Haeckel, 1895; Lilian, 2016). The evolutionary history of the lagomorphs is still not well understood. In the late 20th century, it was generally agreed that '' Eurymylus'', which lived in eastern Asia and dates back to the late Paleocene or early Eocene, was an anc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Osteology
Osteology () is the scientific study of bones, practiced by osteologists . A subdiscipline of anatomy, anthropology, archaeology and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, function, disease, pathology, the process of ossification from cartilaginous molds, and the resistance and hardness of bones (biophysics). Osteologists frequently work in the public and private sector as consultants for museums, scientists for research laboratories, scientists for medical investigations and/or for companies producing osteological reproductions in an academic context. The role of an osteologist entails understanding the macroscopic and microscopic anatomies of bones for both humans and non-humans (courses in non-human osteology is known as zooarchaeology). Osteology and osteologists should not be confused with the pseudoscientific practice of osteopathy and its practitioners, osteopaths. Methods A typica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia University Press
Columbia University Press is a university press based in New York City New York, often called New York City (NYC), is the most populous city in the United States, located at the southern tip of New York State on one of the world's largest natural harbors. The city comprises five boroughs, each coextensive w ..., and affiliated with Columbia University. Founded in 1893, it is currently directed by Jennifer Crewe (2014–present) and publishes titles in the humanities and sciences, including the fields of literary and cultural studies, history, social work, sociology, religion, film, and international studies. History Columbia University Press was founded in May 1893. In 1933, the first four volumes of the ''History of the State of New York'' were published. In the early 1940s, the Press' revenues rose, partially thanks to the ''Encyclopedia'' and the government's purchase of 12,500 copies for use by the military. Columbia University Press is notable for publishing r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''Ēṓs'', 'Eos, Dawn') and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.See: *Letter from William Whewell to Charles Lyell dated 31 January 1831 in: * From p. 55: "The period next antecedent we shall call Eocene, from ήως, aurora, and χαινος, recens, because the extremely small proportion of living species contained in these strata, indicates what may be considered the first commencement, or ''dawn'', of the existing state of the animate creation." The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact (Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macroscelidea
Elephant shrews, also called jumping shrews or sengis, are small insectivorous mammals native to Africa, belonging to the family Macroscelididae, in the order Macroscelidea. Their traditional common English name "elephant shrew" comes from a perceived resemblance between their long noses and the trunk of an elephant, and their superficial similarity with shrews (family Soricidae) in the order Eulipotyphla. However, phylogenetic analysis has revealed that elephant shrews are not properly classified with true shrews, but are in fact more closely related to elephants than to shrews. In 1997, the biologist Jonathan Kingdon proposed that they instead be called "sengis" (singular ''sengi''), a term derived from the Bantu languages of Africa, and in 1998, they were classified into the new clade Afrotheria. They are widely distributed across the southern part of Africa, and although common nowhere, can be found in almost any type of habitat, from the Namib Desert to boulder-strewn out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anagalida
Anagaloidea is a former order of extinct placental mammals that first appeared during the Paleocene epoch. Taxonomy According to the traditional (morphological) view, Anagaloidea is part of the superorder Anagalida, along with the elephant shrews, rodents and lagomorphs. However, the Anagalida are considered to be polyphyletic. Genetic studies have shown that the elephant shrews are actually part of a different macro-group of mammals called the Afrotheria, while the position of several extinct families of Anagalida is uncertain. The Zalambdalestidae are almost certainly unrelated to any of these groups; they probably represent more basal Eutherians and might not even be true Eutherians at all. The Anagalidae and the Pseudictopidae probably represent a genuine clade. This clade is known as the Anagaloidea, which seems to be related to the rodents and lagomorphs after all. Together they form the clade Glires, often grouped with the Euarchonta to form the superorder Euarchontogl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grandorder
Order () is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. For some groups of organisms, their orders may follow consistent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
