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Morrisonodon
''Morrisonodon brentbaatar'' is an extinct multituberculate mammal from the Upper Jurassic Morrison Formation of North America. ''M. brentbaatar'' was described by Robert T. Bakker in 1998, who originally placed it in the genus ''Ctenacodon''. The fossil remains consist of a jaw fragment containing two upper premolars and the sockets corresponding to two molars. The remains were found in the Upper Jurassic Morrison Formation in Wyoming. The species name honours the Wyoming paleontologist Brent Breithaupt, while "Baatar" is a Mongolian for "hero". Bakker assigned his specimens to ''Ctenacodon'' with hesitation, noting additional specimens may require a new classification. In a 2001 review of multituberculates, Zofia Kielan-Jaworowska and Jørn Hurum did not recognize Bakker's specimen as related to other ''Ctenacodon'' species or even belonging to the family Allodontidae, speculating the species might instead belong to the family Plagiaulacidae Plagiaulacidae is a family of ... [...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 clos ... [...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 din ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert T
The name Robert is an ancient Germanic given name, from Proto-Germanic "fame" and "bright" (''Hrōþiberhtaz''). Compare Old Dutch ''Robrecht'' and Old High German ''Hrodebert'' (a compound of '' Hruod'' ( non, Hróðr) "fame, glory, honour, praise, renown" and ''berht'' "bright, light, shining"). It is the second most frequently used given name of ancient Germanic origin. It is also in use as a surname. Another commonly used form of the name is Rupert. After becoming widely used in Continental Europe it entered England in its Old French form ''Robert'', where an Old English cognate form (''Hrēodbēorht'', ''Hrodberht'', ''Hrēodbēorð'', ''Hrœdbœrð'', ''Hrœdberð'', ''Hrōðberχtŕ'') had existed before the Norman Conquest. The feminine version is Roberta. The Italian, Portuguese, and Spanish form is Roberto. Robert is also a common name in many Germanic languages, including English, German, Dutch, Norwegian, Swedish, Scots, Danish, and Icelandic. It can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Upper 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 dinosaurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morrison Formation
The Morrison Formation is a distinctive sequence of Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone, and limestone and is light gray, greenish gray, or red. Most of the fossils occur in the green siltstone beds and lower sandstones, relics of the rivers and floodplains of the Jurassic period. It is centered in Wyoming and Colorado, with outcrops in Montana, North Dakota, South Dakota, Nebraska, Kansas, the panhandles of Oklahoma and Texas, New Mexico, Arizona, Utah, and Idaho. Equivalent rocks under different names are found in Canada. It covers an area of 1.5 million square kilometers (600,000 square miles), although only a tiny fraction is exposed and accessible to geologists and paleontologists. Over 75% is still buried under the prairie to the east, and much of its western paleogeographic extent was eroded during exhumation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Jurassic period. It is a member of the family Allodontidae within the order Multituberculata. ''Ctenacodon'', also known as ''Allodon'' (Marsh 1881), was named by Othniel Charles Marsh in 1879. At least three species are currently recognized. Present in stratigraphic zone 5. Remains possibly referrable to ''Ctenacodon'' have been recovered from stratigraphic zone 2.Foster, J. (2007). "Appendix." ''Jurassic West: The Dinosaurs of the Morrison Formation and Their World''. Indiana University Press. pp. 327-329. Species The species ''Ctenacodon laticeps'' was named by Marsh in 1881 and Simpson G.G. in 1927. It has also been known as ''Allodon laticeps'' (Marsh 1881). Remains were found in the Upper Jurassic strata of the Morrison Formation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premolar
The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered transitional teeth during chewing, or mastication. They have properties of both the canines, that lie anterior and molars that lie posterior, and so food can be transferred from the canines to the premolars and finally to the molars for grinding, instead of directly from the canines to the molars. Human anatomy The premolars in humans are the maxillary first premolar, maxillary second premolar, mandibular first premolar, and the mandibular second premolar. Premolar teeth by definition are permanent teeth distal to the canines, preceded by deciduous molars. Morphology There is always one large buccal cusp, especially so in the mandibular first premolar. The lower sec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wyoming
Wyoming () is a state in the Mountain West subregion of the Western United States. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the southwest, and Colorado to the south. With a population of 576,851 in the 2020 United States census, Wyoming is the least populous state despite being the 10th largest by area, with the second-lowest population density after Alaska. The state capital and most populous city is Cheyenne, which had an estimated population of 63,957 in 2018. Wyoming's western half is covered mostly by the ranges and rangelands of the Rocky Mountains, while the eastern half of the state is high-elevation prairie called the High Plains. It is drier and windier than the rest of the country, being split between semi-arid and continental climates with greater temperature extremes. Almost half of the land in Wyoming is owned by the federal government, generally protected for public uses. The stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mongolian Language
Mongolian is the official language of Mongolia and both the most widely spoken and best-known member of the Mongolic language family. The number of speakers across all its dialects may be 5.2 million, including the vast majority of the residents of Mongolia and many of the ethnic Mongol residents of the Inner Mongolia Autonomous Region of the People's Republic of China.Estimate from Svantesson ''et al.'' (2005): 141. In Mongolia, Khalkha Mongolian is predominant, and is currently written in both Cyrillic and traditional Mongolian script. In Inner Mongolia, the language is dialectally more diverse and is written in the traditional Mongolian script. However, Mongols in both countries often use the Latin script for convenience on the Internet. In the discussion of grammar to follow, the variety of Mongolian treated is the standard written Khalkha formalized in the writing conventions and in grammar as taught in schools, but much of what is to be said is also valid for ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zofia Kielan-Jaworowska
Zofia Kielan-Jaworowska (25 April 1925 – 13 March 2015) was a Polish paleobiologist. In the mid-1960s, she led a series of Polish-Mongolian paleontological expeditions to the Gobi Desert. She was the first woman to serve on the executive committee of the International Union of Geological Sciences. Early life and education Zofia Kielan-Jaworowska was born in Sokołów Podlaski, Poland, on April 25, 1925. In 1928, her father, Franciszek Kielan, was offered a job for the Association of Agriculture and Trade Cooperatives in Warsaw, to which her family moved for five years. Zofia and family returned to Warsaw in 1934 and lived in Żoliborz - a borough of Warsaw. She began her studies in Warsaw, following the destruction after the war when the Nazis had attempted to completely destroy the city, resulting in the Department of Geology joining the ruins. She attended lectures given instead by the Polish paleontologist, Roman Kozłowski, in his own home. This is her where her passion beg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jørn Hurum
Jørn Harald Hurum (born November 4, 1967) is a Norwegian paleontologist and popularizer of science. He is a vertebrate paleontologist and holds an Associate Professor position at the Natural History Museum of the University of Oslo. He has studied dinosaurs, primitive mammals and plesiosaurs. Media Hurum is known as a popularizer of science with a high media profile. He is the author of the book ''Menneskets utvikling'' ("The Evolution of Man") and the host of the segment ''Jørns hjørne'' ("Jørn's Corner") on the popular-science program "Newton" on Norwegian television. He also co-hosts the radio program ''Hurum og Ødegaard'' ("Hurum and Ødegaard") with astrophysicist Knut Jørgen Røed Ødegaard on Norwegian radio. In 2001, Hurum was awarded Oslo University's "Formidlingspris," an award for the popularization of science, which he shared with Hans Arne Nakrem and Geir Søli. He was awarded the prize again in 2009 for his work publicizing "Ida", the '' Darwinius' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
