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Eudromaeosaurs
Eudromaeosauria ( ; "true dromaeosaurs") is a subgroup of terrestrial dromaeosaurid theropod dinosaurs. They were small to large-sized predators that flourished during the Cretaceous Period. Eudromaeosaur fossils are known almost exclusively from the northern hemisphere. They first appeared in the early Cretaceous Period and survived until the end of the Cretaceous (Maastrichtian stage, Ma). The earliest known definitive eudromaeosaur is the probable dromaeosaurine '' Yurgovuchia'', from the Cedar Mountain Formation, dated to 139 million years ago. However, the earlier (143-million-year-old) fossils such as those of '' Nuthetes'' and several indeterminate teeth dating to the Kimmeridgian stage may represent eudromaeosaurs. While other dromaeosaurids filled a variety of specialized ecological niches, mainly those of small predators or specialized piscivores, eudromaeosaurs functioned as hypercarnivores and are suggested to have been predators of medium- to large-sized prey. As ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eudromaeosauria
Eudromaeosauria (International Phonetic Alphabet, ; "true dromaeosaurs") is a subgroup of terrestrial Dromaeosauridae, dromaeosaurid theropod dinosaurs. They were small to large-sized predators that flourished during the Cretaceous Period (geology), Period. Eudromaeosaur fossils are known almost exclusively from the northern hemisphere. They first appeared in the early Cretaceous Period and survived until the end of the Cretaceous (Maastrichtian stage, Ma). The earliest known definitive eudromaeosaur is the probable dromaeosaurine ''Yurgovuchia'', from the Cedar Mountain Formation, dated to 139 million years ago. However, the earlier (143-million-year-old) fossils such as those of ''Nuthetes'' and several indeterminate teeth dating to the Kimmeridgian stage may represent eudromaeosaurs. While other dromaeosaurids filled a variety of specialized ecological niches, mainly those of small predators or specialized piscivores, eudromaeosaurs functioned as hypercarnivores and are sug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 Megaannum#SI prefix multipliers, Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian–Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining Anoxic event#Cretaceous, early Aptian Oceanic Anoxic Event 1a (OAE1a) was dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java Plateau, Ontong Java-Manihiki Plateau, Manihiki-Hikurangi Plateau, Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Onto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cedar Mountain Formation
The Cedar Mountain Formation is the name given to a distinctive sedimentary geologic formation in eastern Utah, spanning most of the early and mid-Cretaceous. The formation was named for Cedar Mountain (Utah), Cedar Mountain in northern Emery County, Utah, where William Lee Stokes first studied the exposures in 1944. Geology The formation occurs between the underlying Morrison Formation and overlying Naturita Formation (sometimes formerly called the Dakota Formation). It is composed of non-marine sediments, that is, sediments deposited in rivers, lakes and on flood plains. Based on various fossils and radiometric dating, radiometric dates, the Cedar Mountain Formation was deposited during the last half of the Early Cretaceous Epoch, about 127 - 98 million years ago (mya). It has lithography similar to the Burro Canyon Formation in the region. Dinosaur fossils occur throughout the formation, but their study has only occurred since the early 1990s. The dinosaurs in the lower par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unenlagia
''Unenlagia'' (meaning "half-bird" in Latinized Mapudungun) is a genus of dromaeosaurid theropod dinosaur that lived in South America during the Late Cretaceous period. The genus ''Unenlagia'' has been assigned two species: ''U. comahuensis'', the type species described by Novas and Puerta in 1997, and ''U. paynemili'', described by Calvo ''et al.'' in 2004. Discovery and naming In 1996 in the Neuquén province of Argentina a skeleton of a theropod was discovered in the Sierra del Portezuelo and reported the same year. In 1997 Fernando Emilio Novas and Pablo Puerta named and described ''Unenlagia comahuensis''. The generic name is derived from Mapuche ''uñùm'', 'bird', and ''llag'', 'half', in reference to the fact that the describers considered the species to be a link between birds and more basal theropods. The specific name refers to the Comahue, the region the find was made. The holotype specimen, MCF PVPH 78, was uncovered in layers of the Portezuelo Formation dating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Passer
''Passer'' is a genus of Old World sparrow, sparrows, also known as the true sparrows. The genus contains 28 species and includes the house sparrow and the Eurasian tree sparrow, two of the most common birds in the world. They are small birds with thick bills for eating seeds, and are mostly coloured grey or brown. Native to the Old World, some species have been introduced throughout the world. Taxonomy The genus ''Passer'' was introduced by the French zoologist Mathurin Jacques Brisson in 1760. The type species was subsequently designated as the house sparrow (''Passer domesticus''). The name ''Passer'' is the Latin word for "sparrow." Species The genus contains 28 species: Besides these living species, there are questionable fossils from as long ago as the Early Miocene, and ''Passer predomesticus'', from the Middle Pleistocene. Description These sparrows are plump little brown or greyish birds, often with black, yellow or white markings. Typically long, they range ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microraptor
''Microraptor'' (Greek language, Greek, μικρός, ''mīkros'': "small"; Latin language, Latin, ''raptor'': "one who seizes") is a genus of small, four-winged dromaeosaurid dinosaurs. Numerous well-preserved fossil specimens have been recovered from Liaoning, China. They date from the early Cretaceous Jiufotang Formation (Aptian stage), 125 to 120 million years ago. Three species have been named (''M. zhaoianus'', ''M. gui'', and ''M. hanqingi''), though further study has suggested that all of them represent variation in a single species, which is properly called ''M. zhaoianus''. ''Cryptovolans'', initially described as another four-winged dinosaur, is usually considered to be a synonym of ''Microraptor''. Like ''Archaeopteryx'', well-preserved fossils of ''Microraptor'' provide important evidence about the evolutionary relationship between birds and earlier dinosaurs. ''Microraptor'' had long pennaceous feathers that formed aerodynamic surfaces on the arms and tail but a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dromaeosaurus
''Dromaeosaurus'' (; ) is a genus of Dromaeosauridae, dromaeosaurid theropod dinosaur that lived during the Late Cretaceous period (middle late Campanian and Maastrichtian), sometime between 80 and 69 million years ago, in Alberta, Canada and the western United States. The type (biology), type species is ''Dromaeosaurus albertensis'', which was described by William Diller Matthew and Barnum Brown in 1922 in paleontology, 1922. Its fossils were unearthed in the Hell Creek Formation, Horseshoe Canyon Formation and Dinosaur Park Formation. Teeth attributed to this genus have been found in the Prince Creek Formation. ''Dromaeosaurus'' is the type genus of both Dromaeosauridae and Dromaeosaurinae, which include many genera with similar characteristics to ''Dromaeosaurus'' such as possibly its closest relative ''Dakotaraptor''. ''Dromaeosaurus'' was heavily built, more so than other dromaeosaurs that are similar in size, like ''Velociraptor''. Discovery and naming Despite receiving wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monophyletic
In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent common ancestor (or more precisely an ancestral population), i.e. excludes non-descendants of that common ancestor # the grouping contains all the descendants of that common ancestor, without exception Monophyly is contrasted with paraphyly and polyphyly as shown in the second diagram. A ''paraphyletic'' grouping meets 1. but not 2., thus consisting of the descendants of a common ancestor, excepting one or more monophyletic subgroups. A '' polyphyletic'' grouping meets neither criterion, and instead serves to characterize convergent relationships of biological features rather than genetic relationships – for example, night-active primates, fruit trees, or aquatic insects. As such, these characteristic features of a polyphyletic grouping ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tyrannosauridae
Tyrannosauridae (or tyrannosaurids, meaning "tyrant lizards") is a family of coelurosaurian theropod dinosaurs that comprises two subfamilies containing up to fifteen genera, including the eponymous ''Tyrannosaurus''. The exact number of genera is controversial, with some experts recognizing as few as three. All of these animals lived near the end of the Cretaceous Period and their fossils have been found only in North America and Asia. Although descended from smaller ancestors, tyrannosaurids were almost always the largest predators in their respective ecosystems, putting them at the apex of the food chain. The largest species was ''Tyrannosaurus rex'', the most massive known terrestrial predator, which measured over in length and according to most modern estimates up to in weight. Tyrannosaurids were bipedal carnivores with massive skulls filled with large teeth. Despite their large size, their legs were long and proportioned for fast movement. In contrast, their arms were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barnum Brown
Barnum Brown (February 12, 1873 – February 5, 1963), commonly referred to as Mr. Bones, was an American paleontologist. He discovered the first documented remains of ''Tyrannosaurus'' during a career that made him one of the most famous fossil hunters working from the late Victorian era into the early 20th century. Family and early life Barnum Brown was born in Carbondale, Kansas on February 12, 1873 to William and Clara Silver Brown. Brown's parents moved to Kansas in 1859, traveling by covered wagon with their daughter, Melissa. Their second daughter, Alice Elizabeth, was born in 1860 in Osage County, Kansas, where the family would build a one-room cabin on top of a coal seam. William made a living in Kansas first by raising corn, hogs, and cattle, but the political turmoil of Bleeding Kansas in the late 1850s and 1860s led to arson and theft of crops and livestock; he supported the family by digging and selling coal, as well as hauling supplies for the government with a fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Diller Matthew
William Diller Matthew FRS (February 19, 1871 – September 24, 1930) was a vertebrate paleontologist who worked primarily on mammal fossils, although he also published a few early papers on mineralogy, petrological geology, one on botany, one on trilobites, and he described '' Tetraceratops insignis'', which was much later suggested to be the oldest known (Early Permian) therapsid. Matthew was born in Saint John, New Brunswick, the son of George Frederic Matthew and Katherine (Diller) Matthew. His father was an amateur geologist and paleontologist who instilled his son with an abiding interest in the earth sciences. Matthew received an A.B. at the University of New Brunswick in 1889 and then earned his Ph.D. at Columbia University in 1894. Matthew was curator of the American Museum of Natural History from the mid-1890s to 1927, and director of the University of California Museum of Paleontology from 1927 to 1930. He was an elected member of the American Philosophical Society. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subfamily
In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zoological subfamily names with "-inae". Detarioideae is an example of a botanical subfamily. Detarioideae is a subdivision of the family Fabaceae (legumes), containing 84 genera. Stevardiinae is an example of a zoological subfamily. Stevardiinae is a large subdivision of the family Characidae, a diverse clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ... of freshwater fish. See also * International Code of Nomenclature for algae, fungi, and plants * International Code of Zoological Nomenclature * Rank (botany) * Rank (zoolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
