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Nodocephalosaurus Kirtlandensis
''Nodocephalosaurus'' (meaning "knob headed lizard") is a monotypic taxon, monospecific genus of ankylosauridae, ankylosaurid dinosaur from New Mexico that lived during the Late Cretaceous (late Campanian to early Maastrichtian stage, 73.49 to 73.04 Ma) in what is now the De-na-zin member of the Kirtland Formation. The type and only species, ''Nodocephalosaurus kirtlandensis'', is known only from a partial skull. It was named in 1999 by Robert M. Sullivan. ''Nodocephalosaurus'' has an estimated length of 4.5 metres (15 feet) and weight of 1.5 tonnes (3,306 lbs).Paul, G.S., 2016, ''The Princeton Field Guide to Dinosaurs 2nd Edition'', Princeton University Press It is closely related and shares similar cranial anatomy to ''Akainacephalus''. Discovery and naming In 1995, a partial skull of an ankylosauria, ankylosaur was discovered weathering out of a grey mudstone a few hundred metres west of a new ''Parasaurolophus'' site in the De-na-zin member of the Kirtland Formation, New Mex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Cretaceous
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harrisburg, Pennsylvania
Harrisburg is the capital city of the Commonwealth of Pennsylvania, United States, and the county seat of Dauphin County. With a population of 50,135 as of the 2021 census, Harrisburg is the 9th largest city and 15th largest municipality in Pennsylvania. Harrisburg is situated on the east bank of the Susquehanna River. It is the larger principal city of the Harrisburg–Carlisle metropolitan statistical area, also known as the Susquehanna Valley, which had a population of 591,712 as of 2020, making it the fourth most populous metropolitan area in Pennsylvania after the Philadelphia, Pittsburgh, and Lehigh Valley metropolitan areas. Harrisburg played a role in American history during the Westward Migration, the American Civil War, and the Industrial Revolution. During part of the 19th century, the building of the Pennsylvania Canal and later the Pennsylvania Railroad allowed Harrisburg to develop into one of the most industrialized cities in the Northeastern United States. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horn (anatomy)
A horn is a permanent pointed projection on the head of various animals that consists of a covering of keratin and other proteins surrounding a core of live bone. Horns are distinct from antlers, which are not permanent. In mammals, true horns are found mainly among the ruminant artiodactyls, in the families Antilocapridae (pronghorn) and Bovidae (cattle, goats, antelope etc.). Cattle horns arise from subcutaneous connective tissue (under the scalp) and later fuse to the underlying frontal bone. One pair of horns is usual; however, two or more pairs occur in a few wild species and in some domesticated breeds of sheep. Polycerate (multi-horned) sheep breeds include the Hebridean, Icelandic, Jacob, Manx Loaghtan, and the Navajo-Churro. Horns usually have a curved or spiral shape, often with ridges or fluting. In many species, only males have horns. Horns start to grow soon after birth and continue to grow throughout the life of the animal (except in pronghorns, which shed the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadratojugal Bone
The quadratojugal is a skull bone present in many vertebrates, including some living reptiles and amphibians. Anatomy and function In animals with a quadratojugal bone, it is typically found connected to the jugal (cheek) bone from the front and the squamosal bone from above. It is usually positioned at the rear lower corner of the cranium. Many modern tetrapods lack a quadratojugal bone as it has been lost or fused to other bones. Modern examples of tetrapods without a quadratojugal include salamanders, mammals, birds, and squamates (lizards and snakes). In tetrapods with a quadratojugal bone, it often forms a portion of the jaw joint. Developmentally, the quadratojugal bone is a dermal bone in the temporal series, forming the original braincase. The squamosal and quadratojugal bones together form the cheek region and may provide muscular attachments for facial muscles. In reptiles and amphibians In most modern reptiles and amphibians, the quadratojugal is a prominent, strapl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frontal Bone
The frontal bone is a bone in the human skull. The bone consists of two portions.''Gray's Anatomy'' (1918) These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bony part of the forehead, part of the bony orbital cavity holding the eye, and part of the bony part of the nose respectively. The name comes from the Latin word ''frons'' (meaning " forehead"). Structure of the frontal bone The frontal bone is made up of two main parts. These are the squamous part, and the orbital part. The squamous part marks the vertical, flat, and also the biggest part, and the main region of the forehead. The orbital part is the horizontal and second biggest region of the frontal bone. It enters into the formation of the roofs of the orbital and nasal cavities. Sometimes a third part is included as the nasal part of the frontal bone, and sometimes this is included with the squamous part. The nasal part is between the brow ridges, and ends in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bone
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Each has two surfaces and four borders. Structure The two nasal bones are joined at the midline internasal suture and make up the bridge of the nose. Surfaces The ''outer surface'' is concavo-convex from above downward, convex from side to side; it is covered by the procerus and nasalis muscles, and perforated about its center by a foramen, for the transmission of a small vein. The ''inner surface'' is concave from side to side, and is traversed from above downward, by a groove for the passage of a branch of the nasociliary nerve. Articulations The nasal articulates with four bones: two of the cranium, the frontal and ethmoid, and two of the face, the opposite nasal and the maxilla. Other animals In primitive bony fish and tetrapod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygon
In geometry, a polygon () is a plane figure that is described by a finite number of straight line segments connected to form a closed ''polygonal chain'' (or ''polygonal circuit''). The bounded plane region, the bounding circuit, or the two together, may be called a polygon. The segments of a polygonal circuit are called its '' edges'' or ''sides''. The points where two edges meet are the polygon's '' vertices'' (singular: vertex) or ''corners''. The interior of a solid polygon is sometimes called its ''body''. An ''n''-gon is a polygon with ''n'' sides; for example, a triangle is a 3-gon. A simple polygon is one which does not intersect itself. Mathematicians are often concerned only with the bounding polygonal chains of simple polygons and they often define a polygon accordingly. A polygonal boundary may be allowed to cross over itself, creating star polygons and other self-intersecting polygons. A polygon is a 2-dimensional example of the more general polytope in any number ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gregory S
Gregory may refer to: People and fictional characters * Gregory (given name), including a list of people and fictional characters with the given name * Gregory (surname), a surname Places Australia *Gregory, Queensland, a town in the Shire of Burke **Electoral district of Gregory, Queensland, Australia *Gregory, Western Australia. United States *Gregory, South Dakota *Gregory, Tennessee *Gregory, Texas Outer space *Gregory (lunar crater) *Gregory (crater on Venus) Other uses * "Gregory" (''The Americans''), the third episode of the first season of the television series ''The Americans'' See also * Greg (other) * Greggory * Gregoire (other) * Gregor (other) * Gregores (other) * Gregorian (other) * Gregory County (other) * Gregory Highway, Queensland * Gregory National Park, Northern Territory * Gregory River in the Shire of Burke, Queensland * Justice Gregory (other) Justice Gregory may refer to: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ziapelta
''Ziapelta'' is an extinct genus of ankylosaurid. Its fossils have been found in the Hunter Wash and De-na-zin members of the Kirtland Formation of Upper Cretaceous (Campanian) New Mexico. It was named in 2014, in a research paper led by ankylosaur researcher Victoria Arbour. There is a single species in the genus, ''Ziapelta sanjuanensis.'' The genus is named after the Zia sun symbol, a stylized sun with four groups of rays, having religious significance to the Zia people of New Mexico, and the iconic symbol on the state flag of New Mexico, and ''pelta'' (Latin), a small shield, in reference to the osteoderms found on all ankylosaurids. The specific name is in reference to San Juan County and the San Juan basin, where the fossils were found. Multiple specimens have been described to date, though the fossils are mostly from the front part of the animal. The adult length of ''Ziapelta'' is estimated at between and long, depending on whether the holotype was full-grown. It w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ahshislepelta
''Ahshislepelta'' (meaning "Ah-shi-sle-pah Wash shield") is a monotypic taxon, monospecific genus of ankylosauria, ankylosaur dinosaur from New Mexico that lived during the Late Cretaceous (late Campanian stage, 74.5 Ma) in what is now the Hunter Wash Member of the Kirtland Formation. The type and only species, ''Ahshislepelta minor'', is known only from an incomplete postcrania, postcranial skeleton of a small subadult or adult individual. It was named in 2011 in archosaur paleontology, 2011 by Michael Burns and Robert M. Sullivan. Based on the size of the humerus, ''Ahshislepelta'' is larger than ''Pinacosaurus, Pinacosaurus mephistocephalus'' but smaller than ''Talarurus'' and ''Pinacosaurus, Pinacosaurus grangeri''. Discovery and naming In 2005, a partial postcranial skeleton of an ankylosauria, ankylosaur was discovered from the Hunter Wash Member in the lower part of the Kirtland Formation, New Mexico at the Ah-shi-sle-pah Wilderness Study Area. The specimen was later colle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ankylosauridae
Ankylosauridae () is a family of armored dinosaurs within Ankylosauria, and is the sister group to Nodosauridae. The oldest known Ankylosaurids date to around 122 million years ago and went extinct 66 million years ago during the Cretaceous–Paleogene extinction event. These animals were mainly herbivorous and were obligate quadrupeds, with leaf-shaped teeth and robust, scute-covered bodies. Ankylosaurids possess a distinctly domed and short snout, wedge-shaped osteoderms on their skull, scutes along their torso, and a tail club. Ankylosauridae is exclusively known from the northern hemisphere, with specimens found in western North America, Europe, and East Asia. The first discoveries within this family were of the genus ''Ankylosaurus'', by Peter Kaiser and Barnum Brown in Montana in 1906. Brown went on to name Ankylosauridae and the subfamily Ankylosaurinae in 1908. Anatomy Ankylosaurids are stout, solidly built, armoured dinosaurs. They possess accessory ossifications on c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Finish
Surface finish, also known as surface texture or surface topography, is the nature of a surface as defined by the three characteristics of lay, surface roughness, and waviness.. It comprises the small, local deviations of a surface from the perfectly flat ideal (a true plane). Surface texture is one of the important factors that control friction and transfer layer formation during sliding. Considerable efforts have been made to study the influence of surface texture on friction and wear during sliding conditions. Surface textures can be isotropic or anisotropic. Sometimes, stick-slip friction phenomena can be observed during sliding, depending on surface texture. Each manufacturing process (such as the many kinds of machining) produces a surface texture. The process is usually optimized to ensure that the resulting texture is usable. If necessary, an additional process will be added to modify the initial texture. The latter process may be grinding (abrasive cutting), polishing, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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