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Megalonyx
''Megalonyx'' (Greek, "large claw") is an extinct genus of ground sloths of the family Megalonychidae, native to North America during the Pliocene and Pleistocene epochs. It became extinct during the Quaternary extinction event at the end of the Rancholabrean of the Pleistocene, living from ~5 million to 11,000 years ago. The type species, ''M. jeffersonii'', measured about and weighed up to . ''Megalonyx'' is descended from ''Pliometanastes,'' a genus of ground sloth that had arrived in North America during the Late Miocene, prior to the Great American Biotic Interchange. ''Megalonyx'' had the widest distribution of any North American ground sloth, having a range encompassing most of the contiguous United States, extending as far north as Alaska during warm periods. Taxonomy In 1796, Colonel John Stuart sent Thomas Jefferson, shortly before he took office as Vice President of the United States, some fossil bones: a femur fragment, ulna, radius, and foot bones including three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalonyx CasparWistar Claw Griffe1799
''Megalonyx'' (Greek, "large claw") is an extinct genus of ground sloths of the family Megalonychidae, native to North America during the Pliocene and Pleistocene epochs. It became extinct during the Quaternary extinction event at the end of the Rancholabrean of the Pleistocene, living from ~5 million to 11,000 years ago. The type species, ''M. jeffersonii'', measured about and weighed up to . ''Megalonyx'' is descended from ''Pliometanastes,'' a genus of ground sloth that had arrived in North America during the Late Miocene, prior to the Great American Biotic Interchange. ''Megalonyx'' had the widest distribution of any North American ground sloth, having a range encompassing most of the contiguous United States, extending as far north as Alaska during warm periods. Taxonomy In 1796, Colonel John Stuart sent Thomas Jefferson, shortly before he took office as Vice President of the United States, some fossil bones: a femur fragment, ulna, radius, and foot bones including three ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalonychidae
Megalonychidae is an extinct family of sloths including the extinct ''Megalonyx''. Megalonychids first appeared in the early Oligocene, about 35 million years (Ma) ago, in southern Argentina (Patagonia). There is actually one possible find dating to the Eocene, about 40 Ma ago, on Seymour Island in Antarctica (which was then still connected to South America). They first reached North America by island-hopping across the Central American Seaway, about 9 million years ago, prior to formation of the Isthmus of Panama about 2.7 million years ago (which led to the main pulse of the Great American Interchange). Some megalonychid lineages increased in size as time passed. The first species of these were small and may have been partly tree-dwelling, whereas the Pliocene (about 5 to 2 million years ago) species were already approximately half the size of the huge Late Pleistocene ''Megalonyx jeffersonii'' from the last ice age.J.L. White (1993) It was formerly believed, based on morpholo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Sloth
Ground sloths are a diverse group of extinct sloths in the mammalian superorder Xenarthra. The term is used to refer to all extinct sloths because of the large size of the earliest forms discovered, compared to existing tree sloths. The Caribbean ground sloths, the most recent survivors, lived in the Antilles, possibly until 1550 BCE. However, radiocarbon dating suggests an age of between 2819 and 2660 BCE for the last occurrence of ''Megalocnus'' in Cuba. Ground sloths had been extinct on the mainland of North and South America for 10,000 years or more. They survived 5,000–6,000 years longer in the Caribbean than on the American mainland, which correlates with the later colonization of this area by humans. Much ground sloth evolution took place during the late Paleogene and Neogene of South America, while the continent was isolated. At their earliest appearance in the fossil record, the ground sloths were already distinct at the family level. The presence ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great American Biotic Interchange
The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land and freshwater fauna migrated from North America via Central America to South America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor and bridged the formerly separated continents. Although earlier dispersals had occurred, probably over water, the migration accelerated dramatically about 2.7 million years ( Ma) ago during the Piacenzian age. It resulted in the joining of the Neotropic (roughly South American) and Nearctic (roughly North American) biogeographic realms definitively to form the Americas. The interchange is visible from observation of both biostratigraphy and nature (neontology). Its most dramatic effect is on the zoogeography of mammals, but it also gave an opportunity for reptiles, amphibians, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
West Virginia
West Virginia is a state in the Appalachian, Mid-Atlantic and Southeastern regions of the United States.The Census Bureau and the Association of American Geographers classify West Virginia as part of the Southern United States while the Bureau of Labor Statistics classifies the state as a part of the Mid-Atlantic regionMid-Atlantic Home : Mid-Atlantic Information Office: U.S. Bureau of Labor Statistics" www.bls.gov. Archived. It is bordered by Pennsylvania to the north and east, Maryland to the east and northeast, Virginia to the southeast, Kentucky to the southwest, and Ohio to the northwest. West Virginia is the 10th-smallest state by area and ranks as the 12th-least populous state, with a population of 1,793,716 residents. The capital and largest city is Charleston. West Virginia was admitted to the Union on June 20, 1863, and was a key border state during the American Civil War. It was the only state to form by separating from a Confederate state, the second to sepa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Stuart (Virginia Settler)
Colonel John Stuart (17 March 1749 in Augusta County, Virginia – 18 August 1823 in Greenbrier County, Virginia ow West Virginia was a Revolutionary War commander and pioneering western Virginia settler. A veteran of the Battle of Point Pleasant (1774), he surveyed and settled the Greenbrier Valley and is known locally as the "Father of Greenbrier County". Owing to his ''Memoir of Indian Wars and Other Occurrences'', written in 1799, he has been called "the most important chronicler of pioneer history in southern West Virginia". Biography Stuart's father, the Scotsman David Stuart, was among the supporters of Charles Edward Stuart ("Bonnie Prince Charlie") as king of Great Britain. Soon after the failure of the Prince's cause at Culloden (1746) David found it necessary to immigrate to America. He settled in Augusta County, Virginia on the Shenandoah River, some distance from the town of Staunton. At the age of twenty, John Stuart was a member of the 1769 survey by citizen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Extinction Event
The Quaternary period (from 2.588 ± 0.005 million years ago to the present) has seen the extinctions of numerous predominantly megafaunal species, which have resulted in a collapse in faunal density and diversity and the extinction of key ecological strata across the globe. The most prominent event in the Late Pleistocene is differentiated from previous Quaternary pulse extinctions by the widespread absence of ecological succession to replace these extinct species, and the regime shift of previously established faunal relationships and habitats as a consequence. The earliest casualties were incurred at 130,000 BCE (the start of the Late Pleistocene), in Australia ~ 60,000 years ago, in Americas ~ 15,000 years ago, coinciding in time with the early human migrations. However, the great majority of extinctions in Afro-Eurasia and the Americas occurred during the transition from the Pleistocene to the Holocene epoch (13,000 BCE to 8,000 BCE). This extinction wave di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliometanastes
''Pliometanastes'' is an extinct genus of ground sloths of the family Megalonychidae endemic to North America during the Late Miocene epoch through very early Pliocene epoch (Hemphillian in the NALMA classification). Its fossils have been found in Costa Rica and across the southern United States from California to Florida. Description ''Pliometanastes'' and ''Thinobadistes'' were the first of the giant sloths to appear in North America, the former around 9 million years ago. Both were in North America before the Panamanian Land Bridge formed around 2.7 million years ago, which led to the main pulse of the Great American Interchange. It is then reasonable to presume that the ancestors of ''Pliometanastes'' island-hopped across the Central American Seaway from South America, where ground sloths arose. ''Pliometanastes'' gave rise to ''Megalonyx''. Their closest extant relatives, based on molecular results (which clash with earlier conclusions derived from morphology) are the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radius (bone)
The radius or radial bone is one of the two large bones of the forearm, the other being the ulna. It extends from the lateral side of the elbow to the thumb side of the wrist and runs parallel to the ulna. The ulna is usually slightly longer than the radius, but the radius is thicker. Therefore the radius is considered to be the larger of the two. It is a long bone, prism-shaped and slightly curved longitudinally. The radius is part of two joints: the elbow and the wrist. At the elbow, it joins with the capitulum of the humerus, and in a separate region, with the ulna at the radial notch. At the wrist, the radius forms a joint with the ulna bone. The corresponding bone in the lower leg is the fibula. Structure The long narrow medullary cavity is enclosed in a strong wall of compact bone. It is thickest along the interosseous border and thinnest at the extremities, same over the cup-shaped articular surface (fovea) of the head. The trabeculae of the spongy tissue are some ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Femur
The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with the tibia (shinbone) and patella (kneecap), forming the knee joint. By most measures the two (left and right) femurs are the strongest bones of the body, and in humans, the largest and thickest. Structure The femur is the only bone in the upper leg. The two femurs converge medially toward the knees, where they articulate with the proximal ends of the tibiae. The angle of convergence of the femora is a major factor in determining the femoral-tibial angle. Human females have thicker pelvic bones, causing their femora to converge more than in males. In the condition ''genu valgum'' (knock knee) the femurs converge so much that the knees touch one another. The opposite extreme is ''genu varum'' (bow-leggedness). In the general populatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greenbrier County, West Virginia
Greenbrier County () is a county in the U.S. state of West Virginia. As of the 2020 census, the population was 32,977. Its county seat is Lewisburg. The county was formed in 1778 from Botetourt and Montgomery counties in Virginia. History Prior to the arrival of European-American settlers around 1740, Greenbrier County, like most of West Virginia, was used as a hunting ground by the Shawnee and Cherokee nations. They called this land ''Can-tuc-kee''. Shawnee leaders, including Pucksinwah and later his son Tecumseh, were alarmed by the arrival of the European settlers, who by 1771 had set up extensive trade in the area. The day books of early merchants Sampson and George Mathews recorded sales to the Shawnee that included such luxury items as silk, hats, silver, and tailor-made suits.Handley, Harry E. (1963), "The Mathews Trading Post", published in ''The Journal of the Greenbrier Historical Society'': Volume 1, Number 1 (Lewisburg, West Virginia: Greenbrier Historical Soc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vice President Of The United States
The vice president of the United States (VPOTUS) is the second-highest officer in the executive branch of the U.S. federal government, after the president of the United States, and ranks first in the presidential line of succession. The vice president is also an officer in the legislative branch, as the president of the Senate. In this capacity, the vice president is empowered to preside over Senate deliberations at any time, but may not vote except to cast a tie-breaking vote. The vice president is indirectly elected together with the president to a four-year term of office by the people of the United States through the Electoral College. The modern vice presidency is a position of significant power and is widely seen as an integral part of a president's administration. While the exact nature of the role varies in each administration, most modern vice presidents serve as a key presidential advisor, governing partner, and representative of the president. The vice president ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
