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Lujanian
The Lujanian age is a South American land mammal age within the Pleistocene and Holocene epochs of the Neogene, from 0.8–0.011 Mya (unit), Ma or 800–11 tya (unit), tya. It follows the Ensenadan. The age is usually divided into the middle Pleistocene Bonaerian stage, which ends at about 130,000 years, and the Lujanian, which lasts from about 130,000 years into the early Holocene. The latter Lujanian stage overlaps chronologically with the North American Irvingtonian and Rancholabrean. Fauna include Ground sloth, ground sloths, Litopterna, litopterns, Arctotherium, short-faced bears, South American horse ''Amerhippus'' and Cingulata, cingulates such as Glyptodont, glyptodonts and the armadillo-like ''Pachyarmatherium''. References Lujanian, Pleistocene life Holocene Quaternary animals of South America {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctotherium
''Arctotherium'' ("bear beast") is an extinct genus of the Pleistocene Tremarctinae, short-faced bears endemic to Central America, Central and South America. ''Arctotherium'' migrated from North America to South America during the Great American Interchange, following the formation of the Isthmus of Panama during the late Pliocene. Evolution Tremarctinae ''Arctotherium'' is part of the Tremarctinae subfamily of bears, otherwise known as the Tremarctinae, short faced bears, which also includes ''Arctodus'' (North American short faced bears) and ''Tremarctos'' (the Tremarctos floridanus, Floridian and modern spectacled bear). Tremarctinae originate with their common ancestor, ''Plionarctos,'' in the Hemphillian, Middle Hemphillian (earliest Late Miocene, ~10 Ma) of North America; ''Plionarctos'' is last recorded in the Blancan, early Blancan (Early Pliocene, ~3.3 Ma). Around the Late Miocene, Miocene-Zanclean, Pliocene boundary (~5 Ma) Tremarctinae, Tremarctines, along with other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lujanian
The Lujanian age is a South American land mammal age within the Pleistocene and Holocene epochs of the Neogene, from 0.8–0.011 Mya (unit), Ma or 800–11 tya (unit), tya. It follows the Ensenadan. The age is usually divided into the middle Pleistocene Bonaerian stage, which ends at about 130,000 years, and the Lujanian, which lasts from about 130,000 years into the early Holocene. The latter Lujanian stage overlaps chronologically with the North American Irvingtonian and Rancholabrean. Fauna include Ground sloth, ground sloths, Litopterna, litopterns, Arctotherium, short-faced bears, South American horse ''Amerhippus'' and Cingulata, cingulates such as Glyptodont, glyptodonts and the armadillo-like ''Pachyarmatherium''. References Lujanian, Pleistocene life Holocene Quaternary animals of South America {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South American Land Mammal Age
The South American land mammal ages (SALMA) establish a geologic timescale for prehistoric South American fauna beginning 64.5 Ma during the Paleocene and continuing through to the Late Pleistocene (0.011 Ma). These periods are referred to as ages, stages, or intervals and were established using geographic place names where fossil materials where obtained.Flynn & Swisher, 1995 The basic unit of measurement is the first/last boundary statement. This shows that the first appearance event of one taxon is known to predate the last appearance event of another. If two taxa are found in the same fossil quarry or at the same stratigraphic horizon, then their age-range zones overlap. Background South America was an island continent for much of the Cenozoic, or the "Age of Mammals". As a result, its mammals evolved in their own unique directions, as Australia and Madagascar still have today. Paleogeographic timeline A simplified paleogeographic timeline of South America: * 66 Ma – ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachyarmatherium
''Pachyarmatherium'' is a genus of extinct large armadillo-like cingulates found in North and South America from the Pliocene and Pleistocene epochs, related to the extant armadillos and the extinct pampatheres and glyptodonts. It was present from 4.9 Mya to 11,000 years ago, existing for approximately . Taxonomy ''Pachyarmatherium'' was named by Downing and White (1995). Its type is ''P. leiseyi''. It was assigned to Dasypodoidea by Downing and White (1995), and tentatively to Glyptodontidae by McKenna and Bell (1997). A cladistic analysis performed by de O. Porpino et al. (2009) led to the conclusion that ''Pachyarmatherium'' is a sister group to a clade consisting of Glyptodontidae and Pampatheriidae. Oliveira et al. (2013) suggest that ''Pachyarmatherium'' is a possible dasypodid. Fossil distribution of ''Pachyarmatherium'' ''P. leiseyi'' * Kissimmee River site, Tamiami Formation, Okeechobee County, Florida ~4.9—1.8 Mya. * Haile 16A Site, Alachua County, Fl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amerhippus
''Equus neogeus'' is an extinct species of equine native to South America during the Pleistocene. It was formerly thought to be several distinct species within the subgenus ''Amerhippus'', but was later shown to be a single morphologically variable species. It is thought to be closely related to true horses. Taxonomy While they have formerly been referred to as belonging to 5 separate species, this has been revised down into three, and more recently a single, morphologically variable species ''Equus neogeus''. Some authors continue to recognise three species, restricting ''Equus neogeus'' to large-sized individuals spanning from the Pampas to Northeast Brazil, while separating the smaller ''Equus andium'' for populations in the northern-central Andes, and ''Equus insulatus'' for medium-sized animals spanning from Bolivia to Venezuela. These authors suggest that ''E. insulatus'' was the ancestor of the other species. Historically, South American ''Equus'' species were placed in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glyptodont
Glyptodonts are an extinct clade of large, heavily armoured armadillos, reaching up to in height, and maximum body masses of around 2 tonnes. They had short, deep skulls, a fused vertebral column, and a large bony carapace made up of hundreds of individual scutes. Some glyptodonts had Tail club, clubbed tails, similar to Ankylosauridae, ankylosaurid dinosaurs. The earliest widely recognised fossils of glyptodonts in South America are known from the late Eocene, around 38 million years ago, and they spread to southern North America after the continents became connected around 2.7 million years ago. The best-known genus within the group is ''Glyptodon.'' Glyptodonts were historically considered to constitute the distinct family Glyptodontidae, with their relationships to modern armadillos being contested. In 2016, an analysis of the mitochondrial genome of ''Doedicurus'' found that it was, in fact, nested within the modern armadillos as the sister group of a clade consisting of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Sloth
Ground sloths are a diverse group of extinct sloths in the mammalian superorder Xenarthra. They varied widely in size with the largest, belonging to genera '' Lestodon'', ''Eremotherium'' and ''Megatherium'', being around the size of elephants. Ground sloths represent a paraphyletic group, as living tree sloths are thought to have evolved from ground sloth ancestors. The early evolution of ground sloths took place during the late Paleogene and Neogene of South America, while the continent was isolated. At their earliest appearance in the fossil record, they were already distinct at the family level. Sloths dispersed into the Greater Antilles during the Oligocene, and the presence of intervening islands between the American continents in the Miocene allowed a dispersal of some species into North America. They were hardy as evidenced by their high species diversity and their presence in a wide variety of environments, extending from the far south of Patagonia ( Cueva del Milodón ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rancholabrean
The Rancholabrean North American Land Mammal Age on the geologic timescale is a North American faunal stage in the North American Land Mammal Ages chronology (NALMA),Sanders, A.E., R.E. Weems, and L.B. Albright III (2009) Formalization of the mid-Pleistocene "Ten Mile Hill beds" in South Carolina with evidence for placement of the Irvingtonian–Rancholabrean boundary, ''Museum of Northern Arizona Bulletin'' 64:369-375 named after the famed Rancho La Brea fossil site (more commonly known as the La Brea tar pits) in Los Angeles, California.Savage, D.E. (1951) Late Cenozoic vertebrates of the San Francisco Bay region, ''University of California Publications, Bulletin of the Department of Geological Sciences'' 28:215-314 The Rancholabrean is characterized by the presence of the genus ''Bison,'' which appeared in northwestern North America during the Illinoian (globally known as the Penultimate Glacial Period or Marine Isotope Stage 6) around 190-130,000 years ago, before becoming es ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irvingtonian
The Irvingtonian North American Land Mammal Age on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), spanning from 1.8 million – 250,000 years Before Present, BP.The _Blancan, Irvingtonian and Rancholabrean Mammal Ages by Christopher J. Bell and Ernest L. Lundelius Jr., Anthony D. Barnosky, Russell W. Graham, Everett H. Lindsay, Dennis R. Ruez Jr., Holmes A. Semken Jr., S. David Webb, and Richard J. Zakrzewski. January 2004 in the book: Late Cretaceous and Cenozoic Mammals of North America: Biostratigraphy and Geochronology. Chapter: 7. Publisher: Columbia University Press; Editors: Michael O. Woodburne. pp274-276 Named after an assemblage of fossils from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ensenadan
The Ensenadan age is a period of geologic time (1.2–0.8 Ma) within the Early Pleistocene epoch of the Quaternary used more specifically with South American Land Mammal Ages. It follows the Uquian and precedes the Lujanian The Lujanian age is a South American land mammal age within the Pleistocene and Holocene epochs of the Neogene, from 0.8–0.011 Mya (unit), Ma or 800–11 tya (unit), tya. It follows the Ensenadan. The age is usually divided into the middle Pleist ... age. References Pleistocene life Calabrian (stage) Quaternary animals of South America .001Ensenadan {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene Life
The Pleistocene ( ; referred to colloquially as the ''Ice Age'') is the geological epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold glacial periods and warmer interglacials, with the sea levels being up to lower than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
