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Xenarthrans
Xenarthra (; from Ancient Greek ξένος, xénos, "foreign, alien" + ἄρθρον, árthron, "joint") is a superorder and major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and armadillos. Extinct xenarthrans include the glyptodonts, pampatheres and ground sloths. Xenarthrans originated in South America during the late Paleocene about 60 million years ago. They evolved and diversified extensively in South America during the continent's long period of isolation in the early to mid Cenozoic Era. They spread to the Antilles by the early Miocene and, starting about 3 million years ago, spread to Central and North America as part of the Great American Interchange. Nearly all of the formerly abundant megafaunal xenarthrans became extinct at the end of the Pleistocene. Characteristics Xenarthrans share several characteristics that are not present in other placental mammals, which suggest that xenarthrans descend from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great American 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 (animals), fauna migrated from North America to South America via Central America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor, forming a land bridge between the previously separated continents. Although earlier dispersals had occurred, probably over water, the migration accelerated dramatically about 2.7 million years (Ma (unit), Ma) ago during the Piacenzian age. It resulted from the joining of the Neotropical realm, Neotropic (roughly South American) and Nearctic realm, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megatherium
''Megatherium'' ( ; from Greek () 'great' + () 'beast') is an extinct genus of ground sloths endemic to South America that lived from the Early Pliocene through the end of the Late Pleistocene. It is best known for the elephant-sized type species ''Megatherium americanum'', primarily known from the Pampas, but ranging southwards to northernmost Patagonia and northwards to southern Bolivia during the late Middle Pleistocene and Late Pleistocene. Various other species belonging to the subgenus ''Pseudomegatherium'' ranging in size comparable to considerably smaller than ''M. americanum'' are known from the Andean region. The first (holotype) specimen of ''Megatherium'' was discovered in 1787 on the bank of the Luján River in what is now northern Argentina. The specimen was then shipped to Spain the following year wherein it caught the attention of the French paleontologist Georges Cuvier, who named the animal in 1796 and was the first to determine, by means of comparative anato ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giant Anteater
The giant anteater (''Myrmecophaga tridactyla'') is an Insectivore, insectivorous mammal native to Central America, Central and South America. It is the largest of the four living species of anteaters, which are classified with sloths in the order (biology), order Pilosa. The only extant member of the genus ''Myrmecophaga'', the giant anteater is mostly terrestrial, in contrast to other living anteaters and sloths, which are arboreal or semiarboreal. The species is in length, with weights of for males and for females. It is recognizable by its elongated snout, bushy tail, long foreclaws, and distinctively colored fur. The giant anteater is found in multiple habitats, including grassland and rainforest. It forages in open areas and rests in more forested habitats. It feeds primarily on ants and termites, using its foreclaws to dig them up and its long, sticky tongue to collect them. Though giant anteaters live in overlapping home ranges, they are mostly solitary except during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Folivora
Sloths are a Neotropical realm, Neotropical group of xenarthran mammals constituting the suborder Folivora, including the extant Arboreal locomotion, arboreal tree sloths and extinct terrestrial ground sloths. Noted for their slowness of movement, tree sloths spend most of their lives hanging upside down in the trees of the tropical rainforests of South America and Central America. Sloths are considered to be most closely related to anteaters, together making up the xenarthran order Pilosa. There are six extant sloth species in two genera – ''Bradypus'' (three-toed sloths) and ''Choloepus'' (two-toed sloths). Despite this traditional naming, all sloths have three toes on each rear limb – although two-toed sloths have only two digits on each forelimb. The two groups of sloths are from different, distantly related families, and are thought to have evolved their morphology via parallel evolution from terrestrial ancestors. Besides the extant species, many species of ground sl ... [...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] |
Vermilingua
Anteaters are the four extant mammal species in the suborder Vermilingua (meaning "worm tongue"), commonly known for eating ants and termites. The individual species have other names in English and other languages. Together with sloths, they are within the order Pilosa. The name "anteater" is also commonly applied to the aardvark, numbat, echidnas, and pangolins, although they are not closely related to them. Extant species are the giant anteater ''Myrmecophaga tridactyla'', about long including the tail; the silky anteater ''Cyclopes didactylus'', about long; the southern tamandua or collared anteater ''Tamandua tetradactyla'', about long; and the northern tamandua ''Tamandua mexicana'' of similar dimensions. Etymology The name ''anteater'' refers to the species' diet, which consists mainly of ants and termites. Anteater has also been used as a common name for a number of animals that are not in Vermilingua, including the echidnas, numbat, pangolins, and aardvark. Antea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pilosa
The Order (biology), order Pilosa is a clade of xenarthran placental mammals, native to the Americas. It includes anteaters and sloths (which include the extinct ground sloths). The name comes from the Latin word for "hairy". Origins and taxonomy The Biogeography, biogeographic origins of the Pilosa are still unclear, but they can be traced back in South America as far as the early Paleogene (about 60 million years ago, only a short time after the end of the Mesozoic Era). The presence of these animals in Central America and their former presence in North America is a result of the Great American Interchange. Pilosans of the Caribbean, A number of sloths were also formerly present on the Greater Antilles, Antilles, which they reached from South America by some combination of oceanic dispersal, rafting or floating with the prevailing currents. Together with the armadillos, which are in the order Cingulata, pilosans are part of the larger superorder Xenarthra, a defining charact ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Extinction Event
The Late Pleistocene to the beginning of the Holocene saw the extinction of the majority of the world's megafauna, typically defined as animal species having body masses over , which resulted in a collapse in faunal density and diversity across the globe. The extinctions during the Late Pleistocene are differentiated from previous extinctions by their extreme size bias towards large animals (with small animals being largely unaffected), and widespread absence of ecological succession to replace these extinct megafaunal species, and the regime shift of previously established faunal relationships and habitats as a consequence. The timing and severity of the extinctions varied by region and are generally thought to have been driven by humans, climatic change, or a combination of both. Human impact on megafauna populations is thought to have been driven by hunting ("overkill"), as well as possibly environmental alteration. The relative importance of human vs climatic factors in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
