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Folivora
Sloths are a group of Neotropical xenarthran mammals constituting the suborder Folivora, including the extant 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 sloths ranging up to the size of elep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phyllophaga (mammal)
Sloths are a group of Neotropical xenarthran mammals constituting the suborder Folivora, including the extant 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 sloths ranging up to the size of ele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenarthra
Xenarthra (; from Ancient Greek ξένος, xénos, "foreign, alien" + ἄρθρον, árthron, "joint") is a 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 Mya, 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. Xenarthrans share several characteristics not present in other placental mammals, which suggest their ancestors were subterranean diggers for insects. The name Xenarthra de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pilosa
The order Pilosa is a clade of xenarthran placental mammals, native to the Americas. It includes the anteaters and sloths (which includes the extinct ground sloths). The name comes from the Latin word for "hairy". Origins and taxonomy The 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. A number of sloths were also formerly present on the Antilles, which they reached from South America by some combination of 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 characteristic of which is the presence of xenarthrals (extra formations between lumbar verte ... [...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] |
Scelidotheriidae
Scelidotheriidae is a family of extinct ground sloths within the order Pilosa, suborder Folivora and superfamily Mylodontoidea, related to the other extinct mylodontoid family, Mylodontidae, as well as to the living two-toed sloth family Choloepodidae. The only other extant family of the suborder Folivora is the distantly related Bradypodidae. Erected as the family Scelidotheriidae by Ameghino in 1889, the taxon was demoted to a subfamily by Gaudin in 1995. However, recent collagen sequence data indicates the group is less closely related to ''Mylodon'' and ''Lestodon'' than '' Choloepus'' is, and thus it has been elevated back to full family status by Presslee ''et al.'' (2019). Taxonomy Together with Mylodontidae, and the two-toed sloths, the scelidotheriids form the superfamily Mylodontoidea. ''Chubutherium'' is an ancestral and very plesiomorph In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nothrotheriidae
Nothrotheriidae is a family of extinct ground sloths that lived from approximately 17.5 mya—10,000 years ago, existing for approximately . Previously placed within the tribe Nothrotheriini or subfamily Nothrotheriinae within Megatheriidae, they are now usually placed in their own family, Nothrotheriidae. Nothrotheriids appeared in the Burdigalian, some 19.8 million years ago, in South America. The group includes the comparatively slightly built ''Nothrotheriops'', which reached a length of about . While nothrotheriids were small compared to some of their megatheriid relatives, their claws provided an effective defense against predators, like those of larger anteaters today. Evolution During the late Miocene and Pliocene, the sloth genus ''Thalassocnus'' of the west coast of South America became adapted to a shallow-water marine lifestyle. However, the family placement of ''Thalassocnus'' has been disputed; while long considered a nothrotheriid, one recent analysis moves it to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megatheriidae
Megatheriidae is a family of extinct ground sloths that lived from approximately 23 mya—11,000 years ago. Megatheriids appeared during the Late Oligocene (Deseadan in the SALMA classification), some 29 million years ago, in South America. The group includes the heavily built '' Megatherium'' (given its name 'great beast' by Georges Cuvier) and ''Eremotherium''. An early genus that was originally considered a megatheriid, the more slightly built ''Hapalops'', reached a length of about . The nothrotheres have recently been placed in their own family, Nothrotheriidae. The skeletal structure of these ground sloths indicates that the animals were massive. Their thick bones and even thicker joints (especially those on the hind legs) gave their appendages tremendous power that, combined with their size and fearsome claws, provided a formidable defense against predators. The earliest megatheriid in North America was ''Sibotherium'' which arrived 5.3 million years ago, after cros ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalocnidae
Megalocnidae is an extinct family of sloths, native to the islands of the Greater Antilles from the Early Oligocene to the Mid-Holocene. They are known from Cuba, Hispaniola and Puerto Rico, but are absent from Jamaica. While they were formerly placed in the Megalonychidae alongside two-toed sloths and ground sloths like ''Megalonyx'', recent mitochondrial DNA and collagen sequencing studies place them as the earliest diverging group basal to all other sloths. They displayed significant diversity in body size and lifestyle, with ''Megalocnus'' being terrestrial and probably weighing several hundred kilograms, while ''Neocnus'' was likely arboreal and similar in weight to extant tree sloths, at less than 10 kilograms. Origin It is thought that sloths arrived in the Caribbean from South America (where they arose) around the Eocene-Oligocene boundary about 33 million years ago, when there was a significant sea level drop caused by a glaciation episode. This has been associate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mylodontidae
Mylodontidae is a family of extinct South American and North American ground sloths within the suborder Folivora of order Pilosa The order Pilosa is a clade of xenarthran placental mammals, native to the Americas. It includes the anteaters and sloths (which includes the extinct ground sloths). The name comes from the Latin word for "hairy". Origins and taxonomy The b ..., living from around 23 million years ago (Mya) to 11,000 years ago. This family is most closely related to another family of extinct ground sloths, Scelidotheriidae, as well as to the extant arboreal two-toed sloths, family Choloepus, Choloepodidae; together these make up the superfamily Mylodontoidea. Phylogenetic analyses based on morphology uncovered the relationship between Mylodontidae and Scelidotheriidae; in fact, the latter was for a time considered a subfamily of mylodontids. However, molecular sequence comparisons were needed for the correct placement of Choloepodidae. These studies have been car ... [...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 Pleistocene. It is best known for the elephant-sized type species ''M. americanum'', sometimes called the giant ground sloth, or the megathere, native to the Pampas through southern Bolivia during the Pleistocene. Various other smaller species belonging to the subgenus ''Pseudomegatherium'' are known from the Andes. ''Megatherium'' is part of the sloth family Megatheriidae, which also includes the similarly giant ''Eremotherium'', comparable in size to ''M. americanum,'' which was native to tropical South America, Central America and North America as far north as the southern United States. Only a few other land mammals equaled or exceeded ''M. americanum'' in size, such as large proboscideans (e.g., elephants) and the giant rhinoceros ''Paraceratherium''. ''Megatherium'' was first discovered in 1788 on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anteater
Anteater is a common name for the four extant mammal species of 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 the sloths, they are within the order Pilosa. The name "anteater" is also commonly applied to the unrelated aardvark, numbat, echidnas, pangolins, and some members of the Oecobiidae, 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. Taxonomy Classification The anteaters are more closely related to the sloths than they are to any other group of mammals. Their next closest relations are armadillos. There are four extant species in three ... [...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] |
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