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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] |
Eremotherium
''Eremotherium'' (from Greek for "steppe" or "desert beast": ἔρημος "steppe or desert" and θηρίον "beast") is an extinct genus of giant ground sloth, in the family Megatheriidae, the largest and most heavily built family of sloths. ''Eremotherium'' lived in the southern parts of North America and the northern parts of South America from the Pliocene, around 5.3 million years ago, to the end of the Late Pleistocene, around 10,000 years ago. ''Eremotherium'' was widespread in tropical and subtropical lowlands and lived there in partly open and closed landscapes, while its close relative ''Megatherium'' lived in more temperate climes. Both genera reached the size of today's elephants and were among the largest mammals in the Americas. Characteristic of ''Eremotherium'' was its robust physique with comparatively long limbs and front and hind feet especially for later representatives- three fingers. However, the skull is relatively gracile, the teeth are uniform and high ... [...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] |
Megatheriinae
Megatheriinae is a subfamily of the Megatheriidae, an extinct family of ground sloths that lived from the Middle Miocene to the Early Holocene. Classification Within the Megatheriidae there are two (possibly three) subfamilies; the Megatheriinae and the Planopsinae. The phylogenetically older group is represented by the Planopsinae from the Lower and Middle Miocene. These still possessed a caniniform anterior tooth, which was separated from the posterior molar-like teeth by a small diastema . The more derived Megatheriinae, which are known from the Middle Miocene to the Early Holocene, on the other hand, had fully homodontic molars in a closed row. Originally, the subfamilies of the Nothrotheriinae and the Schismotheriinae were also placed in the Megatheriidae. Based on skull studies, the Nothrotheriidae, in which, among other genera, ''Nothrotherium'', ''Nothrotheriops,'' and the semiaquatic ''Thalassocnus ''Thalassocnus'' is an extinct genus of semiaquatic ground sloths from ... [...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] |
Ground Sloth (skull)
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 pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalassocnus
''Thalassocnus'' is an extinct genus of semiaquatic ground sloths from the Miocene and Pliocene of the Pacific South American coast. It is monotypic within the subfamily Thalassocninae. The five species—''T. antiquus'', ''T. natans'', ''T. littoralis'', ''T. carolomartini'', and ''T. yuacensis''—represent a chronospecies, a population gradually adapting to marine life in one direct lineage. They are the only known aquatic sloths, but they may have also been adapted to a terrestrial lifestyle. They have been found in the Pisco Formation of Peru, the Tafna Formation of Argentina, and the Bahía Inglesa, Coquimbo, and Horcón formations of Chile. Thalassocninae has been placed in both the families Megatheriidae and Nothrotheriidae. ''Thalassocnus'' evolved several marine adaptations over the course of 4 million years, such as dense and heavy bones to counteract buoyancy, the internal nostrils migrating farther into the head to help with breathing while completely submerged, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground Sloth (hand)
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 pre ... [...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] |
Sibotherium
''Sibotherium'' is an extinct genus of ground sloth in the family Megatheriidae that lived in what is now Costa Rica during the Late Miocene. It was a large ground sloth, weighing more than 2,500 kg. Discovery Fossils of ''Sibotherium'' have been found in the Curré Formation in the Puntarenas Province of Costa Rica. The finds are 5.8 million years old and date to the Late Hemphillian, falling within the Late Miocene. The holotype is a left ankle bone. Skeletal parts of some individuals of ''Sibotherium'' have also been found, namely partial mandibles, molars, a collarbone and parts of the legs, hands and feet. Etymology The genus name, ''Sibotherium'' is derived from ''Sibö'', the good creator in Bribri mythology, and ''therion'', Greek for "beast". In the beginning Sibö made the Earth, the land, the animals and the plants according to the myths of the Bribri, the original inhabitants of southern Costa Rica. This name was chosen because ''Sibotherium'' was one of the fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prepoplanops
''Prepoplanops'' is an extinct genus of ground sloth of the family Megatheriidae. It lived in the Miocene around 18 to 16 million years ago of what is now Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th .... The only known species is ''Prepoplanops boleadorensis''. Description ''Prepoplanops'' was a medium-sized ground sloth, about 1.5 to 2 meters long. Classification ''Prepoplanops'' was a representative of the Planopsinae, a subfamily of megatheriids that lived during the Miocene. In particular, it appears that ''Prepoplanops'' was an intermediate form between ''Planops'' and ''Prepotherium''. ''Prepoplanops boleadorensis'' was first described in 2013, based on fossil remains found in Argentina's Santa Cruz Province in the Cerro Boleadoras Formation. Below is a phyl ... [...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 Mya (unit), 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 measure 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 paleogeography, paleogeographic timeline of South ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bone
A bone is a Stiffness, rigid Organ (biology), organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red blood cell, red and white blood cells, store minerals, provide structure and support for the body, and enable animal locomotion, mobility. Bones come in a variety of shapes and sizes and have complex internal and external structures. They are lightweight yet strong and hard and serve multiple Function (biology), functions. Bone tissue (osseous tissue), which is also called bone in the mass noun, uncountable sense of that word, is hard tissue, a type of specialized connective tissue. It has a honeycomb-like matrix (biology), matrix internally, which helps to give the bone rigidity. Bone tissue is made up of different types of bone cells. Osteoblasts and osteocytes are involved in the formation and mineralization (biology), mineralization of bone; osteoclasts are involved in the bone resorption, resor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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