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Notoungulates
Notoungulata is an extinct order of ungulates that inhabited South America from the early Paleocene to the end of the Pleistocene, living from approximately 61 million to 11,000 years ago. Notoungulates were morphologically diverse, with forms resembling animals as disparate as rabbits and rhinoceroses. Notoungulata are the largest group of South American native ungulates, with over 150 genera in 14 families having been described, divided into two major subgroupings, Typotheria and Toxodontia. Notoungulates first diversified during the Eocene. Their diversity declined from the late Neogene onwards, with only the large toxodontids persisting until the end of the Pleistocene (with ''Mixotoxodon'' expanding into Central America and southern North America), perishing as part of the Late Pleistocene megafauna extinctions along with most other large mammals across the Americas. Collagen sequence analysis suggests that notoungulates are closely related to litopterns, another group of So ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxodon
''Toxodon'' (meaning "bow tooth" in reference to the curvature of the teeth) is an extinct genus of large ungulate native to South America from the Pliocene to the end of the Late Pleistocene. ''Toxodon'' is a member of Notoungulata, an order of extinct South American native ungulates distinct from the two living ungulate orders that had been indigenous to the continent for over 60 million years since the early Cenozoic, prior to the arrival of living ungulates into South America around 2.5 million years ago during the Great American Interchange. ''Toxodon'' is a member of the family Toxodontidae, which includes medium to large sized herbivores. ''Toxodon'' was one of the largest members of Toxodontidae and Notoungulata, with ''Toxodon platensis'' having an estimated body mass of . Remains of ''Toxodon'' were first collected by Charles Darwin during the voyage of the Beagle in 1832-33, and later scientifically named by Richard Owen in 1837. Both Darwin and Owen were puzzled by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henricosborniidae
Henricosborniidae is a family of extinct notoungulate mammals known from the Late Paleocene to Middle Eocene of Argentina, Bolivia and Brazil. The name honors U.S. paleontologist Henry Fairfield Osborn. Description Henricosborniidae is a group of primitive notoungulates assigned to the suborder Notioprogonia together with Notostylopidae, not because these two families share any derived features, but because they do not clearly belong to any other clade. The henricosborniids are only known from the late Paleocene and early Eocene (Itaboraian-Casamayoran SALMA, ), making them slightly older and more primitive than the notostylopids. The henricosborniid dentition is the most generalized and primitive of all notoungulates, and they are believed to be near the source of all notoungulates. They have low teeth crowns and the dental formula . George Gaylord Simpson noted that many of the mammals that Ameghino had, and Simpson himself did, describe from the Río Chico Formation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notostylopidae
Notostylopidae is an extinct family comprising five genera of notoungulate mammals known from the Late Paleocene (Riochican) to Early Oligocene (Tinguirirican) of Argentina, Brazil and Chile in South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level.'' Columbia University Press, New York, 631 pp. References Notoungulates Prehistoric mammal families Paleogene mammals of South America Eocene first appearances Rupelian extinctions Taxa named by Florentino Ameghino {{notoungulate-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Collagen
Collagen () is the main structural protein in the extracellular matrix of the connective tissues of many animals. It is the most abundant protein in mammals, making up 25% to 35% of protein content. Amino acids are bound together to form a triple helix of elongated fibril known as a collagen helix. It is mostly found in cartilage, bones, tendons, ligaments, and skin. Vitamin C is vital for collagen synthesis. Depending on the degree of biomineralization, mineralization, collagen tissues may be rigid (bone) or compliant (tendon) or have a gradient from rigid to compliant (cartilage). Collagen is also abundant in corneas, blood vessels, the Gut (anatomy), gut, intervertebral discs, and the dentin in teeth. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes 1% to 2% of muscle tissue and 6% by weight of skeletal muscle. The fibroblast is the most common cell creating collagen in animals. Gelatin, which is used in food and industry, is collagen t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litoptern
Litopterna (from "smooth heel") is an extinct order of South American native ungulates that lived from the Paleocene to the Pleistocene-Holocene around 62.5 million to 12,000 years ago (or possibly as late as 3,500 years ago), and were also present in Antarctica during the Eocene. They represent the second most diverse group of South American ungulates after Notoungulata. It is divided into nine families, with Proterotheriidae and Macraucheniidae being the most diverse and last surviving families. Diversity The body forms of many litopterns, notably in the limb and skull structure, are broadly similar to those of living ungulates, unlike other South American native ungulate groups, which are often strongly divergent from living ungulates. Paleocene and Eocene litopterns generally had small body masses, with '' Protolipterna'' ( Protolipternidae) estimated to have had a body mass of , though the Eocene sparnotheriodontids were considerably larger, with estimated body masses ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meridiungulata
South American native ungulates, commonly abbreviated as SANUs, are extinct ungulate-like mammals that were indigenous to South America from the Paleocene (from at least 63 million years ago) until the end of the Late Pleistocene (~12,000 years ago). They represented a dominant element of South America's Cenozoic terrestrial mammal fauna prior to the arrival of living ungulate groups in South America during the Pliocene and Pleistocene as part of the Great American Interchange. They comprise five major groups conventionally ranked as orders— Astrapotheria, Litopterna, Notoungulata, Pyrotheria, and Xenungulata—as well as the primitive " condylarth" groups Didolodontidae and Kollpaniinae. It has been proposed that some or all of the members of this group form a clade, named Meridiungulata, though the relationships of South American ungulates remain largely unresolved. The two largest groups of South American ungulates, the notoungulates and the litopterns, were the only gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraphyly
Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In contrast, a monophyletic grouping (a clade) includes a common ancestor and ''all'' of its descendants. The terms are commonly used in phylogenetics (a subfield of biology) and in the tree model of historical linguistics. Paraphyletic groups are identified by a combination of synapomorphies and symplesiomorphies. If many subgroups are missing from the named group, it is said to be polyparaphyletic. The term received currency during the debates of the 1960s and 1970s accompanying the rise of cladistics, having been coined by zoologist Willi Hennig to apply to well-known taxa like Reptilia (reptiles), which is paraphyletic with respect to birds. Reptilia contains the last common ancestor of reptiles and all descendants of that ancest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxodonta
Toxodontia. Retrieved April 2013. is a suborder of the Meridiungulata, meridiungulate order Notoungulata. Most of the members of the five included families, including the largest notoungulates, share several dental, auditory and tarsal specializations. The group is named after ''Toxodon'', the first example of the group to be discovered by science. Description Isotemnidae, the oldest and most primitive family of toxodonts, were generally large animals with larger canines than other early notoungulates. The family is probably Paraphyly, paraphyletic or Polyphyly, polyphyletic since only primitive dental features unite the 12 included genera, such as a complete dentition with unreduced canines and no Diastema (dentistry), diastemata in the earliest genera. Likewise, they are only weakly linked to other toxodonts by a few dental features, and their primitive cheek tooth pattern can be basal to all notoungulates except notioprogonians. The oldest of the 12 genera in this family i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panperissodactyla
Panperissodactyla ("all perissodactyls", alternatively spelled Pan-Perissodactyla) is a clade of ungulates containing living order Perissodactyla (odd-toed ungulates) and all extinct ungulates more closely related to Perissodactyla than to Artiodactyla (even-toed ungulates). Groups thought to belong to this clade include Anthracobunia (including the families Anthracobunidae and Cambaytheriidae) known from the Paleogene of the Indian subcontinent, as well as the South American native ungulate groups Litopterna and Notoungulata, both of which went extinct approximately 12,000 years ago. Other South American native ungulate groups also possibly belong to the clade, but their placement is uncertain. The enigmatic aquatic Desmostylia have also been suggested to be related to perissodactyls in some studies, though others recover them as members of afrotherian clade Tethytheria. The Northern Hemisphere "condylarth" group Phenacodontidae has been placed as closely related to perissodac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Equus (genus)
''Equus'' () is a genus of mammals in the perissodactyl family (biology), family Equidae, which includes wild horse, horses, Asinus, asses, and zebras. Within the Equidae, ''Equus'' is the only recognized Extant taxon, extant genus, comprising seven living species. Like Equidae more broadly, ''Equus'' has numerous extinct species known only from fossils. The genus originated in North America and dispersed into the Old World and South America during the Early and Middle Pleistocene. Equinae, Equines are odd-toed ungulates with slender legs, long heads, relatively long necks, manes (erect in most subspecies), and long tails. All species are herbivorous, and mostly grazers, with simpler digestive systems than Ruminantia, ruminants but able to subsist on lower-quality vegetation. While the domestic horse and donkey (along with their feral horse, feral descendants) exist worldwide, wild equine populations are limited to Africa and Asia. Wild equine social systems are in two forms; a H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
