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Megadolodus
''Megadolodus'' is an extinct genus of proterotheriid litopterns. History The first fossils of ''Megadolodus'' were uncovered from the Villavieja Formation, in the fossil locality La Venta, in what is today Colombia, in terrains dated from the Middle Miocene, between 13.5 and 11.8 millions of years ago. The genus was described in 1956 after the holotype UCMP 39270, consisting in a left mandible preserving the fourth premolar, the first molar and roots from the second molar, and discovered during an expedition organized by the University of California and directed by Ruben A. Stirton. Those few remains led Malcolm McKenna,Malcolm C. McKenna. Survival of primitive notoungulates and condylarths into the Miocene of Colombia. ''American Journal of Science'', Vol. 254, December 1956, P.736-743 who described them in his 1956 article, to believe they originated from a late surviving Didolodontidae, a family of primitive ungulates that went extinct during the end of the Eocene, 25 mill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laventan
The Laventan () age is a period of geologic time (13.8 to 11.8 Ma) within the Middle Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Colloncuran and precedes the Mayoan age. Etymology The age is named after the Miocene Lagerstätte La Venta, where a rich biodiversity from the Middle Miocene has been recovered from the Honda Group. Formations Fossil content Correlations The Laventan (13.8 to 11.8 Ma) correlates with: * NALMA ** latest Barstovian (15.97-13.65 Ma)Barstovian at .org ** early |
Proterotheriidae
Proterotheriidae is an extinction, extinct family of Litopterna, litoptern ungulates known from the Eocene-Late Pleistocene of South America. Members of the group were small-medium sized cursorial Herbivore, herbivores with brachydont Tooth, teeth, with their Toe, toes showing progressive reduction, with later members of the group bearing weight on a single large toe similar to living Horse, horses. Description Two subfamilies and 18 genera of Proterotheriidae are known. All forms were small or medium-sized. Typical is a reduction of the number of toes and brachydont or mesodont teeth. The family is recorded since the late Palaeocene. Various fossils are known from many parts of the South American continent. The diversity decreased in the Miocene to Pliocene and it has been assumed for a long time that they entirely disappeared in the late Pliocene. However, fossils found in Argentina, Brazil and Uruguay show that one member of the group, ''Neolicaphrium recens'' survived into ... [...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] |
Honda Group, Colombia
The Honda Group (, Tsh, Ngh) is a group (geology), geological group of the Upper Magdalena Basin, Upper and Middle Magdalena Basins and the adjacent Cordillera Central (Colombia), Central and Cordillera Oriental (Colombia), Eastern Ranges of the Colombian Andes. The group, in older literature also defined as formation, is in its present-day type section in the Tatacoa Desert in the departments of Colombia, department of Huila Department, Huila subdivided into two main formations; La Victoria and Villavieja. The group was originally defined in and named after Honda, Tolima, Honda, Tolima, but has been redefined based on the many fossil finds in the Tatacoa Desert, to the south. In the original type section of its occurrence, the thick group is subdivided into three formations, from old to young; Cambrás, San Antonio and Los Limones. The group dates to the Neogene period; in its broadest definition from the Oligocene, Late Oligocene to Miocene, Late Miocene, and in the redefine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bounodus
''Bounodus'' is an extinct genus of ungulates native from South America, belonging to the order Litopterna. Its remains were found in Miocene rocks from the Urumaco Formation of northern Venezuela. The genus is only known from its holotype, AMU-CURS 44, a fragmentary right maxilla preserving teeth from the fourth premolar to the third molar and the alveolus of the third premolar, exhibiting a typical bunodont structure in the animal dentition, a characteristic shared with its close relative '' Megadolodus''. The postcranial skeleton of the genus is unknown. Its dentition indicates that the animal was omnivorous, with teeth adapted to potentially eat shelled fruits, as well as the molluscs and crustaceans that thrived in the wetlands that covered most of North-West South America, including the Urumaco Formation, during the Neogene. The genus name, ''Bounodus'', is composed of the Greek prefix ''Bouno-'', meaning "hill", and the Greek suffix ''-odus'', meaning ''tooth'', in allusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Venta (Colombia)
La Venta is a fossil locality located in the modern departments of Tolima and Huila in Colombia. This site is one of the richest Neogene fossil assemblages in South America and represents the best-known Cenozoic fossil site outside of Argentina. It provides a glimpse of what life in the region was like before the main wave of the Great American Interchange. Geology The fossils occur in Middle Miocene rocks of the Honda Group, which is divided into the younger Villavieja Formation and the older La Victoria Formation. The La Venta fauna contained ancient species of animal genera and families still alive today, as well as some entirely extinct prehistoric lineages. These animals lived some 13.8 to 12 million years ago in the Laventan age, which was named after La Venta. At that time, the climate of the region was wetter than today and there was much forest of trees similar (and probably related) to the ''sapino'' ('' Goupia glabra'') of our time. List of fauna Fossil anima ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tusk
Tusks are elongated, continuously growing front teeth that protrude well beyond the mouth of certain mammal species. They are most commonly canine tooth, canine teeth, as with Narwhal, narwhals, chevrotains, musk deer, water deer, muntjac, pigs, peccary, peccaries, hippopotamuses and walruses, or, in the case of elephants, elongated incisors. Tusks share common features such as extra-oral position, growth pattern, composition and structure, and lack of contribution to ingestion. Tusks are thought to have adapted to the extra-oral environments, like dry or aquatic or arctic. In most tusked species both the males and the females have tusks although the males' are larger. Most mammals with tusks have a pair of them growing out from either side of the mouth. Tusks are generally curved and have a smooth, continuous surface. The male narwhal's straight single Helix, helical tusk, which usually grows out from the left of the mouth, is an exception to the typical features of tusks describ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canine Tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, eye teeth, vampire teeth, or fangs, are the relatively long, pointed teeth. In the context of the upper jaw, they are also known as '' fangs''. They can appear more flattened, however, causing them to resemble incisors and leading them to be called ''incisiform''. They developed and are used primarily for firmly holding food in order to tear it apart, and occasionally as weapons. They are often the largest teeth in a mammal's mouth. Individuals of most species that develop them normally have four, two in the upper jaw and two in the lower, separated within each jaw by incisors; humans and dogs are examples. In most species, canines are the anterior-most teeth in the maxillary bone. The four canines in humans are the two upper maxillary canines and the two lower mandibular canines. They are specially prominent in dogs (Canidae), hence the name. Details There are generally four canine teeth: two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypocone
A cusp is a pointed, projecting, or elevated feature. In animals, it is usually used to refer to raised points on the crowns of teeth. The concept is also used with regard to the leaflets of the four heart valves. The mitral valve, which has two cusps, is also known as the bicuspid valve, and the tricuspid valve has three cusps. In humans A cusp is an occlusal or incisal eminence on a tooth. Canine teeth, otherwise known as cuspids, each possess a single cusp, while premolars, otherwise known as bicuspids, possess two each. Molars normally possess either four or five cusps. In certain populations the maxillary molars, especially first molars, will possess a fifth cusp situated on the mesiolingual cusp known as the Cusp of Carabelli. One other variation of the upper first premolar is the 'Uto-Aztecan' upper premolar. It is a bulge on the buccal cusp that is only found in Native American Indians, with highest frequencies of occurrence in Arizona. The name is not a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diadiaphorus
''Diadiaphorus'' is an extinct genus of litoptern mammal from the Miocene of Argentina ( Ituzaingó, Pinturas, Chiquimil and Santa Cruz Formations) and Bolivia ( Nazareno Formation), South America. Description ''Diadiaphorus'' closely resembled a horse, but was only around in body length with a weight , similar to a modern sheep.D. Patterson, Bruce (2012) ''Bones, Clones, and Biomes: The History and Geography of Recent Neotropical Mammals'' p.92 It had three toes, only one of which touched the ground. This toe had a large hoof; the two outer toes were rudimentary, much like those of early horses such as ''Merychippus''. Unlike horses, however, ''Diadiaphorus'' lacked fused limb bones. Its skull was short and had a relatively large brain cavity. Judging from its low molars The molars or molar teeth are large, flat tooth, teeth at the back of the mouth. They are more developed in mammal, mammals. They are used primarily to comminution, grind food during mastication, chew ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thoatherium
''Thoatherium'' (meaning "active swift-beast") is an extinct genus of litoptern mammals from the Early Miocene of Argentina. Fossils of the genus have been found in the Santa Cruz Formation in Argentina.''Thoatherium'' at .org Description With a length of , the -like ''Thoatherium'' was a small representative of the order . Judging from its long legs, it was a fast runner. ''Thoatherium'' had remarkably reduced toes; ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Horses
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million years from a small multi-toed creature, '' Eohippus'', into the large, single-toed animal of today. Humans began domesticating horses around 4000 BCE in Central Asia, and their domestication is believed to have been widespread by 3000 BCE. Horses in the subspecies ''caballus'' are domesticated, although some domesticated populations live in the wild as feral horses. These feral populations are not true wild horses, which are horses that have never been domesticated. There is an extensive, specialized vocabulary used to describe equine-related concepts, covering everything from anatomy to life stages, size, colors, markings, breeds, locomotion, and behavior. Horses are adapted to run, allowing them to quickly escape predators, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
