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Pascualihippus
''Pascualihippus'' is an extinct genus of notoungulate belonging to the family Notohippidae. It lived during the Late Oligocene, in what is now Bolivia. Description This genus is primarily known from a skull and a few postcranial bones, and it likely was about the size of a sheep. ''Pascualihippus'' had a high skull, with a broad, blunt muzzle, with the two first incisors forming a transverse line across the anterior part of the premaxilla, followed by a narrowing of the muzzle when viewed from above. These characteristics are somewhat similar to those found in Toxodontidae, such as ''Adinotherium'' and '' Nesodon''. However, its incisors had roots and the cheek teeth were quite different from those of "true" toxodonts. The molars of ''Pascualihippus'' lacked the typical bifurcation on the central loop. The premaxillary dental arch was linear, indicating that it likely was a grass bruiser. Unlike its relative '' Eomorphippus'', its incisors were not protruding. Classification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notoungulata
Notoungulata is an extinct order of mammalian ungulates that inhabited South America from the early Paleocene to the Holocene, 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 during the Late Neogene, with only the large toxodontids persisting until the end of the Pleistocene. Collagen analysis suggests that notoungulates are closely related to litopterns, another group of South American ungulates, and their closest living relatives being perissodactyls (odd-toed ungulates), including rhinoceroses, tapirs and equines. but their relationships to other South American ungulates are uncert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Notohippidae
Notohippidae is a paraphyletic extinct family of notoungulate mammals from South America. Notohippids are known from the Eocene and Oligocene epochs.McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level.'' Columbia University Press, New York, 631 pp. Description Although the name notohippids means "southern horses," these animals did not look like horses. The name refers to the teeth very similar to those of horses, with sharp incisors and high-crowned molars suitable for shredding grass. The shape of the skull and particularly the dentition is the result of convergent evolution with the equids, perissodactyl mammals that developed on the northern continents. The body of notohippids was rather stocky, supported by relatively elongated legs equipped with claws (and not hooves). The earliest forms of notohippids possessed low-crowned molars, but in the course of evolution the teeth gradually became more prismatic, and covered with a th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ... Epoch. The Oligocene is the third and final epoch of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salla Formation
Salla (''Kuolajärvi'' until 1936) ( smn, Kyelijävri) is a municipality of Finland, located in Lapland. The municipality has a population of () and covers an area of of which is water. The population density is . The nearby settlement of Sallatunturi is home to the Salla Ski Resort. History Salla is in the Eastern Lapland and as a border area was affected by the Second World War. Red Army troops invaded Finland at Salla during the Winter War but were stopped by the Finnish Army (see Battle of Salla). Parts of the municipality were ceded to the Soviet Union after the war. The ceded part is sometimes called "Old Salla" or ''Vanha Salla''. During the Continuation War the old town of Salla was on the Soviet side of the border. The German XXXVI Corps attacked the Soviet positions in an operation code-named '' Polarfuchs''. With the help of the Finnish 6th Division it managed to occupy all of the ceded territories. At the end of the war the German troops were pushed out of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossils Of Bolivia
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the absolute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleogene Bolivia
The Paleogene ( ; also spelled Palaeogene or Palæogene; informally Lower Tertiary or Early Tertiary) is a geologic period and system that spans 43 million years from the end of the Cretaceous Period million years ago (Mya) to the beginning of the Neogene Period Mya. It is the beginning of the Cenozoic Era of the present Phanerozoic Eon. The earlier term Tertiary Period was used to define the span of time now covered by the Paleogene Period and subsequent Neogene Period; despite no longer being recognised as a formal stratigraphic term, 'Tertiary' is still widely found in earth science literature and remains in informal use. Paleogene is often abbreviated "Pg" (but the United States Geological Survey uses the abbreviation PE for the Paleogene on the Survey's geologic maps). During the Paleogene, mammals diversified from relatively small, simple forms into a large group of diverse animals in the wake of the Cretaceous–Paleogene extinction event that ended the precedi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene Mammals Of South America
The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from the Ancient Greek (''olígos'', "few") and (''kainós'', "new"), and refers to the sparsity of extant forms of molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major changes during the Oligocene included a global expansion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toxodonts
Toxodontia. Retrieved April 2013. is a suborder of the 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 paraphyletic or polyphyletic since only primitive dental features unite the 12 included genera, such as a complete dentition with unreduced canines and no 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 is '' Isotemnus'' known from the Riochican- Casamayoran, b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Argyrohippus
''Argyrohippus'' is an extinct genus of notoungulate, belonging to the family Notohippidae. It lived from the Late Oligocene to the Early Miocene, and its fossilized remains were found in South America. Description This animal was probably vaguely similar in build and size to a goat. It is mostly known from remains of its dentition, which was very specialized : the dentition was complete and continuous (without diastema), but the premolars and molars were hypsodonts. The canines were small. The premolars had a very developed cingulum, while the molars were quite elongated. The shape of the premolars and molar was very reminiscent of those of Equidae. Its most peculiar distinctive characteristics were the cup-shaped internal cingula and the lack of singula on the premolars, and a thick layer of cementum. Classification The genus ''Argyrohippus'' (whose name means "Argentine horse") was first described in 1902 by Florentino Ameghino, based on fossil remains found in Early Mioc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nesodon
''Nesodon'' ("island tooth") Palmer (1904) p. 457. is a genus of Miocene mammal belonging to the extinct order Notoungulata which inhabited southern South America during the Late Oligocene to Miocene living from 29.0 to 16.3 Ma and existed for approximately . It had a relatively large size, weighing up to 554 kg (1221 lbs) and reaching 1.5 m in height.D.Patterson, Bruce (2012) ''Bones, Clones, and Biomes: The History and Geography of Recent Neotropical Mammals'' p.92 Taxonomy ''Nesodon'' was named by Owen (1846). It was assigned to Toxodontidae by Carroll (1988). It was an early member of the family Toxodontidae, which included the well-known Pleistocene genus ''Toxodon''. Like almost all toxodontids, ''Nesodon'' was endemic to South America. In particular, fossils of ''Nesodon'' are known from late early Miocene (Santacrucian SALMA) deposits of Argentina and Chile.Croft et al. (2004), p. 5. Three species of ''Nesodon'' are recognized including a larger spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eomorphippus
''Eomorphippus'' is an extinct genus of notohippid notoungulate that lived from the Late Eocene to the Early Oligocene in what is today South America. Description This animal was approximately the size of a goat, with a build probably more robust. It had a heavy and sturdy skull, with a relatively short muzzle. The dentition was characterized by high-crowned (hypsodont) incisors, posterior premolars and molars. The teeth didn't have cementum. The upper incisors were slightly protruding forward. The third upper incisor was wider than the other two, while the fourth premolar was more molariform than the other premolars, but devoid of a distinct hypocone. The upper molars had hypocones, with a variable but generally deep fissure separating them from the protocones. The fissure was blocked by the medial projection of a hooked structure. Apart from the permanent major fossa, the other fossae are erased with wear. Classification The genus ''Eomorphippus'' was first described in 1901 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can reproduction, produce Fertility, fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
