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Mesotherium
''Mesotherium'' ("middle beast") is an extinct genus of mesotheriid, a long-lasting family of superficially rodent-like, burrowing notoungulates from South America. It is one of the youngest notoungulates, spanning the Early-Middle Pleistocene, and is the last known member of Typotheria. It was first named by Étienne Serres in 1857, though initially lacked a type species. Another genus name ''Typotherium'', was put forward by Auguste Bravard, and three species were included: however, the name ''Typotherium'' was not applied to any particular specimens, and is thus invalid. A type species for ''Mesotherium'', ''M. cristatum'', was named in 1867, securing its status as a valid genus. ''M. cristatum'' spanned the Early-Middle Pleistocene. In many regards, ''Mesotherium'' is convergent with rodents, to the point where Serres suggested that it was either a missing link between them and " pachyderms" or close to the ancestry of all mammals. Though fairly small compared to some n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesotheriidae
Mesotheriidae ("Middle Beasts") is an extinct family of notoungulate mammals known from the Oligocene through the Pleistocene of South America. Mesotheriids were small to medium-sized herbivorous mammals adapted for digging. Characteristics Mesotheriids were small to medium-sized notoungulates; larger forms were approximately the size of a sheep. Shockey et al., 2007 Additionally, the family is characterized by specializations of the teeth and skeleton. In the dentition, all mesotheriids have ever-growing incisors with enamel restricted to the anterior surface, a condition termed gliriform, as it also occurs in Glires (rodents and lagomorphs). The cheek teeth (premolars and molars) of mesotheriids are high-crowned ( hypsodont) and in advanced members of the family, the cheek teeth are also ever-growing. Mesotheriid skeletons are heavily built and show features associated with digging in living mammals. In particular, fossorial characteristics of mesotheriids include deeply f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Typotheria
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Pleistocene
The Chibanian, more widely known as the Middle Pleistocene (its previous informal name), is an Age (geology), age in the international geologic timescale or a Stage (stratigraphy), stage in chronostratigraphy, being a division of the Pleistocene Epoch within the ongoing Quaternary Period. The Chibanian name was officially ratified in January 2020. It is currently estimated to span the time between 0.7741 annum, Ma (774,100 years ago) and 0.129 Ma (129,000 years ago), also expressed as 774.1–129 ka. It includes the transition in palaeoanthropology from the Lower Paleolithic, Lower to the Middle Paleolithic over 300 ka. The Chibanian is preceded by the Calabrian (stage), Calabrian and succeeded by the Late Pleistocene. The beginning of the Chibanian is the Brunhes–Matuyama reversal, when the Earth's magnetic field last underwent reversal. Its end roughly coincides with the termination of the Penultimate Glacial Period and the onset of the Last Interglacial period (correspondin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auguste Bravard
(Pierre Joseph) Auguste Bravard (18 June 1803 – 28 March 1861) was a French mining engineer turned palaeontologist. He hunted fossils in the Vaucluse, Allier and his native Puy de Dôme. Biography Bravard emigrated to Argentina in the winter of 1852–53 and was a long-term resident in Buenos Aires. He unearthed and studied mammalian fossils, some of which, like the skull of '' Mesotherium'', were sent back to the Muséum d'histoire naturelle, Paris. Pleistocene mammal fossils purchased from Bravard are also in the Museum of Natural History, South Kensington, London, transferred from the British Museum, which had purchased them from Bravard in 1854. Bravard, who became director of the natural history museum in Paraná, upheld geological theories contrary to those of Charles Darwin. From Buenos Aires, he explored in BahÃa Blanca, resulting in his ''Mapa geológico y topográfico de los alrededores de BahÃa Blanca, Buenos Aires'' (1857). He also explored the Paraná basin an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monograph
A monograph is generally a long-form work on one (usually scholarly) subject, or one aspect of a subject, typically created by a single author or artist (or, sometimes, by two or more authors). Traditionally it is in written form and published as a book, but it may be an artwork, audiovisual work, or exhibition made up of visual artworks. In library cataloguing, the word has a specific and broader meaning, while in the United States, the Food and Drug Administration uses the term to mean a set of published standards. Written works Academic works The English term ''monograph'' is derived from modern Latin , which has its root in Greek. In the English word, ''mono-'' means and ''-graph'' means . Unlike a textbook, which surveys the state of knowledge in a field, the main purpose of a monograph is to present primary research and original scholarship. This research is presented at length, distinguishing a monograph from an article. For these reasons, publication of a monograph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
George Gaylord Simpson
George Gaylord Simpson (June 16, 1902 – October 6, 1984) was an American paleontologist. Simpson was perhaps the most influential paleontologist of the twentieth century, and a major participant in the modern synthesis, contributing '' Tempo and Mode in Evolution'' (1944), ''The Meaning of Evolution'' (1949) and ''The Major Features of Evolution'' (1953). He was an expert on extinct mammals and their intercontinental migrations. Simpson was extraordinarily knowledgeable about Mesozoic fossil mammals and fossil mammals of North and South America. He anticipated such concepts as punctuated equilibrium (in ''Tempo and Mode'') and dispelled the myth that the evolution of the horse was a linear process culminating in the modern '' Equus caballus''. He coined the word '' hypodigm'' in 1940, and published extensively on the taxonomy of fossil and extant mammals. Simpson was influentially, and incorrectly, opposed to Alfred Wegener's theory of continental drift, but accepted the th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Étienne Serres
Antoine Étienne Renaud Augustin Serres (12 September 1786, Clairac – 22 January 1868, Paris) was a French physician and embryologist. He has been considered a pioneer of neurology. He was among the first to formulate the recapitulation theory. Life and work Étienne Serres was the son of physician Jean Jacques Serres, "maître chirurgien" at Clairac and Marie Roussel. He followed a brother who died young in Paris to study medicine in 1803 and received his medical doctorate in 1808, second of eight students who completed their residentship. He defended a thesis titled Essai sur la certitude et l’incertitude en medecine (essay on certainty and uncertainty in medicine) in 1810 which was based on the ideas of Pierre Jean Georges Cabanis (1757–1808). During the Battle of Paris (1814), Battle of Paris he was shot while treating patients. The bullet was not removed and he suffered from osteitis. He afterwards worked at the Hôtel-Dieu de Paris and the Hôpital de la Pitié ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla). The jawbone is the skull's only movable, posable bone, sharing Temporomandibular joint, joints with the cranium's temporal bones. The mandible hosts the lower Human tooth, teeth (their depth delineated by the alveolar process). Many muscles attach to the bone, which also hosts nerves (some connecting to the teeth) and blood vessels. Amongst other functions, the jawbone is essential for chewing food. Owing to the Neolithic Revolution, Neolithic advent of agriculture (), human jaws evolved to be Human jaw shrinkage, smaller. Although it is the strongest bone of the facial skeleton, the mandible tends to deform in old age; it is also subject to Mandibular fracture, fracturing. Surgery allows for the removal of jawbone fragments (or its entirety) as well a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
