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Pachycetinae
Pachycetinae is an extinct subfamily of Basilosauridae, basilosaurid cetaceans that lived during the middle Eocene. The best-dated remains stem from Bartonian strata, but some finds suggest that they could have first appeared during the Lutetian and may have survived until the Priabonian. Fossils of pachycetines are chiefly known from the southern United States, Ukraine, Morocco and Germany, among others. They differ from other basilosaurids in having pachyostotic and osteosclerotic vertebrae and ribs, making them denser and heavier by comparison. Based on this it has been suggested that these whales lived in shallow waters and that these thickened bones act as a buoyancy control as seen in sirenians. Analysis of the teeth suggests that pachycetines had a varying diet, with the robust teeth of the larger ''Pachycetus'' indicating that it possibly fed on sharks, whereas the more gracile teeth of ''Antaecetus'' suggest a diet of smaller prey items. The clade currently only includes t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachycetus
''Pachycetus'' (meaning "thick whale") is an extinct genus of Pachycetinae, pachycetine basilosaurid from Middle Eocene of the eastern United States (North Carolina & Virginia) and Europe (chiefly Germany and Ukraine). The best known remains generally suggest that ''Pachycetus'' lived during the Bartonian, however, fossil finds have also been recovered from sediments of less certain age that could suggest that it may have also lived during the Late Lutetian and Early Priabonian. ''Pachycetus'' is primarily known from vertebrae and ribs and is characterized by its highly osteosclerotic and pachyostotic skeleton. This means the bones not only featured thickened rings of cortical bone surrounding the internal cancellous bone, but the cortical bone was furthermore much denser than in other basilosaurids. Two species of ''Pachycetus'' are recognized: ''Pachycetus paulsonii'' from Europe and ''Pachycetus wardii'' from the United States. A third species might be represented by ''"Zeuglo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antaecetus
''Antaecetus'' is an extinct genus of pachycetine basilosaurid from the middle Eocene Aridal Formation of Morocco as well as the Fayum, Egypt. ''Antaecetus'', although known from fewer remains in total, is markedly more complete than the closely related ''Pachycetus'', with one specimen preserving large parts of the vertebral column up to the lumbar vertebrae and a well preserved skull. Based on these remains ''Antaecetus'' appears to have been smaller than ''Pachycetus'', with a proportionally smaller head and much more gracile teeth. Both genera however share a highly osteosclerotic and pachyostotic skeleton, greatly increasing their weight and possibly serving as additional ballast. In turn the elongation and thickening of the vertebrae severely impacts the animals movement, most likely causing it to have been much slower and far less mobile than other archaeocetes. It has been proposed that ''Antaecetus'' was a slow moving inhabitant of shallow coastal waters, where it would ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supayacetus
''Supayacetus'' is an extinct genus of basilosaurid cetacean from the Middle Eocene (Bartonian stage) Paracas Formation of Peru. It has been noted for its relatively small size and basal morphology, with the sternum bearing close resemblance to those of protocetids. Due to this, it has been traditionally placed as one of the basalmost basilosaurids, except for a 2023 study that places it within the family Pachycetinae close to Neoceti. ''Supayacetus'' is monotypic, meaning the genus includes only a single species: ''S. muizoni''. Discovery and naming ''Supayacetus'' is known from the holotype specimen MUSM 1465, a partial skeleton consisting of assorted remains including a badly weathered skull, various vertebrae and ribs, teeth as well as parts of the forelimbs and the sternum. As ''Ocucajea'', it was collected in the Archaeocete Valley site, located within the middle Eocene () Paracas Formation of the Pisco Basin, Peru. The genus is named after Supay, the Incan god of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basilosauridae
Basilosauridae is a family of extinct cetaceans that lived during the middle to late Eocene. Basilosaurids are known from all continents including Antarctica, and are probably the first fully aquatic cetaceans.Buono M, Fordyce R.E., Marx F.G., Fernández M.S. & Reguero M. (2019). "Eocene Antarctica: a window into the earliest history of modern whales". ''Advances in Polar Science'' 30(3): p. 293-302. doi:10.13679/j.advps.2019.0005 The group is noted to be a paraphyletic assemblage of stem group whales from which the monophyletic Neoceti are derived. Characteristics Basilosaurids ranged in size from and were fairly similar to modern cetaceans in overall body form and function. Some genera tend to show signs of convergent evolution with mosasaurs by having long serpentine body shape, which suggests that this body plan seems to have been rather successful. Basilosaurid forelimbs have broad and fan-shaped scapulae attached to a humerus, radius, and ulna which are flattened i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lutetian
The Lutetian is, in the geologic timescale, a stage (stratigraphy), stage or age (geology), age in the Eocene. It spans the time between . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it is sometimes referred to as the Middle Eocene Subepoch. Stratigraphic definition The Lutetian was named after Lutetia, the Latin language, Latin name for the city of Paris. The Lutetian Stage was introduced in scientific literature by French geologist Albert de Lapparent in 1883 and revised by A. Blondeau in 1981. The base of the Lutetian Stage is at the first appearance of the nanofossil ''Blackites inflatus'', according to an official reference profile (GSSP) established in 2011. Of two candidates located in Spain, the Gorrondatxe section was chosen.See thwebsite of Eustoquio Molinafor these candidates. The top of the Lutetian (the base of the Bartonian) is at the first appearance of calcareous nannofossils, calcareous nanoplankton s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remington Kellogg
Arthur Remington Kellogg (5 October 1892 – 8 May 1969) was an American naturalist and a director of the United States National Museum. His work focused on marine mammals. Early life and career Kellogg was born in Davenport, Iowa, and quickly dropped the name "Arthur". From a young age he devoted his free time to the study of wildlife. He built up his own small collection of mounted birds and mammals and by the time he came to choose a university he had determined he would become a naturalist. Choosing the University of Kansas as it offered courses in his chosen field, he first studied entomology, later switching to the study of mammals. From 1913 to 1916 he worked under Charles D. Bunker, the curator of birds and mammals at the university's Museum of Natural History. He published his first paper as a result of his work with Bunker. Kellogg graduated in 1915 and received his M.A. the following year. After graduating, he immediately began work with the United States Bureau of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pierre-Joseph Van Beneden
Pierre-Joseph Van Beneden FRS FRSE FGS FZS (19 December 1809 – 8 January 1894) was a Belgian zoologist and paleontologist. He has been credited with introducing the terms " mutualism" and "commensalism" into biology in 1875 and 1876 respectively. Life Born in Mechelen, First French Empire, he studied medicine at the State University of Leuven and studied zoology in Paris under Georges Cuvier (1769–1832). In 1831, he became curator at the natural history museum in Leuven, and from 1836 until 1894, was a professor of zoology at the Catholic University of Leuven. In 1842, he became a member of the ''Académie des sciences de Belgique'', becoming its President in 1881. In 1875, he became a foreign member of the Royal Society of London, and in 1884, an Honorary Fellow of the Royal Society of Edinburgh. In 1843, he established one of the world's first marine laboratories and aquariums. He was the father of biologist Edouard van Beneden (1846–1910). Pierre-Joseph van Beneden died ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mysticete
Baleen whales (), also known as whalebone whales, are marine mammals of the parvorder Mysticeti in the infraorder Cetacea (whales, dolphins and porpoises), which use baleen plates (or "whalebone") in their mouths to sieve plankton from the water. Mysticeti comprises the families Balaenidae (right and bowhead whales), Balaenopteridae (rorquals), Eschrichtiidae (the gray whale) and Cetotheriidae (the pygmy right whale). There are currently 16 species of baleen whales. While cetaceans were historically thought to have descended from mesonychians, molecular evidence instead supports them as a clade of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago. Baleen whales range in size from the and pygmy right whale to the and blue whale, the largest known animal to have ever existed. They are sexually dimorphic. Baleen whales can have streamlined or large bodies, depending on the feeding behavior, and two limbs that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oskar Kuhn
Oskar Kuhn (7 March 1908, Munich – 1 May 1990) was a German palaeontologist. Life and career Kuhn was educated in Dinkelsbühl and Bamberg and then studied natural science, specialising in geology and paleontology, at the University of Munich, from which he received his D. Phil. in 1932. He worked in the University of Munich Geological Institute, among other things on the ''Fossilium Catalogus'' (Catalogue of Fossils), and then in 1938 on a stipend from the Deutsche Forschungsgemeinschaft, moved to the University of Halle, where he worked on the Geiseltal fossils. In 1939 he achieved his Habilitation with a thesis on the Halberstadt Keuper fauna, and in 1940 was named Privatdozent in geology and paleontology. Informed by his Catholic religion, Kuhn was an exponent of idealistic morphology: he viewed evolution as operating only within predetermined morphological classes. In 1943 he declared, "The theory of descent has collapsed." After a political conflict with his mentor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protocetid
Protocetidae, the protocetids, form a paraphyletic, diverse and heterogeneous group of extinct cetaceans known from Asia, Europe, Africa, South America, and North America. Description There were many genera, and some of these are very well known (e.g., ''Rodhocetus''). Known protocetids had large fore- and hindlimbs that could support the body on land, and it is likely that they lived amphibiously: in the sea and on land. It is unclear at present whether protocetids had flukes (the horizontal tail fin of modern cetaceans). However, what is clear is that they are adapted even further to an aquatic life-style. In ''Rodhocetus'', for example, the sacrum – a bone that in land-mammals is a fusion of five vertebrae that connects the pelvis with the rest of the vertebral column – was divided into loose vertebrae. However, the pelvis retain a sacroiliac joint. Furthermore, the nasal openings are now halfway up the snout; a first step towards the telescoped condition in mod ... [...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] |
