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Nannocetus
''Nannocetus'' is an extinct baleen whale belonging to the family Cetotheriidae. Description ''Nannocetus'' is a diminutive mysticete measuring 13 feet (4 meters) long. It is characterized by the ventral orientation (in posterior view) of the postglenoid process; postglenoid process twisted medially (in ventral view) relative to the anteroposterior axis of the skull; equal projection of the ventral and dorsal lobes of the tympanic than the dorsal lobe; deeper notch separating the two lobes of the tympanic; reniform morphology of the tympanic in ventral view; lip of the tympanic slightly inflated; sub-rectilinear medial edge of the involucrum with a step in its anterior third; anterior process of the petrosal sub-triangular; thin crista transversa of the petrosal; and pars cochlearis hemispherical. Taxonomy and classification The holotype is UCMP 26502. It was collected from the Late Miocene ( Messinian) Towsley Formation of Humphreys, Los Angeles County, California Cali ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cetotheriidae
Cetotheriidae is a family of baleen whales (parvorder Mysticeti). The family is known to have existed from the Late Oligocene to the Early Pleistocene before going extinct. Although some phylogenetic studies conducted by recovered the living pygmy right whale as a member of Cetotheriidae, making the pygmy right whale the only living cetotheriid, other authors either dispute this placement or recover Neobalaenidae as a sister group to Cetotheriidae. Taxonomy After its description by Brant in 1872, Cetotheriidae was used as a wastebasket taxon for baleen whales which were not assignable to extant whale families. Comparing the cranial and mandibular morphology of 23 taxa (including late archaeocetes and both fossil and extant mysticetes), found Cetotheriidae in this traditional sense to be polyphyletic. Based on ten cranial characters, they also concluded that of the twelve included fossil baleen-bearing mysticetes, six formed a monophyletic group, Cetotheriidae ''sensu stricto' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baleen Whales
Baleen whales (systematic name Mysticeti), also known as whalebone whales, are a parvorder of carnivorous marine mammals of the infraorder Cetacea (whales, dolphins and porpoises) which use keratinaceous baleen plates (or "whalebone") in their mouths to sieve planktonic creatures from the water. Mysticeti comprises the families Balaenidae (right and bowhead whales), Balaenopteridae (rorquals and 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 mesonychids, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, the Arabian Peninsula collided with Eurasia, severing the connection between the Mediterranean and Indian Ocean, and allowing a faunal interchange to occur between Eurasia and Africa, including the dispersal of proboscideans into Eurasia. During the ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen(s). Article 67.1 A similar concept is used for suprageneric groups and called a type genus. In botanical nomenclature, these terms have no formal standing under the code of nomenclature, but are sometimes borrowed from zoological nomenclature. In botany, the type of a genus name is a specimen (or, rarely, an illustration) which is also the type of a species name. The species name that has that type can also be referred to as the type of the genus name. Names of genus and family ranks, the various subdivisions of those ranks, and some higher-rank names based on genus names, have such types. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messinian
The Messinian is in the geologic timescale the last age or uppermost stage of the Miocene. It spans the time between 7.246 ± 0.005 Ma and 5.333 ± 0.005 Ma (million years ago). It follows the Tortonian and is followed by the Zanclean, the first age of the Pliocene. The Messinian overlaps the Turolian European Land Mammal Mega Zone (more precisely MN 12 and 13) and the Pontian Central European Paratethys Stage. It also overlaps the late Huayquerian and early Montehermosan South American Land Mammal Ages, and falls inside the more extensive Hemphillian North American Land Mammal Age. During the Messinian, around 6 million years ago, the Messinian salinity crisis took place, which brought about repeated desiccations of the Mediterranean Sea. Definition The Messinian was introduced by Swiss stratigrapher Karl Mayer-Eymar in 1867. Its name comes from the Italian city of Messina on Sicily, where the Messinian evaporite deposit is of the same age. The base of the Messinian is at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Los Angeles County
Los Angeles County, officially the County of Los Angeles, and sometimes abbreviated as L.A. County, is the most populous county in the United States and in the U.S. state of California, with 9,861,224 residents estimated as of 2022. It is the most populous non–state-level government entity in the United States. Its population is greater than that of 40 individual U.S. states. At and with 88 incorporated cities and many unincorporated areas, it is home to more than one-quarter of California residents and is one of the most ethnically diverse counties in the United States. Its county seat, Los Angeles, is also California's most populous city and the second-most populous city in the United States, with about 3.9 million residents. In recent times, statewide droughts in California have placed great strain on the County’s (and the City of Los Angeles's) water security. History Los Angeles County is one of the original counties of California, created at the time of stat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
California
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territories of the United States by population, most populous U.S. state and the List of U.S. states and territories by area, 3rd largest by area. It is also the most populated Administrative division, subnational entity in North America and the 34th most populous in the world. The Greater Los Angeles area and the San Francisco Bay Area are the nation's second and fifth most populous Statistical area (United States), urban regions respectively, with the former having more than 18.7million residents and the latter having over 9.6million. Sacramento, California, Sacramento is the state's capital, while Los Angeles is the List of largest California cities by population, most populous city in the state and the List of United States cities by population, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene Cetaceans
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" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, the Arabian Peninsula collided with Eurasia, severing the connection between the Mediterranean and Indian Ocean, and allowing a faunal interchange to occur between Eurasia and Africa, including the dispersal of proboscideans into Eurasia. During the late ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Miocene Mammals Of North America
The Miocene ( ) is the first geological epoch of the Neogene The Neogene ( ), informally Upper Tertiary or Late Tertiary, is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period million years ago ( Mya) to the beginning of the present Quaternary Period Mya. ... 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" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene is preceded by the Oligocene and is followed by the Pliocene. As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages. The Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. During the Early Miocene, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Cetacean Genera
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 1929
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] |
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