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Teleoceras Fossiger
''Teleoceras'' (Greek: "perfect" (teleos), "horn" (keratos)) is an extinct genus of rhinocerotid. It lived in North America during the Miocene and Pliocene epochs during the Hemingfordian to the end of Hemphillian from around 17.5 to 4.9 million years ago. It grew up to lengths of long. ''Teleoceras'' went extinct in North America alongside '' Aphelops'' at the end of the Hemphillian, most likely due to rapid climate cooling, increased seasonality and expansion of C4 grasses, as isotopic evidence suggests that the uptake of C4 plants was far less than that in contemporary horses. The Gray Fossil Site in northeast Tennessee, dated to 4.5-5 million years ago, hosts one of the latest-known populations of ''Teleoceras,'' ''Teleoceras aepysoma.'' Description ''Teleoceras'' had much shorter legs than modern rhinos, and a barrel chest, making its build more like that of a hippopotamus than a modern rhino. Based on this description, Henry Fairfield Osborn suggested in 1898 that it w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barstovian
The Barstovian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 16,300,000 to 13,600,000 years BP, a period of . It is usually considered to overlap the Langhian and Serravallian stages of the Middle Miocene. The Barstovian is preceded by the Hemingfordian and followed by the Clarendonian NALMA stages. The Barstovian can be further divided into the substages of: * late Late Barstovian: Lower boundary source of the base of the Langhian (approximate) * early Late Barstovian: Base of the Langhian (approximate) * early/lower Barstovian: Upper boundary source: base of Clarendonian (approximate) Correlations The Barstovian (15.97 to 13.6 Ma) correlates with: * SALMA ** Colloncuran (15.5-13.8 Ma) [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barbourofelis
''Barbourofelis'' is an extinct genus of large, predatory, from a subfamily of feliformia, feliform carnivoran mammals of known as Barbourofelidae, Barbourofelinae, part of the Nimravidae superfamily. ''Barbourofelis'', along with ''Albanosmilus'', was the last members barbourofelids, as well as the last nimravids. ''Barbourofelis'' lived North America and Eurasia during the Miocene epoch from 12 to 7 Annum, Ma. Four species are currently recognized within the genus: ''B. fricki'', ''B. loveorum'', ''B. morrisi'', and ''B. piveteaui''. ''B. loveorum'' directly evolved from from ''B. morrisi'', and later evolved into ''B. fricki''. ''B. morrisi'' likely evolved from ''Albanosmilus'' migrating into North America. With ''B. piveteaui'' evolving from reverse migration from North America into Eurasia. ''B. morrisi'' and ''B. piveteaui'' were the smallest species being about as large as a leopard. ''B. loveorum'' was the second largest species and could’ve weighed anywhere from . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nebraska
Nebraska ( ) is a landlocked U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwest; and Wyoming to the west. Nebraska is the List of U.S. states and territories by area, 16th-largest state by land area, with just over . With a population of over 2 million as of 2024, it is the List of U.S. states and territories by population, 38th-most populous state and the List of states and territories of the United States by population density, eighth-least densely populated. Its List of capitals in the United States, capital is Lincoln, Nebraska, Lincoln, and its List of municipalities in Nebraska, most populous city is Omaha, Nebraska, Omaha, which is on the Missouri River. Nebraska was admitted into the United States in 1867, two years after the end of the American Civil War. The Nebras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ashfall Fossil Beds
The Ashfall Fossil Beds of Antelope County in northeastern Nebraska are rare fossil sites of the type called lagerstätten that, due to extraordinary local conditions, capture an ecological "snapshot" in time of a range of well-preserved fossilized organisms. Ash from a Yellowstone hotspot eruption 10-12 million years ago created these fossilized bone beds. The ash depth was up to 1 foot. The site is protected as Ashfall Fossil Beds State Historical Park, a park that includes a visitor center with interpretive displays and working fossil preparation laboratory, and a protected ongoing excavation site, the Hubbard Rhino Barn, featuring fossil '' Teleoceras'' (native hippo-like ancestral rhinoceros) and ancestral horses. The Ashfall Fossil Beds are especially famous for fossils of mammals from the middle Miocene geologic epoch. The Ashfall Fossil Beds are stratigraphically part of the Serravallian-age Ogallala Group, within the Ash Hollow Formation. Bruneau-Jarbidge event ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Bimaturism
Sexual bimaturism describes a difference in developmental timing between males and females of the same species. Sexual bimaturism can result in sexual dimorphism, but sexual dimorphism could also develop through differential rates of development. In many insects, the larval period of females is longer than that of males, and as a result of this extended growth period, these female insects are larger than their male conspecifics. Male simian primates are generally larger than females of the same species due in part to extended growth periods. Gorillas demonstrate a particularly high degree of sexual bimaturism. Bimaturism can refer to developmental differences within a sex related to secondary sex characteristics. For example, male orangutans reach sexual maturity around age 15 but undergo an additional period of development later in life before they exhibit cheek flanges. Flanged males are generally preferred by females so that unflanged males need different mating strategies to c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeogeography, Palaeoclimatology, Palaeoecology
''Palaeogeography, Palaeoclimatology, Palaeoecology'' ("''Palaeo3''") is a peer-reviewed scientific journal publishing multidisciplinary studies and comprehensive reviews in the field of palaeoenvironmental geology. The journal is edited by Howard Falcon-Lang, Shuzhong Shen, Alex Dickson, Mary Elliot, Meixun Zhao, Lucia Angiolini. It was established in 1965 and is currently published by Elsevier. Indexing and abstracting ''Palaeogeography, Palaeoclimatology, Palaeoecology'' is indexed and abstracted in the following databases: According to the ''Journal Citation Reports'', ''Advance in Space Research'' has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a type of journal ranking. Journals with higher impact factor values are considered more prestigious or important within their field. The Impact Factor of a journa ... of 3.318. References External links * Elsevier academic journals English-language journals Ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Δ18O
In geochemistry, paleoclimatology and paleoceanography ''δ''18O or delta-O-18 is a measure of the deviation in ratio of stable isotopes oxygen-18 (18O) and oxygen-16 (16O). It is commonly used as a measure of the temperature of precipitation, as a measure of groundwater/mineral interactions, and as an indicator of processes that show isotopic fractionation, like methanogenesis. In paleosciences, 18O:16O data from corals, foraminifera and ice cores are used as a proxy for temperature. It is defined as the deviation in "per mil" (‰, parts per thousand) between a sample and a standard: :\delta \ce = \left( \frac - 1 \right) \times 1000 ‰ where the standard has a known isotopic composition, such as Vienna Standard Mean Ocean Water (VSMOW). The fractionation can arise from kinetic, equilibrium, or mass-independent fractionation. Mechanism Foraminifera shells are composed of calcium carbonate (CaCO3) and are found in many common geological environments. The rat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Browsing (herbivory)
Browsing is a type of herbivory in which a herbivore (or, more narrowly defined, a folivore) feeds on leaves, soft Shoot (botany), shoots, or fruits of high-growing, generally woody plants such as shrubs. This is contrasted with Grazing (behaviour), grazing, usually associated with animals feeding on grass or other lower vegetations. Alternatively, grazers are animals eating mainly grass, and browsers are animals eating mainly non-grasses, which include both woody and herbaceous Dicotyledon, dicots. In either case, an example of this dichotomy are goats (which are primarily browsers) and Domestic sheep, sheep (which are primarily grazers). Browse The plant material eaten is known as ''browse'' and is in nature taken directly from the plant, though owners of livestock such as goats and deer may cut twigs or branches for feeding to their stock. In temperate regions, owners take browse before leaf fall, then dry and store it as a winter feed supplement. In time of drought, herdsme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesowear
Mesowear is a method, used in different branches and fields of biology. This method can apply to both extant and extinct animals, according to the scope of the study. Mesowear is based on studying an animal's tooth wearing fingerprint. In brief, each animal has special feeding habits, which cause unique tooth wearing. Rough feeds cause serious tooth abrasion, while smooth one triggers moderate abrasion, so browsers have teeth with moderate abrasion and grazers have teeth with rough abrasion. Scoring systems can quantify tooth abrasion observations and ease comparisons between individuals. Mesowear definition The mesowear method or tooth wear scoring method is a quick and inexpensive process of determining the lifelong diet of a taxon ( grazer or browser) and was first introduced in the year 2000. The mesowear technique can be extended to extinct and also extant animals. Mesowear analyses require large sample populations (>20), which can be problematic for some localities, but the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Microwear
Dental microwear analysis is a method to infer diet and behavior in extinct animals, especially in fossil specimens. It has been used on a variety of taxa, including hominids, victoriapithecids, amphicyonids, canids, ursids, hyaenids, hyaenodontids, equids, rhinocerotids, moschids, tragulids, diprotodontids, varanids, and elasmobranchs. Typically, the patterns of pits and scratches on the occlusal or buccal surface of the enamel are compared with patterns observed in extant species to infer ecological information. Hard foods in particular can lead to distinctive patterns (although see below). Microwear can also be used for inferring behavior, especially those related to the non-masticatory use of teeth as 'tools'. Other uses include investigating weaning in past populations. Methods used to collect data initially involved a microscope and manually collecting information on individual microwear features, but software to automatically collect data have improved markedly in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypsodont
Hypsodont is a pattern of dentition characterized by with high crowns, providing extra material for wear and tear. Some examples of animals with hypsodont dentition are cows and horses; all animals that feed on gritty, fibrous material. The opposite condition is called brachydont. Evolution Since the morphology of the hypsodont tooth is suited to a more abrasive diet, hypsodonty was thought to have evolved concurrently with the spread of grasslands. Grass contains phytoliths, silica-rich granules, which wear away dental tissue more quickly. Analysis has shown, however, that the development of this morphology is out of sync with the spread and flourishing of grasslands. Instead, the ingestion of grit and soil is hypothesized to be the primary driver of hypsodonty, a hypothesis termed the grit, not grass hypothesis. Morphology Hypsodont dentition is characterized by: * high-crowned teeth * A rough, flattish occlusal surface adapted for crushing and grinding * Cementum both ab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henry Fairfield Osborn
Henry Fairfield Osborn, Sr. (August 8, 1857 – November 6, 1935) was an American paleontologist, geologist and eugenics advocate. He was professor of anatomy at Columbia University, president of the American Museum of Natural History for 25 years and a cofounder of the American Eugenics Society. Among his significant contributions include naming the dinosaurs ''Tyrannosaurus'' and ''Velociraptor'', his widely used system of names for dental cusps of mammalian teeth, as well as his research on fossil proboscideans (elephants and their extinct relatives). Osborn was one of the most well known scientists in the United States during his own lifetime, “second only to Albert Einstein", and was a prominent public advocate for the existence of evolution. Active during the eclipse of Darwinism, Osborn was a prominent opponent of natural selection as a mechanism of evolution, favouring the now discredited orthogenesis theory of which he was one of the most prominent advocates. In a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
