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Equus Amerhippus
''Equus neogeus'' is an extinct species of Equinae, equine native to South America during the Pleistocene. It was formerly thought to be several distinct species within the subgenus ''Amerhippus'', but was later shown to be a single morphologically variable species. It is thought to be closely related to true horses. Taxonomy While they have formerly been referred to as belonging to 5 separate species, this has been revised down into three, and more recently a single, morphologically variable species ''Equus neogeus''. Some authors continue to recognise three species, restricting ''Equus neogeus'' to large-sized individuals spanning from the Pampas to Northeast Brazil, while separating the smaller ''Equus andium'' for populations in the northern-central Andes, and ''Equus insulatus'' for medium-sized animals spanning from Bolivia to Venezuela. These authors suggest that ''E. insulatus'' was the ancestor of the other species. Historically, South American ''Equus'' species were pl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek () 'most' and (; Latinized as ) 'new'. The aridification and cooling trends of the preceding Neogene were continued in the Pleistocene. The climate was strongly variable depending on the glacial cycle, oscillating between cold Glacial period, glacial periods and warmer Interglacial, int ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bogotá Savanna
The Bogotá savanna is a savanna#Savanna ecoregions, montane savanna, located in the southwestern part of the Altiplano Cundiboyacense in the center of Colombia. The Bogotá savanna has an extent of and an average altitude of . The savanna is situated in the Cordillera Oriental (Colombia), Eastern Ranges of the Colombian Andes. The Bogotá savanna is crossed from northeast to southwest by the long Bogotá River, which at the southwestern edge of the plateau forms the Tequendama Falls (''Salto del Tequendama''). Other rivers, such as the Subachoque River, Subachoque, Bojacá River, Bojacá, Fucha River, Fucha, Soacha River, Soacha and Tunjuelo Rivers, tributaries of the Bogotá River, form smaller valleys with very fertile soils dedicated to agriculture and cattle-breeding. Before the Spanish conquest of the Muisca, Spanish conquest of the Bogotá savanna, the area was inhabited by the indigenous Muisca people, Muisca, who formed a loose confederation of various ''caciques'', na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fishtail Projectile Point
Fishtail points, also known as Fell points are a style of Paleoindian projectile point widespread across much of South America at the end of the Late Pleistocene, around 13-12,000 years ago. They are thought to have been multifunctional, serving as cutting tools, as well as hafted to spears to use as hunting weapons, possibly in combination with spear throwers. Chronology and origin Their chronological timing is disputed. Some authors favour a short chronology spanning 12,800–12,200 years Before Present (BP), while others favour a long chronology spanning 13,500–10,200 years BP. It is the earliest widespread lithic style in South America, being contemporaneous in its earlier stages to the use of Clovis points in North America. Fishtail points may be derived from Clovis points, or possibly from Fishtail-like points found on the Gulf Coast of North America and in Central America. Description, use and association with other tools The name "Fishtail point" derives from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buenos Aires
Buenos Aires, controlled by the government of the Autonomous City of Buenos Aires, is the Capital city, capital and largest city of Argentina. It is located on the southwest of the Río de la Plata. Buenos Aires is classified as an Alpha− global city, according to the Globalization and World Cities Research Network, GaWC 2024 ranking. The city proper has a population of 3.1 million and its urban area 16.7 million, making it the List of metropolitan areas, twentieth largest metropolitan area in the world. It is known for its preserved eclecticism, eclectic European #Architecture, architecture and rich culture, cultural life. It is a multiculturalism, multicultural city that is home to multiple ethnic and religious groups, contributing to its culture as well as to the dialect spoken in the city and in some other parts of the country. This is because since the 19th century, the city, and the country in general, has been a major recipient of millions of Immigration to Argentina, im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Before Present
Before Present (BP) or "years before present (YBP)" is a time scale used mainly in archaeology, geology, and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because the "present" time changes, standard practice is to use 1January 1950 as the commencement date (epoch) of the age scale, with 1950 being labelled as the "standard year". The abbreviation "BP" has been interpreted retrospectively as "Before Physics", which refers to the time before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, which scientists must account for when using radiocarbon dating for dates of origin that may fall after this year. In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating; the alternative notation "RCYBP" stands for the explicit "radio carbon years before present". Usage The BP scale is s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Pleistocene Extinctions
The Late Pleistocene to the beginning of the Holocene saw the extinction of the majority of the world's megafauna, typically defined as animal species having body masses over , which resulted in a collapse in faunal density and diversity across the globe. The extinctions during the Late Pleistocene are differentiated from previous extinctions by their extreme size bias towards large animals (with small animals being largely unaffected), and widespread absence of ecological succession to replace these extinct megafaunal species, and the regime shift of previously established faunal relationships and habitats as a consequence. The timing and severity of the extinctions varied by region and are generally thought to have been driven by humans, climatic change, or a combination of both. Human impact on megafauna populations is thought to have been driven by hunting ("overkill"), as well as possibly environmental alteration. The relative importance of human vs climatic factors in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prairie
Prairies are ecosystems considered part of the temperate grasslands, savannas, and shrublands biome by ecologists, based on similar temperate climates, moderate rainfall, and a composition of grasses, herbs, and shrubs, rather than trees, as the dominant vegetation type. Temperate grassland regions include the Pampas of Argentina, Brazil and Uruguay, and the steppe of Romania, Ukraine, Russia, and Kazakhstan. Lands typically referred to as "prairie" (a French loan word) tend to be in North America. The term encompasses the lower and mid-latitude of the area referred to as the Interior Plains of Canada, the United States, and Mexico. It includes all of the Great Plains as well as the wetter, hillier land to the east. From west to east, generally the drier expanse of shortgrass prairie gives way to mixed grass prairie and ultimately the richer and wetter soils of the tallgrass prairie. In the U.S., the area is constituted by most or all of the states, from north to south, of North ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C3 Carbon Fixation
carbon fixation is the most common of three metabolic pathways for carbon fixation in photosynthesis, the other two being and CAM. This process converts carbon dioxide and ribulose bisphosphate (RuBP, a 5-carbon sugar) into two molecules of 3-phosphoglycerate through the following reaction: :CO2 + H2O + RuBP → (2) 3-phosphoglycerate This reaction was first discovered by Melvin Calvin, Andrew Benson and James Bassham in 1950. C3 carbon fixation occurs in all plants as the first step of the Calvin–Benson cycle. (In and CAM plants, carbon dioxide is drawn out of malate and into this reaction rather than directly from the air.) Plants that survive solely on fixation ( plants) tend to thrive in areas where sunlight intensity is moderate, temperatures are moderate, carbon dioxide concentrations are around 200 ppm or higher, and groundwater is plentiful. The plants, originating during Mesozoic and Paleozoic eras, predate the plants and still represent approximatel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C4 Carbon Fixation
carbon fixation or the Hatch–Slack pathway is one of three known photosynthetic processes of carbon fixation in plants. It owes the names to the 1960s discovery by Marshall Davidson Hatch and Charles Roger Slack. fixation is an addition to the ancestral and more common carbon fixation. The main carboxylating enzyme in photosynthesis is called RuBisCO, which catalyses two distinct reactions using either (carboxylation) or oxygen (oxygenation) as a substrate. RuBisCO oxygenation gives rise to phosphoglycolate, which is toxic and requires the expenditure of energy to recycle through photorespiration. photosynthesis reduces photorespiration by concentrating around RuBisCO. To enable RuBisCO to work in a cellular environment where there is a lot of carbon dioxide and very little oxygen, leaves generally contain two partially isolated compartments called mesophyll cells and bundle-sheath cells. is initially fixed in the mesophyll cells in a reaction catalysed by th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grazing (behaviour)
Grazing is a method of eating, feeding in which a herbivore feeds on low-growing plants such as grasses or other multicellular organisms, such as algae. Many species of animals can be said to be grazers, from large animals such as Hippopotamus, hippopotamuses to small aquatic Snail, snails. Grazing Ethology, behaviour is a type of List of feeding behaviours, feeding strategy within the ecology of a species. Specific grazing strategies include Graminivore, graminivory (eating grasses); coprophagy (producing part-digested pellets which are reingested); pseudoruminant (having a multi-chambered stomach but not chewing the cud); and grazing on plants other than grass, such as on marine algae. Grazing's ecological effects can include redistributing nutrients, keeping grasslands open or favouring a particular species over another. Ecology Many small selective herbivores follow larger grazers which skim off the highest, tough growth of grasses, exposing tender shoots. For terrestrial a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarija Department
Tarija () is a department in Bolivia. It is located in south-eastern Bolivia bordering with Argentina to the south and Paraguay to the east. According to the 2024 census, it has a population of 534,348 inhabitants. It has an area of . The city of Tarija is the capital of the department. Subdivisions The department is divided into five provinces and one autonomous region: # Gran Chaco Province (autonomous region) # Aniceto Arce Province # José María Avilés Province # Cercado Province # Eustaquio Méndez Province # Burdett O'Connor Province Notable places in Tarija include: * Villamontes in the department's oil-producing eastern scrubland. Villamontes has recorded the hottest temperature ever in Bolivia, , several times, most recently on 29 October 2010. * Bermejo, a border town adjoining Aguas Blancas, Argentina * Yacuiba, a border town with Argentina. The Department of Tarija is renowned for its mild, pleasant climate, and comprises one of the country's foremost ... [...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] |
