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Gomphotherium Land Bridge
The ''Gomphotherium land bridge'' was a land bridge that connected Eurasia to Afro-Arabia between approximately 19 Mya (million years ago) and 15 Mya. Significance Passage of fauna between Eurasia and the Arabian Plate and thus Africa was largely hindered before the Early Miocene, as animals could not cross the open Tethyan seaway. However, during the mid-Burdigalian, the tectonic plates of Afro-Arabia and Eurasia collided, creating a terrestrial isthmus connecting the two landmasses. This faunal exchange that resulted is known as the Proboscidean Datum Event. The land bridge allowed the elephantine gomphotheres and other proboscideans to migrate out of Africa and into Eurasia. It is believed that the connection between the Mediterranean and Indian oceans was temporarily re-established during the Langhian The Langhian is, in the ICS geologic timescale, an age or stage in the middle Miocene Epoch/Series. It spans the time between 15.97 ± 0.05 Ma and 13.65 ± 0.05 Ma (million ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gomphotherium
''Gomphotherium'' (; "nail beast" for its double set of straight tusks) is an extinct genus of gomphothere proboscidean from the Neogene of Eurasia, Africa and North America. It is the most diverse genus of gompothere, with over a dozen valid species. The genus is probably paraphyletic. Description Most species of ''Gomphotherium'' were similar in size to the Asian elephant, with ''G. productum'' (known from a 35-year-old male) measuring tall and weighing . The largest species ''G. steinheimense'', known from a complete 37-year-old male found in Mühldorf, Germany, measured up to tall and weighed . ''Gomphotherium'', like most basal Elephantimorpha, elephantimorphs, had an elongated lower jaw which bore tusks. Species of ''Gomphotherium'' are defined by their conservative molar morphology, which includes "trilophed intermediate molars, third molars with three to four loph(id)s, and pretrite half-loph(id)s typically with anterior and posterior accessory conules that form ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Land Bridge
In biogeography, a land bridge is an isthmus or wider land connection between otherwise separate areas, over which animals and plants are able to cross and colonize new lands. A land bridge can be created by marine regression, in which sea levels fall, exposing shallow, previously submerged sections of continental shelf; or when new land is created by plate tectonics; or occasionally when the sea floor rises due to post-glacial rebound after an ice age. Prominent examples Former land bridges * The Bassian Plain, which linked Australia to Tasmania * The Antarctic Land Bridge, which connected South America, Antarctica, and Australia during the Late Cretaceous and Early Paleogene * The Bering Land Bridge (aka Beringia), which intermittently connected Alaska (Northern America) with Siberia (North Asia) as sea levels rose and fell under the effect of ice ages * GAARlandia, a hypothesized land bridge which potentially connected the Greater Antilles with South America d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurasia
Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents dates back to classical antiquity, antiquity, but their borders have historically been subject to change. For example, the ancient Greeks originally included Africa in Asia but classified Europe as separate land. Eurasia is connected to Africa at the Suez Canal, and the two are sometimes combined to describe the largest contiguous landmass on Earth, Afro-Eurasia. History Eurasia has been the host of many ancient civilizations, including those based in Mesopotamia, Egypt, the Indus Valley and China. In the Axial Age (mid-first millennium BCE), a continuous belt of civilizations stretched through the Eurasian Subtropics, subtropical zone from the Atlantic to the Pacific. This belt became the mainstream of world history for two millennia. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Miocene
The Early Miocene (also known as Lower Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages: the Aquitanian age, Aquitanian and Burdigalian stages. The sub-epoch lasted from 23.03 ± 0.05 annum, Ma to 15.97 ± 0.05 Ma (million years ago). It was preceded by the Oligocene epoch. As the climate started to get cooler, the landscape started to change. New mammals evolved to replace the extinct animals of the Oligocene epoch. The first members of the hyena and weasel family started to evolve to replace the extinct ''Hyaenodon'', entelodonts and bear-dogs. The chalicotheres survived the Oligocene epoch. A new genus of entelodont called ''Daeodon'' evolved in order to adapt to the new habitats and hunt the new prey animals of the Early Miocene epoch; it quickly became the top predator of North America. But it became extinct due to competition from ''Amphicyon'', a newcomer from Eurasia. ''Amphicyon'' bested ''Daeodon'' because the bear-dog's la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethyan Seaway
The Tethys Ocean ( ; ), also called the Tethys Sea or the Neo-Tethys, was a prehistoric ocean during much of the Mesozoic Era and early-mid Cenozoic Era. It was the predecessor to the modern Indian Ocean, the Mediterranean Sea, and the Eurasian inland marine basins (primarily represented today by the Black Sea and Caspian Sea). During the early Mesozoic, as Pangaea broke up, the Tethys Ocean was defined as the ocean located between the ancient continents of Gondwana and Laurasia. After the opening of the Indian and Atlantic oceans during the Cretaceous Period and the breakup of these continents over the same period, it came to be defined as the ocean bordered by the continents of Africa, Eurasia, India, and Australasia. During the early-mid Cenozoic, the Indian, African, Australian and Arabian plates moved north and collided with the Eurasian plate, which created new borders to the ocean, a land barrier to the flow of currents between the Indian and Mediterranean basins, and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burdigalian
The Burdigalian is, in the geologic timescale, an age (geology), age or stage (stratigraphy), stage in the early Miocene. It spans the time between 20.43 ± 0.05 annum, Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian (stage), Aquitanian, the Burdigalian was the first and longest warming period of the MioceneEdward Petuch, Ph.D. Florida Atlantic University, Department of Geosciences. and is succeeded by the Langhian. Stratigraphic definition The name Burdigalian comes from ''Burdigala'', the Latin name for the city of Bordeaux, France. The Burdigalian Stage was introduced in scientific literature by Charles Depéret in 1892. The base of the Burdigalian is at the first appearance of foram species ''Globigerinoides altiaperturus'' and the top of magnetic chronozone C6An. , an official GSSP for the Burdigalian had not yet been assigned. The top of the Burdigalian (the base of the Langhian) is defined by the first appearance of foram species ''Praeorbulina gl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tectonic Plate
Plate tectonics (, ) is the scientific theory that the Earth's lithosphere comprises a number of large tectonic plates, which have been slowly moving since 3–4 billion years ago. The model builds on the concept of , an idea developed during the first decades of the 20th century. Plate tectonics came to be accepted by geoscientists after seafloor spreading was validated in the mid-to-late 1960s. The processes that result in plates and shape Earth's crust are called ''tectonics''. Tectonic plates also occur in other planets and moons. Earth's lithosphere, the rigid outer shell of the planet including the crust and upper mantle, is fractured into seven or eight major plates (depending on how they are defined) and many minor plates or "platelets". Where the plates meet, their relative motion determines the type of plate boundary (or fault): , , or . The relative movement of the plates typically ranges from zero to 10 cm annually. Faults tend to be geologically active, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isthmus
An isthmus (; : isthmuses or isthmi) is a narrow piece of land connecting two larger areas across an expanse of water by which they are otherwise separated. A tombolo is an isthmus that consists of a spit or bar, and a strait is the sea counterpart of an isthmus, a narrow stretch of sea between two landmasses that connects two larger bodies of water. Isthmus vs land bridge vs peninsula ''Isthmus'' and ''land bridge'' are related terms, with isthmus having a broader meaning. A land bridge is an isthmus connecting Earth's major land masses. The term ''land bridge'' is usually used in biogeology to describe land connections that used to exist between continents at various times and were important for the migration of people and various species of animals and plants, e.g. Beringia and Doggerland. An isthmus is a land connection between two bigger landmasses, while a peninsula is rather a land protrusion that is connected to a bigger landmass on one side only and surrounded by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gomphothere
Gomphotheres are an extinct group of proboscideans related to modern elephants. First appearing in Africa during the Oligocene, they dispersed into Eurasia and North America during the Miocene and arrived in South America during the Pleistocene as part of the Great American Interchange. Gomphotheres are a paraphyletic group ancestral to Elephantidae, which contains modern elephants, as well as Stegodontidae. While most famous forms such as '' Gomphotherium'' had long lower jaws with tusks, the ancestral condition for the group, some later members developed shortened (brevirostrine) lower jaws with either vestigial or no lower tusks and outlasted the long-jawed gomphotheres. This change made them look very similar to modern elephants, an example of parallel evolution. During the Pliocene and Early Pleistocene, the diversity of gomphotheres declined, ultimately becoming extinct outside of the Americas. The last two genera, '' Cuvieronius'' ranging southern North America to weste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proboscideans
Proboscidea (; , ) is a taxonomic order of afrotherian mammals containing one living family (Elephantidae) and several extinct families. First described by J. Illiger in 1811, it encompasses the elephants and their close relatives. Three living species of elephant are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. Extinct members of Proboscidea include the deinotheres, mastodons, gomphotheres and stegodonts. The family Elephantidae also contains several extinct groups, including mammoths and ''Palaeoloxodon''. Proboscideans include some of the largest known land mammals, with the elephant '' Palaeoloxodon namadicus'' and mastodon ''"Mammut" borsoni'' suggested to have body masses surpassing , rivalling or exceeding paraceratheres (the otherwise largest known land mammals) in size. The largest extant proboscidean is the African bush elephant, with a world record of size of at the shoulder and . In addition to their enor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Langhian
The Langhian is, in the ICS geologic timescale, an age or stage in the middle Miocene Epoch/Series. It spans the time between 15.97 ± 0.05 Ma and 13.65 ± 0.05 Ma (million years ago) during the Middle Miocene.GeoWhen (2007) The Langhian was a continuing warming period defined by Lorenzo Pareto in 1865, it was originally established in the Langhe area north of Ceva in northern Italy, hence the name. The Langhian is preceded by the Burdigalian and followed by the Serravallian Stage. Stratigraphic definition The base of the Langhian is defined by the first appearance of foraminifer species ''Praeorbulina glomerosa'' and is also coeval with the top of magnetic chronozone C5Cn.1n. A GSSP for the Langhian Stage was not yet established in 2009. The top of the Langhian Stage (the base of the Serravallian Stage) is at the first occurrence of fossils of the nanoplankton species ''Sphenolithus heteromorphus'' and is located in magnetic chronozone C5ABr. The Langhian is coeval w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
