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Macrauchenia
''Macrauchenia'' ("long llama", based on the now-invalid llama genus, ''Auchenia'', from Greek "big neck") is an extinct genus of large ungulate native to South America from the Pliocene or Middle Pleistocene to the end of the Late Pleistocene. It is a member of the extinct order Litopterna, a group of South American native ungulates distinct from the two orders which contain all living ungulates which had been present in South America since the early Cenozoic, over 60 million years ago, prior to the arrival of living ungulates in South America around 2.5 million years ago as part of the Great American Interchange. The bodyform of ''Macrauchenia'' has been described as similar to a camel, being one of the largest-known litopterns, with an estimated body mass of around 1 tonne. The genus gives its name to its family, Macraucheniidae, which like ''Macrauchenia'' typically had long necks and three-toed feet, as well as a retracted nasal region, which in ''Macrauchenia'' manifests as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litopterna
Litopterna (from "smooth heel") is an extinction, extinct order of South American native ungulates that lived from the Paleocene to the Pleistocene-Holocene around 62.5 million to 12,000 years ago (or possibly as late as 3,500 years ago), and were also present in Antarctica during the Eocene. They represent the second most diverse group of South American ungulates after Notoungulata. It is divided into nine families, with Proterotheriidae and Macraucheniidae being the most diverse and last surviving families. Diversity The body forms of many litopterns, notably in the limb and skull structure, are broadly similar to those of living ungulates, unlike other South American native ungulate groups, which are often strongly divergent from living ungulates. Paleocene and Eocene litopterns generally had small body masses, with ''Protolipterna'' (Protolipternidae) estimated to have had a body mass of , though the Eocene Sparnotheriodontidae, sparnotheriodontids were considerably large ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Macraucheniidae
Macraucheniidae is a family in the extinct South American ungulate order Litopterna, that resembled camelids. They had three functional digits on the fore and hind feet, as well as elongate necks. The family is generally divided up into two subfamilies, Cramaucheniinae (which may be paraphyletic) and Macraucheniinae. The family shows retraction of the nasal region, most extremely to the top of the skull in derived macraucheniine taxa like ''Macrauchenia.'' which has been interpreted to have supported a probsocis, perhaps like that of a saiga antelope to filter dust, or a moose-like prehensile lip. The earliest unambiguous members of the family date to the late Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ... around 30 million years ago. '' Polymorphis'' from the Eoce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenorhinotherium
''Xenorhinotherium'' is an extinct genus of macraucheniine macraucheniids, native to northern South America during the Pleistocene and Holocene epoch, closely related to ''Macrauchenia'' of Patagonia. The type species is ''X. bahiense''.''Xenorhinotherium'' at .org Taxonomy Some authors have proposed that the genus ''Xenorhinotherium'' a synonym of ''Macrauchenia'', though this has not been widely accepted. The name ''Xenorhinotherium'' means "Strange-Nosed Beast" and ''bahiense'' refers to the Brazilian state of |
Great American Interchange
The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land and freshwater fauna (animals), fauna migrated from North America to South America via Central America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor, forming a land bridge between the previously separated continents. Although earlier dispersals had occurred, probably over water, the migration accelerated dramatically about 2.7 million years (Ma (unit), Ma) ago during the Piacenzian age. It resulted from the joining of the Neotropical realm, Neotropic (roughly South American) and Nearctic realm, Nearctic (roughly North American) biogeographic realms definitively to form the Americas. The interchange is visible from observation of both biostratigraphy and nature (neontology). Its most dramatic effect is on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pampas
The Pampas (; from Quechua 'plain'), also known as the Pampas Plain, are fertile South American low grasslands that cover more than and include the Argentine provinces of Buenos Aires, La Pampa, Santa Fe, Entre Ríos, and Córdoba; all of Uruguay; and Brazil's southernmost state, Rio Grande do Sul. The vast plains are a natural region, interrupted only by the low Ventana and Tandil hills, near Bahía Blanca and Tandil (Argentina), with a height of and , respectively. This ecoregion has been changed by humans, especially since the release of animals like cattle, pigs, and especially sheep onto these plains. The climate is temperate, with precipitation of that is more or less evenly distributed throughout the year, making the soils appropriate for agriculture. The area is also one of the distinct physiography provinces of the larger Paraná–Paraguay plain division. It is considered that the limit of the Pampas plain is to the north with the Atlantic Forest and the G ... [...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] |
Second Voyage Of HMS Beagle
The second voyage of HMS ''Beagle'', from 27 December 1831 to 2 October 1836, was the second survey expedition of HMS Beagle, HMS ''Beagle'', made under her newest commander, Robert FitzRoy. FitzRoy had thought of the advantages of having someone onboard who could investigate geology, and sought a natural history, naturalist to accompany them as a wikt:supernumerary, supernumerary. At the age of 22, the graduate Charles Darwin hoped to see the tropics before becoming a parson, and accepted the opportunity. He was greatly influenced by reading Charles Lyell's ''Principles of Geology'' during the voyage. By the end of the expedition, Darwin had made his name as a geologist, and fossil collector, and the publication of his journal (later known as ''The Voyage of the Beagle'') gave him wide renown as a writer. ''Beagle'' sailed across the Atlantic Ocean, and then carried out detailed hydrographic surveys around the coasts of southern South America, returning via Tahiti and Australia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patagonia
Patagonia () is a geographical region that includes parts of Argentina and Chile at the southern end of South America. The region includes the southern section of the Andes mountain chain with lakes, fjords, temperate rainforests, and glaciers in the west and Patagonian Desert, deserts, Plateaus, tablelands, and steppes to the east. Patagonia is bounded by the Pacific Ocean on the west, the Atlantic Ocean to the east, and many bodies of water that connect them, such as the Strait of Magellan, the Beagle Channel, and the Drake Passage to the south. The northern limit of the region is not precisely defined; the Colorado River, Argentina, Colorado and Barrancas River, Barrancas rivers, which run from the Andes to the Atlantic, are commonly considered the northern limit of Argentine Patagonia. The archipelago of Tierra del Fuego is sometimes considered part of Patagonia. Most geographers and historians locate the northern limit of Chilean Patagonia at Huincul Fault, in Araucanía R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South American Native Ungulates
South American native ungulates, commonly abbreviated as SANUs, are extinct ungulate-like mammals that were indigenous to South America from the Paleocene (from at least 63 million years ago) until the end of the Late Pleistocene (~12,000 years ago). They represented a dominant element of South America's Cenozoic terrestrial mammal fauna prior to the arrival of living ungulate groups in South America during the Pliocene and Pleistocene as part of the Great American Interchange. They comprise five major groups conventionally ranked as orders— Astrapotheria, Litopterna, Notoungulata, Pyrotheria, and Xenungulata—as well as the primitive " condylarth" groups Didolodontidae and Kollpaniinae. It has been proposed that some or all of the members of this group form a clade, named Meridiungulata, though the relationships of South American ungulates remain largely unresolved. The two largest groups of South American ungulates, the notoungulates and the litopterns, were the only grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English Natural history#Before 1900, naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended from a Common descent, common ancestor is now generally accepted and considered a fundamental scientific concept. In a joint presentation with Alfred Russel Wallace, he introduced his scientific theory that this Phylogenetics, branching pattern of evolution resulted from a process he called natural selection, in which the struggle for existence has a similar effect to the artificial selection involved in selective breeding.. Darwin has been described as one of the most influential figures in human history and was honoured by Burials and memorials in Westminster Abbey, burial in Westminster Abbey. Darwin's early interest in nature led him to neglect his medical education at the University of Edinburgh Medical Schoo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Port St Julian
A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manchester and Duluth; these access the sea via rivers or canals. Because of their roles as ports of entry for immigrants as well as soldiers in wartime, many port cities have experienced dramatic multi-ethnic and multicultural changes throughout their histories. Ports are extremely important to the global economy; 70% of global merchandise trade by value passes through a port. For this reason, ports are also often densely populated settlements that provide the labor for processing and handling goods and related services for the ports. Today by far the greatest growth in port development is in Asia, the continent with some of the world's largest and busiest ports, such as Singapore and the Chinese ports of Shanghai and Ningbo-Zhoushan. As of 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
