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Proboscidean Datum Event
The Proboscidea (; , ) are 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. From the mid-Miocene onwards, most proboscideans were very large. The largest land mammal of all time may have been a proboscidean; ''Palaeoloxodon namadicus'' was up to at the shoulder and may have weighed up to , almost double the weight of some sauropods like ''Diplodocus carnegii''. The largest extant proboscidean is the African bush elephant, with a record of size of at the shoulder and . In addition to their enormous size, later proboscideans are distinguished by tusks and long, muscular trunks, which were less developed or absent in early proboscideans. Three species of elephant are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. Elephantidae is the only surviving family of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact and possibly volcanism, marked the beginning of the Paleocene and killed off 75% of living species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. In the Paleocene, the continents of the Northern Hemisphere were still connected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Largest Land Mammal
The following is a list of largest mammals by family. Tenrecs and allies (Afrosoricida) *The largest of these insectivorous mammals is the giant otter shrew (''Potamogale velox''), native to Central Africa. This species can weigh up to and measure in total length. Even-toed ungulates (Artiodactyla) *The largest species in terms of weight is the hippopotamus (''Hippopotamus amphibius''), native to the rivers of sub-Saharan Africa. They can attain a size of , long and tall. Prehistoric hippos such as '' H. gorgops'' and '' H. antiquus'' rivaled or exceeded the modern species as the largest members of the family and order to ever exist. *The longest-bodied species, and tallest of all living land animals, is the giraffe (''Giraffa sp.''), measuring up to tall to the top of the head, and despite being relatively slender, reaching a top weight of . *The largest extant representative of the bovids, a diverse and well-known family, is the Asian forest-dwelling gaur (''Bos ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphatherium
''Phosphatherium escuillei'' is a basal proboscidean that lived from the Late Paleocene to the early stages of the Ypresian age until the early Thanetian some 56 million years ago in North Africa. Research has suggested that ''Phosphatherium'' existed during the Eocene period. Description ''P. escuillei'' possessed rather flat features, centered around a low skull and a long, straight dorsal profile. The skull itself was rather disproportionate, consisting of an elongated cranial region and a rather short rostrum. The sagittal crest, the ridge along the dorsomedian line of its skull, spans across nearly half of the skull itself. The nasal cavity is high and wide, suggesting a large snout in life. One of the main factors of ''Phosphatherium'' body is its nontraditional musculoskeletal system. The shape of its head is composed of attributes of a snout, more vividly, turning into a mouth with a rounded jawline. Similar mammals in its order retained a more snout-like nose, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Column
A column or pillar in architecture and structural engineering is a structural element that transmits, through compression (physical), compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. The term ''column'' applies especially to a large round support (the shaft of the column) with a Capital (architecture), capital and a base or pedestal, which is made of stone, or appearing to be so. A small wooden or metal support is typically called a ''Post (structural), post''. Supports with a rectangular or other non-round section are usually called ''pier (architecture), piers''. For the purpose of wind engineering, wind or earthquake engineering, columns may be designed to resist lateral forces. Other compression members are often termed "columns" because of the similar stress conditions. Columns are frequently used to support Beam (structure), beams or arches on which the upper parts of walls or ceilings res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeoloxodon
''Palaeoloxodon'' is an extinct genus of elephant. The genus originated in Africa during the Pliocene era, and expanded into Eurasia during the Pleistocene era. The genus contains some of the largest known species of elephants, over four metres tall at the shoulders, including the European straight-tusked elephant (''Palaeoloxodon antiquus''), and the southern Asian '' Palaeoloxodon namadicus'', the latter of which was possibly the largest known land mammal based on fragmentary remains, but this requires proper reexamination. In contrast, the genus also contains many species of dwarf elephants that evolved via insular dwarfism on islands in the Mediterranean, some only a metre in height, making them the smallest elephants known. The genus has a long and complex taxonomic history, and at various times, it has been considered to belong to '' Loxodonta'' or '' Elephas'', but today is usually considered a valid and separate genus in its own right. Taxonomy In 1924, circumscribed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammoth
A mammoth is any species of the extinct elephantid genus ''Mammuthus'', one of the many genera that make up the order of trunked mammals called proboscideans. The various species of mammoth were commonly equipped with long, curved tusks and, in northern species, a covering of long hair. They lived from the Pliocene epoch (from around 5 million years ago) into the Holocene at about 4,000 years ago, and various species existed in Africa, Europe, Asia, and North America. They were members of the family Elephantidae, which also contains the two genera of modern elephants and their ancestors. Mammoths are more closely related to living Asian elephants than African elephants. The oldest representative of ''Mammuthus'', the South African mammoth (''M. subplanifrons''), appeared around 5 million years ago during the early Pliocene in what is now southern and eastern Africa. Descendant species of these mammoths moved north and continued to propagate into numerous subsequen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegodon
''Stegodon'' ("roofed tooth" from the Ancient Greek words , , 'to cover', + , , 'tooth' because of the distinctive ridges on the animal's molars) is an extinct genus of proboscidean, related to elephants. It was originally assigned to the family Elephantidae along with modern elephants but is now placed in the extinct family Stegodontidae. Like elephants, ''Stegodon'' had teeth with plate-like lophs that are different from those of more primitive proboscideans like gomphotheres and mastodons. The oldest fossils of the genus are found in Late Miocene strata in Asia, likely originating from the more archaic ''Stegolophodon,'' shortly afterwards migrating into Africa. While the genus became extinct in Africa during the Pliocene, ''Stegodon'' remained widespread in Asia until the end of the Pleistocene. Morphology Size Some species of ''Stegodon'' were amongst the largest proboscideans. ''S. zdanskyi'' is known from an old male (50-plus years old) from the Yellow River that is tal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gomphothere
Gomphotheres are any members of the diverse, extinct taxonomic family Gomphotheriidae. Gomphotheres were elephant-like proboscideans, but do not belong to the family Elephantidae. They were widespread across Afro-Eurasia and North America during the Miocene and Pliocene epochs and dispersed into South America during the Pleistocene following the Great American Interchange. Gomphotheriidae in its broadest sense is probably paraphyletic with respect to Elephantidae, which contains modern elephants. While most famous forms such as '' Gomphotherium'' had long lower jaws with tusks, which is the ancestral condition for the group, after these forms became extinct, the surviving gomphotheres had short jaws with either vestigial or no lower tusks (brevirostrine), looking very similar to modern elephants, an example of parallel evolution. By the end of the Early Pleistocene, gomphotheres became extinct in Afro-Eurasia, with the last two genera, ''Cuvieronius'' persisting in souther ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastodon
A mastodon ( 'breast' + 'tooth') is any proboscidean belonging to the extinct genus ''Mammut'' (family Mammutidae). Mastodons inhabited North and Central America during the late Miocene or late Pliocene up to their extinction at the end of the Pleistocene 10,000 to 11,000 years ago. They lived in herds and were predominantly forest-dwelling animals. They generally had a browsing diet, distinct from that of the contemporary Columbian mammoth, which tended towards grazing. ''M. americanum'', the American mastodon, and ''M. pacificus'', the Pacific mastodon, are the youngest and best-known species of the genus. Mastodons disappeared from North America as part of a mass extinction of most of the Pleistocene megafauna, widely believed to have been caused by a combination of climate changes at the end of the Pleistocene and overexploitation by Paleo-Indians. History A Dutch tenant farmer found the first recorded remnant of ''Mammut'', a tooth some in weight, in the village of C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asian Elephant
The Asian elephant (''Elephas maximus''), also known as the Asiatic elephant, is the only living species of the genus ''Elephas'' and is distributed throughout the Indian subcontinent and Southeast Asia, from India in the west, Nepal in the north, Sumatra in the south, and to Borneo in the east. Three subspecies are recognised—'' E. m. maximus'' from Sri Lanka, ''E. m. indicus'' from mainland Asia and '' E. m. sumatranus'' from the island of Sumatra. Formerly, there was also the Syrian elephant or Western Asiatic elephant (''Elephas maximus asurus'') which was the westernmost population of the Asian elephant (''Elephas maximus''). This subspecies became extinct in ancient times. Skeletal remains of ''E. m. asurus'' have been recorded from the Middle East: Iran, Iraq, Syria, and Turkey from periods dating between at least 1800 BC and likely 700 BC. It is one of only three living species of elephants or elephantids anywhere in the world, the others being the African bus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
African Forest Elephant
The African forest elephant (''Loxodonta cyclotis'') is one of the two living African elephant species. It is native to humid forests in West Africa and the Congo Basin. It is the smallest of the three living elephant species, reaching a shoulder height of . Both sexes have straight, down-pointing tusks, which erupt when they are 1–3 years old. It lives in family groups of up to 20 individuals. Since it forages on leaves, seeds, fruit, and tree bark, it has been referred to as the 'megagardener of the forest'. It contributes significantly to maintain the composition and structure of the Guinean Forests of West Africa and the Congolese rainforests. The first scientific description of the species was published in 1900. During the 20th century, overhunting caused a sharp decline in population, and by 2013 it was estimated that less than 30,000 individuals remained. It is threatened by habitat loss, fragmentation, and poaching. The conservation status of populations varies across ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
