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16.12.2015 19:46 - Encyclopedia Largest prehistoric animals Vol.1 Vertebrates part1 Mammals ch.5 Proboscideans-Elephantidae,the closest giant relatives of modern elephants
Автор: valentint Категория: Забавление   
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Family † Elephantidae
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Genus † Stegotetrabelodon
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1. Stegotetrabelodon syrticus 2. Stegodon ganesha 3. Anancus arvernensis
Stegotetrabelodon is an extinct genus of primitive elephant with gomphothere-like anatomical features from the Late Miocene to Early Pliocene of Africa and Eurasia. The type species is S. syrticus of late Miocene Africa, which reached roughly 4 m (13 ft) in shoulder height and weight - 8000 kg.The other unequivocally recognized species is S. orbus, also of late Miocene Africa. Other species outside of Africa are questionably placed in this genus, including teeth from Late Miocene Hungary and Iran originally described as being of the Mastodon subgenus Bunolophodon, Chinese specimens originally described as being also of Mastodon, as well as of Tetralophodon and Stegodon, and a species from the late Miocene-aged Dokh Pathan Formation in Pakistan, S. maluvalensis.

This animal was very similar to the current elephants to the body shape and size, but they differed on some important features , mainly concerning the skull . Stegotetrabelodon had to be one of the most spectacular proboscidean ever lived : in fact had four tusks (instead of the two in current elephants ) , two in the upper jaw and two protruding from the jaw . The upper fangs were slightly curved upwards and provided with a thick layer of enamel , while the lower defenses were also long , but straight and almost devoid of enamel.

Genus † Primelephas
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Primelephas is a genus of Elephantinae that existed during the Miocene and Pliocene epochs,fossils found in Africa in Chad , Kenya, Tanzania , Uganda and Ethiopia.. The name of the genus suggests "first elephant". These primitive elephantids are hypothesised to be the common ancestor of Mammuthus, the mammoths, and the closely allied genera Elephas and Loxodonta, the African and Eurasian elephants, diverging some four to six million years ago. Unusual for an elephant, it had four tusks. The type species, Primelephas gomphotheroides, was described by Vincent Maglio in 1970, the specific epithet indicating the fossil specimens were gomphothere-like.Another type , Primelephas korotorensis Coppens, in 1965 , was described by 5 years earlier , originally as Stegodon korotorensis, and is named after the area Koro Toro in Chad , which found its fossils (as well as the remains of some other animals ) . In 1973 Maglio has assigned this species to the genus Primelephas.

Tribe † Loxodontini
                 Genus † Loxodonta
Loxodonta is one of two existing genera of the family, Elephantidae.African elephants are elephants of the genus Loxodonta from Greek loxуs "slanting, crosswise, oblique sided" + odoъs, stem odуnt-, "tooth". The genus consists of two extant species: the African bush elephant and the smaller African forest elephant. Fossil remains of Loxodonta have been found only in Africa, in strata as old as the middle Pliocene.

Loxodonta adaurora is an extinct species of elephant in the genus Loxodonta, that of the African elephants.
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Fossils of Loxodonta adaurora have only been found in Africa, where they developed in the Pliocene. L. adaurora was presumed to be the genetic antecedent of the two modern African elephant species; however, an analysis in 2009 suggested that L. africana
evolved from L. atlantica.


Loxodonta atlantica
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Loxodonta atlantica is an extinct species of elephant in the genus Loxodonta, from Africa. It was larger than the modern
African Elephant, with more progressive dentition. This animal measured 4,2 m. higt t the shoulder, and weighet an 10 000 kg.It includes Pleistocene fossils from Ternifine, Middle Pleistocene fossils from Elandsfontein and Late Pliocene fossils from the Omo. L. atlantica was said to probably derive from L. adaurora; however, an analysis in 2009 suggested that L. antlantica evolved from L. exoptata, and is ancestral to L. africana. The species is divided into two subspecies: L. atlantica atlantica (northern Africa) and L. atlantica zulu (southern Africa). The type for Loxodonta atlantica is housed in the Musйum national d"histoire naturelle in Paris, but is listed without a specimen number.


Tribe † Elephantini

                 Genus † Palaeoloxodon
Palaeoloxodon is an extinct genus that contains the various species of straight-tusked elephant. Its species" remains have been found in Bilzingsleben, Germany; Cyprus; Japan; Sicily; Malta; and in England during the excavation of the second Channel Tunnel. The English discovery, in 2006 in northwest Kent, dated c. 400,000 ybp, was of a single adult; associated with it were Palaeolithic stone butchering tools of the type used by Homo heidelbergensis. One species, Palaeoloxodon namadicus, was the largest known land mammal of all time.
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Palaeoloxodon namadicus or the Asian straight-tusked elephant, was a species of prehistoric elephant that ranged throughout Pleistocene Asia, from India (where it was first discovered) to Japan, where the indigenous Neolithic cultures hunted that particular subspecies for food. It is a descendant of the straight-tusked elephant.
Some authorities regard it to be a subspecies of Palaeoloxodon antiquus, the straight-tusked elephant, due to extreme similarities of the tusks. Their skull structure was also different from that of a modern elephant.
Several studies have attempted to estimate the size of the Asian straight-tusked elephants, as well as other prehistoric proboscideans, usually using comparisons of thigh bone length and knowledge of relative growth rates to estimate the size of incomplete skeletons.
One partial skeleton found in India in 1905 had thigh bones that likely measured 160 centimetres (5.2 ft) when complete, suggesting a total shoulder height of 4.3 metres (14 ft) and weight of 14 tonnes (14 long tons; 15 short tons) for this individual elephant.
Two partial thigh bones were found in the 19th century and would have measured 155 cm (5.1 ft) when complete. A fragment from the same locality was said to be almost a quarter larger; volumetric analysis then yields a size estimate of 5 metres (16 ft) tall at the shoulder and 22 tonnes (24 short tons) in weight. This makes P. namadicus the largest land mammal of all time, surpassing the largest indricotheres and up to twice the size of the well-known dinosaurDiplodocus carnegii. (units:tonnes = 1000 kilograms, long ton= 2,240 pounds, short ton=2000 pounds)

The straight-tusked elephant (Palaeoloxodon antiquus) is an extinct species of elephant closely related to the living Asian elephant. It inhabited Europe during the Middle and Late Pleistocene (781,000–50,000 years before present). Some experts regard the larger Asian species, Palaeoloxodon namadicus, as a variant or subspecies.
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Palaeoloxodon antiquus was quite large, individuals reaching 4 metres (13 ft) in height. One 40-year-old male was 3.81 metres (12.5 ft) tall and weighed 11.3 tonnes (11.1 long tons; 12.5 short tons), while another from Montreuil weighed about 15 tonnes (15 long tons; 17 short tons) and was 4.2 metres (14 ft) tall and had long, slightly upward-curving tusks.P. antiquus"s legs were slightly longer than those of modern elephants. This elephant is thought to have had an 80-cm-long tongue that could be projected a short distance from the mouth to grasp leaves and grasses.With this tongue and a flexible trunk, straight-tusked elephants could graze or browse on Pleistocene foliage about 8 m above ground.
Straight-tusked elephants lived in small herds of about five to 15 individuals.They preferred warm conditions and flourished in the interglacial periods during the current Ice Age, spreading from continental Europe to Great Britain during the warmer periods. It is assumed that they preferred wooded environments. During colder periods, the species migrated south. It became extinct in Britain by the beginning of the last glacial, about 115,000 years ago. Eventually it was replaced by the mammoth.

Palaeoloxodon recki
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Palaeoloxodon recki is an
extinct species related to the Asian elephant Elephas maximus. At up to 14 feet (4.27 metres) in shoulder height, it was one of the largest elephant species to have ever lived. It is believed that P. recki ranged throughout Africa between 3.5 and 1 million years ago. The Asian Elephant is the closest living relative of P. recki. P. recki was a successful grass eating elephant that lived throughout the Pliocene and the Pleistocene until it was pushed to extinction, perhaps by competition with members of the genus Loxodonta, the African elephants of today. An male of P. recki from Koobi Fora was 40 years old when it died. At that age it was 4.27 metres (14.0 ft) tall and weighed 12.3 tonnes (12.1 long tons; 13.6 short tons).


Genus †  Elephas
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The Syrian elephant or Western Asitic elephant (Elephas maximus asurus) is a proposed name for the westernmost population of the
Asian elephant (Elephas maximus), which became extinct in ancient times.Skeletal remains of E. m. asurus have been recorded from the Middle East (Turkey, Iraq and Syria) from periods dating between 3 million years BC and 100 years BC.
Ancient Syrian craftsmen used the tusks of E. m. asurus to make ivory carvings. In Syria, the production of ivory items was at its maximum during the first millennium BC, when the Arameans made splendid ivory inlay for furniture. This overhunting of Syrian elephants for ivory ultimately resulted in their extinction by around 100 BC.
Syrian elephants were among the largest Asian elephant subspecies to have survived into historic times, measuring 3.5 metres (11 ft 6 in) or more at the shoulder. Skeletal remains show it did not differ much from the Indian subspecies, except in size.

imageElephas ekorensis is an extinct species of large herbivorous mammals belonging to the Elephantidae family. Fossils have been found in East Africa dating as far back as the Early Pliocene age, between 5.3 and 3.6 million years ago. It is the earliest recognisable species in the Elephas genus. There are two lineages, a dead-end, Afro-Eurasian lineage and an Asian lineage that evolved into modern Asian elephants. It was an ancestor of Elephas recki and Elephas iolensis.

Elephas iolensis is an extinct species of large herbivorous mammal belonging to the Elephantidae family. The type specimen is located in the National Museum of Natural History in Paris.The species is thought to have lived in the African Savannah during the Late Pleistocene age, between 130,000 and 10,000 years ago. It was a direct descendant of Elephas recki and more distantly, Elephas ekorensis
 


Genus † Archidiscodon

Southern mammoth (Archidiskodon meridionalis)
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Mammuthus meridionalis, or the southern mammoth, is an extinct species of mammoth endemic to Europe and central Asia from the Pleistocene, living from 2.5–1.5 mya. With a height of about 4 m. and estimated weight of 10 tons, M. meridionalis is one of the largest proboscideans to have ever lived, along with other larger species of mammoth, and the earlier Deinotherium. It had robust twisted tusk, common of mammoths. Its molars had low crowns and a small number of thick enamel ridges, adapted to a woodland diet of leaves and shrubs, this indicates it lived on a relatively warm climate which makes more probable that it lacked dense fur. Plant and fossils found with the remains show that M. meridionalis was living in a time of mild climate, generally as warm or slightly warmer than Europe experiences today. Deciduous mixed wood provided its habitad and food, which compromised mostly of tree-browse: oak, ash, beech and other familiar European trees, as well as some that are now exotic to the region, such as hemlock, wing nut and hickory. A complete skeleton is in Stavropol State Museum. Further east, discoveries at Ubeidiyah (Israel) and Dmanisi (Georgia) show the early mammoth living in a partially open habitat with grassy areas, though subsisting on scattered trees and shrubs.









 

 

 

 




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