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16.12.2015 19:18 - Encyclopedia Largest prehistoric animals Vol.1 Vertebrates part1 Mammals ch.5 Proboscideans-Mastodons and their four tusks relatives
Автор: valentint Категория: Забавление   
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Elephantimorpha
                   Family † Mammutidae
                                        Genus † Zygolophodon
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The third largest land mammal after the Palaeoloxodon namadicus and Indricotherium probably was Zygolophodon (Mammut borsoni).
Zygolophodon
is an extinct genus of African, Asian, North American and European mastodon that lived during the Miocene and Pliocene epochs. It may have evolved from Tetralophodon. While collecting fossils in the Clarno Formation of Oregon during 1941, noted paleobotanistsAlonzo W. Hancock and Chester A. Arnold recovered the most complete Zygolophodon skull known at the time.

It was one of the largest terrestrial mammals of all time. With a shoulder height of 4.1
-4.8 metres (13.5 ft-15ft) and a weight of 14–16 tonnes (15–18 short tons), it was approached the size of Paraceratherium, and was heavier than several sauropod dinosaurs.
A monstrous Mastodon which is nearly 3 times heavier than the extant African Elephant,weighing about 16 tonnes.It is the king of Tuskers.Zygolophodon had the longest tusks of any Proboscidean measuring upto 16 feet ! The Columbian Mammoth also had tusks upto 16 feet but it"s tusks were curved.
This animal was close to being the largest land mammal.
Two of the known specimens are not fully grown.If it had lived longer,it could surpass 18 tonnes.

 

                Genus † Mastodons,or Mammut
Mastodons are any species of extinct mammutidproboscideans in the genus Mammut, distantly related to elephants, that 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.Mastodons lived in herds and were predominantly forest dwelling animals that fed on a mixed diet obtained by browsing and grazing with a seasonal preference for browsing, similar to living elephants.

Mastodon americanus
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This unusual large mammal lived in North America during thePleistocene epoch until the end of the ice age. It roamed the earth for over a million years, but suddenly disappeared (perhaps because of the climate changes). It was one of the largest land animals living during the ice age. Mastodon belonged to the family Mammutidae, that originated in North Africa, spreading to Eurasia and entering North America 15 million years ago. Its name means "nipple tooth". These elephant-like animals were affected by environmental changes. Mastodons living during the middle of the last glaciation were small, whereas those living later in forests were larger. It was mostly adapted to conifer forests and marsh. It fed on plants (conifer twigs, swamp plants, larch, spruce, pine, grass, mosses, etc.) and used its tusks to break branches.
Mastodon had rather short, straight tusks and sharp cheek teeth. Females were smaller, their tusks were lighter and smaller than those of males. They had coats of fine underwool, overlain by abundant hair (2-7 inches in length). The average body size of the species M. americanum was around 2.3 m (7 ft 7 in) in height at the shoulders, corresponding to a large female or a small male, but large males could grow up to 2.8 m (9 ft 2 in) in height and weigh as much as 4.5 tonnes (5 short tons).However, the 35-year-old specimen AMNH 9950 could grow 2.89 metres (9.5 ft) tall and weighed 7.8 tonnes (7.7 long tons; 8.6 short tons), and another male grew 3.25 metres (10.7 ft) tall and weighed 11 tonnes (11 long tons; 12 short tons).
Fossils of mastodons are commonly found all over the North America and Canada. Mastodon americanus was first recognized in 1799 by well-known French anatomist Baron Cuvier.

Elephantida
                  Family †Gomphotheriidae
                                
Genus †Gnathabelodon
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Gnathabelodon is an extinct proboscidean (elephant) genus endemic to North America that includes species that lived during the Middle to Late Miocene. They were called "spoon-billed mastodons" since their lower jaw was elongated and shaped like a shoe-horn or spoon. The genus Gnathabelodon consists of two species: Thorpe"s spoon-billed mastodon (G. thorpei) and Buckner"s spoon-billed mastodon (G. buckneri). The flaring of the tip of their lower jaw was similar to that of the "shovel-tuskers" (Platybelodon and Amebelodon); however, Gnathabelodon species are distinct in having no lower tusks whilst the "shovel tuskers" have broad, flattened lower tusks. The upper tusks are large and curve outwards and upwards. In respects to dentition and overall body form, it was similar to other species of Gomphotherium.
As a gompothere elephant, Gnathabelodon differed from today’s elephants by having enlarged incisor teeth in the lower jaw that formed a ‘shovel’ protruding from the tip of the lower jaw. In the past Gnathabelodon has been considered to be the same elephant as the closely related
Gompotherium (the type genus of the Gomphotheriidae),though today Gnathabelodon is still usually treated as a distinct genus.

Genus † Choerolophodon
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Choerolophodon is an extinct genus of proboscid which lived during the Miocene of Eurasia .Here we report the first discovery of a relatively complete skull of Choerolophodon from the late early Miocene Dalanggou quarry of Linxia Basin, Gansu Province in China. The skull is low and elongated, with two enamel-less and outward-and-upward curved incisors and the choerolophodont molars. These characters indicate that the new specimen can be assigned to the genus Choerolophodon, as it is quite distinct from other common gomphotheres in northern China such as Gomphotherium, Platybelodon, and Sinomastodon. The skull is also primitive in possessing laterally-expanded zygomatic arches, anteriorly-positioned orbits, weakly-developed cheek teeth cement, and retention of a P4. Prior to this discovery, Choerolophodon was found primarily from the middle-late Miocene of Africa, Eastern Europe, and western and southern Asia. The discovery of this new material expands the known temporal and spatial distributions of this taxon and helps us better understand the phylogeny, evolution, and adaptive radiation of gomphotheres in early Miocene of China.

Genus † Gomphotherium
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Gomphotherium ("Welded Beast") is an extinct genus of proboscid that evolved in the Early Miocene of North America and lived for about 12.4 million years from 13.650—1.2 Ma.
The genus emigrated into Asia, Europe and Africa after a drop in sea level (probably during the Tortonian epoch) allowed them to cross over. It survived into the Pleistocene, and its remains have been found in Sweden, France, Germany, Austria, Croatia, Kansas, Tennessee, China, Pakistan, Kenya and Bosnia and Herzegovina.
G. productum is known from a 35-year-old male 2.51 metres (8.2 ft) tall weighing 4.6 tonnes (4.5 long tons; 5.1 short tons). Even larger is G. steinheimense, known from a complete 37-year-old male found in
Mьhldorf, Germany, which is 3.17 metres (10.4 ft) tall and weighed 6.7 tonnes (6.6 long tons; 7.4 short tons).
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Skeletal restoration of G. productum (right) and G. steinheimense (left)
It had four tusks, two on the upper jaw and two on the elongated lower jaw. The lower tusks are parallel and shaped like a shovel and were probably used for digging up food from mud. Unlike modern elephants, the upper tusks were covered by a layer of enamel. Compared to elephants, the skull was more elongated and low, indicating that the animal had a short trunk, rather like a tapir"s. These animals probably lived in swamps or near lakes, using their tusks to dig or scrape up aquatic vegetation. In comparison to earlier proboscids, Gomphotherium had far fewer molars
;the remaining ones had high ridges to expand their grinding surface. Gomphotherium inhabited dry wooded regions near lakes.

Subfamily †Amebelodontinae
                    Genus †Archaeobelodon
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Archaeobelodon is an extinct genus of proboscidea of the family Gomphotheriidae that lived in Egypt during the Miocene from 16.9—16.0 Ma, living for approximately 0.9 million years. Archaeobelodon was an ancestor of Platybelodon and Amebelodon. Archaeobelodon had a trunk and tusks. It reached a weight of about 2305 - 3477 kg, being smaller than a modern elephant.


Genus † Serbelodon
image

Serbelodon is an extinct genus of proboscidean. It was a gomphothere "shovel-tusker". It had tusks and a trunk. It lived in North America during the Miocene Epoch, and may have evolved from Amebelodon.
Serbelodon burnhami was named after Frederick Russell Burnham
the brother-in-law of the fossil"s discoverer John C. Blick.
Several species have been described from serbelodon :
Serbelodon barbourensis Frick , 1933
Serbelodon zhongningensis Guan 1986
Serbelodon burnhami Osborn , 1933
The type serbelodon burnhami was named in honor of the American Scouts Frederick Russell Burnham . You will now most of the genus amebelodon attributed.
The earliest evidence of serbelodon can be some 15 million years ago found in China , one of the oldest sites is Wudaoling Autonomous Region Ningxia . Before 12 million years, made ​​her first appearance in North America , but here it is only a few sites in California and Nebraska known . Recent evidence are present here with 8 million years in East Asia , it is probably extinct before 11 million years.


Genus † Amebelodon
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Amebelodon is a member of a diverse group of  gomphotheres, a group that also gave rise to the modern elephants and their close relative the mammoth. The most striking attribute of this animal is its lower tusks, which are narrow, elongated, and distinctly flattened with the degree of flattening varying among the different species.
Amebelodon first appeared in the Great Plains and Gulf Coast regions of North America during the late Miocene, roughly 9 million years ago, and apparently became extinct on this continent sometime around 6 million years ago. The youngest record of Amebelodon is from a 5-million-year-old site in North Africa. The species Amebelodon floridanus was relatively small, a little smaller than living elephants, and was common in fossil sites from 9 to 8 million years ago. Other larger but somewhat younger common North American species include Amebelodon fricki.One lineage of species once assigned to Amebelodon, including Amebelodon britti and North African Amebelodon cyrenaicus, is now placed in a separate genus called Konobelodon, formerly considered to be a subgenus. Like other typical gomphotheres, Amebelodon possessed two sets of tusks,two uppers (much like those found on modern elephants), and two lowers that extended from the very front of the lower jaws.

Genus † Platybelodon
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Platybelodon is an extinct genus of Proboscidea , who lived in the Miocene epoch about 15 million years ago .
Platybelodon had four tusks . In the upper jaw were shortened and directed obliquely forward and downward. The length of the lower jaw are both flat front incisor were fused and transformed into a kind of shovel . Platybelodon reach lengths of up to 6 meters and a height of 2.8 m . These animals live in herds and weigh up to 4.5 tons.
It is assumed that platybelodon inhabited the marshlands and savannahs pulled out his teeth with the help of shovel- trunk marsh plants . Platybelodon were close relatives amebelodonts .
In Europe, it was found and progenitor platybelodon - archaeobelodon .


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 




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