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Deinotheriidae Temporal range: Late Oligocene-Early Pleistocene | |
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Deinotherium | |
Life restoration of Deinotherium bozasi | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Proboscidea |
Suborder: | † Plesielephantiformes |
Family: | † Deinotheriidae Bonaparte, 1845 |
Type genus | |
† Deinotherium Kaup, 1829 | |
Genera | |
Subfamily †Chilgatheriinae Subfamily †Deinotheriinae |
Deinotheriidae ("terrible beasts") is a family of prehistoric elephant-like proboscideans that lived during the Cenozoic era, first appearing in Africa during the Oligocene then spreading across Europe and the lower latitudes of Asia during the Miocene epoch. Their most distinctive features were their lack of upper tusks and downward-curving tusks on the lower jaw.
Deinotheres were not very diverse; the only three known genera are Chilgatherium , Prodeinotherium , and Deinotherium . These form an evolutionary succession, with each new genus replacing the preceding one. Deinotheres were relatively conservative and showed little morphological change over their evolution, aside from a progressive increase in body size. Some species of Deinotherium are among the largest known land mammals ever, considerably exceeding modern elephants in size. The last members of Deinotherium persisted until the end of the Early Pleistocene in Africa, around 1 million years ago.
The body shape and proportions of deinotheres were very much like those of modern elephants. The legs were long, like modern elephants, but the skull was rather flatter than that of true elephants. The upper jaw lacked incisor and canine teeth, but possessed five low-crowned molars on each side, with the same number in the lower jaw. Deinotheres used their front teeth for crushing their food, and the back teeth for shearing (slicing) the plant material. [1] The front part of the lower jaw was turned downwards and bore the two tusk-like incisors. These curved downwards and backwards in a sort of huge hook and constituted the most distinct feature of the deinotheres. The tusks were used to strip vegetation rather than for digging. [1]
While the earliest deinothere Chilgatherium probably weighed only around 1.5 tonnes (3,300 lb) and was less than 2 metres (6.6 ft) tall, some species of Deinotherium represent among the largest known proboscideans, with shoulder heights of over 4 metres (13 ft) and body masses around 12 tonnes (26,000 lb), considerably exceeding living African bush elephants in body size, making them among the largest land mammals ever. [2]
Deinotheres were "shearing browsers" adapted for feeding on plants above ground level. [1] The way they chewed their food was probably similar to that of modern tapirs, with the front teeth being used to crush the food, while the second and third molars have a strong vertical shearing action, with little lateral (side-to-side) movement. This chewing action differs from both that of gomphotheres (lateral grinding) and elephants (horizontal shearing). Deinothere molars show little wear, indicating a diet of soft, non-gritty, forest vegetation, with the down-turned lower tusks being used for stripping bark or other vegetation. [1]
Deinotherium giganteum has a more elongated lower fore limb than early and middle Miocene Prodeinotherium, indicating a more efficient stride as an adaptation to the spread of savannas in Europe during the late Miocene. Deinotheres probably migrated from forest to forest, traversing the wide and (to them) useless grasslands.
Deinotheriids are thought to have diverged away from the ancestors of Elephantiformes during the Eocene, over 40 millon years ago, based on the presence of primitive Elephantiformes in Lutetian deposits. [3] Phylogeny of Proboscidea showing placement of Deinotheriidae, following Hautier et al. 2021: [3]
The oldest known deinothere is Chilgatherium harrisi from the late Oligocene, around 27-28 million years ago. Its fossil remains have been found in the district of Chilga in Ethiopia (hence the name). It is primarily known from tooth remains. [2] [4]
By the early Miocene, deinotheres had grown to the size of a small elephant and had migrated to Eurasia. Several species are known, all belonging to the genus Prodeinotherium.
During the late middle Miocene, these modest-seized proboscideans were replaced by much larger forms across Eurasia. In Europe, Prodeinotherium bavaricum appeared in the early Miocene mammal faunal zone MN 4, but was soon replaced by Deinotherium giganteum in the middle Miocene. Likewise in Asia, Prodeinotherium is known from the early Miocene strata in the Bugti Hills, and continued into the middle Miocene Chinji Formation, where it was replaced by D. indicum.
While these Miocene deinotheres were dispersed widely and evolved to huge elephant sizes, they were not as common as the contemporary (but smaller) Elephantoidea. Fossil remains of this age are known from the France, Germany, Greece, Malta, and northern India and Pakistan. These consist chiefly of teeth and the bones of the skull.
After the extinction of the paraceratheres at the Oligocene-Miocene transition, the deinotheres were (and remained) the largest animals walking the Earth.
The late Miocene was the heyday of the giant deinotheres. D. giganteum was common from Vallesian and Turolian localities in Europe. Prodeinotherium, which was reasonably well represented in the early Miocene of Africa, was succeeded by D. bozasi at the beginning of the late Miocene. And in Asia, D. indicum was most common in the late-Miocene Dhok Pathan Formation.
Fossil teeth of D. giganteum, from the late-Miocene Sinap Formation at the Turkish site of Kayadibi are larger than those from older localities, such as Eppelsheim, Wissberg, and Montredon, indicating a tendency for increasing size of members of the species over time. These were the biggest animals of their day, protected from both predators and rival herbivores by virtue of their huge bulk. The largest mammoths did not approach them in size until the Pleistocene.
With the end of the Miocene, deinothere fortunes declined. D. indicum died out about 7 million years ago, possibly driven to extinction by the same process of climate change that had previously eliminated the even more enormous Paraceratherium . While in Europe, D. giganteum continued, albeit with dwindling numbers, until the middle Pliocene; the most recent specimen is from Romania.
In its original African homeland, Deinotherium continued to flourish throughout the Pliocene, and fossils have been uncovered at several of the African sites where remains of hominids have also been found.
The last deinothere species to become extinct was D. bozasi. The youngest known specimens are from the Kanjera Formation, Kenya, about 1 million years ago (early Pleistocene). The causes of the extinction of such a successful and long-lived animal are not known, although a small number of other species of African megafauna also died out at this time.
A mammoth is any species of the extinct elephantid genus Mammuthus. They lived from the late Miocene epoch into the Holocene until about 4,000 years ago, with mammoth species at various times inhabiting Africa, Asia, Europe, and North America. Mammoths are distinguished from living elephants by their spirally twisted tusks and in at least some later species, the development of numerous adaptions to living in cold environments, including a thick layer of fur.
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.
A mastodon is a member of the genus Mammut, which was endemic to North America and lived from the late Miocene to the early Holocene. Mastodons belong to the order Proboscidea, the same order as elephants and mammoths. Mammut is the type genus of the extinct family Mammutidae, which diverged from the ancestors of modern elephants at least 27–25 million years ago, during the Oligocene.
Deinotherium is an extinct genus of large, elephant-like proboscideans that lived from about the middle-Miocene until the early Pleistocene. Although its appearance is reminiscent of modern elephants, Deinotherium possessed a notably more flexible neck, with limbs adapted to a more cursorial lifestyle, as well as tusks which grew down and curved back from the mandible, as opposed to the forward-growing maxillary tusks of extant elephants. Deinotherium was a widespread genus, ranging from East Africa, north to Southern Europe, and east to the Indian subcontinent. They were primarily browsing animals, with a diet largely consisting of leaves. The genus most likely went extinct due to environmental changes, such as forested areas gradually being replaced by open grasslands, during the latter half of the Neogene. Deinotherium thrived the longest in Africa, where they survived until the end of the Early Pleistocene, around 1 million years ago.
Elephantidae is a family of large, herbivorous proboscidean mammals collectively called elephants and mammoths. In some cases, all members of the family can be referred to as elephants. They are large terrestrial mammals with a snout modified into a trunk and teeth modified into tusks. Most genera and species in the family are extinct. Only two genera, Loxodonta and Elephas, are living.
Mammutidae is an extinct family of proboscideans belonging to Elephantimorpha. It is best known for the mastodons, which inhabited North America from the Late Miocene until their extinction at the beginning of the Holocene, around 11,000 years ago. The earliest fossils of the group are known from the Late Oligocene of Africa, around 24 million years ago, and fossils of the group have also been found across Eurasia. The name "mastodon" derives from Greek, μαστός "nipple" and ὀδούς "tooth", referring to their characteristic teeth.
Moeritherium is an extinct genus of basal proboscideans from the Eocene of North and West Africa. The first specimen was discovered in strata from the Fayum fossil deposits of Egypt. It was named in 1901 by Charles William Andrews, who suggested that it was an early proboscidean, perhaps ancestral to mastodons, although subsequent workers considered it everything from a relative of manatees to a close relative of both clades' common ancestor. Currently, Moeritherium is seen as a proboscidean that, while fairly basal, predates the split between elephantiforms and deinotheres. Seven species have been named, though only three, are currently considered valid.
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.
Arsinoitherium is an extinct genus of paenungulate mammals belonging to the extinct order Embrithopoda. It is related to elephants, sirenians, and hyraxes. Arsinoitheres were superficially rhinoceros-like herbivores that lived during the Late Eocene and the Early Oligocene of North Africa from 36 to 30 million years ago, in areas of tropical rainforest and at the margin of mangrove swamps. A species described in 2004, A. giganteum, lived in Ethiopia about 27 million years ago.
Prodeinotherium is an extinct representative of the family Deinotheriidae that lived in Africa, Europe, and Asia in the early and middle Miocene. Prodeinotherium, meaning "before terrible beast", was first named in 1930, but soon after, the only species in it, P. hungaricum, was reassigned to Deinotherium. During the 1970s, however, the two genera were once again separated, with Prodeinotherium diagnosed to include Deinotherium bavaricum, Deinotherium hobleyi, and Deinotherium pentapotamiae, which were separated based on geographic location. The three species are from Europe, Africa, and Asia, respectively. However, because of usage of few characters to separate them, only one species, P. bavaricum, or many more species, including P. cuvieri, P. orlovii, and P. sinense may be possible.
Chilgatherium is the earliest and most primitive representative of the family Deinotheriidae. It is known from late Oligocene fossil teeth found in the Ethiopian district of Chilga.
Paraceratherium is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the early to late Oligocene epoch. The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. Paraceratherium means "near the hornless beast", in reference to Aceratherium, the genus in which the type species P. bugtiense was originally placed.
Phiomia, is an extinct genus of basal elephantiform proboscidean that lived in what is now Northern Africa during the Late Eocene to Early Oligocene some 37–30 million years ago. The type specimen of Phiomia, part of the mandible, was described in 1902 by Charles William Andrews and Hugh John Llewellyn. Unsure of its identity, they assigned it, tentatively, to the obsolete order Creodonta. Subsequently, it was recognised as a proboscidean. Briefly it was treated as a junior synonym of Palaeomastodon, but the two are regarded as separate genera. Though five species have been assigned to Phiomia over the years, only two, P. serridens and P. major, are currently recognised.
Gomphotherium 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.
Anancus is an extinct genus of "tetralophodont gomphothere" native to Afro-Eurasia, that lived from the Tortonian stage of the late Miocene until its extinction during the Early Pleistocene, roughly from 8.5–2 million years ago.
Phosphatherium escuillei Gheerbrant, Sudre et Cappetta 1996 is a basal proboscidean that lived in Africa during the early Eocene, by 56-55 Ma. It is one of the earliest known proboscidean, together with Eritherium azzouzorum from the Selandian. It was found in phosphorites beds from the base of the Ypresian stage of the Ouled Abdoun Basin, which is best known for its exceptionally rich marine vertebrate fauna.
Tetralophodon is an extinct genus of "tetralophodont gomphothere" belonging to the superfamily Elephantoidea, known from the Miocene of Afro-Eurasia.
Zygolophodon is an extinct genus of mammutid proboscidean that lived during the Miocene in Africa, Eurasia, and North America.
Notiomastodon is an extinct genus of gomphothere proboscidean, endemic to South America from the Pleistocene to the beginning of the Holocene. Notiomastodon specimens reached a size similar to that of the modern Asian elephant, with a body mass of 3-4 tonnes. Like other brevirostrine gomphotheres such as Cuvieronius and Stegomastodon, Notiomastodon had a shortened lower jaw and lacked lower tusks, unlike more primitive gomphotheres like Gomphotherium.
"Mammut" borsoni is an extinct species of mammutid proboscidean known from the Late Miocene to Early Pleistocene of Eurasia, spanning from western Europe to China. It is the last known mammutid in Eurasia, and amongst the largest of all proboscideans and largest known land mammals.
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