Pediolophodon Temporal range: | |
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Fossilized teeth of Pediolophodon campester | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Proboscidea |
Superfamily: | Elephantoidea |
Genus: | † Pediolophodon Lambert, 2007 |
Type species | |
Tetralophodon campester Cope, 1877 | |
Other species | |
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Pediolophodon is an extinct gomphotheriid proboscidean genus [1] from the middle to late Miocene of North America (Nebraska and Texas). Pediolophodon was a close relative of elephants (members of the Elephantinae subfamily of Elephantidae) and would have appeared superficially similar to them, but was not itself a true elephant.
Two species are recognized, P. campester and P. fricki. Both were originally assigned to the Old World genus Tetralophodon , but discoveries in the Kepler Quarry, Nebraska, showed these taxa to be generically distinct. [2] [3] [1]
Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantidae and the order Proboscidea; extinct relatives include mammoths and mastodons. Distinctive features of elephants include a long proboscis called a trunk, tusks, large ear flaps, pillar-like legs, and tough but sensitive grey skin. The trunk is prehensile, bringing food and water to the mouth and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears and convex or level backs.
A mammoth is any species of the extinct elephantid genus Mammuthus. The various species of mammoth were commonly equipped with long, curved tusks. They lived from the Pliocene epoch into the Holocene about 4,000 years ago, and various species existed in Africa, Europe, Asia, and North America. Mammoths are more closely related to living Asian elephants than African elephants.
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. 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 5.2 m (17.1 ft) at the shoulder and may have weighed up to 22 t, 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 4 m (13.1 ft) at the shoulder and 10.4 t. 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.
Homotherium is an extinct genus of machairodontine scimitar-toothed cat that inhabited North America, South America, Eurasia, and Africa during the Pliocene and Pleistocene epochs from around 4 million to 12,000 years ago. In comparison to Smilodon, the canines of Homotherium were shorter, and it was probably adapted to running down rather than ambushing prey.
A mastodon is any proboscidean belonging to the extinct genus Mammut. Mastodons inhabited North and Central America from the late Miocene up to their extinction at the end of the Pleistocene 10,000 to 11,000 years ago.
Elephantidae is a family of large, herbivorous proboscidean mammals collectively called elephants and mammoths. These 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.
Elephant birds are extinct flightless birds belonging to the order Aepyornithiformes that were native to the island of Madagascar. They are thought to have become extinct during the late 1st millennium to early 2nd millennium AD, likely as a result of human activity. Elephant birds comprised three species, one in the genus Mullerornis, and two in Aepyornis.Aepyornis maximus is possibly the largest bird to have ever lived, with their eggs being the largest known for any amniote. Elephant birds are palaeognaths, and their closest living relatives are kiwi, suggesting that ratites did not diversify by vicariance during the breakup of Gondwana but instead convergently evolved flightlessness from ancestors that dispersed more recently by flying.
Mammutidae is an extinct family of proboscideans that appeared during the Oligocene epoch and survived until the start of the Holocene. Mammutids ranged very widely, with fossils found in North America, Africa, and throughout Eurasia. The family was first described in 1922, classifying fossil specimens of the type genus Mammut (mastodons), and has since been placed in various arrangements of the order. The name "mastodon" derives from Greek, μαστός "nipple" and ὀδούς "tooth", as with the genus, referring to their characteristic teeth that distinguishes them from other proboscideans.
Elephas is one of two surviving genera in the family of elephants, Elephantidae, with one surviving species, the Asian elephant, Elephas maximus.
Palaeoloxodon is an extinct genus of elephant. The genus originated in Africa during the Pliocene, and expanded into Eurasia during the Pleistocene. The genus contains some of the largest known species of elephants, over 4 metres (13 ft) tall at the shoulders, including the European straight-tusked elephant and the South Asian Palaeoloxodon namadicus, the latter of which has been suggested to be the largest known land mammal based on extrapolation from fragmentary remains, though these estimates are highly speculative. In contrast, the genus also contains many species of dwarf elephants that evolved via insular dwarfism on islands in the Mediterranean, some only 1 metre (3.3 ft) 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.
African elephants are members of the genus Loxodonta comprising two living elephant species, the African bush elephant and the smaller African forest elephant. Both are social herbivores with grey skin, but differ in the size and colour of their tusks and in the shape and size of their ears and skulls.
The Columbian mammoth is an extinct species of mammoth that inhabited the Americas as far north as the Northern United States and as far south as Costa Rica during the Pleistocene epoch. The Columbian mammoth descended from the Eurasian mammoths that colonised North America around 1.5 million years ago, that later hybridised with woolly mammoths during the Middle Pleistocene, prior to 420,000 years ago. The Columbian mammoth was among the last mammoth species, and the pygmy mammoths evolved from them on the Channel Islands of California. The closest extant relative of the Columbian and other mammoths is the Asian elephant.
The straight-tusked elephant is an extinct species of elephant that inhabited Europe and Western Asia during the Middle and Late Pleistocene. Recovered individuals have reached up to 3.81–4.2 metres (12.5–13.8 ft) in height, and an estimated 11.3–15 tonnes in weight. Like modern elephants, the straight-tusked elephant lived in herds, flourishing during interglacial periods, when its range would extend as far north as Great Britain. Skeletons found in association with stone tools and wooden spears suggest they were scavenged and hunted by early humans, including Neanderthals. It is the ancestral species of most dwarf elephants that inhabited islands in the Mediterranean.
Syndyoceras is a small extinct genus of Artiodactyla, of the family Protoceratidae, endemic to central North America from the Miocene epoch, existing for approximately 4.2 million years.
The woolly mammoth is an extinct species of mammoth that lived during the Pleistocene until its extinction in the Holocene epoch. It was one of the last in a line of mammoth species, beginning with the African Mammuthus subplanifrons in the early Pliocene. The woolly mammoth began to diverge from the steppe mammoth about 800,000 years ago in East Asia. Its closest extant relative is the Asian elephant. The Columbian mammoth lived alongside the woolly mammoth in North America, and DNA studies show that the two hybridised with each other.
Primelephas is a genus of Elephantinae that existed during the Miocene and Pliocene epochs. The name of the genus suggests 'first elephant'. These primitive elephantids are thought to be the common ancestor of Mammuthus, the mammoths, and the closely allied genera Elephas and Loxodonta, the Asian and African elephants, diverging some 4-6 million years ago. It had four tusks, which is a trait not shared with its descendants, but common in earlier proboscideans. The type species, Primelephas gomphotheroides, was described by Vincent Maglio in 1970, with the specific epithet indicating the fossil specimens were gomphothere-like. Primelephas korotorensis is the only other species to be assigned to the genus. All fossils found of the Primelephas have been found in Africa, primarily in modern day Chad, Tanzania, Kenya, Ethiopia, and Uganda.
Rhynchotherium is an extinct genus of proboscidea endemic to North America and Central America during the Miocene through Pliocene from 13.650 to 3.6 Ma, living for approximately 10 million years.
Elephantoidea is a taxonomic group that contains the elephants as well as their closest extinct relatives. An autapomorphic feature of the group is the presence of a checkerboard pattern formed by dentinal tubules. The following cladogram shows the relationships among elephantoids, based on hyoid characteristics:
Elephantida is a group that contains the elephants as well as their extinct relatives, the gomphotheres, choerolophodontids, amebelodontids and the stegodontids. The following cladogram shows the relationships among elephantidans, based on hyoid characteristics:
Elephantimorpha is a group that contains the Mammutidae (mastodons), as well as Elephantida. All members of this group have the horizontal tooth replacement typical of modern elephants.