Mammutidae | |
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Mounted Mammut skeleton, Museum of the Earth | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Proboscidea |
Clade: | Elephantimorpha |
Clade: | † Mammutida |
Superfamily: | † Mammutoidea Hay, 1922 [2] |
Family: | † Mammutidae Hay, 1922 |
Genera [3] | |
† Eozygodon Tassy and Pickford, 1983 Contents | |
Synonyms | |
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Mammutidae is an extinct family of proboscideans belonging to Elephantimorpha. It is best known for the mastodons (genus Mammut), which inhabited North America from the Late Miocene until their extinction at 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.
Mammutids are characterised by their zygodont molars, where pairs of parallel cusps are merged into sharp-sided riges, which are morphologically conservative (showing little variation) amongst all members of the family. [6] Like other members of Elephantimorpha, mammutids exhibited horizontal tooth replacement like modern elephants. Some authors have argued that horizontal tooth replacement evolved in parallel in mammutids and members of Elephantida (which includes gomphotheres and elephants), though this is uncertain. [7] Early members of the group like Eozygodon and Zygolophodon had elongate mandibular symphysis of the lower jaws with lower incisors/tusks, while in later representatives like Sinomammut and Mammut , the lower incisors/tusks were either lost or only vestigially present, and the lower jaws shortened (brevirostrine). This process happened convergently amongst other elephantimorph proboscideans, including gomphotheres, stegodontids, and elephantids. [8] [9] The mammutid "Mammut" borsoni is one of the largest of all proboscideans with an estimated average male body weight of 16 tonnes (35,000 lb) making it one of the largest land mammals of all time, [10] with the tusks of this species being the longest known of any mammal, reaching over 5 metres (16 ft) in length. [11]
Members of Mammutidae are thought to have been browsers. [12] [13] [14] Analysis of American mastodon (Mammut americanum) remains suggests that mammutids had a similar social structure to modern elephants, with herds of adult females and juveniles, with adult males living solitarily or in bonding groups with other males, [15] [16] with adult males periodically engaging in musth-like fighting behaviour against other males. [15]
Mammutids are the most basal group within Elephantimorpha, with gomphotheres and other members of Elephantida like amebelodonts being more closely related to elephants. [17] [18] Mammutids originated in Africa during the Late Oligocene, with the oldest genus Losodokodon dating to around 27.5-24 million years ago [19] and entered Eurasia across the " Gomphotherium land bridge" during the early Miocene, around 18 million years ago. Mammutid remains are generally rare in Eurasia in comparison to contemporary gomphotheres and deinotheres. [6] During the late early Miocene, around 16.5 million years ago, [20] a population of Zygolophodon entered North America, giving rise to Mammut. [6] The youngest confirmed records of mammutids in Africa date to around 13 million years ago, though possible Late Miocene fossils have been reported from North Africa. [21] At the beginning of the Pleistocene, around 2 to 2.5 million years ago, the last of the Eurasian mammutids, "Mammut" borsoni became extinct, with members of Mammut persisting in North America until the end of the Pleistocene, approximately 11,000 years ago. [6]
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 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, strictly defined, 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.
Gomphotheres are an extinct group of proboscideans related to modern elephants. They were widespread across Afro-Eurasia and North America during the Miocene and Pliocene epochs and dispersed into South America during the Pleistocene as part of the Great American Interchange. Gomphotheres are a paraphyletic group that is ancestral to Elephantidae, which contains modern elephants, as well as Stegodontidae. While most famous forms such as Gomphotherium had long lower jaws with tusks, which is the ancestral condition for the group, some later members developed shortened (brevirostrine) lower jaws with either vestigial or no lower tusks, looking very similar to modern elephants, an example of parallel evolution, which outlasted the long-jawed gomphotheres. By the end of the Early Pleistocene, gomphotheres became extinct in Afro-Eurasia, with the last two genera, Cuvieronius ranging from southern North America to western South America, and Notiomastodon having a wide range over most of South America until the end of the Pleistocene around 12,000 years ago, when they became extinct following the arrival of humans.
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.
Cuvieronius is an extinct New World genus of gomphothere which ranged from southern North America to western South America during the Pleistocene epoch. Among the last gomphotheres, it became extinct at the end of the Pleistocene, approximately 12,000 years ago, following the arrival of humans to the Americas.
Stegomastodon is an extinct genus of gomphotheres. It ranged throughout North America from the Pliocene, to the Early Pleistocene. The former South American species have been synonymized with Notiomastodon platensis.
Sinomastodon is an extinct gomphothere genus known from the Late Miocene to Early Pleistocene of Asia, including China, Japan, Thailand, Myanmar, Indonesia and probably Kashmir.
Tetralophodon is an extinct genus of "tetralophodont gomphothere" belonging to the superfamily Elephantoidea, known from the Miocene of Afro-Eurasia.
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.
Gnathabelodon is an extinct genus of gomphothere endemic to North America that includes species that lived during the Middle to Late Miocene.
Eubelodon is an extinct genus of gomphothere which lived in North America during the Miocene Epoch. It contains a single species: Eubelodon morrilli.
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.
Choerolophodon is an extinct genus of proboscidean that lived during the Miocene of Eurasia and Africa. Fossils of Choerolophodon have been found in Africa, Southeast Europe, Turkey, Iraq, Iran, the Indian subcontinent, and China.
Elephantimorpha is a clade of proboscideans that contains the Mammutidae (mastodons), as well as Elephantida. All members of this group have the horizontal tooth replacement typical of modern elephants, unlike more primitive members of the Elephantiformes. Like modern elephants, the ancestor of Elephantimorpha was likely capable of communicating via infrasonic calls. While early elephantimorphs generally had lower jaws with an elongated mandibular symphysis at the front of the jaw with well developed lower tusks/incisors, from the Late Miocene onwards, many groups convergently developed brevirostrine (shortened) lower jaws with vestigial or no lower tusks, probably corresponding with the elongation and increasingly dexterity of the trunk allowing it to be used as the primary feeding organ.
Sinomammut is a mammutid proboscidean from the Miocene of China. Only one species, S. tobieni, is known, named in 2016.
Amebelodontidae is an extinct family of large herbivorous proboscidean mammals related to elephants. They were formerly assigned to Gomphotheriidae, but recent authors consider them a distinct family. They are distinguished from other proboscideans by having flattened lower tusks and very elongate mandibular symphysis. The lower tusks could grow to considerable size, with those of Konobelodon reaching 1.61 metres (5.3 ft) in length. Their molar teeth are typically trilophodont, and possessed posttrite conules. In the past, amebelodonts' shovel-like mandibular tusks led to them being portrayed scooping up water plants, however, dental microwear suggests that they were browsers and mixed feeders. The lower tusks have been proposed to have had a variety of functions depending on the species, including stripping bark, cutting through vegetation, as well as possibly digging. They first appeared in Africa during the Early Miocene, and subsequently dispersed into Eurasia and then North America. They became extinct by the beginning of the Pliocene. While some phylogenetic studies have recovered Amebelodontidae as a monophyletic group that forms the sister group to Gomphotheriidae proper, some authors have argued that Amebelodontidae may be polyphyletic, with it being suggested that the shovel-tusked condition arose several times independently within Gomphotheriidae, thus rendering the family invalid.
Eozygodon is an extinct genus of proboscidean in the family Mammutidae that is based on a single species, E. morotoensis, named in 1983. It is known from the Early Miocene of Africa and well as possibly the Middle Miocene of China. It is considered a primitive member of the family, retaining a long lower jaw (longirostrine) with lower tusks. The upper tusks are small, and are parallel to each other. The skull of the young adult AM 02 from Auchas, Namibia, was around the size of that of a 10 year old American mastodon, around 60 centimetres (2.0 ft) in maximum length. Dental mesowear from East African specimens suggests a browsing diet. Some authors suggest that Eozygodon could be less closely related to other members of Mammutidae than other mammutids are to Elephantida, making Mammutidae as typically defined paraphyletic.
"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.