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Paenungulatomorpha
Paenungulatomorpha is a clade of Afrotheria, afrotherian mammals that can be characterized according to Gheerbrant et al. (2016):''by a mandibular retromolar fossa, the absence of hypocone, an ectoloph selenodont and linked to strong styles such as mesostyle in basal taxa, and a more or less developed pseudohypocone.'' Originally it was thought Paenungulata, paenungulates were closely related to the Perissodactyla, perissodactyls in the clade Altungulata due to shared attributes in the dental, osteological and soft-tissues. However this view was contested as molecular studies have widely supported that paenungulates are not related to the perissodactyls, instead more related to the widely different clade Afroinsectiphilia, with them forming the clade Afrotheria. There has been also some morphological data to support Afrotheria, though the paleontological record to support was lacking until reexamination of the genera ''Ocepeia'' and ''Abdounodus'', as well as the description of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hadrogeneios
''Hadrogeneios'' is an extinct genus of afrotherian mammal recovered from the Khouribga Phosphates of the Ouled Abdoun Basin dating from the Selandian to the Thanetian. Only the type species ''H. phosphaticus'' is known for this genus, with the material being of dental and jaw specimens. The placement of ''Hadrogeneios'' recovered it to be the most basal stem-Paenungulata, paenungulate, the clade that includes elephants, Sirenia, sea cows, and hyraxes. Despite this ''Hadrogeneios'' was a contemporary of more derived members of the group such as ''Abdounodus'', ''Ocepeia'', and the early proboscideans ''Eritherium'', ''Phosphatherium'', and ''Daouitherium''. Discovery and naming The known material of ''Hadrogeneios'' were collected from the local people from an unknown site in Ouled Abdoun Basin, though it is inferred they come from the Sidi Chennane quarry. Geochemical studies of the Paleocene mammals show phosphate intervals which suggested the bed of which ''Hadrogeneios'' ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abdounodus
''Abdounodus'' ("Abdoun tooth") is an extinct genus of mammal known from the middle Paleocene of Northern Africa. The sole species, ''A. hamdii'', is known from teeth and jaw bones discovered in the Ouled Abdoun Basin The Oulad Abdoun Basin (also known as the Ouled Abdoun Basin or Khouribga Basin) is a phosphate sedimentary basin located in Morocco, near the city of Khouribga. It is the largest in Morocco, comprising 44% of Morocco's phosphate reserves, and at ... of present-day Morocco in 2001. Discovery and naming Discovery The holotype of Abdounodus hamdii MNHN 21 was collected in French fossil markets. It consists of a left mandible and teeth. A study in 2016 described new material that included the maxillary and upper dentition. Naming The generic name combines Abdoun referring to the place of origin and odus meaning tooth. The specific name hamdii is named after M. Mohamed Hamdi, who was an active supporter for paleontological research in the region. Description A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ocepeia
''Ocepeia'' is an extinct genus of afrotherian mammal that lived in present-day Morocco during the middle Paleocene epoch, approximately 60 million years ago. First named and described in 2001, the type species is ''O. daouiensis'' from the Selandian stage of Morocco's Ouled Abdoun Basin. A second, larger species, ''O. grandis'', is known from the Thanetian, a slightly younger stage in the same area. In life, the two species are estimated to have weighed about and , respectively, and are believed to have been specialized leaf-eaters. The fossil skulls of ''Ocepeia'' are the oldest known afrotherian skulls, and the best-known of any Paleocene mammal in Africa. ''Ocepeia'' was initially grouped with the archaic ungulates known as "condylarths", but ''Ocepeia'' shares several features with primitive paenungulates (a group including elephants, hyraxes, sea cows and extinct relatives), but some analyses suggest it is more closely related to Afroinsectiphilia (a group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paenungulata
Paenungulata (from Latin ''paene'' "almost" + ''ungulātus'' "having hoofs") is a clade of "sub- ungulates", which groups three extant mammal orders: Proboscidea (including elephants), Sirenia ( sea cows, including dugongs and manatees), and Hyracoidea ( hyraxes). At least two more possible orders are known only as fossils, namely Embrithopoda and Desmostylia. Molecular evidence indicates that Paenungulata (or at least its extant members) is part of the cohort Afrotheria, an ancient assemblage of mainly African mammals of great diversity. The other members of this cohort are the orders Afrosoricida ( tenrecs and golden moles), Macroscelidea ( elephant shrews) and Tubulidentata ( aardvarks). Of the five orders, hyraxes are the most basal, followed by embrithopods; the remaining orders (sirenians and elephants) are more closely related. These latter three are grouped as the Tethytheria, because it is believed that their common ancestors lived on the shores of the prehisto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Afrotheria
Afrotheria ( from Latin ''Afro-'' "of Africa" + ''theria'' "wild beast") is a superorder of placental mammals, the living members of which belong to groups that are either currently living in Africa or of African origin: golden moles, elephant shrews (also known as sengis), otter shrews, tenrecs, aardvarks, hyraxes, elephants, sea cows, and several extinct clades. Most groups of afrotheres share little or no superficial resemblance, and their similarities have only become known in recent times due to genetics and molecular studies. Many afrothere groups are found mostly or exclusively in Africa, reflecting the fact that Africa was an island continent from the Cretaceous until the early Miocene around 20 million years ago, when Afro-Arabia collided with Eurasia. Because Africa was isolated by water, Laurasian groups of mammals such as insectivores, rodents, lagomorphs, carnivorans and ungulates could not reach Africa for much of the early to mid-Cenozoic. Instead, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyracoidea
Hyraxes (), also called dassies, are small, stout, thickset, herbivorous mammals in the family (biology), family Procaviidae within the Order (biology), order Hyracoidea. Hyraxes are well-furred, rotund animals with short tails. Modern hyraxes are typically between in length and weigh between . They are superficially similar to marmots or over-large pikas but are much more closely related to elephants and sirenians. Hyraxes have a life span of 9 to 14 years. Both types of "rock" hyrax (rock hyrax, ''P. capensis'' and yellow-spotted rock hyrax, ''H. brucei'') live on rock outcrops, including cliffs in Ethiopia and isolated granite outcrops called Inselberg, koppies in southern Africa. Almost all hyraxes are limited to Africa; the exception is the rock hyrax (''P. capensis'') which is also found in adjacent parts of the Middle East. Hyraxes were a much more diverse group in the past encompassing species considerably larger than modern hyraxes. The largest kno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proboscidea
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. Extinct members of Proboscidea include the deinotheres, mastodons, gomphotheres and stegodonts. The family Elephantidae also contains several extinct groups, including mammoths and '' Palaeoloxodon''. Proboscideans include some of the largest known land mammals, with the elephant '' Palaeoloxodon namadicus'' and mastodon ''"Mammut" borsoni'' suggested to have body masses surpassing , rivalling or exceeding paraceratheres (the otherwise largest known land mammals) in size. The largest extant proboscidean is the African bush elephant, with a world record of size of at the shoulder and . In addition to thei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sirenia
The Sirenia (), commonly referred to as sea cows or sirenians, are an order of fully aquatic, herbivorous mammals that inhabit swamps, rivers, estuaries, marine wetlands, and coastal marine waters. The extant Sirenia comprise two distinct families: Dugongidae (the dugong and the now extinct Steller's sea cow) and Trichechidae (manatees, namely the Amazonian manatee, West Indian manatee, and West African manatee) with a total of four species. The Protosirenidae (Eocene sirenians) and Prorastomidae (terrestrial sirenians) families are extinct. Sirenians are classified in the clade Paenungulata, alongside the elephants and the hyraxes, and evolved in the Eocene 50 million years ago (mya). The Dugongidae diverged from the Trichechidae in the late Eocene or early Oligocene (30–35 mya). Sirenians grow to between in length and in weight. The recently extinct Steller's sea cow was the largest known sirenian to have lived, reaching lengths of and weights of . Sirenians have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tethytheria
Tethytheria is a clade of mammals that includes the sirenians, proboscideans, and the extinct order Embrithopoda. Though there is strong anatomical and molecular support for the monophyly of Tethytheria, the interrelationships between the included taxa remain disputed. The tethytheres are united by several characters, including anteriorly facing orbits In celestial mechanics, an orbit (also known as orbital revolution) is the curved trajectory of an physical body, object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an satellite, artificia ... and more or less bilophodont cheek teeth (double transverse ridges on the crowns of the teeth). Proboscidea and Sirenia are linked together based on auditory characters in their petrosal bones, but this link may be a homoplasy. Desmostylians, traditionally considered tethytheres, have been tentatively assigned to Perissodactyla, along with the Early Eocene family Anthracob ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embrithopoda
Embrithopoda ("heavy-footed") is an Order (biology), order of extinct mammals known from Asia, Africa and Eastern Europe. Most of the embrithopod genera are known exclusively from jaws and teeth dated from the late Paleocene to the late Eocene; however, the order is best known from its terminal member, the elephantine ''Arsinoitherium''. Description While embrithopods bore a superficial resemblance to rhinoceroses, their horns had bony cores covered in keratinized skin. Not all embrithopods possessed horns, either. Despite their appearance, they have been regarded as related to elephants, not perissodactyls. As Tethytheria, tethytheres, the Embrithopoda have been believed to be part of the clade Afrotheria. However, a study of the basal arsinoitheriid, ''Palaeoamasia'', suggests that embrithopods are not Tethytheria, tethytheres or even Paenungulata, paenungulates, and that they need to be better sampled in an analysis of eutherian relationships to clarify if they are even afrot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleocene
The Paleocene ( ), or Palaeocene, is a geological epoch (geology), epoch that lasted from about 66 to 56 mya (unit), million years ago (mya). It is the first epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name is a combination of the Ancient Greek ''palaiós'' meaning "old" and the Eocene Epoch (which succeeds the Paleocene), translating to "the old part of the Eocene". The epoch is bracketed by two major events in Earth's history. The K–Pg extinction event, brought on by an asteroid impact (Chicxulub impact) and possibly volcanism (Deccan Traps), marked the beginning of the Paleocene and killed off 75% of species, most famously the non-avian dinosaurs. The end of the epoch was marked by the Paleocene–Eocene Thermal Maximum (PETM), which was a major climatic event wherein about 2,500–4,500 gigatons of carbon were released into the atmosphere and ocean systems, causing a spike in global temperatures and ocean acidification. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
