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Stegodon
''Stegodon'' (from the Ancient Greek στέγω (''stégō''), meaning "to cover", and ὀδούς (''odoús''), meaning "tooth", named for the distinctive ridges on the animal's molars) is an extinct genus of proboscidean, related to elephants. It was originally assigned to the family Elephantidae along with modern elephants but is now placed in the extinct family Stegodontidae. Like elephants, ''Stegodon'' had teeth with plate-like lophs that are different from those of more primitive proboscideans like gomphotheres and mammutids. Fossils of the genus are known from Africa and across much of Asia, as far southeast as Timor (with a single record in southeast Europe). The oldest fossils of the genus are found in Late Miocene strata in Asia, likely originating from the more archaic ''Stegolophodon,'' subsequently migrating into Africa. While the genus became extinct in Africa during the Pliocene, ''Stegodon'' persisted in South, Southeast and Eastern Asia into the Late Pleisto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegodon Aurorae
''Stegodon aurorae'' is an extinct species of ''Stegodon'' known from Early Pleistocene (2.0 Ma – 1.0 Ma) of Japan and possibly Taiwan. It appears to be an insular dwarf species, exhibiting smaller body size than its mainland ancestors. Description The best-preserved ''Stegodon aurorae'' skeleton, that from Taga in Shiga Prefecture, stands to a shoulder height of , with a body length of . It is relatively short-legged, the ratio between vertebral column length and shoulder height being 0.88. The body mass of ''S. aurorae'' has been calculated at one quarter (around ) of that of its mainland ancestor ''S. zdanskyi'', which had a shoulder height of around ; as such, it is an example of insular dwarfism. Distribution Remains of ''Stegodon aurorae'' have been found in over forty-five localities in the Japanese archipelago, mainly in central Honshū. The Type (biology)#Type specimen, type specimen was from Ishikawa Prefecture, while among the eight skeletons, one was found in Sait ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Insular Dwarfism
Insular dwarfism, a form of phyletic dwarfism, is the process and condition of large animals evolving or having a reduced body size when their population's range is limited to a small environment, primarily islands. This natural process is distinct from the intentional creation of dwarf breeds, called dwarfing. This process has occurred many times throughout evolutionary history, with examples including various species of Dwarf elephant, dwarf elephants that evolved during the Pleistocene epoch, as well as more ancient examples, such as the dinosaurs ''Europasaurus'' and ''Magyarosaurus''. This process, and other "island genetics" artifacts, can occur not only on islands, but also in other situations where an ecosystem is isolated from external resources and breeding. This can include caves, desert oases, isolated valleys and isolated mountains ("sky islands"). Insular dwarfism is one aspect of the more general Foster's rule, "island effect" or "Foster's rule", which posits that w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegodon Skeletal
''Stegodon'' (from the Ancient Greek στέγω (''stégō''), meaning "to cover", and ὀδούς (''odoús''), meaning "tooth", named for the distinctive ridges on the animal's molars) is an extinct genus of proboscidean, related to elephants. It was originally assigned to the family Elephantidae along with modern elephants but is now placed in the extinct family Stegodontidae. Like elephants, ''Stegodon'' had teeth with plate-like lophs that are different from those of more primitive proboscideans like gomphotheres and mammutids. Fossils of the genus are known from Africa and across much of Asia, as far southeast as Timor (with a single record in southeast Europe). The oldest fossils of the genus are found in Late Miocene strata in Asia, likely originating from the more archaic ''Stegolophodon,'' subsequently migrating into Africa. While the genus became extinct in Africa during the Pliocene, ''Stegodon'' persisted in South, Southeast and Eastern Asia into the Late Pleistoc ... [...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] |
Elephantimorpha
Elephantimorpha is a clade of proboscideans that contains the Mammutidae (mastodons), as well as Elephantida ( amebelodonts, choerolophodonts, gomphotheres, stegodontids and elephantids). All members of Elephantimorpha have the horizontal tooth replacement typical of modern elephants, where the cheek teeth progressively migrate forwards in the jaw like a conveyor belt. This a distinctive characteristic of this group (synapomorphy) and is not found in more primitive non-elephantimorph Elephantiformes. Members of Elephantida are distinguished from mammutids by the reduced angular process of the lower jaw. Like modern elephants, the ancestor of Elephantimorpha was likely capable of communicating via infrasonic calls. While early elephantimorphs generally had lower jaws where the fused front part (the mandibular symphysis) was greatly elongated with well developed lower tusks/incisors, from the Late Miocene onwards, many groups convergently developed brevirostrine (shortened) lowe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegolophodon
''Stegolophodon'' is an extinct genus of Stegodontidae, stegodontid proboscideans. It lived during the Miocene epoch in Asia. The earliest fossils are known from the Early Miocene, with one of the oldest fossils being from Japan, estimated to be 17.3 million years old. It is suggested to be the ancestor of ''Stegodon'', and transitional fossils between the two genera known from the Late Miocene of Southeast Asia and Yunnan in South China. Like modern elephants, ''Stegolophodon'' developed proal jaw movement, where the lower jaw moves in a back-to-front motion, rather than the oblique chewing motion used by earlier proboscideans, with this development already present by 17.3 million years ago. Members of the genus generally have tetralophodont molars, and retain tusks on the lower jaw. The upper tusks have an enamel band. References Stegodontidae Miocene proboscideans Pliocene proboscideans Prehistoric placental genera Neogene mammals of Asia Fossil taxa described in 191 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timor
Timor (, , ) is an island at the southern end of Maritime Southeast Asia, in the north of the Timor Sea. The island is Indonesia–Timor-Leste border, divided between the sovereign states of Timor-Leste in the eastern part and Indonesia in the western part. The Indonesian part, known as West Timor, constitutes part of the Provinces of Indonesia, province of East Nusa Tenggara. Within West Timor lies an exclave of Timor-Leste called Oecusse District. The island covers an area of . The name is a variant of ''timur'', Malay language, Malay for "east"; it is so called because it lies at the eastern end of the Lesser Sunda Islands. Mainland Australia is less than 500 km away, separated by the Timor Sea. Language, ethnic groups and religion Anthropologists identify eleven distinct Ethnolinguistic group, ethno-linguistic groups in Timor. The largest are the Atoni of western Timor and the Tetum language, Tetum of central and eastern Timor. Most indigenous Timorese languages ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammutidae
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 (around 8 million years ago) 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, "nipple" and "tooth", referring to their characteristic teeth. Description Mammutids are characterised by their zygodont molars, where pairs of parallel cusps are merged into sharp-sided riges, which are morphologically conservative and differ little between mammutid species.'''' 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 mammu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gomphotheres
Gomphotheres are an extinct group of proboscideans related to modern Elephant, 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 Paraphyly, paraphyletic group ancestral to Elephantidae, which contains modern elephants, as well as Stegodontidae. While most famous forms such as ''Gomphotherium'' had long lower jaws with tusks, the Plesiomorphy and symplesiomorphy, ancestral condition for the group, some later members developed shortened (brevirostrine) lower jaws with either vestigial or no lower tusks and outlasted the long-jawed gomphotheres. This change made them look very similar to modern elephants, an example of parallel evolution. During the Pliocene and Early Pleistocene, the diversity of gomphotheres declined, ultimately becoming extinct outside of the Americas. The last two genera, ''Cuv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58See the 2014 version of the ICS geologic time scale million years ago (Ma). It is the second and most recent epoch of the Neogene Period in the Cenozoic, Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch. Prior to the 2009 revision of the geologic time scale, which placed the four most recent major glaciations entirely within the Pleistocene, the Pliocene also included the Gelasian Stage, which lasted from 2.59 to 1.81 Ma, and is now included in the Pleistocene. As with other older geologic periods, the Stratum, geological strata that define the start and end are well-identified but the exact dates of the start a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephant
Elephants are the largest living land animals. Three living species are currently recognised: the African bush elephant ('' Loxodonta africana''), the African forest elephant (''L. cyclotis''), and the Asian elephant ('' Elephas maximus''). 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. Elephants are scatter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stegodontidae
Stegodontidae is an extinct family of proboscideans from Africa and Asia (with a single occurrence in Europe) from the Early Miocene (at least 17.3 million years ago) to the Late Pleistocene. It contains two genera, the earlier ''Stegolophodon'', known from the Miocene of Asia and the later '' Stegodon,'' from the Late Miocene to Late Pleistocene of Africa and Asia (with a single occurrence in Greece) which is thought to have evolved from the former. The group is noted for their plate-like lophs on their teeth, which are similar to elephants and different from those of other extinct proboscideans like gomphotheres Gomphotheres are an extinct group of proboscideans related to modern Elephant, 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 Ple ... and mammutids, with both groups having a proal jaw movement utilizing forward strokes of the lower jaw. These simila ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
