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Toothcomb - Jones 1918
A toothcomb (also tooth comb or dental comb) is a dental structure found in some mammals, comprising a group of front teeth arranged in a manner that facilitates grooming, similar to a hair comb. The toothcomb occurs in lemuriform primates (which includes lemurs and lorisoids), treeshrews, colugos, hyraxes, and some African antelopes. The structures evolved independently in different types of mammals through convergent evolution and varies both in dental composition and structure. In most mammals the comb is formed by a group of teeth with fine spaces between them. The toothcombs in most mammals include incisors only, while in lemuriform primates they include incisors and canine teeth that tilt forward at the front of the lower jaw, followed by a canine-shaped first premolar. The toothcombs of colugos and hyraxes take a different form with the individual incisors being serrated, providing multiple tines per tooth. The toothcomb is usually used for grooming. While licking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Toothcomb - Jones 1918
A toothcomb (also tooth comb or dental comb) is a dental structure found in some mammals, comprising a group of front teeth arranged in a manner that facilitates grooming, similar to a hair comb. The toothcomb occurs in lemuriform primates (which includes lemurs and lorisoids), treeshrews, colugos, hyraxes, and some African antelopes. The structures evolved independently in different types of mammals through convergent evolution and varies both in dental composition and structure. In most mammals the comb is formed by a group of teeth with fine spaces between them. The toothcombs in most mammals include incisors only, while in lemuriform primates they include incisors and canine teeth that tilt forward at the front of the lower jaw, followed by a canine-shaped first premolar. The toothcombs of colugos and hyraxes take a different form with the individual incisors being serrated, providing multiple tines per tooth. The toothcomb is usually used for grooming. While licking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Djebelemur
''Djebelemur'' is an extinct genus of early strepsirrhine primate from the late early or early middle Eocene period from the Chambi locality in Tunisia. Although they probably lacked a toothcomb, a specialized dental structure found in living lemuriforms (lemurs and lorisoids), they are thought to be a related stem group. The one recognized species, ''Djebelemur martinezi'', was very small, approximately . ''Djebelemur'' is one of five genera of djebelemurids, others including '' 'Anchomomys' milleri'', a fossil primate formerly thought to be related to other members of the genus '' Anchomomys'', a group of Eocene European adapiform primates. Following its discovery and description in 1992, ''Djebelemur'' was thought to be either a relative of European adapiforms or an early simian, mostly due to the fragmentary nature of the lower jaw and two isolated upper molars that may not belong with the jaw. By 2006, it was viewed as a stem lemuriform. Etymology The name "''Djebe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cercamoniinae
Cercamoniinae is a subfamily within the extinct primate family Notharctidae primarily found in Europe, although a few genera have been found in North America and Africa. Classification *Family Notharctidae Notharctidae is an extinct family of adapiform primate Primates are a diverse order of mammals. They are divided into the strepsirrhines, which include the lemurs, galagos, and lorisids, and the haplorhines, which include the tarsiers an ... **Subfamily Cercamoniinae ***Genus '' Agerinia'' ***Genus '' Anchomomys'' ***Genus '' Barnesia'' ***Genus '' Buxella'' ***Genus '' Donrussellia'' ***Genus '' Mazateronodon'' ***Genus '' Panobius'' ***Genus '' Periconodon'' ***Genus '' Pronycticebus'' ***Genus '' Protoadapis'' References Literature cited * External linksMikko's Phylogeny Archive {{Taxonbar, from=Q842001 Prehistoric strepsirrhines Eocene first appearances Eocene extinctions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mya (unit)
Mya may refer to: Brands and product names * Mya (program), an intelligent personal assistant created by Motorola * Mya (TV channel), an Italian Television channel * Midwest Young Artists, a comprehensive youth music program Codes * Burmese language, ISO 639-3 code is * Moruya Airport's IATA code * The IOC, license plate, and UNDP country code for Myanmar ("MYA") People * Mya (given name) * Mya (singer) (Mya Marie Harrison, born 1979), an American R&B singer-songwriter and actress * Bo Mya (1927–2006), nom de guerre of a Myanmar rebel leader, chief rapist of the Karen National Union Other uses * ''Mýa'' (album), a 1998 album by Mýa * ''Mya'' (bivalve), a genus of soft-shell clams * MYA (unit) for "million years ago", a science-related unit of time used in astronomy, geology and biology See also * A (motor yacht) (M/Y A), a superyacht * Maia (other) * Maya (other) Maya may refer to: Civilizations * Maya peoples, of southern Mexico and norther ... [...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 Chicxulub impact, an asteroid impact and possibly volcanism, marked the beginning of the Paleocene and killed off 75% of living 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. In the Pal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adapidae
Adapidae is a family of extinct primates that primarily radiated during the Eocene epoch between about 55 and 34 million years ago. Adapid systematics and evolutionary relationships are controversial, but there is fairly good evidence from the postcranial skeleton (everything but the skull, or cranium) that adapids were stem strepsirrhines (members of the group including the living lemurs, lorises, and bushbabies). In particular, the anatomy of the adapid wrist and ankle (e.g., position of the groove for the flexor fibularis tendon on the talus, the presence of a sloping talo-fibular facet) show derived similarities with those of living strepsirrhines. However, adapids lacked many of the anatomical specializations characteristic of living strepsirrhines, such as a toothcomb,Rose, K. D., A. Walker, and L. L. Jacobs. 1981. Function of the mandibular tooth comb in living and extinct mammals. Nature 289:583-585. a toilet-claw A grooming claw (or toilet claw) is the specialized cla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "dawn") and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch. The Eocene spans the time from the end of the Paleocene Epoch to the beginning of the Oligocene Epoch. The start of the Eocene is marked by a brief period in which the concentration of the carbon isotope Carbon-13, 13C in the atmosphere was exceptionally low in comparison with the more common isotope Carbon-12, 12C. The end is set at a major extinction event called the ''Grande Coupure'' (the "Great Break" in continuity) or the Eocene–Oligocene extinction event, which may be related to the impact of one or more large bolides in Popigai impact structure, Siberia and in what is now ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adapiformes
Adapiformes is a group of early primates. Adapiforms radiated throughout much of the northern continental mass (now Europe, Asia and North America), reaching as far south as northern Africa and tropical Asia. They existed from the Eocene to the Miocene epoch. Some adapiforms resembled living lemurs. Adapiforms are known from the fossil record only, and it is unclear whether they form a monophyletic or paraphyletic group. When assumed to be a clade, they are usually grouped under the "wet-nosed" taxon Strepsirrhini, which would make them more closely related to the lemurs and less so to the "dry-nosed" Haplorhini taxon that includes monkeys and apes.Callum Ross, Richard F. Kay, ''Anthropoid origins: new visions'', Springer, 2004, , p. 100 In 2009, Franzen and colleagues placed the newly described genus ''Darwinius'' in the "Adapoidea group of early primates representative of early haplorhine diversification" so that, according to these authors, the adapiforms would not be within ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary History Of Lemurs
Lemurs, primates belonging to the suborder Strepsirrhini which branched off from other primates less than 63 million years ago, evolved on the island of Madagascar, for at least 40 million years. They share some traits with the most basal primates, and thus are often confused as being ancestral to modern monkeys, apes, and humans. Instead, they merely resemble ancestral primates. Lemurs are thought to have evolved during the Eocene or earlier, sharing a closest common ancestor with lorises, pottos, and galagos (lorisoids). Fossils from Africa and some tests of nuclear DNA suggest that lemurs made their way to Madagascar between 40 and 52 mya. Other mitochondrial and nuclear DNA sequence comparisons offer an alternative date range of 62 to 65 mya. An ancestral lemur population is thought to have inadvertently rafted to the island on a floating mat of vegetation, although hypotheses for land bridges and island hopping have also been proposed. The timing and numb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aye-aye
The aye-aye (''Daubentonia madagascariensis'') is a long-fingered lemur, a strepsirrhine primate native to Madagascar with rodent-like teeth that perpetually grow and a special thin middle finger. It is the world's largest nocturnal primate. It is characterized by its unusual method of finding food: it taps on trees to find grubs, then gnaws holes in the wood using its forward-slanting incisors to create a small hole into which it inserts its narrow middle finger to pull the grubs out. This foraging method is called ''percussive foraging'', and takes up 5–41% of foraging time. The only other animal species known to find food in this way is the striped possum. From an ecological point of view, the aye-aye fills the niche of a woodpecker, as it is capable of penetrating wood to extract the invertebrates within. The aye-aye is the only extant member of the genus ''Daubentonia'' and family Daubentoniidae. It is currently classified as Endangered by the IUCN. A second species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
