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Apeomyoides
''Apeomyoides savagei'' is a fossil rodent from the Miocene of the United States, the only species in the genus ''Apeomyoides''. It is known from fragmentary jaws and isolated teeth from a site in the early Barstovian, around 15–16 million years ago, of Nevada. Together with other species from scattered localities in the United States, Japan, and Europe, ''Apeomyoides'' is classified in the subfamily Apeomyinae of the extinct rodent family Eomyidae. Apeomyines are a rare but widespread group that may have been adapted to a relatively dry habitat. As is characteristic of apeomyines, ''Apeomyoides'' was a large eomyid with high-crowned cheekteeth and a large gap between the incisors and cheekteeth. Furthermore, the cheekteeth—premolars and molars—approach a bilophodont pattern, with two distinct lobes. Other features distinguish ''Apeomyoides'' from other apeomyines, including the rectangular shape of the cheekteeth. The fourth lower premolar (p4) is larger than the molars b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eomyidae
Eomyidae is a family of extinct rodents from North America and Eurasia related to modern day pocket gophers and kangaroo rats. They are known from the Middle Eocene to the Late Miocene in North America and from the Late Eocene to the Pleistocene in Eurasia. Eomyids were generally small, but occasionally large, and tended to be squirrel-like in form and habits. The family includes the earliest known gliding rodent, '' Eomys quercyi''. The family includes the following genera: *'' Simiacritomys'' (placement uncertain) *'' Symplokeomys'' *Subfamily Yoderimyinae **'' Litoyoderimys'' **'' Yoderimys'' **'' Zaisaneomys'' **'' Zemiodontomys'' *Subfamily Apeomyinae **''Apeomyoides'' **'' Apeomys'' **'' Arikareeomys'' **'' Megapeomys'' **'' Zophoapeomys'' *Subfamily Eomyinae **'' Adjidaumo'' **'' Aguafriamys'' **'' Asianeomys'' **'' Aulolithomys'' **'' Centimanomys'' **'' Comancheomys'' **'' Cristadjidaumo'' **'' Cupressimus'' **'' Eomyodon'' **'' Eomyops'' **''Eomys ''Eomys'' is an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereopair
Stereoscopy (also called stereoscopics, or stereo imaging) is a technique for creating or enhancing the illusion of depth in an image by means of stereopsis for binocular vision. The word ''stereoscopy'' derives . Any stereoscopic image is called a stereogram. Originally, stereogram referred to a pair of stereo images which could be viewed using a stereoscope. Most stereoscopic methods present a pair of two-dimensional images to the viewer. The left image is presented to the left eye and the right image is presented to the right eye. When viewed, the human brain perceives the images as a single 3D view, giving the viewer the perception of 3D depth. However, the 3D effect lacks proper focal depth, which gives rise to the Vergence-Accommodation Conflict. Stereoscopy is distinguished from other types of 3D displays that display an image in three full dimensions, allowing the observer to increase information about the 3-dimensional objects being displayed by head and eye mov ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemingfordian
The Hemingfordian on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 20,600,000 to 16,300,000 years BP. It is usually considered to overlap the latest Aquitanian and Burdigalian of the Early Miocene. The Hemingfordian is preceded by the Arikareean and followed by the Barstovian NALMA stages. The Hemingfordian can be further divided into the substages of: *Late/Upper Hemingfordian: Lower boundary source: base of Burdigalian The Burdigalian is, in the geologic timescale, an age (geology), age or stage (stratigraphy), stage in the early Miocene. It spans the time between 20.43 ± 0.05 annum, Ma and 15.97 ± 0.05 Ma (million years ago). Preceded by the Aquitanian (sta ... (approximate). *Early/Lower Hemingfordian (shares lower boundary) References Miocene geochronology Miocene North America {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mandible (anatomy)
In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower tooth, teeth in place. The mandible sits beneath the maxilla. It is the only movable bone of the skull (discounting the ossicles of the middle ear). It is connected to the temporal bones by the temporomandibular joints. The bone is formed prenatal development, in the fetus from a fusion of the left and right mandibular prominences, and the point where these sides join, the mandibular symphysis, is still visible as a faint ridge in the midline. Like other symphyses in the body, this is a midline articulation where the bones are joined by fibrocartilage, but this articulation fuses together in early childhood.Illustrated Anatomy of the Head and Neck, Fehrenbach and Herring, Elsevier, 2012, p. 59 The word "mandible" derives from the Latin word ''mandibula'', "jawbone" (literally "one used for chewing"), from ''wikt:mandere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diastema (dentistry)
A diastema (plural diastemata, from Greek διάστημα, space) is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. More colloquially, the condition may be referred to as gap teeth or tooth gap. In humans, the term is most commonly applied to an open space between the upper incisors (front teeth). It happens when there is an unequal relationship between the size of the teeth and the jaw. Diastemata are common for children and can exist in adult teeth as well. In humans Causes 1. Oversized Labial Frenulum: Diastema is sometimes caused or exacerbated by the action of a labial frenulum (the tissue connecting the lip to the gum), causing high mucosal attachment and less attached keratinized tissue. This is more prone to recession or by tongue thrusting, which can push the teeth apart. 2. Periodontal Disease: Periodontal disease, also known as gum disease, can result in bone loss that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tooth Enamel
Tooth enamel is one of the four major Tissue (biology), tissues that make up the tooth in humans and many other animals, including some species of fish. It makes up the normally visible part of the tooth, covering the Crown (tooth), crown. The other major tissues are dentin, cementum, and Pulp (tooth), dental pulp. It is a very hard, white to off-white, highly mineralised substance that acts as a barrier to protect the tooth but can become susceptible to degradation, especially by acids from food and drink. Calcium hardens the tooth enamel. In rare circumstances enamel fails to form, leaving the underlying dentin exposed on the surface. Features Enamel is the hardest substance in the human body and contains the highest percentage of minerals (at 96%),Ross ''et al.'', p. 485 with water and organic material composing the rest.Ten Cate's Oral Histology, Nancy, Elsevier, pp. 70–94 The primary mineral is hydroxyapatite, which is a crystalline calcium phosphate. Enamel is formed o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Donald E
Donald is a masculine given name derived from the Gaelic name ''Dòmhnall''.. This comes from the Proto-Celtic *''Dumno-ualos'' ("world-ruler" or "world-wielder"). The final -''d'' in ''Donald'' is partly derived from a misinterpretation of the Gaelic pronunciation by English speakers, and partly associated with the spelling of similar-sounding Germanic names, such as ''Ronald''. A short form of ''Donald'' is ''Don''. Pet forms of ''Donald'' include ''Donnie'' and ''Donny''. The feminine given name ''Donella'' is derived from ''Donald''. ''Donald'' has cognates in other Celtic languages: Modern Irish ''Dónal'' (anglicised as ''Donal'' and ''Donall'');. Scottish Gaelic ''Dòmhnall'', ''Domhnull'' and ''Dòmhnull''; Welsh '' Dyfnwal'' and Cumbric ''Dumnagual''. Although the feminine given name ''Donna'' is sometimes used as a feminine form of ''Donald'', the names are not etymologically related. Variations Kings and noblemen Domnall or Domhnall is the name of many ancie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Name (zoology)
In zoological nomenclature, the specific name (also specific epithet or species epithet) is the second part (the second name) within the scientific name of a species (a binomen). The first part of the name of a species is the name of the genus or the generic name. The rules and regulations governing the giving of a new species name are explained in the article species description. For example, the scientific name for humans is ''Homo sapiens'', which is the species name, consisting of two names: ''Homo'' is the " generic name" (the name of the genus) and ''sapiens'' is the "specific name". Historically, ''specific name'' referred to the combination of what are now called the generic and specific names. Carl Linnaeus, who formalized binomial nomenclature, made explicit distinctions between specific, generic, and trivial names. The generic name was that of the genus, the first in the binomial, the trivial name was the second name in the binomial, and the specific the proper term for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Name Of A Biological Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. phylogenetic analysis should clearly demonstr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Derived Trait
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor. ) In cladistics, synapomorphy implies homology. Examples of apomorphy are the presence of erect gait, fur, the evolution of three middle ear bones, and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles, which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. Etymology The word —coined by German entomologist Willi Hennig—is derived from the Ancient Greek words (''sún''), meaning "with, together"; (''apó''), meaning "away from"; and (''morphḗ''), meaning "shape, form". Clade analysis Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tribe (biology)
In biology, a tribe is a taxonomic rank above genus, but below family and subfamily. It is sometimes subdivided into subtribes. By convention, all taxonomic ranks from genus upwards are capitalized, including both tribe and subtribe. In zoology, the standard ending for the name of a zoological tribe is "-ini". Examples include the tribes Caprini (goat-antelopes), Hominini (hominins), Bombini (bumblebees), and Thunnini (tunas). The tribe Hominini is divided into subtribes by some scientists; subtribe Hominina then comprises "humans". The standard ending for the name of a zoological subtribe is "-ina". In botany, the standard ending for the name of a botanical tribe is "-eae". Examples include the tribes Acalypheae and Hyacintheae. The tribe Hyacintheae is divided into subtribes, including the subtribe Massoniinae. The standard ending for the name of a botanical subtribe is "-inae". In bacteriology, the form of tribe names is as in botany, e.g., Pseudomonadeae, based on the ge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
