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Adeilosmilus
''Amphimachairodus'' is an extinct genus of large machairodonts. It is also a member of the tribe Homotherini within Machairodontinae and is most closely related to such species as ''Xenosmilus'', ''Homotherium'' itself, and ''Nimravides''. It inhabited Eurasia, Northern Africa and North America during the late Miocene epoch. Description There was marked sexual dimorphism in ''A. giganteus'', with males being much larger than females. The species ''Amphimachairodus coloradensis'', from the United States (formerly ''Machairodus coloradensis'') was a significantly large animal, about at the shoulder, according to skeletal and life reconstructions, potentially making it one of the largest known felids. All ''Amphimachairodus'' species have a developed mandibular flange, however, ''A. colaradensis'' is distinguishable from ''A. giganteus'' and ''A. kurteni'' by subtle differences in the shape of the mandible and placement of lower carnassials. In size and proportions, the Euras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenosmilus
''Xenosmilus hodsonae'' (from Greek, , ''xenos'', "strange" + , ''smilē'', " chisel" ) is an extinct species of the Machairodontinae, or saber-toothed cats. Description The species name ''hodsonae'' originates from Debra Hodson, the wife of a researcher. Two fairly intact specimens were found by amateur fossil hunters in 1983 (1981 by some sources) in the Haile limestone mines in Alachua County, Florida. In 1994, the fossils were examined, and it was decided that the cats were of an entirely new genus. The fossils were of Irvingtonian age (1.8 to 0.3 Ma). Because the skeletons were found beside each other, some suspect ''Xenosmilus'' was a social mammal. Found alongside the two skeletons were dozens of peccary bones. It seems likely, with their muscular builds, that ''X. hodsonae'' preyed upon peccaries. Physically, the cat reached around long with a highly muscular body and weighed around , making it similar in size to the fellow machairodonts '' Machairodus horribili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machairodus Palanderi
''Amphimachairodus'' is an extinct genus of large machairodonts. It is also a member of the tribe Homotherini within Machairodontinae and is most closely related to such species as ''Xenosmilus'', ''Homotherium'' itself, and ''Nimravides''. It inhabited Eurasia, Northern Africa and North America during the late Miocene epoch. Description There was marked sexual dimorphism in ''A. giganteus'', with males being much larger than females. The species ''Amphimachairodus coloradensis'', from the United States (formerly ''Machairodus coloradensis'') was a significantly large animal, about at the shoulder, according to skeletal and life reconstructions, potentially making it one of the largest known felids. All ''Amphimachairodus'' species have a developed mandibular flange, however, ''A. colaradensis'' is distinguishable from ''A. giganteus'' and ''A. kurteni'' by subtle differences in the shape of the mandible and placement of lower carnassials. In size and proportions, the Eurasian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphimachairodus Giganteus Forefoot
''Amphimachairodus'' is an extinct genus of large machairodonts. It is also a member of the tribe Homotherini within Machairodontinae and is most closely related to such species as ''Xenosmilus'', ''Homotherium'' itself, and ''Nimravides''. It inhabited Eurasia, Northern Africa and North America during the late Miocene epoch. Description There was marked sexual dimorphism in ''A. giganteus'', with males being much larger than females. The species ''Amphimachairodus coloradensis'', from the United States (formerly ''Machairodus coloradensis'') was a significantly large animal, about at the shoulder, according to skeletal and life reconstructions, potentially making it one of the largest known felids. All ''Amphimachairodus'' species have a developed mandibular flange, however, ''A. colaradensis'' is distinguishable from ''A. giganteus'' and ''A. kurteni'' by subtle differences in the shape of the mandible and placement of lower carnassials. In size and proportions, the Eurasian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Miocene
The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million years ago) to 5.333 Ma. The evolution of life The gibbons (family Hylobatidae) and orangutans (genus ''Pongo'') are the first groups to split from the line leading to the hominins, including humans, then gorillas (genus ''Gorilla''), and finally, chimpanzees and bonobos (genus ''Pan (genus), Pan''). The splitting date between hominin and chimpanzee lineages is placed by some between 4 to 8 million years ago, that is, during the Late Miocene. References External links GeoWhen Database - Late Miocene Miocene, .03 Miocene geochronology, 03 Messinian, * Tortonian, * {{geochronology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tiger
The tiger (''Panthera tigris'') is the largest living cat species and a member of the genus '' Panthera''. It is most recognisable for its dark vertical stripes on orange fur with a white underside. An apex predator, it primarily preys on ungulates, such as deer and wild boar. It is territorial and generally a solitary but social predator, requiring large contiguous areas of habitat to support its requirements for prey and rearing of its offspring. Tiger cubs stay with their mother for about two years and then become independent, leaving their mother's home range to establish their own. The tiger was first scientifically described in 1758. It once ranged widely from the Eastern Anatolia Region in the west to the Amur River basin in the east, and in the south from the foothills of the Himalayas to Bali in the Sunda Islands. Since the early 20th century, tiger populations have lost at least 93% of their historic range and have been extirpated from Western and Central Asia, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Formula
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology (that is, the relationship between the shape and form of the tooth in question and its inferred function) of the teeth of an animal. Animals whose teeth are all of the same type, such as most non-mammalian vertebrates, are said to have '' homodont'' dentition, whereas those whose teeth differ morphologically are said to have '' heterodont'' dentition. The dentition of animals with two successions of teeth (deciduous, permanent) is referred to as '' diphyodont'', while the dentition of animals with only one set of teeth throughout life is ''monophyodont''. The dentition of animals in which the teeth are continuously discarded and replaced throughout life is termed ''polyphyodont''. The dentition of animals in which the teeth are set in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megantereon
''Megantereon'' was a genus of prehistoric machairodontine saber-toothed cat that lived in North America, Eurasia, and Africa. It may have been the ancestor of ''Smilodon''. Taxonomy Fossil fragments have been found in Africa, Eurasia, and North America. It also ranged into southernmost China as well, as a mostly complete skull from Sabretooth Cave, Chongzuo indicates, though it seemed to have been rare in most of Asia due to being ill-adapted to closed forest environments. The oldest confirmed records of ''Megantereon'' are known from the Pliocene of North America and are dated to about 4.5 million years. About 3–3.5 million years ago, it is firmly recorded also from Africa (for example, in Kenya), about 2.5 to 2 million years ago also from Asia. In Europe the oldest remains are known from Les Etouaries (France), a site which is now dated to less than 2.5 million years old. Therefore, a North American origin of ''Megantereon'' has been suggested. However, recent findings of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nasal Bone
The nasal bones are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face and by their junction, form the bridge of the upper one third of the nose. Each has two surfaces and four borders. Structure The two nasal bones are joined at the midline internasal suture and make up the bridge of the nose. Surfaces The ''outer surface'' is concavo-convex from above downward, convex from side to side; it is covered by the procerus and nasalis muscles, and perforated about its center by a foramen, for the transmission of a small vein. The ''inner surface'' is concave from side to side, and is traversed from above downward, by a groove for the passage of a branch of the nasociliary nerve. Articulations The nasal articulates with four bones: two of the cranium, the frontal and ethmoid, and two of the face, the opposite nasal and the maxilla. Other animals In primitive bony fish and tetrapod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is , of which the eye occupies . The orbital contents comprise the eye, the orbital and retrobulbar fascia, extraocular muscles, cranial nerves II, III, IV, V, and VI, blood vessels, fat, the lacrimal gland with its sac and duct, the eyelids, medial and lateral palpebral ligaments, cheek ligaments, the suspensory ligament, septum, ciliary ganglion and short ciliary nerves. Structure The orbits are conical or four-sided pyramidal cavities, which open into the midline of the face and point back into the head. Each consists of a base, an apex and four walls."eye, human."Encyclopædia Britannica from Encyclopædia Britannica 2006 Ultimate Reference Suite DVD 2009 Openings There are two important foramina, or windows, two important fissu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagittal Crest
A sagittal crest is a ridge of bone running lengthwise along the midline of the top of the skull (at the sagittal suture) of many mammalian and reptilian skulls, among others. The presence of this ridge of bone indicates that there are exceptionally strong jaw muscles. The sagittal crest serves primarily for attachment of the temporalis muscle, which is one of the main chewing muscles. Development of the sagittal crest is thought to be connected to the development of this muscle. A sagittal crest usually develops during the juvenile stage of an animal in conjunction with the growth of the temporalis muscle, as a result of convergence and gradual heightening of the temporal lines. Function A sagittal crest tends to be present on the skulls of adult animals that rely on powerful biting and clenching of their teeth, usually as a part of their hunting strategy. Skulls of some dinosaur species, including tyrannosaurs, possessed well developed sagittal crests. Among mammals, dogs, cats, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zygomatic Arch
In anatomy, the zygomatic arch, or cheek bone, is a part of the skull formed by the zygomatic process of the temporal bone (a bone extending forward from the side of the skull, over the opening of the ear) and the temporal process of the zygomatic bone (the side of the cheekbone), the two being united by an oblique suture (the zygomaticotemporal suture); the tendon of the temporal muscle passes medial to (i.e. through the middle of) the arch, to gain insertion into the coronoid process of the mandible (jawbone). The jugal point is the point at the anterior (towards face) end of the upper border of the zygomatic arch where the masseteric and maxillary edges meet at an angle, and where it meets the process of the zygomatic bone. The arch is typical of '' Synapsida'' (“fused arch”), a clade of amniotes that includes mammals and their extinct relatives, such as ''Moschops'' and '' Dimetrodon''. Structure The zygomatic process of the temporal arises by two roots: * an ''anter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neontology
Neontology is a part of biology that, in contrast to paleontology, deals with living (or, more generally, '' recent'') organisms. It is the study of extant taxa (singular: extant taxon): taxa (such as species, genera and families) with members still alive, as opposed to (all) being extinct. For example: * The moose (''Alces alces'') is an extant species, and the dodo (''Raphus cucullatus'') is an extinct species. * In the group of molluscs known as the cephalopods, there were approximately 600 extant species and 7,500 extinct species. A taxon can be classified as extinct if it is broadly agreed or certified that no members of the group are still alive. Conversely, an extinct taxon can be reclassified as extant if there are new discoveries of living species ("Lazarus species"), or if previously-known extant species are reclassified as members of the taxon. Most biologists, zoologists, and botanists are in practice neontologists, and the term neontologist is used largel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
