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Khirtharia
''Khirtharia'' is an extinct genus of raoellid artiodactyl that inhabited what is now northern India and Pakistan during the middle-upper Eocene (early Lutetian, 48 to 45 million years ago). There are three species of ''Khirtharia'': ''K. dayi,'' ''K. inflata,'' and ''K. aurea''. There is also a possible fourth species, ''K. major''. ''Khirtharia'' is found primarily from Jammu and Kashmir and Northern Pakistan. More specifically, it is most commonly found in the Upper Subathu Group within Jammu and Kashmir. ''Khirtharia'' is notable for a well preserved skull of ''K. inflata'', which allowed for obtaining an endocranial cast of the brain cavity. The endocranial cast of ''K. inflata'' showed that the brain of ''Khirtharia'' was slightly smaller than that of the related ''Indohyus.'' The brain cavity had a volume of approximately 5.5 cubic centimeters, less than in contemporary artiodactyls, giving strong evidence that whales evolved from artiodactyls of relatively small brain si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raoellidae
Raoellidae, previously grouped within Helohyidae, are an extinct family of semiaquatic digitigrade artiodactyls in the clade Whippomorpha. Fossils of Raoellids are found in Eocene strata of South Asia and Southeast Asia. An exceptionally complete skeleton of ''Indohyus,'' the best preserved Raoellid, from Kashmir suggests that Raoellids are the " missing link" sister group to whales (Cetacea). All other Artiodactyla are relatives of these two groups. δO18 values and osteosclerotic bones indicate that the raccoon-like ''Indohyus'' was habitually aquatic. However, it is still unclear if ''Indohyus'' primarily fed on land or in water. It is hypothesized that cetaceans evolved from ancestors similar to Raoellids and later fully adapted to aquatic life. Taxonomy *'' Rajouria'' **''Rajouria gunnelli'' *'' Haqueina?'' **''Haqueina haquei'' **''Haqueina haichinensis'' *''Indohyus'' **''Indohyus indirae'' **''Indohyus major?'' *'' Kunmunella'' **''Kunmunella kalakotensis'' **''Kunmunella ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rajouria
''Rajouria'', named after the Rajouri district in the Indian province of Jammu and Kashmir, is an extinct raoellid artiodactyl from the middle-upper Eocene (early Lutetian). There is only a single species of ''Rajouria'', ''Rajouria gunnelli'', which is named after Dr. Greg Gunnell. ''Rajouria'' is known from relatively little remains, with only mandibular and maxillary fragments with their respective teeth being preserved. Discovery ''Rajouria'' was discovered near the town of Aiji in the East-Aiji 2 locality. The initial remains of ''Rajouria'' were all found in proximity to each other and are the only remains assigned to ''Rajouria''. Classification When it was first discovered, ''Rajouria'' was placed within Raoellidae. Its position as a raoellid has remained stable, although it is not certain where exactly it is within Raoellidae. In the phylogenetic analysis of Raoellidae by Rana et al., ''Rajouria'' was placed as the most basal raoellid due to the presence of the par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kunmunella
''Kunmunella'' is an extinct raoellid artiodactyl which inhabited what is now northern India during the middle-upper Eocene (Ypresian). There are two species of ''Kunmunella'': ''K. kalakotensis'' and ''K. transversa''. The former species was named after the town of Kalakote within Jammu and Kashmir, the place from which it was found, while the latter species was named after the transverse nature of the upper teeth. ''K. kalakotensis'' is known from a palate with its respective teeth, a left maxillary ramus, a left mandible, two poorly preserved maxillas, and two isolated molars. ''K. transversa'' is known from only a right maxilla. Discovery The remains of ''Kunmunella'' were first found by Ranga Rao, 1971. He found only a left mandible, and assigned it to a new species of ''Indohyus'', ''I. kalakotensis'', after the region in which he discovered the animal. In the following year, an isolated upper third molar would be found by Sahni and Khare, which would be assigned to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lutetian
The Lutetian is, in the geologic timescale, a stage (stratigraphy), stage or age (geology), age in the Eocene. It spans the time between . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it is sometimes referred to as the Middle Eocene Subepoch. Stratigraphic definition The Lutetian was named after Lutetia, the Latin language, Latin name for the city of Paris. The Lutetian Stage was introduced in scientific literature by French geologist Albert de Lapparent in 1883 and revised by A. Blondeau in 1981. The base of the Lutetian Stage is at the first appearance of the nanofossil ''Blackites inflatus'', according to an official reference profile (GSSP) established in 2011. Of two candidates located in Spain, the Gorrondatxe section was chosen.See thwebsite of Eustoquio Molinafor these candidates. The top of the Lutetian (the base of the Bartonian) is at the first appearance of calcareous nannofossils, calcareous nanoplankton s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
In vertebrates, the maxilla (: maxillae ) is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Anatomy Structure The maxilla is a paired bone - the two maxillae unite with each other at the intermaxillary suture. The maxilla consists of: * The body of the maxilla: pyramid-shaped; has an orbital, a nasal, an infratemporal, and a facial surface; contains the maxillary sinus. * Four processes: ** the zygomatic process ** the frontal process ** the alveolar process ** the palatine process It has three surfaces: * the anterior, posterior, medial Features of the maxilla include: * t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foramen
In anatomy and osteology, a foramen (; : foramina, or foramens ; ) is an opening or enclosed gap within the dense connective tissue (bones and deep fasciae) of extant and extinct amniote animals, typically to allow passage of nerves, artery, arteries, veins or other soft tissue structures (e.g. muscle tendon) from one body compartment to another. Skull The skulls of vertebrates have foramina through which nerves, arteries, veins, and other structures pass. The human skull has many foramina, collectively referred to as the cranial foramina. Spine Within the vertebral column (spine) of vertebrates, including the Human vertebral column, human spine, each bone has an opening at both its top and bottom to allow nerves, arteries, veins, etc. to pass through. Other * Apical foramen, the hole at the tip of the root of a tooth * Foramen ovale (heart), a hole between the venous and arterial sides of the fetal heart * Vertebra#Cervical vertebrae, Transverse foramen, one of a pair ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (biology)
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative '' phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Ford E.B. 1965. ''Genetic polymorphism''. Faber & Faber, London. Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area around Rome, Italy. Through the expansion of the Roman Republic, it became the dominant language in the Italian Peninsula and subsequently throughout the Roman Empire. It has greatly influenced many languages, Latin influence in English, including English, having contributed List of Latin words with English derivatives, many words to the English lexicon, particularly after the Christianity in Anglo-Saxon England, Christianization of the Anglo-Saxons and the Norman Conquest. Latin Root (linguistics), roots appear frequently in the technical vocabulary used by fields such as theology, List of Latin and Greek words commonly used in systematic names, the sciences, List of medical roots, suffixes and prefixes, medicine, and List of Latin legal terms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metkatius
''Metkatius'', named after the town of Metka in the province Jammu and Kashmir, is a small extinct raoellid artiodactyl which inhabited northern India during the Middle Eocene (48-45 Mya) during the Early Lutetian age. Metkatius is known from fragmentary remains, with the only discovered fossil remains being mandibular and maxillary fragments and isolated teeth, mainly belonging to juvenile specimens and a portion of the skeleton of a juvenile, a fragmentary skull, vertabrae, and a forelimb. There is only one accepted species of ''Metkatius'', ''M. kashmiriensis'', which is named after Kashmir. Discovery ''Metkatius'' was described by Kumar and Sahni in 1985. The holotype specimen VPL/K 562 consists of an anterior portion of the skeleton of a juvenile, a fragmentary and warped skull, six vertabrae (the seventh was presumably destroyed during fossilization), and a forelimb. The holotype specimen was found in Grey sandstone in the Upper Subathu formation. Description ''Met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. 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 taxonomy (biology), 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. Phylogeneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichobunidae
Dichobunidae is an extinct family of basal artiodactyl mammals from the early Eocene to late Oligocene of North America, Europe, and Asia. The Dichobunidae include some of the earliest known artiodactyls, such as ''Diacodexis''. Description They were small animals, averaging about the size of a modern rabbit, and had many primitive features. In life, they would have resembled a long-tailed muntjac or chevrotain. Dichobunids had four or five toes on each foot, with each toe ending in a small hoof. They had complete sets of teeth, unlike most later artiodactyls, with their more specialist dentitions. The shape of the teeth suggests they were browsers, feeding on small leaves, perhaps in the forest undergrowth. The shape of their bodies and limbs suggests they would have been fast-running animals, unlike most of their contemporaries. Taxonomy Classification of dichobunids following McKenna and Bell: *† Family Dichobunidae **'' Paraphenacodus'' **'' Dulcidon'' **'' Chorlakkia' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
