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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] |
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] |
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] |
Ypresian
In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by the Eocene Lutetian Age. The Ypresian is consistent with the Lower Eocene (Early Eocene). Events The Ypresian Age begins during the throes of the Paleocene–Eocene Thermal Maximum (PETM). The Fur Formation in Denmark, the Messel shales in Germany, the Oise amber of France and Cambay amber of India are of this age. The Eocene Okanagan Highlands are an uplands subtropical to temperate series of lakes from the Ypresian. The Ypresian is additionally marked by another warming event called the Early Eocene Climatic Optimum (EECO). The EECO is the longest sustained warming event in the Cenozoic record, lasting about 2–3 million years between 53 and 50 Ma. The interval is characterized by low oxygen-18 isotopes, high levels of atmospheric pCO2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canine Tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, eye teeth, vampire teeth, or fangs, are the relatively long, pointed teeth. In the context of the upper jaw, they are also known as '' fangs''. They can appear more flattened, however, causing them to resemble incisors and leading them to be called ''incisiform''. They developed and are used primarily for firmly holding food in order to tear it apart, and occasionally as weapons. They are often the largest teeth in a mammal's mouth. Individuals of most species that develop them normally have four, two in the upper jaw and two in the lower, separated within each jaw by incisors; humans and dogs are examples. In most species, canines are the anterior-most teeth in the maxillary bone. The four canines in humans are the two upper maxillary canines and the two lower mandibular canines. They are specially prominent in dogs (Canidae), hence the name. Details There are generally four canine teeth: two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Premolar
The premolars, also called premolar Tooth (human), teeth, or bicuspids, are transitional teeth located between the Canine tooth, canine and Molar (tooth), molar teeth. In humans, there are two premolars per dental terminology#Quadrant, quadrant in the permanent teeth, permanent set of teeth, making eight premolars total in the mouth. They have at least two Cusp (dentistry), cusps. Premolars can be considered transitional teeth during chewing, or mastication. They have properties of both the canines, that lie anterior and molars that lie Posterior (anatomy), posterior, and so food can be transferred from the canines to the premolars and finally to the molars for grinding, instead of directly from the canines to the molars. Human anatomy The premolars in humans are the maxillary first premolar, maxillary second premolar, mandibular first premolar, and the mandibular second premolar. Premolar teeth by definition are permanent teeth Anatomical terms of location#Proximal and distal, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cingulum (tooth)
In dentistry, cingulum (Latin: girdle) is an anatomical feature of the tooth and referred to as the small raised area of an anterior tooth, including central incisors, lateral incisors and canines). It makes up the bulk of the tooth near the gum line and is located at the back (tongue side) of the tooth. The convexity of the cingulum from one side of the tooth to the other side resembles a girdle circling the back of the tooth at the cervical third of the anatomical crown. The cingulum represents the developmental lobes at the back of the teeth. The tooth crown develops from primary growth centres known as developmental lobes. Normal teeth generally consist of three to five lobes. In anterior teeth, generally the front side of the teeth develops from three lobes known as facial lobes while the back side of the teeth develops from one lobe known as the lingual lobe. The cingulum develops from the lingual lobe. As the tooth matures over time, the cingulum eventually becomes more defin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cusp (anatomy)
A cusp is a pointed, projecting, or elevated feature. In animals, it is usually used to refer to raised points on the crowns of teeth. The concept is also used with regard to the leaflets of the four heart valves. The mitral valve, which has two cusps, is also known as the bicuspid valve, and the tricuspid valve has three cusps. In humans A cusp is an occlusal or incisal eminence on a tooth. Canine teeth, otherwise known as cuspids, each possess a single cusp, while premolars, otherwise known as bicuspids, possess two each. Molars normally possess either four or five cusps. In certain populations the maxillary molars, especially first molars, will possess a fifth cusp situated on the mesiolingual cusp known as the Cusp of Carabelli. One other variation of the upper first premolar is the 'Uto-Aztecan' upper premolar. It is a bulge on the buccal cusp that is only found in Native American Indians, with highest frequencies of occurrence in Arizona. The name is not a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy (biology)
In biology, taxonomy () is the science, scientific study of naming, defining (Circumscription (taxonomy), circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxon, taxa (singular: taxon), and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain (biology), domain, kingdom (biology), kingdom, phylum (''division'' is sometimes used in botany in place of ''phylum''), class (biology), class, order (biology), order, family (biology), family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, having developed a ranked system known as Linnaean taxonomy for categorizing organisms. With advances in the theory, data and analytical technology of biological systematics, the Linnaean system has transfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetics
In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical data and observed heritable traits of DNA sequences, protein amino acid sequences, and morphology. The results are a phylogenetic tree—a diagram depicting the hypothetical relationships among the organisms, reflecting their inferred evolutionary history. The tips of a phylogenetic tree represent the observed entities, which can be living taxa or fossils. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the taxa represented on the tree. An unrooted tree diagram (a network) makes no assumption about directionality of character state transformation, and does not show the origin or "root" of the taxa in question. In addition to their use for inferring phylogenetic pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apomorphy And Synapomorphy
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 Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
