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Djarthia Murgonensis
''Djarthia'' is an extinct monotypic genus of marsupial. It is the oldest marsupial found in Australia, discovered at the Murgon fossil site in south-eastern Queensland. ''D.'' ''murgonensis'' was described from material identified as Early Eocene Tingamarran fauna, first published in 1999. It was placed with the clade Australidelphia, which includes the marsupials that dispersed throughout Eastern Gondwanan supercontinent during the Eocene and remain extant in Australia and South America. Skeletal material described include a Molar (tooth), molar, incomplete cochlear and Tarsus (skeleton), tarsal bone either complete or in fragmented state of preservation. References {{Taxonbar, from=Q5285248 Australidelphia Eocene mammals of Australia Eocene marsupials Transitional fossils Fossil taxa described in 1999 Prehistoric marsupial genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene
The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). 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'', 'Eos, Dawn') and (''kainós'', "new") and refers to the "dawn" of modern ('new') fauna that appeared during the epoch.See: *Letter from William Whewell to Charles Lyell dated 31 January 1831 in: * From p. 55: "The period next antecedent we shall call Eocene, from ήως, aurora, and χαινος, recens, because the extremely small proportion of living species contained in these strata, indicates what may be considered the first commencement, or ''dawn'', of the existing state of the animate creation." 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 isoto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molar (tooth)
The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone tooth", from ''mola'', millstone and ''dens'', tooth. Molars show a great deal of diversity in size and shape across the mammal groups. The third molar of humans is sometimes vestigial. Human anatomy In humans, the molar teeth have either four or five cusps. Adult humans have 12 molars, in four groups of three at the back of the mouth. The third, rearmost molar in each group is called a wisdom tooth. It is the last tooth to appear, breaking through the front of the gum at about the age of 20, although this varies among individuals and populations, and in many cases the tooth is missing. The human mouth contains upper (maxillary) and lower (mandibular) molars. They are: maxillary first molar, maxillary second molar, maxillary third mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transitional Fossils
A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. This is especially important where the descendant group is sharply differentiated by gross anatomy and mode of living from the ancestral group. These fossils serve as a reminder that taxonomic divisions are human constructs that have been imposed in hindsight on a continuum of variation. Because of the incompleteness of the fossil record, there is usually no way to know exactly how close a transitional fossil is to the point of divergence. Therefore, it cannot be assumed that transitional fossils are direct ancestors of more recent groups, though they are frequently used as models for such ancestors. In 1859, when Charles Darwin's ''On the Origin of Species'' was first published, the fossil record was poorly known. Darwin described the perceived lack of transitional fossils as "the most obvious and gravest objection which can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eocene Marsupials
The Eocene ( ) is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic 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.See: *Letter from William Whewell to Charles Lyell dated 31 January 1831 in: * From p. 55: "The period next antecedent we shall call Eocene, from ήως, aurora, and χαινος, recens, because the extremely small proportion of living species contained in these strata, indicates what may be considered the first commencement, or ''dawn'', of the existing state of the animate creation." 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 13C in the atmosphere was exceptionally low in comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Public Library Of Science
PLOS (for Public Library of Science; PLoS until 2012) is a nonprofit publisher of open-access journals in science, technology, and medicine and other scientific literature, under an open-content license. It was founded in 2000 and launched its first journal, ''PLOS Biology'', in October 2003. As of 2024, PLOS publishes 14 academic journals, including 7 journals indexed within the Science Citation Index Expanded, and consequently 7 journals ranked with an impact factor. PLOS journals are included in the Directory of Open Access Journals (DOAJ). PLOS is also a member of the Open Access Scholarly Publishers Association (OASPA), a participating publisher and supporter of the Initiative for Open Citations, and a member of the Committee on Publication Ethics (COPE). History The Public Library of Science began in 2000 with an online petition initiative by Nobel Prize winner Harold Varmus, formerly director of the National Institutes of Health and at that time director of Mem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarsus (skeleton)
In the human body, the tarsus (: tarsi) is a cluster of seven articulating bones in each foot situated between the lower end of the tibia and the fibula of the lower leg and the metatarsus. It is made up of the midfoot (Cuboid bone, cuboid, medial, intermediate, and lateral cuneiform bone, cuneiform, and navicular) and hindfoot (Talus bone, talus and calcaneus). The tarsus articulates with the bones of the metatarsus, which in turn articulate with the proximal phalanges of the toes. The joint between the tibia and fibula above and the tarsus below is referred to as the ankle, ankle joint proper. In humans the largest bone in the tarsus is the calcaneus, which is the weight-bearing bone within the heel of the foot. Human anatomy Bones The talus bone or ankle bone is connected superiorly to the two bones of the lower leg, the tibia and fibula, to form the ankle, ankle joint or talocrural joint; inferiorly, at the subtalar joint, to the calcaneus or heel bone. Together, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cochlea
The cochlea is the part of the inner ear involved in hearing. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.75 turns around its axis, the modiolus (cochlea), modiolus. A core component of the cochlea is the organ of Corti, the sensory organ of hearing, which is distributed along the partition separating the fluid chambers in the coiled tapered tube of the cochlea. Etymology The name 'cochlea' is derived from the Latin word for ''snail shell'', which in turn is from the Greek language, Ancient Greek κοχλίας ''kokhlias'' ("snail, screw"), and from κόχλος ''kokhlos'' ("spiral shell") in reference to its coiled shape; the cochlea is coiled in mammals with the exception of monotremes. Structure The cochlea (: cochleae) is a spiraled, hollow, conical chamber of bone, in which waves propagate from the base (near the middle ear and the oval window) to the apex (the top or center of the spiral). The spiral canal of the cochlea is a section of the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gondwana
Gondwana ( ; ) was a large landmass, sometimes referred to as a supercontinent. The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia (continent), Australia, Zealandia, Arabian Peninsula, Arabia, and the Indian subcontinent. Gondwana was formed by the Accretion (geology), accretion of several cratons (large stable blocks of the Earth's crust), beginning with the East African Orogeny, the collision of India and Geography of Madagascar, Madagascar with East Africa, and culminating in with the overlapping Brasiliano orogeny, Brasiliano and Kuunga orogeny, Kuunga orogenies, the collision of South America with Africa, and the addition of Australia and Antarctica, respectively. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of some , about one-fifth of the Earth's surface. It fused with Laurasia during the Carboniferous to form Pan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Henk Godthelp
Henk is a Dutch male given name, originally a short form of Hendrik. It influenced " Hank" which is used in English-speaking countries (mainly in the US) as a form of "Henry". Academics *Henk Aertsen (born 1943), Dutch Anglo-Saxon linguist *Henk Barendregt (born 1947), Dutch logician *Henk Jaap Beentje (born 1951), Dutch botanist *Henk Blezer (born 1961), Dutch Tibetologist, Indologist, and scholar of Buddhist studies *Henk Bodewitz (1939–2022), Dutch Sanskrit scholar *Henk J. M. Bos (born 1940), Dutch historian of mathematics *Henk Braakhuis (born 1939), Dutch historian of philosophy *Henk Buck (1930–2023), Dutch organic chemist * Henk van Dongen (1936–2011), Dutch organizational theorist and policy advisor * Henk Dorgelo (1894–1961), Dutch physicist and academic *Henk van der Flier (born 1945), Dutch psychologist * Henk A. M. J. ten Have (born 1951), Dutch medical ethicist * Henk van de Hulst (1918–2000), Dutch astronomer and mathematician * Henk Lombaers (1920–2007 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australidelphia
Australidelphia is a superorder of marsupials encompassing about three-quarters of all living marsupial species, including all those native to Australasia and one South American species, the monito del monte. Unlike other American marsupials, which belong to the Ameridelphia, Australidelphia’s lineage emerged in South America, with genetic evidence (retrotransposon insertion sites) showing the monito del monte as its most ancient branch. Within this superorder, the Australian members form a distinct group (clade) named Eomarsupialia, though their internal relationships (branching order) is yet to be determined. Studies suggest Australidelphia originated in South America alongside other major marsupial groups, likely dispersing to Australia via Antarctica in a single event after the monito’s lineage ( Microbiotheria) diverged, leaving other South American orders (Didelphimorphia and Paucituberculata) as more basal. Phylogeny The following cladogram is a phylogeny of Aust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
