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Dendrerpeton Acadianum
''Dendrerpeton'' (from el, δένδρον , 'tree' and el, ἑρπετόν , 'creeping thing') is a genus of an extinct group of temnospondyl amphibians. Its fossils have been found primarily in the Joggins Formation of Eastern Canada and in Ireland. It lived during the Carboniferous and is said to be around 309–316 million years of age, corresponding to more specifically the Westphalian (stage) age. Of terrestrial temnospondyl amphibians evolution, it represents the first stage. Although multiple species have been proposed, the species unanimously recognized is ''D. acadianum''. This species name comes from “Acadia” which is a historical name for the Nova Scotia region as a French colony. It refers to the location of the coal field at which the fossil was found. History and discovery The majority of ''Dendrerpeton'' fossils that had been discovered were disarticulated due to the way in which they had formed. They are often associated with Lycopod, Sigillaria, and Cala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferous'' means "coal-bearing", from the Latin '' carbō'' ("coal") and '' ferō'' ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern 'system' names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. The Carboniferous is often treated in North America as two geological periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Tetrapods (four limbed vertebrates), which had originated from lobe-finned fish during the preceding Devonian, became pentadactylous in and diversified during the Carboniferous, including early amphibian line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calamites
''Calamites'' is a genus of extinct arborescent (tree-like) horsetails to which the modern horsetails (genus ''Equisetum'') are closely related. Unlike their herbaceous modern cousins, these plants were medium-sized trees, growing to heights of 30-50 meters (100-160 feet). They were components of the understories of coal swamps of the Carboniferous Period (around ). Taxonomy A number of organ taxa have been identified as part of a united organism, which has inherited the name ''Calamites'' in popular culture. ''Calamites'' correctly refers only to casts of the stem of Carboniferous/Permian sphenophytes, and as such is a form genus of little taxonomic value. There are two forms of casts, which can give mistaken impressions of the organisms. The most common is an internal cast of the hollow (or pith-filled) void in the centre of the trunk. This can cause some confusion: firstly, it must be remembered that a fossil was probably surrounded with 4-5 times its width in (unpres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eardrum
In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear The outer ear, external ear, or auris externa is the external part of the ear, which consists of the auricle (also pinna) and the ear canal. It gathers sound energy and focuses it on the eardrum (tympanic membrane). Structure Auricle The ... from the middle ear. Its function is to transmit sound from the air to the ossicles inside the middle ear, and then to the oval window in the fluid-filled cochlea. Hence, it ultimately converts and amplifies vibration in the air to vibration in cochlear fluid. The malleus bone bridges the gap between the eardrum and the other ossicles. Rupture or perforation of the eardrum can lead to conductive hearing loss. Collapse or tympanic membrane retraction, retraction of the eardrum can cause conductive hearing loss or cholesteatoma. Structure Orientation and r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxon
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were set forth in Carl Linnaeus's Linnaean taxonomy, system in ''Systema Naturae'', 10th edition (1758), as well as an unpublished work by Bernard de Jussieu, Bernard and Antoine Laurent de Jussieu. The idea of a unit-based system of biological classification was first mad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrerpeton Acadianum
''Dendrerpeton'' (from el, δένδρον , 'tree' and el, ἑρπετόν , 'creeping thing') is a genus of an extinct group of temnospondyl amphibians. Its fossils have been found primarily in the Joggins Formation of Eastern Canada and in Ireland. It lived during the Carboniferous and is said to be around 309–316 million years of age, corresponding to more specifically the Westphalian (stage) age. Of terrestrial temnospondyl amphibians evolution, it represents the first stage. Although multiple species have been proposed, the species unanimously recognized is ''D. acadianum''. This species name comes from “Acadia” which is a historical name for the Nova Scotia region as a French colony. It refers to the location of the coal field at which the fossil was found. History and discovery The majority of ''Dendrerpeton'' fossils that had been discovered were disarticulated due to the way in which they had formed. They are often associated with Lycopod, Sigillaria, and Cala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metre
The metre (British spelling) or meter (American spelling; see spelling differences) (from the French unit , from the Greek noun , "measure"), symbol m, is the primary unit of length in the International System of Units (SI), though its prefixed forms are also used relatively frequently. The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole along a great circle, so the Earth's circumference is approximately km. In 1799, the metre was redefined in terms of a prototype metre bar (the actual bar used was changed in 1889). In 1960, the metre was redefined in terms of a certain number of wavelengths of a certain emission line of krypton-86. The current definition was adopted in 1983 and modified slightly in 2002 to clarify that the metre is a measure of proper length. From 1983 until 2019, the metre was formally defined as the length of the path travelled by light in a vacuum in of a second. After the 2019 redefi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stratum
In geology and related fields, a stratum ( : strata) is a layer of rock or sediment characterized by certain lithologic properties or attributes that distinguish it from adjacent layers from which it is separated by visible surfaces known as either '' bedding surfaces'' or ''bedding planes''.Salvador, A. ed., 1994. ''International stratigraphic guide: a guide to stratigraphic classification, terminology, and procedure. 2nd ed.'' Boulder, Colorado, The Geological Society of America, Inc., 215 pp. . Prior to the publication of the International Stratigraphic Guide, older publications have defined a stratum as either being either equivalent to a single bed or composed of a number of beds; as a layer greater than 1 cm in thickness and constituting a part of a bed; or a general term that includes both ''bed'' and ''lamina''.Neuendorf, K.K.E., Mehl, Jr., J.P., and Jackson, J.A. , eds., 2005. ''Glossary of Geology'' 5th ed. Alexandria, Virginia, American Geological Institute. 779 pp. . ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erosion Surface
In geology and geomorphology, an erosion surface is a surface of rock or regolith that was formed by erosion and not by construction (e.g. lava flows, sediment deposition) nor fault displacement. Erosional surfaces within the stratigraphic record are known as unconformities, but not all unconformities are buried erosion surfaces. Erosion surfaces vary in scale and can be formed on a mountain range or a rock. Particularly large and flat erosion surfaces receive the names of peneplain, paleoplain, planation surface or pediplain. An example of erosion surface is road surface erosion which is caused by natural and anthropogenic factors. Erosion surface can be measured through direct, contact measurement methods and indirect, non-contact measurement methods. Road surface erosion Just like mountains and rocks, erosion can also occur on unsealed roads due to natural and anthropogenic factors. Road surface erosion could be caused by snowfall, rainfall and wind. The material and hydr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecosystem
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the system through photosynthesis and is incorporated into plant tissue. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and microbes. Ecosystems are controlled by external and internal factors. External factors such as climate, parent material which forms the soil and topography, control the overall structure of an ecosystem but are not themselves influenced by the ecosystem. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denderpeton DB
''Dendrerpeton'' (from el, δένδρον , 'tree' and el, ἑρπετόν , 'creeping thing') is a genus of an extinct group of temnospondyl amphibians. Its fossils have been found primarily in the Joggins Formation of Eastern Canada and in Ireland. It lived during the Carboniferous and is said to be around 309–316 million years of age, corresponding to more specifically the Westphalian (stage) age. Of terrestrial temnospondyl amphibians evolution, it represents the first stage. Although multiple species have been proposed, the species unanimously recognized is ''D. acadianum''. This species name comes from “Acadia” which is a historical name for the Nova Scotia region as a French colony. It refers to the location of the coal field at which the fossil was found. History and discovery The majority of ''Dendrerpeton'' fossils that had been discovered were disarticulated due to the way in which they had formed. They are often associated with Lycopod, Sigillaria, and Cala ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boulder
In geology, a boulder (or rarely bowlder) is a rock fragment with size greater than in diameter. Smaller pieces are called cobbles and pebbles. While a boulder may be small enough to move or roll manually, others are extremely massive. In common usage, a boulder is too large for a person to move. Smaller boulders are usually just called rocks or stones. The word ''boulder'' derives from ''boulder stone'', from the Middle English ''bulderston'' or Swedish ''bullersten''. Online Etymology Dictionary. Retrieved December 9, 2011, from Dictionary.com website. In places covered by s during s, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
