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Calcareous Nannofossils
Calcareous nannofossils are a class of tiny (less than 30 microns in diameter) microfossils that are similar to coccoliths deposited by the modern-day coccolithophores. The nannofossils are a convenient source of geochronological data due to the abundance and rapid evolution of the single-cell organisms forming them (nannoplankton) and ease of handling of the sediment samples. The practical applications of calcareous nannofossils in the areas of biostratigraphy and paleoecology became clear once the deepwater drilling took off in 1968 with the Deep Sea Drilling Project, and they have been extensively studied ever since. Nannofossils provide one of the most important paleontological records with the contiguous length of 220 million years. History of research Christian Gottfried Ehrenberg, while examining the chalk from Ruegen, recorded an observation of what was later termed "coccolith" in 1836 and had pictured the coccoliths and Discoasters in his ''Mikrogeologie'' (1854 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Discoaster Surculus 01
''Discoaster'' is a genus of extinct star-shaped marine algae, with calcareous exoskeletons of between 5-40 μm across that are abundant as nanofossils in tropical deep-ocean deposits of Neogene age. ''Discoaster'' belongs to the haptophytes. About 100 species can be recognized. Biostratigraphic significance The International Commission on Stratigraphy (ICS) has assigned the extinction of ''Discoaster brouweri'' as the defining biological marker for the start of the Calabrian Stage of the Pleistocene, 1.806 million years ago. ICS has assigned the extinction of ''Discoaster pentaradiatus'' and ''Discoaster surculus'' as the defining biological marker for the start of the Gelasian Stage, 2.588 million years ago, the earliest stage of the Pleistocene. ICS further assigned the extinction of ''Discoaster kugleri'' as biological marker for the start of the Tortonian Stage of the Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haematococcus Lacustris
''Haematococcus'' is a genus of algae in the family Haematococcaceae. Members of this group are a common cause of the pink color found in birdbaths. One of the most notable species of ''Haematococcus'' is ''H. pluvialis'', which is used in cosmetic products due to its production of astaxanthin, a powerful antioxidant carotenoid, under stress conditions. File:Haematococcus pluvialis.jpg, Drawing of '' Haematococcus pluvialis''Frank Shipley Collins. ''The Green Algae of North America'', Volume II of Tufts College Studies, Published by Tufts College, 1909, pp 79-480. From Plate II. File: Haematococcus pluvialis flagellate.jpg, Flagellate stage File:Haematococcus pluvialis 3.jpg, When stressed, this green microalgae, '' Haematococcus pluvialis'', degrades chlorophylls and accumulates a strong red antioxidant, the carotenoid astaxanthin Astaxanthin is a keto-carotenoid within a group of chemical compounds known as terpenes. Astaxanthin is a metabolite of zeaxanthin and can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biozone
In biostratigraphy, biostratigraphic units or biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa, as opposed to a lithostratigraphic unit which is defined by the lithological properties of the surrounding rock. A biostratigraphic unit is defined by the zone fossils it contains. These may be a single taxon or combinations of taxa if the taxa are relatively abundant, or variations in features related to the distribution of fossils. The same strata may be zoned differently depending on the diagnostic criteria or fossil group chosen, so there may be several, sometimes overlapping, biostratigraphic units in the same interval. Like lithostratigraphic units, biozones must have a type section designated as a stratotype. These stratotypes are named according to the typical taxon (or taxa) that are found in that particular biozone. The boundary of two distinct biostratigraphic units is called a ''biohorizon''. Biozones can be f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drilling Core
A core sample is a cylindrical section of (usually) a naturally-occurring substance. Most core samples are obtained by drilling with special drills into the substance, such as sediment or rock, with a hollow steel tube, called a core drill. The hole made for the core sample is called the "core hole". A variety of core samplers exist to sample different media under different conditions. More continue to be invented on a regular basis. In the coring process, the sample is pushed more or less intact into the tube. Removed from the tube in the laboratory, it is inspected and analyzed by different techniques and equipment depending on the type of data desired. Core samples can be taken to test the properties of manmade materials, such as concrete, ceramics, some metals and alloys, especially the softer ones. Core samples can also be taken of living things, including human beings, especially of a person's bones for microscopic examination to help diagnose diseases. Methods The comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milton Nunn Bramlette
Milton may refer to: Names * Milton (surname), a surname (and list of people with that surname) ** John Milton (1608–1674), English poet * Milton (given name) ** Milton Friedman (1912–2006), Nobel laureate in Economics, author of '' Free to Choose'' Places Australia * Milton, New South Wales * Milton, Queensland, a suburb of Brisbane ** Milton Courts, a tennis centre ** Milton House, Milton, a heritage-listed house ** Milton railway station, Brisbane ** Milton Reach, a reach of the Brisbane River ** Milton Road, an arterial road in Brisbane Canada * Milton, Newfoundland and Labrador * Milton, Nova Scotia in the Region of Queens Municipality * Milton, Ontario ** Milton line, a commuter train line ** Milton GO Station * Milton (electoral district), Ontario ** Milton (provincial electoral district), Ontario * Beaverton, Ontario a community in Durham Region and renamed as Beaverton in 1835 * Rural Municipality of Milton No. 292, Saskatchewan New Zealand * Mil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trygve Braarud
Trygve Braarud (15 September 1903 – 9 July 1985) was a Norwegian botanist. He specialized in marine biology, and was affiliated with the University of Oslo for most of his career. Career He was born in Verdal, and had ten older siblings as well as a twin sister. He received some of his early schooling at a private teaching institution founded by his father. He finished his secondary education at Trondheim Cathedral School in 1921, and graduated from the University of Oslo with the cand.real. degree in 1927. In his early career he published the work ''The 'Øst' Expedition to the Denmark Strait 1929'' in two volumes. The first volume, ''Hydrography'', was published together with J. T. Ruud in 1932. The second volume, ''The Phytoplankton and its Conditions of Growth'' came in 1935 and earned Braarud the dr.philos. degree. He had taken up planktology as a research assistant of Haaken Hasberg Gran at the botanical laboratory, a position he held from 1926 to 1933. From 1934 to 19 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erwin Kamptner
Erwin may refer to: People Given name * Erwin Chargaff (1905–2002), Austrian biochemist * Erwin Dold (1919–2012), German concentration camp commandant in World War 2 * Erwin Hauer (1926–2017), Austrian-born American sculptor * Egon Erwin Kisch (1885–1948), Czechoslovak writer and journalist * Erwin Emata (born 1973), Filipino mountain climber * Erwin James (born 1957), British writer and journalist * Erwin Klein (died 1992), American table tennis player * Erwin Koeman (born 1961), Dutch footballer and coach * Erwin Kramer (1902–1979), East German politician * Erwin Kreyszig (1922–2008), American academic * Erwin Neutzsky-Wulff (born 1949), Danish author and philosopher * Erwin Osen (1891–1970), Austrian mime artist * Erwin Panofsky (1892-1968), German-Jewish art historian * Erwin Ramírez (born 1971), Ecuadorian football player * Erwin Rommel (1891–1944), German field marshal of World War II * Erwin Rösener (1902–1946), German Nazi SS officer executed for war c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systematics
Biological systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: cladograms, phylogenetic trees, phylogenies). Phylogenies have two components: branching order (showing group relationships) and branch length (showing amount of evolution). Phylogenetic trees of species and higher taxa are used to study the evolution of traits (e.g., anatomical or molecular characteristics) and the distribution of organisms ( biogeography). Systematics, in other words, is used to understand the evolutionary history of life on Earth. The word systematics is derived from the Latin word ''systema,'' which means systematic arrangement of organisms. Carl Linnaeus used 'Systema Naturae' as the title of his book. Branches and applications In the study of biological systematics, researchers use the different branches to further understand the relations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phytoplankton
Phytoplankton () are the autotrophic (self-feeding) components of the plankton community and a key part of ocean and freshwater ecosystems. The name comes from the Greek words (), meaning 'plant', and (), meaning 'wanderer' or 'drifter'. Phytoplankton obtain their energy through photosynthesis, as do trees and other plants on land. This means phytoplankton must have light from the sun, so they live in the well-lit surface layers ( euphotic zone) of oceans and lakes. In comparison with terrestrial plants, phytoplankton are distributed over a larger surface area, are exposed to less seasonal variation and have markedly faster turnover rates than trees (days versus decades). As a result, phytoplankton respond rapidly on a global scale to climate variations. Phytoplankton form the base of marine and freshwater food webs and are key players in the global carbon cycle. They account for about half of global photosynthetic activity and at least half of the oxygen production, despi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algae
Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as '' Chlorella'', '' Prototheca'' and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to in length. Most are aquatic and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the '' Charophyta'', a division of green algae which includes, for example, '' Spirogyra'' and stoneworts. Algae that are carried by water are plankton, specifically phytoplankton. Algae constitute a polyphyletic group since they do not include a common ancestor, and although their plastids seem to have a single ori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Challenger Expedition
The ''Challenger'' expedition of 1872–1876 was a scientific program that made many discoveries to lay the foundation of oceanography. The expedition was named after the naval vessel that undertook the trip, . The expedition, initiated by William Benjamin Carpenter, was placed under the scientific supervision of Sir Charles Wyville Thomson—of the University of Edinburgh and Merchiston Castle School—assisted by five other scientists, including Sir John Murray, a secretary-artist and a photographer. The Royal Society of London obtained the use of ''Challenger'' from the Royal Navy and in 1872 modified the ship for scientific tasks, equipping it with separate laboratories for natural history and chemistry. The expedition, led by Captain George Nares, sailed from Portsmouth, England, on 21 December 1872. Other naval officers included Commander John Maclear. – pages 19 and 20 list the civilian staff and naval officers and crew, along with changes that took place duri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bathybius Haeckelii
''Bathybius haeckelii'' was a substance that British biologist Thomas Henry Huxley discovered and initially believed to be a form of primordial matter, a source of all organic life. He later admitted his mistake when it proved to be just the product of an inorganic chemical process (precipitation). In 1868 Huxley studied an old sample of mud from the Atlantic seafloor taken in 1857. When he first examined it, he had found only protozoan cells and placed the sample into a jar of alcohol to preserve it. Now he noticed that the sample contained an albuminous slime that appeared to be criss-crossed with veins. Huxley thought he had discovered a new organic substance and named it ''Bathybius haeckelii'', in honor of German biologist Ernst Haeckel. Haeckel had theorized about ''Urschleim'' ("primordial slime"), a protoplasm from which all life had originated. Huxley thought ''Bathybius'' could be that protoplasm, a missing link (in modern terms) between inorganic matter and organic lif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
