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Fossil Resins
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of '' Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online before print. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Diversity
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, seashell, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in #Resin, amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Though the fossil record is incomplete, numerous studies have demonstrated that there is enough information available to give a good understanding of the pattern of diversification of life on Earth. In addition, the record can predict and fill gaps such as the discovery of ''Tiktaalik'' in the arctic of Canada. Paleontology includes the study of fossils: their age, method of formation, and evolutionary significance. Specimens are sometimes considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years to 4.1 billion years old. Early edition, published online bef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mindspark Interactive Network
Mindspark Interactive Network, Inc. was an operating business unit of IAC known for the development and marketing of entertainment and personal computing software, as well as mobile application development. Mindspark's mobile division acquired iOS application developer Apalon in 2014, which was known for popular entertainment applications such as Weather Live, Emoji Keypad, and Calculator Pro. Mindspark's home office was based in Yonkers, New York, with other offices located in Los Angeles, California; Oakland, California; New York, New York; and Bellevue, Washington, among others. Tim Allen and Eric Esterlis served as the co-presidents of Mindspark. Former Mindspark CEO Joey Levin is CEO of IAC. Although later versions of the tool bars offered are less intrusive, many, if not all, of Mindspark's programs and toolbars were commonly classified as potentially unwanted programs, which may be installed without the user's explicit knowledge or consent. Many of them exhibited ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequoia (genus)
''Sequoia'' is a genus of redwood coniferous trees in the subfamily Sequoioideae of the family Cupressaceae. The only extant species of the genus is '' Sequoia sempervirens'' in the Northern California coastal forests ecoregion of Northern California and Southwestern Oregon in the United States. The two other genera in the subfamily Sequoioideae, '' Sequoiadendron'' and '' Metasequoia'', are closely related to ''Sequoia''. It includes the tallest trees, as well as the heaviest, in the world. Several extinct species have been named from fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...s, including ''Sequoia affinis ''(Western North America) and ''Sequoia magnifica'' (petrified wood from the Yellowstone National Park area). Etymology The name ''Sequoia'' was first ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutionary history, evolution of dinosaurs is a subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya and their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, Evolution of birds, having evolved from earlier Theropoda, theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. Dinosaurs are varied from taxonomy (biology), taxonomic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micrometre
The micrometre (English in the Commonwealth of Nations, Commonwealth English as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American English), also commonly known by the non-SI term micron, is a unit of length in the International System of Units (SI) equalling (SI standard prefix "micro-" = ); that is, one millionth of a metre (or one thousandth of a millimetre, , or about ). The nearest smaller common SI Unit, SI unit is the nanometre, equivalent to one thousandth of a micrometre, one millionth of a millimetre or one billionth of a metre (). The micrometre is a common unit of measurement for wavelengths of infrared radiation as well as sizes of biological cell (biology), cells and bacteria, and for grading wool by the diameter of the fibres. The width of a single human hair ranges from approximately 20 to . Examples Between 1 μm and 10 μm: * 1–10 μm – length of a typical bacterium * 3–8 μm – width of str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonization
Carbonization or carbonisation is the conversion of organic matters like plants and dead animal remains into carbon through destructive distillation. Complexity in carbonization Carbonization is a pyrolytic reaction, therefore, is considered a complex process in which many reactions take place concurrently such as dehydrogenation, Condensation reaction, condensation, Transfer hydrogenation, hydrogen transfer and isomerization. Carbonization differs from Coal#Geology, coalification in that it occurs much faster, due to its reaction rate being faster by many orders of magnitude. For the final pyrolysis temperature, the amount of heat applied controls the degree of carbonization and the residual content of foreign elements. For example, at T ~ the carbon content of the residue exceeds a mass fraction of 90 wt.%, whereas at T ~ more than 99 wt.% carbon is found. Carbonization is often exothermic, which means that it could in principle be made self-sustaining and be used as a sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Authigenesis
Authigenesis is the process whereby a mineral or sedimentary rock deposit is generated where it is found or observed. Such deposits are described as authigenic. Authigenic sedimentary Mineral, minerals form during or after sedimentation by Precipitation (chemistry), precipitation or Recrystallization (geology), recrystallization as opposed to detrital minerals, which are weathered by water or wind and transported to the depositional location. Authigenic sediments are the main constituents of deep sea sedimentation, compared to shallow waters or land where detrital sediments are more common. Authigenesis process The authigenesis process is driven by particles of sediment that are not in thermodynamic equilibrium with the conditions surrounding it. This often occurs in the ocean where changing conditions due to biological processes is common. In water, changing oxygen content or changing saturation causes Precipitation (chemistry), precipitation of minerals into the sediments, chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permineralization
Permineralization is a process of fossilization of bones and tissues in which mineral deposits form internal Casting, casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of plants. Process Permineralization, a type of fossilization, involves deposits of minerals within the cells of organisms. Water from the ground, lakes, or oceans seeps into the pores of organic tissue and forms a crystal cast with deposited minerals. Crystals begin to form in the porous cell walls. This process continues on the inner surface of the walls until the central cavity of the cell, the Lumen (anatomy), lumen, is completely filled. The cell walls themselves remain intact surrounding the crystals. Silicification In silicification, the weathering of rocks releases silicate minerals and the silica makes its way into a body of still ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absolute Dating
Absolute dating is the process of determining an age on a specified chronology in archaeology and geology. Some scientists prefer the terms chronometric or calendar dating, as use of the word "absolute" implies an unwarranted certainty of accuracy. Absolute dating provides a numerical age or range, in contrast with relative dating, which places events in order without any measure of the age between events. In archaeology, absolute dating is usually based on the physical, chemical, and life properties of the materials of artifacts, buildings, or other items that have been modified by humans and by historical associations with materials with known dates (such as coins and historical records). For example, coins found in excavations may have their production date written on them, or there may be written records describing the coin and when it was used, allowing the site to be associated with a particular calendar year. Absolute dating techniques include radiocarbon dating of wood o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiometric Dating
Radiometric dating, radioactive dating or radioisotope dating is a technique which is used to Chronological dating, date materials such as Rock (geology), rocks or carbon, in which trace radioactive impurity, impurities were selectively incorporated when they were formed. The method compares the abundance of a naturally occurring Radionuclide, radioactive isotope within the material to the abundance of its Radioactive decay, decay products, which form at a known constant rate of decay. Radiometric dating of minerals and rocks was pioneered by Ernest Rutherford (1906) and Bertram Boltwood (1907). Radiometric dating is now the principal source of information about the Absolute dating, absolute age of rocks and other Geology, geological features, including the age of Paleontology, fossilized life forms or the age of Earth itself, and can also be used to date a wide range of natural and Artifact (archaeology), man-made materials. Together with stratigraphy, stratigraphic principles, ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Dating
Relative dating is the science of determining the relative order of past events (i.e., the age of an object in comparison to another), without necessarily determining their absolute age (i.e., estimated age). In geology, rock or superficial deposits, fossils and lithologies can be used to correlate one stratigraphic column with another. Prior to the discovery of radiometric dating in the early 20th century, which provided a means of absolute dating, archaeologists and geologists used relative dating to determine ages of materials. Though relative dating can only determine the ''sequential order'' in which a series of events occurred, not ''when'' they occurred, it remains a useful technique. Relative dating by biostratigraphy is the preferred method in paleontology and is, in some respects, more accurate. The Law of Superposition, which states that older layers will be deeper in a site than more recent layers, was the summary outcome of 'relative dating' as observed in g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
