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Ballooning (spider)
Ballooning, sometimes called kiting, is a process by which spiders, and some other small invertebrates, move through the air by releasing one or more gossamer threads to catch the wind, causing them to become airborne at the mercy of air currents and electric fields. A 2018 study concluded that electric fields provide enough force to lift spiders in the air, and possibly elicit ballooning behavior. This is primarily used by spiderlings to disperse; however, larger individuals have been observed doing so as well. The spider climbs to a high point and takes a stance with its abdomen to the sky, releasing fine silk threads from its spinneret until it becomes aloft. Journeys achieved vary from a few metres to hundreds of kilometres. Even atmospheric samples collected from balloons at five kilometres altitude and ships mid-ocean have reported spider landings. Ballooning can be dangerous (due to predators, and due to the unpredictable nature of long-distance ballooning, which may brin ...
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Ballooning Spiderlings
Ballooning may refer to: * Hot air ballooning * Balloon (aeronautics) * Ballooning (spider) * Ballooning degeneration, a disease * Memory ballooning See also * Balloon (other) A balloon is a flexible container for (partially or fully) confining a gas. Balloon may also refer to: Arts, entertainment, and media Films * ''Balloon'' (2017 film), a Tamil film by Sinish starring Jai, Anjali, and Janani Iyer * ''Balloon'' (201 ... {{Disambiguation ...
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The Atlantic
''The Atlantic'' is an American magazine and multi-platform publisher. It features articles in the fields of politics, foreign affairs, business and the economy, culture and the arts, technology, and science. It was founded in 1857 in Boston, as ''The Atlantic Monthly'', a literary and cultural magazine that published leading writers' commentary on education, the abolition of slavery, and other major political issues of that time. Its founders included Francis H. Underwood and prominent writers Ralph Waldo Emerson, Oliver Wendell Holmes Sr., Henry Wadsworth Longfellow, Harriet Beecher Stowe, and John Greenleaf Whittier. James Russell Lowell was its first editor. In addition, ''The Atlantic Monthly Almanac'' was an annual almanac published for ''Atlantic Monthly'' readers during the 19th and 20th centuries. A change of name was not officially announced when the format first changed from a strict monthly (appearing 12 times a year) to a slightly lower frequency. It was a mo ...
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Caterpillar
Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder Symphyta) are commonly called caterpillars as well. Both lepidopteran and symphytan larvae have eruciform body shapes. Caterpillars of most species eat plant material ( often leaves), but not all; some (about 1%) eat insects, and some are even cannibalistic. Some feed on other animal products. For example, clothes moths feed on wool, and horn moths feed on the hooves and horns of dead ungulates. Caterpillars are typically voracious feeders and many of them are among the most serious of agricultural pests. In fact, many moth species are best known in their caterpillar stages because of the damage they cause to fruits and other agricultural produce, whereas the moths are obscure and do no direct harm. Conversely, various species of caterpi ...
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Mite
Mites are small arachnids (eight-legged arthropods). Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari, but genetic analysis does not show clear evidence of a close relationship. Most mites are tiny, less than in length, and have a simple, unsegmented body plan. The small size of most species makes them easily overlooked; some species live in water, many live in soil as decomposers, others live on plants, sometimes creating galls, while others again are Predation, predators or Parasitism, parasites. This last type includes the commercially destructive ''Varroa'' parasite of honey bees, as well as scabies mites of humans. Most species are harmless to humans, but a few are associated with allergies or may transmit diseases. The scientific discipline devoted to the study of mites is called acarology. Evolution and taxonomy The mites are not a defined taxon, but is used for two disti ...
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Upper Atmosphere
Upper atmosphere is a collective term that refers to various layers of the atmosphere of the Earth above the troposphere and corresponding regions of the atmospheres of other planets, and includes: * The mesosphere, which on Earth lies between the altitudes of about , sometimes considered part of the "middle atmosphere" rather than the upper atmosphere * The thermosphere, which on Earth lies between the altitudes of about * The exosphere, which on Earth lies between the altitudes of about and * The ionosphere, an ionized portion of the upper atmosphere which includes the upper mesosphere, thermosphere, and lower exosphere and on Earth lies between the altitudes of See also *Geospace Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies. Outer space is not completely empty—it is a near-perfect vacuum containing a low density of particles, pred ... * Magnetosphere References {{Reflist Atmos ...
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Drag (physics)
In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers (or surfaces) or between a fluid and a solid surface. Unlike other resistive forces, such as dry friction, which are nearly independent of velocity, the drag force depends on velocity. Drag force is proportional to the velocity for low-speed flow and the squared velocity for high speed flow, where the distinction between low and high speed is measured by the Reynolds number. Even though the ultimate cause of drag is viscous friction, turbulent drag is independent of viscosity. Drag forces always tend to decrease fluid velocity relative to the solid object in the fluid's path. Examples Examples of drag include the component of the net aerodynamic or hydrodynamic force acting opposite to the di ...
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Convection
Convection is single or multiphase fluid flow that occurs spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When the cause of the convection is unspecified, convection due to the effects of thermal expansion and buoyancy can be assumed. Convection may also take place in soft solids or mixtures where particles can flow. Convective flow may be transient (such as when a multiphase mixture of oil and water separates) or steady state (see Convection cell). The convection may be due to gravitational, electromagnetic or fictitious body forces. Heat transfer by natural convection plays a role in the structure of Earth's atmosphere, its oceans, and its mantle. Discrete convective cells in the atmosphere can be identified by clouds, with stronger convection resulting in thunderstorms. Natural convection also plays a role in stellar physics. Convection is often categorised or d ...
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Jet Stream
Jet streams are fast flowing, narrow, meandering thermal wind, air currents in the Atmosphere of Earth, atmospheres of some planets, including Earth. On Earth, the main jet streams are located near the altitude of the tropopause and are westerly winds (flowing west to east). Jet streams may start, stop, split into two or more parts, combine into one stream, or flow in various directions including opposite to the direction of the remainder of the jet. Overview The strongest jet streams are the polar jets around the Polar vortex, polar vortices, at above sea level, and the higher altitude and somewhat weaker subtropical jets at . The Northern Hemisphere and the Southern Hemisphere each have a polar jet and a subtropical jet. The northern hemisphere polar jet flows over the middle to northern latitudes of North America, Europe, and Asia and their intervening oceans, while the southern hemisphere polar jet mostly circles Antarctica, both all year round. Jet streams are the prod ...
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Threads Of Silk Following A Mass Spider Ballooning
Thread may refer to: Objects * Thread (yarn), a kind of thin yarn used for sewing ** Thread (unit of measurement), a cotton yarn measure * Screw thread, a helical ridge on a cylindrical fastener Arts and entertainment * ''Thread'' (film), 2016 Greek film * ''Threads'' (1932 film), a film directed by G. B. Samuelson * ''Threads'' (1984 film), a 1984 BBC television movie about a nuclear attack * ''Threads'' (2017 film), a Norwegian-Canadian animated short film * "Threads" (''Stargate SG-1''), a 2005 Stargate SG-1 episode * "Thread", a poem by Patti Smith from '' Babel'' * Thread, a lethal spore in the Dragonriders of Pern universe * ''Phantom Thread'', 2017 American historical drama film * '' Project Runway: Threads'', a Project Runway spin-off with child contestants Music * ''Threads'' (Battlefield Band album), 1995 * ''Threads'' (David S. Ware album), 2003 * ''Threads'' (Now, Now album), 2012 * ''Threads'' (Temposhark album), 2010 * ''Threads'' (Sheryl Crow album), 201 ...
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Pardosa Spp
''Pardosa'' is a large genus of wolf spiders, commonly known as the thin-legged wolf spiders. It was first described by C. L. Koch, in 1847, with more than 500 described species that are found in all regions of the world. Description THey are small to medium size wolf spiders, with clear and median and lateral bands on the carapace. They have relatively long legs with long spines on the foot. Which can be used to quickly identify some species. Species this genus contains 534 species: * '' Pardosa abagensis'' Ovtsharenko, 1979 – Russia, Abkhazia * ''Pardosa aciculifera'' Chen, Song & Li, 2001 – China * ''Pardosa acorensis'' Simon, 1883 – Azores * ''Pardosa adustella'' (Roewer, 1951) – Russia, Mongolia, China * '' Pardosa aenigmatica'' Tongiorgi, 1966 – Italy, Turkey, Azerbaijan * '' Pardosa afflicta'' (Holmberg, 1876) – Argentina * '' Pardosa agrestis'' ( Westring, 1861) – Palearctic * '' Pardosa agricola'' (Thorell, 1856) – Europe to Kazakhstan * ''Pardosa a ...
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Thermal
A thermal column (or thermal) is a rising mass of buoyant air, a convective current in the atmosphere, that transfers heat energy vertically. Thermals are created by the uneven heating of Earth's surface from solar radiation, and are an example of convection, specifically atmospheric convection. Thermals on Earth The Sun warms the ground, which in turn warms the air directly above. The warm air near the surface expands, becoming less dense than the surrounding air. The lighter air rises and cools due to its expansion in the lower pressure at higher altitudes. It stops rising when it has cooled to the same temperature, thus density, as the surrounding air. Associated with a thermal is a downward flow surrounding the thermal column. The downward-moving exterior is caused by colder air being displaced at the top of the thermal. The size and strength of thermals are influenced by the properties of the lower atmosphere (the ''troposphere''). When the air is cold, bubbles of warm ...
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Stegodyphus
''Stegodyphus'' is a genus of velvet spiders that was first described by Eugène Simon in 1873. They are distributed from Africa to Europe and Asia, with one species (''S. manaus'') found in Brazil. The name is derived from Ancient Greek ('' stegos''), meaning "covered". At least three species are social spiders, and several are known to use ballooning as a method of dispersal. Species it contains twenty species: *''Stegodyphus africanus'' ( Blackwall, 1866) – Africa *''Stegodyphus bicolor'' ( O. Pickard-Cambridge, 1869) – Southern Africa *'' Stegodyphus dufouri'' ( Audouin, 1826) – North, West Africa *''Stegodyphus dumicola'' Pocock, 1898 – Central, Southern Africa *''Stegodyphus hildebrandti ''Stegodyphus'' is a genus of velvet spiders that was first described by Eugène Simon in 1873. They are distributed from Africa to Europe and Asia, with one species (''S. manaus'') found in Brazil. The name is derived from Ancient Greek ( ...'' (Ferdinand Karsch, Kars ...
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