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Ant Mill
An ant mill is an observed phenomenon in which a group of army ants are separated from the main foraging party, lose the pheromone track and begin to follow one another, forming a continuously rotating circle, commonly known as a "death spiral" because the ants might eventually die of exhaustion. It has been reproduced in laboratories and has been produced in ant colony simulations. The phenomenon is a side effect of the self-organizing structure of ant colonies. Each ant follows the ant in front of it, which works until a slight deviation begins to occur, typically by an environmental trigger, and an ant mill forms. An ant mill was first described in 1921 by William Beebe, who observed a mill 1200 ft (~370 m) in circumference. It took each ant two and a half hours to make one revolution. Similar phenomena have been noted in processionary caterpillars and fish. See also * Information cascade * Feedback loop * Stigmergy * Woozle effect * The blind leading the blind * Rat ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ant Mill
An ant mill is an observed phenomenon in which a group of army ants are separated from the main foraging party, lose the pheromone track and begin to follow one another, forming a continuously rotating circle, commonly known as a "death spiral" because the ants might eventually die of exhaustion. It has been reproduced in laboratories and has been produced in ant colony simulations. The phenomenon is a side effect of the self-organizing structure of ant colonies. Each ant follows the ant in front of it, which works until a slight deviation begins to occur, typically by an environmental trigger, and an ant mill forms. An ant mill was first described in 1921 by William Beebe, who observed a mill 1200 ft (~370 m) in circumference. It took each ant two and a half hours to make one revolution. Similar phenomena have been noted in processionary caterpillars and fish. See also * Information cascade * Feedback loop * Stigmergy * Woozle effect * The blind leading the blind * Rat ki ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Army Ants
The name army ant (or legionary ant or ''marabunta'') is applied to over 200 ant species in different lineages. Because of their aggressive predatory foraging groups, known as "raids", a huge number of ants forage simultaneously over a limited area. Another shared feature is that, unlike most ant species, army ants do not construct permanent nests; an army ant colony moves almost incessantly over the time it exists. All species are members of the true ant family, Formicidae, but several groups have independently evolved the same basic behavioural and ecological syndrome. This syndrome is often referred to as "legionary behaviour", and may be an example of convergent evolution. Most New World army ants belong to the genera ''Cheliomyrmex'', '' Neivamyrmex'', '' Nomamyrmex'', '' Labidus'', and '' Eciton''. The largest genus is ''Neivamyrmex'', which contains more than 120 species; the most predominant species is ''Eciton burchellii''; its common name "army ant" is considered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are ''alarm signal, alarm pheromones'', ''food trail pheromones'', ''sex pheromones'', and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology. Background The portmanteau word "pheromone" was coined by Peter Karlson and Martin Lüscher in 1959, based on the Greek φερω ''pheroo'' ('I carry') and ὁρμων ''hormon'' ('stimulating'). P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fatigue (medical)
Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve after rest or sleep, or occurs independently of physical or mental exertion, it may be a symptom of a medical condition that may become severe or progressive. Fatigue can be a feature of a mental disorder such as depression; may be associated with conditions of chronic pain such as fibromyalgia; it may also feature in conditions of chronic low-level inflammation, and be a disease-related symptom in many other conditions. Fatigue often has no known cause, and is recognised as being very complex in nature. Fatigability describes a susceptibility to fatigue. Physical fatigue results from muscle fatigue brought about by intense physical activity. Mental fatigue results from prolonged periods of cognitive activity which impairs cognitive abil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-organizing
Self-organization, also called spontaneous order in the social sciences, is a process where some form of overall order arises from local interactions between parts of an initially disordered system. The process can be spontaneous when sufficient energy is available, not needing control by any external agent. It is often triggered by seemingly random fluctuations, amplified by positive feedback. The resulting organization is wholly decentralized, distributed over all the components of the system. As such, the organization is typically robust and able to survive or self-repair substantial perturbation. Chaos theory discusses self-organization in terms of islands of predictability in a sea of chaotic unpredictability. Self-organization occurs in many physical, chemical, biological, robotic, and cognitive systems. Examples of self-organization include crystallization, thermal convection of fluids, chemical oscillation, animal swarming, neural circuits, and black market ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ant Colony
An ant colony is a population of a single ant species capable to maintain its complete lifecycle. Ant colonies are eusocial, communal, and efficiently organized and are very much like those found in other social Hymenoptera, though the various groups of these developed sociality independently through convergent evolution. The typical colony consists of one or more egg-laying queens, numerous sterile females (workers, soldiers) and, seasonally, many winged sexual males and females. In order to establish new colonies, ants undertake flights that occur at species-characteristic times of the day. Swarms of the winged sexuals (known as alates) depart the nest in search of other nests. The males die shortly thereafter, along with most of the females. A small percentage of the females survive to initiate new nests. Names The term "ant colony" refers to a population of workers, reproductive individuals, and brood that live together, cooperate, and treat one another non-aggressively. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Beebe
Charles William Beebe ( ; July 29, 1877 – June 4, 1962) was an American naturalist, ornithologist, marine biologist, entomologist, explorer, and author. He is remembered for the numerous expeditions he conducted for the New York Zoological Society, his deep dives in the Bathysphere, and his prolific scientific writing for academic and popular audiences. Born in Brooklyn, New York and raised in East Orange, New Jersey, Beebe left college before obtaining a degree to work at the then newly opened New York Zoological Park, where he was given the duty of caring for the zoo's birds. He quickly distinguished himself in his work for the zoo, first with his skill in designing habitats for its bird population, and soon also with a series of research expeditions of increasing length, including an expedition around the world to document the world's pheasants. These expeditions formed the basis for a large quantity of writing for both popular and academic audiences, including an account ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thaumetopoeidae
Thaumetopoeinae is a subfamily of moths in the family Notodontidae. This group is sometimes treated as a family Thaumetopoeidae with three subfamilies: Thaumetopoeinae, Anaphinae and Epicominae. However, it is now commonly treated at subfamily rank based on morphological and molecular phylogenetic evidence. The etymology of the subfamily name derives from the two ancient greek words (), ''marvelous'', and (), ''to do'', and literally means ''showing beautiful things''. This explains why the name is sometimes spelled Thaumatopoeinae, incorrectly from the taxonomic standpoint, but in accordance with etymology. The larval stage of some Thaumetopoeinae are known as processionary caterpillars, so named because they move in columns in search of food, resembling a procession. Some of the species, like the pine and oak processionaries, can constitute a health hazard due to their urticating hairs. Genera and some species *'' Aglaosoma'' **''Aglaosoma variegata ''Aglaosoma variegat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Information Cascade
An Information cascade or informational cascade is a phenomenon described in behavioral economics and network theory in which a number of people make the same decision in a sequential fashion. It is similar to, but distinct from herd behavior. An information cascade is generally accepted as a two-step process. For a cascade to begin an individual must encounter a scenario with a decision, typically a binary one. Second, outside factors can influence this decision (typically, through the observation of actions and their outcomes of other individuals in similar scenarios). The two-step process of an informational cascade can be broken down into five basic components: # There is a decision to be made – for example; whether to adopt a new technology, wear a new style of clothing, eat in a new restaurant, or support a particular political position # A limited action space exists (e.g. an adopt/reject decision) # People make the decision sequentially, and each person can observe t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feedback Loop
Feedback occurs when outputs of a system are routed back as inputs as part of a chain of cause-and-effect that forms a circuit or loop. The system can then be said to ''feed back'' into itself. The notion of cause-and-effect has to be handled carefully when applied to feedback systems: History Self-regulating mechanisms have existed since antiquity, and the idea of feedback had started to enter economic theory in Britain by the 18th century, but it was not at that time recognized as a universal abstraction and so did not have a name. The first ever known artificial feedback device was a float valve, for maintaining water at a constant level, invented in 270 BC in Alexandria, Egypt. This device illustrated the principle of feedback: a low water level opens the valve, the rising water then provides feedback into the system, closing the valve when the required level is reached. This then reoccurs in a circular fashion as the water level fluctuates. Centrifugal governors were u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stigmergy
Stigmergy ( ) is a mechanism of indirect coordination, through the environment, between agents or actions. The principle is that the trace left in the environment by an individual action stimulates the performance of a succeeding action by the same or different agent. Agents that respond to traces in the environment receive positive fitness benefits, reinforcing the likelihood of these behaviors becoming fixed within a population over time. Stigmergy is a form of self-organization. It produces complex, seemingly intelligent structures, without need for any planning, control, or even direct communication between the agents. As such it supports efficient collaboration between extremely simple agents, who may lack memory or individual awareness of each other. History The term "stigmergy" was introduced by French biologist Pierre-Paul Grassé in 1959 to refer to termite behavior. He defined it as: "Stimulation of workers by the performance they have achieved." It is derived from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woozle Effect
The Woozle effect, also known as evidence by citation, occurs when a source is widely cited for a claim it does not adequately support, giving said claim undeserved credibility. If replication studies are not done and no one notices that a key claim was never well-supported in its original publication, faulty assumptions may affect further research. The Woozle effect is somewhat similar to circular reporting in journalism, where someone makes a questionable claim, a journalist unthinkingly accepts it and republishes it not realizing its dubious and unreliable origins, and other journalists and the public continue to repeat and duplicate the unsupported claim. Origin and definition A Woozle is an imaginary character in the A. A. Milne book ''Winnie-the-Pooh'', published in 1926. In chapter three, "In which Pooh and Piglet Go Hunting and Nearly Catch a Woozle", Winnie-the-Pooh and Piglet start following tracks left in snow believing they are the tracks of an imaginary animal ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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