An ant mill is an observed phenomenon in which a group of army ants, separated from the main foraging party, lose the pheromone track and begin to follow one another, forming a continuously rotating circle. This circle is commonly known as a "death spiral" because the ants might eventually die of exhaustion. It has been reproduced in laboratories and in ant colony simulations. [1]
The phenomenon is a side effect of the self-organizing structure of ant colonies. Each ant merely follows the ant in front of it, which functions until a slight deviation begins to occur, typically by an environmental trigger, and an ant mill forms. [2] An ant mill was first described in 1921 by William Beebe, who observed a mill 370 m in circumference. [3] It took each ant two and a half hours to make one revolution. [3] Similar phenomena have been noted in processionary caterpillars and fish. [4]
Ants are eusocial insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from vespoid wasp ancestors in the Cretaceous period. More than 13,800 of an estimated total of 22,000 species have been classified. They are easily identified by their geniculate (elbowed) antennae and the distinctive node-like structure that forms their slender waists.
Hymenoptera is a large order of insects, comprising the sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are parasitic. Females typically have a special ovipositor for inserting eggs into hosts or places that are otherwise inaccessible. This ovipositor is often modified into a stinger. The young develop through holometabolism —that is, they have a wormlike larval stage and an inactive pupal stage before they reach adulthood.
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 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.
In psychology and ethology, imprinting is any kind of phase-sensitive learning that is rapid and apparently independent of the consequences of behaviour. It was first used to describe situations in which an animal or person learns the characteristics of some stimulus, which is therefore said to be "imprinted" onto the subject. Imprinting is hypothesized to have a critical period.
Swarm behaviour, or swarming, is a collective behaviour exhibited by entities, particularly animals, of similar size which aggregate together, perhaps milling about the same spot or perhaps moving en masse or migrating in some direction. It is a highly interdisciplinary topic.
Wishful thinking is the formation of beliefs based on what might be pleasing to imagine, rather than on evidence, rationality, or reality. It is a product of resolving conflicts between belief and desire. Methodologies to examine wishful thinking are diverse. Various disciplines and schools of thought examine related mechanisms such as neural circuitry, human cognition and emotion, types of bias, procrastination, motivation, optimism, attention and environment. This concept has been examined as a fallacy. It is related to the concept of wishful seeing.
Observer bias is one of the types of detection bias and is defined as any kind of systematic divergence from accurate facts during observation and the recording of data and information in studies. The definition can be further expanded upon to include the systematic difference between what is observed due to variation in observers, and what the true value is.
Iconic memory is the visual sensory memory register pertaining to the visual domain and a fast-decaying store of visual information. It is a component of the visual memory system which also includes visual short-term memory (VSTM) and long-term memory (LTM). Iconic memory is described as a very brief, pre-categorical, high capacity memory store. It contributes to VSTM by providing a coherent representation of our entire visual perception for a very brief period of time. Iconic memory assists in accounting for phenomena such as change blindness and continuity of experience during saccades. Iconic memory is no longer thought of as a single entity but instead, is composed of at least two distinctive components. Classic experiments including Sperling's partial report paradigm as well as modern techniques continue to provide insight into the nature of this SM store.
A phosphene is the phenomenon of seeing light without light entering the eye. The word phosphene comes from the Greek words phos (light) and phainein. Phosphenes that are induced by movement or sound may be associated with optic neuritis.
Non-Mendelian inheritance is any pattern in which traits do not segregate in accordance with Mendel's laws. These laws describe the inheritance of traits linked to single genes on chromosomes in the nucleus. In Mendelian inheritance, each parent contributes one of two possible alleles for a trait. If the genotypes of both parents in a genetic cross are known, Mendel's laws can be used to determine the distribution of phenotypes expected for the population of offspring. There are several situations in which the proportions of phenotypes observed in the progeny do not match the predicted values.
Inattentional blindness or perceptual blindness occurs when an individual fails to perceive an unexpected stimulus in plain sight, purely as a result of a lack of attention rather than any vision defects or deficits. When it becomes impossible to attend to all the stimuli in a given situation, a temporary "blindness" effect can occur, as individuals fail to see unexpected but often salient objects or stimuli.
A decentralised system in systems theory is a system in which lower level components operate on local information to accomplish global goals. The global pattern of behaviour is an emergent property of dynamical mechanisms that act upon local components, such as indirect communication, rather than the result of a central ordering influence of a centralised system.
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.
Change blindness is a perceptual phenomenon that occurs when a change in a visual stimulus is introduced and the observer does not notice it. For example, observers often fail to notice major differences introduced into an image while it flickers off and on again. People's poor ability to detect changes has been argued to reflect fundamental limitations of human attention. Change blindness has become a highly researched topic and some have argued that it may have important practical implications in areas such as eyewitness testimony and distractions while driving.
Self-deprecation is the act of reprimanding oneself by belittling, undervaluing, disparaging oneself, or being excessively modest. It can be used as a way to make complaints, express modesty, invoke optimal reactions or add humour. It may also be used as a way for individuals to appear more likable and agreeable.
Herd behavior is the behavior of individuals in a group acting collectively without centralized direction. Herd behavior occurs in animals in herds, packs, bird flocks, fish schools and so on, as well as in humans. Voting, demonstrations, riots, general strikes, sporting events, religious gatherings, everyday decision-making, judgement and opinion-forming, are all forms of human-based herd behavior.
The bouba–kiki effect, kiki–bouba effect, or takete–malumaphenomenon is a non-arbitrary mental association between certain speech sounds and certain visual shapes. The most typical research finding is that people, when presented with nonsense words, tend to associate certain ones with a rounded shape and other ones with a spiky shape. Its discovery dates back to the 1920s, when psychologists documented experimental participants as connecting nonsense words to shapes in consistent ways. There is a strong general tendency towards the effect worldwide; it has been robustly confirmed across a majority of cultures and languages in which it has been researched, for example including among English-speaking American university students, Tamil speakers in India, speakers of certain languages with no writing system, young children, infants, and the congenitally blind. It has also been shown to occur with familiar names. The effect was investigated using fMRI in 2018. The bouba–kiki effect is one form of sound symbolism.
Symmetry breaking of escaping ants is a herd behavior phenomenon observed when ants are constrained to a cell with two equidistant exits and then sprayed with an insect repellent. The ants tend to crowd one door more while trying to escape, thereby decreasing evacuation efficiency.
Megaponera analis is the sole species of the genus Megaponera. They are a strictly termite-eating (termitophagous) ponerine ant species widely distributed in Sub-Saharan Africa and most commonly known for their column-like raiding formation when attacking termite feeding sites. Their sophisticated raiding behaviour gave them the common name Matabele ant after the Matabele tribe, fierce warriors who overwhelmed various other tribes during the 1800s. With some individuals reaching up to 25 millimetres (0.98 in) in length, M. analis is one of the world's largest ants.