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Prey Switching
Prey switching is frequency-dependent predation, where the predator preferentially consumes the most common type of prey. The phenomenon has also been described as apostatic selection, however the two terms are generally used to describe different parts of the same phenomenon. Apostatic selection has been used by authors looking at the differences between different genetic morphs. In comparison, prey switching has been used when describing the choice between different species.Allen, J.A. (1988) Frequency-dependent selection by predators. Philos. T. Roy. Soc. B 319, 485-503 Definition The term ''switching'' was first coined by the ecologist Murdoch in 1969 to describe the situation where a predator eats disproportionately more of the most common type of prey. Eight years earlier in 1962 the geneticst B. C. Clarke described a similar phenomenon and called it "apostatic selection". Since then the term ''prey switching'' has mainly been used by ecologists, while ''apostatic selection' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency Dependent Selection
Frequency-dependent selection is an evolutionary process by which the fitness of a phenotype or genotype depends on the phenotype or genotype composition of a given population. * In positive frequency-dependent selection, the fitness of a phenotype or genotype increases as it becomes more common. * In negative frequency-dependent selection, the fitness of a phenotype or genotype decreases as it becomes more common. This is an example of balancing selection. * More generally, frequency-dependent selection includes when biological interactions make an individual's fitness depend on the frequencies of other phenotypes or genotypes in the population. Frequency-dependent selection is usually the result of interactions between species (predation, parasitism, or competition), or between genotypes within species (usually competitive or symbiotic), and has been especially frequently discussed with relation to anti-predator adaptations. Frequency-dependent selection can lead to polymorphic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apostatic Selection
Apostatic selection is a form of negative frequency-dependent selection. It describes the survival of individual prey animals that are different (through mutation) from their species in a way that makes it more likely for them to be ignored by their predators. It operates on polymorphic species, species which have different forms. In apostatic selection, the common forms of a species are preyed on more than the rarer forms, giving the rare forms a selective advantage in the population. It has also been discussed that apostatic selection acts to stabilize prey polymorphisms. The term "apostatic selection" was introduced in 1962 by Bryan Clarke in reference to predation on polymorphic grove snails and since then it has been used as a synonym for negative frequency-dependent selection. The behavioural basis of apostatic selection was initially neglected, but was eventually established by A.B Bond. Apostatic selection can also apply to the predator if the predator has various morp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bryan Clarke
Bryan Campbell Clarke (24 June 1932 – 27 February 2014) was a British Professor of genetics, latterly emeritus at the University of Nottingham. Clarke is particularly noted for his work on apostatic selection (which is a term he coined in 1962) and other forms of frequency-dependent selection, and work on polymorphism in snails, much of it done during the 1960s. Later, he studied molecular evolution. He made the case for natural selection as an important factor in the maintenance of molecular variation, and in driving evolutionary changes in molecules through time. In doing so, he questioned the over-riding importance of random genetic drift advocated by King, Jukes, and Kimura. With Professor James J Murray Jnr (University of Virginia), he carried out an extensive series of studies on speciation in land snails of the genus '' Partula'' inhabiting the volcanic islands of the Eastern Pacific. These studies helped illuminate the genetic changes that take place during the o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preference
In psychology, economics and philosophy, preference is a technical term usually used in relation to choosing between alternatives. For example, someone prefers A over B if they would rather choose A than B. Preferences are central to decision theory because of this relation to behavior. Some methods such as Ordinal Priority Approach use preference relation for decision-making. As connative states, they are closely related to desires. The difference between the two is that desires are directed at one object while preferences concern a comparison between two alternatives, of which one is preferred to the other. In insolvency, the term is used to determine which outstanding obligation the insolvent party has to settle first. Psychology In psychology, preferences refer to an individual's attitude towards a set of objects, typically reflected in an explicit decision-making process (Lichtenstein & Slovic, 2006). The term is also used to mean evaluative judgment in the sense of liking ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inclusive Fitness
In evolutionary biology, inclusive fitness is one of two metrics of evolutionary success as defined by W. D. Hamilton in 1964: * Personal fitness is the number of offspring that an individual begets (regardless of who rescues/rears/supports them) * Inclusive fitness is the number of offspring equivalents that an individual rears, rescues or otherwise supports through its behaviour (regardless of who begets them) An individual's own child, who carries one half of the individual's genes, is defined as one offspring equivalent. A sibling's child, who will carry one-quarter of the individual's genes, is 1/2 offspring equivalent. Similarly, a cousin's child, who has 1/16 of the individual's genes, is 1/8 offspring equivalent. From the gene's point of view, evolutionary success ultimately depends on leaving behind the maximum number of copies of itself in the population. Prior to Hamilton's work, it was generally assumed that genes only achieved this through the number of viable off ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optimal Foraging Theory
Optimal foraging theory (OFT) is a behavioral ecology model that helps predict how an animal behaves when searching for food. Although obtaining food provides the animal with energy, searching for and capturing the food require both energy and time. To maximize fitness, an animal adopts a foraging strategy that provides the most benefit (energy) for the lowest cost, maximizing the net energy gained. OFT helps predict the best strategy that an animal can use to achieve this goal. OFT is an ecological application of the optimality model. This theory assumes that the most economically advantageous foraging pattern will be selected for in a species through natural selection. When using OFT to model foraging behavior, organisms are said to be maximizing a variable known as the currency, such as the most food per unit time. In addition, the constraints of the environment are other variables that must be considered. Constraints are defined as factors that can limit the forager's abili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecological Theory
Theoretical ecology is the scientific discipline devoted to the study of ecosystem, ecological systems using theoretical methods such as simple conceptual models, mathematical models, computer simulation, computational simulations, and advanced data analysis. Effective models improve understanding of the natural world by revealing how the dynamics of species populations are often based on fundamental biological conditions and processes. Further, the field aims to unify a diverse range of empirical observations by assuming that common, mechanistic processes generate observable phenomena across species and ecological environments. Based on biologically realistic assumptions, theoretical ecologists are able to uncover novel, non-intuitive insights about natural processes. Theoretical results are often verified by empirical and observational studies, revealing the power of theoretical methods in both predicting and understanding the noisy, diverse biological world. The field is broad a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guppy
The guppy (), also known as millionfish and rainbow fish, is one of the world's most widely distributed tropical fish and one of the most popular freshwater aquarium fish species. It is a member of the family Poeciliidae and, like almost all American members of the family, is live-bearing. Guppies originate from northeast South America, but have been introduced to many environments and are now found all over the world. They are highly adaptable and thrive in many different environmental and ecological conditions. Male guppies, which are smaller than females, have ornamental caudal and dorsal fins. Wild guppies generally feed on a variety of food sources, including benthic algae and aquatic insect larvae. Guppies are used as a model organism in the fields of ecology, evolution, and behavioural studies. Taxonomy Guppies were first described in Venezuela as ''Poecilia reticulata'' by Wilhelm Peters in 1859 and as ''Lebistes poecilioides'' in Barbados by De Filippi in 1861. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stoneflies
Plecoptera is an order of insects, commonly known as stoneflies. Some 3,500 species are described worldwide, with new species still being discovered. Stoneflies are found worldwide, except Antarctica. Stoneflies are believed to be one of the most primitive groups of Neoptera, with close relatives identified from the Carboniferous and Lower Permian geological periods, while true stoneflies are known from fossils only a bit younger. Their modern diversity, however, apparently is of Mesozoic origin. Plecoptera are found in both the Southern and Northern Hemispheres, and the populations are quite distinct, although the evolutionary evidence suggests species may have crossed the equator on a number of occasions before once again becoming geographically isolated. All species of Plecoptera are intolerant of water pollution, and their presence in a stream or still water is usually an indicator of good or excellent water quality. Description and ecology Stoneflies have a generaliz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bombus Pensylvanicus
''Bombus pensylvanicus'', the American bumblebee, is a threatened species of bumblebee native to North America. It occurs in eastern Canada, throughout much of the Eastern United States, and much of Mexico.Hatfield, R., et al. 2015''Bombus pensylvanicus''.The IUCN Red List of Threatened Species. Downloaded on 09 March 2016. Once the most prevalent bumblebee in the southern United States, populations of ''Bombus pensylvanicus'' have decreased significantly in recent years, including in its scientific namesake state of Pennsylvania where its numbers are considered critically low. Overall, the population has dropped nearly 90% in just the last 20 years. ''Bombus pensylvanicus'' tends to live and nest in open farmland and fields. It feeds on several food plants, favoring sunflowers and clovers, and functions as a pollinator. Taxonomy and phylogenetics ''Bombus pensylvanicus'' belongs to the order Hymenoptera (consisting of ants, wasps, bees, and sawflies), the family Apidae (consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Springer Science+Business Media
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing. Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in the 1990s and a sale to venture capitalists it fused with Wolters Kluwer and eventually became part of Springer Nature in 2015. Springer has major offices in Berlin, Heidelberg, Dordrecht, and New York City. History Julius Springer founded Springer-Verlag in Berlin in 1842 and his son Ferdinand Springer grew it from a small firm of 4 employees into Germany's then second largest academic publisher with 65 staff in 1872.Chronology ". Springer Science+Business Media. In 1964, Springer expanded its business internationally, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joy M
The word joy refers to the emotion evoked by well-being, success, or good fortune, and is typically associated with feelings of intense, long lasting happiness. Dictionary definitions Dictionary definitions of joy typically include a sense of it being a reaction to an external happening, e.g. a physical sensation experienced, or receiving good news. Distinction vs similar states saw a clear distinction between joy, pleasure, and happiness: "I sometimes wonder whether all pleasures are not substitutes for Joy", and "I call it Joy, which is here a technical term and must be sharply distinguished both from Happiness and Pleasure. Joy (in my sense) has indeed one characteristic, and one only, in common with them; the fact that anyone who has experienced it will want it again... I doubt whether anyone who has tasted it would ever, if both were in his power, exchange it for all the pleasures in the world. But then Joy is never in our power and Pleasure often is." Michela Summa sa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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