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Polygyny Threshold Model
The polygyny threshold model is an explanation of polygyny, the mating of one male of a species with more than one female. The model shows how females may gain a higher level of biological fitness by mating with a male who already has a mate. The female makes this choice despite other surrounding males because the choice male's genetics, territory, food supply, or other important characteristics are better than those of his competitors, even with two females on the territory. Graphical depiction The graphical depiction of the model presented in Gordon Orians' 1969 paper is often used to explain the concept. The graph shows two curves on a graph of biological fitness versus environmental quality. Environmental quality refers to the quality of the male's territory. The left curve, labeled monogamous, is the perceived biological fitness for a female entering into a monogamous relationship with a given male. The right curve, labeled bigamous, shows the fitness of the same female enter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Great Reed Warbler
The great reed warbler (''Acrocephalus arundinaceus'') is a Eurasian passerine in the genus '' Acrocephalus''. The genus name ''Acrocephalus'' is from Ancient Greek ''akros'', "highest", and ''kephale'', "head". It is possible that Naumann and Naumann thought ''akros'' meant "sharp-pointed". The specific ''arundinaceus'' is from Latin and means "like a reed", from ''arundo, arundinis'', "reed". It used to be placed in the Old World warbler assemblage, but is now recognized as part of the marsh and tree-warbler family (Acrocephalidae). Great reed warblers are medium-sized birds and are the largest of the European warblers. They breed throughout mainland Europe and the west Palearctic and migrate to sub-Saharan Africa in the winter. Great reed warblers favour reed beds as their habitat during breeding months, while living in reed beds, bush thickets, rice fields, and forest clearings during the winter. Great reed warblers exhibit relatively low sexual dimorphism, and both genders ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mating Systems
A mating system is a way in which a group is structured in relation to sexual behaviour. The precise meaning depends upon the context. With respect to animals, the term describes which males and females mate under which circumstances. Recognised systems include monogamy, polygamy (which includes polygyny, polyandry, and polygynandry), and promiscuity, all of which lead to different mate choice outcomes and thus these systems affect how sexual selection works in the species which practice them. In plants, the term refers to the degree and circumstances of outcrossing. In human sociobiology, the terms have been extended to encompass the formation of relationships such as marriage. In plants The primary mating systems in plants are outcrossing (cross-fertilisation), autogamy (self-fertilisation) and apomixis (asexual reproduction without fertilization, but only when arising by modification of sexual function). Mixed mating systems, in which plants use two or even all three mating s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Fidelity
Infidelity (synonyms include cheating, straying, adultery, being unfaithful, two-timing, or having an affair) is a violation of a couple's emotional and/or sexual exclusivity that commonly results in feelings of anger, sexual jealousy, and rivalry. What constitutes infidelity depends on expectations within the relationship. In marital relationships, exclusivity is commonly assumed. Infidelity can cause psychological damage, including feelings of rage and betrayal, low sexual and personal confidence, and even post-traumatic stress disorder. People of all genders can experience social consequences if their act of infidelity becomes public, but the form and extent of these consequences can depend on the gender of the unfaithful person. Incidence After the Kinsey Reports came out in the early 1950s, findings suggested that historically and cross-culturally, extramarital sex has been a matter of regulation more than sex before marriage. The Kinsey Reports found that around half of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Psychology
Evolutionary psychology is a theoretical approach in psychology that examines cognition and behavior from a modern evolutionary perspective. It seeks to identify human psychological adaptations with regards to the ancestral problems they evolved to solve. In this framework, psychological traits and mechanisms are either functional products of natural and sexual selection, non-adaptive by-products of other adaptive traits, or noise. Adaptationist thinking about physiological mechanisms, such as the heart, lungs, and the liver, is common in evolutionary biology. Evolutionary psychologists apply the same thinking in psychology, arguing that just as the heart evolved to pump blood, and the liver evolved to detoxify poisons, there is modularity of mind in that different psychological mechanisms evolved to solve different adaptive problems. These evolutionary psychologists argue that much of human behavior is the output of psychological adaptations that evolved to solve recurrent p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypergamy
Hypergamy (colloquially referred to as "marrying up") is a term used in social science for the act or practice of a person marrying a spouse of higher caste or social status than themselves. The antonym "hypogamy" refers to the inverse: marrying a person of lower social class or status (colloquially "marrying down"). Both terms were coined in the Indian subcontinent in the 19th century while translating classical Hindu law books, which used the Sanskrit terms ''anuloma'' and ''pratiloma'', respectively, for the two concepts. The term hypergyny is used to describe the overall practice of women marrying up, since the men would be marrying down. India In rural India, hypergamy is an opportunity to modernize. Marriages in rural India are increasingly examples of hypergamy. Farmers and other rural workers want their daughters to have access to city life, for with metropolitan connections comes better job opportunities, upper-class social circles, even better housing opportunities ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, recognising excellence in science, supporting outstanding science, providing scientific advice for policy, education and public engagement and fostering international and global co-operation. Founded on 28 November 1660, it was granted a royal charter by King Charles II as The Royal Society and is the oldest continuously existing scientific academy in the world. The society is governed by its Council, which is chaired by the Society's President, according to a set of statutes and standing orders. The members of Council and the President are elected from and by its Fellows, the basic members of the society, who are themselves elected by existing Fellows. , there are about 1,700 fellows, allowed to use the postnominal title FRS (Fellow of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Economic Inequality
There are wide varieties of economic inequality, most notably income inequality measured using the distribution of income (the amount of money people are paid) and wealth inequality measured using the distribution of wealth (the amount of wealth people own). Besides economic inequality between countries or states, there are important types of economic inequality between different groups of people. Important types of economic measurements focus on wealth, income, and consumption. There are many methods for measuring economic inequality, the Gini coefficient being a widely used one. Another type of measure is the Inequality-adjusted Human Development Index, which is a statistic composite index that takes inequality into account. Important concepts of equality include equity, equality of outcome, and equality of opportunity. Whereas globalization has reduced global inequality (between nations), it has increased inequality within nations. Income inequality between nations peak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dendrobates
''Dendrobates'' is a genus of poison dart frogs native to Central and South America. It once contained numerous species, but most originally placed in this genus have been split off into other genera such as ''Adelphobates'', ''Ameerega'', ''Andinobates'', ''Epipedobates'', ''Excidobates'', ''Oophaga'', ''Phyllobates'' and ''Ranitomeya'' (essentially all the brightly marked poison dart frogs; i.e. excluding the duller genera in the family like ''Colostethus'' and ''Hyloxalus ''Hyloxalus'' is a genus of poison dart frogs, family Dendrobatidae. The genus is distributed in Central and South America, from Panama south to Peru (along the Pacific coast), along with Venezuela, Colombia, and Ecuador. They also inhabit the ea ...''), leaving only five large to medium-sized species in the genus ''Dendrobates''. All the other genera used to be grouped in with ''Dendrobates'' because it was previously thought that all brightly colored poison dart frogs came from the same ancestor but this ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Troglodytes Aedon
The house wren (''Troglodytes aedon'') is a very small bird of the wren family, Troglodytidae. It occurs from Canada to southernmost South America, and is thus the most widely distributed native bird in the Americas. It occurs in most suburban areas in its range and it is the single most common wren. Its taxonomy is highly complex and some subspecies groups are often considered separate species. The name ''troglodytes'' means "hole dweller", and is a reference to bird's tendency to disappear into crevices when hunting insects or to seek shelter. Taxonomy The house wren was formally described in 1809 by the French ornithologist Louis Jean Pierre Vieillot under the current binomial name ''Troglodytes aedon''. The specific epithet is from the Ancient Greek ''aēdōn'' meaning "nightingale". The type locality was designated as New York City by Harry Oberholser in 1934. There are 32 recognised subspecies. These are sometimes divided into three distinct groups and one or several dist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red-winged Blackbird
The red-winged blackbird (''Agelaius phoeniceus'') is a passerine bird of the family Icteridae found in most of North America and much of Central America. It breeds from Alaska and Newfoundland south to Florida, the Gulf of Mexico, Mexico, and Guatemala, with isolated populations in western El Salvador, northwestern Honduras, and northwestern Costa Rica. It may winter as far north as Pennsylvania and British Columbia, but northern populations are generally migratory, moving south to Mexico and the southern United States. Claims have been made that it is the most abundant living land bird in North America, as bird-counting censuses of wintering red-winged blackbirds sometimes show that loose flocks can number in excess of a million birds per flock and the full number of breeding pairs across North and Central America may exceed 250 million in peak years. It also ranks among the best-studied wild bird species in the world. The red-winged blackbird is sexually dimorphic; the male i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polygyny
Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women. Incidence Polygyny is more widespread in Africa than in any other continent. Some scholars see the slave trade's impact on the male-to-female sex ratio as a key factor in the emergence and fortification of polygynous practices in regions of Africa. Polygyny is most common in a region known as the "polygamy belt" in West Africa and Central Africa, with the countries estimated to have the highest polygamy prevalence in the world being Burkina Faso, Mali, Gambia, Niger and Nigeria. In the region of sub-Saharan Africa, polygyny is common and deeply rooted in the culture, with 11% of the population of sub-Saharan Africa living in such marriages (25% of the Muslim population and 3% of the Christian population, as of 2019). Polygyny is especially widespread in West Africa, with the countries estimated to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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