Refimprove date November 2008 Panmixia or panmixis means random mating . ref King C and Stanfield W.D. 1997. Dictionary of genetics . Oxford. Panmixia panmixis random mating as contrasted with assortative mating. ref ref Merriam Webster Medical Dictionary. Panmixia Random mating within a breeding population. ref A panmictic population is one where all individuals are potential partners. This assumes that there are no mating restrictions, neither Genetics genetic or behavioural , upon the population, and that therefore all recombination is possible. The Wahlund effect assumes that the overall population is panmictic. ref citation title Darwinism s Struggle for Survival Heredity and the Hypothesis of Natural Selection first1 Jean last1 Gayon first2 Matthew last2 Cobb publisher Cambridge University Press year 1998 ISBN 0521562503 pages 158 ref In genetics , random mating involves the mating of individuals regardless of any physical, genetic, or social preference. In other words, the mating between two organisms is not influenced by any environmental, hereditary, or social interaction. Hence, potential mates have an equal chance of being selected. Random mating is a factor assumed in the Hardy Weinberg principle and is distinct from lack of natural selection in viability selection for instance, selection occurs before mating. Description In simpler terms, it is the ability of individuals in a population to move about freely within their Habitat ecology habitat , possibly over a range of hundreds to thousands of miles, and thus breed with other members of the population that defines panmixia or panmicticism . To signify the importance of this, imagine several different finite populations ..., Sewall Wright proposed a factor of Panmixia P to include in the equations describing the gene frequencies in a population, and accounting for a population s tendency towards panmixia, while a factor ... populace de Panmixie fr Panmixie kk pl Panmiksja pt Panmixia ru simple Random ... more details
small initial populations that must have been viable, and panmixia in the early stages of speciation ... alleles &ndash is impossible to eliminate by panmixia. However, local conditions may result in an altered ... more details
The fixation index F sub ST sub is a measure of population differentiation, genetic distance , based on Polymorphism biology genetic polymorphism data, such as single nucleotide polymorphism s SNPs or Microsatellite genetics microsatellite s. It is a special case of F statistics , developed in the 1920s by Sewall Wright . Definition The fixation index, F sub ST sub , is simply a measure of the diversity of randomly chosen alleles within the same sub population relative to that found in the entire population. It is often expressed as the proportion of genetic diversity due to allele frequency differences among populations. ref Cite journal doi 10.1038 nrg2611 pmid 19687804 issn 1471 0056 volume 10 issue 9 pages 639 650 last Holsinger first Kent E. coauthors Bruce S. Weir title Genetics in geographically structured populations defining, estimating and interpreting FST journal Nat Rev Genet year 2009 unused data DUPLICATE DATA doi 10.1038 nrg2611 ref This comparison of genetic variability within and between populations is frequently used in the field of population genetics . The values range from 0 to 1. A zero value implies complete Panmixia panmixis that is, that the two populations are interbreeding freely. A value of one would imply the two populations are completely separate. Several definitions of F sub ST sub have been used, all measuring different but related quantities. A common definition is ref name Hudson1992 Cite journal last1 Hudson first1 RR. last2 Slatkin first2 M. last3 Maddison first3 WP. title Estimation of Levels of Gene Flow from DNA Sequence Data journal Genetics volume 132 issue 2 pages 583 9 month Oct year 1992 doi pmid 1427045 pmc 1205159 ref math F ST frac Pi text Between Pi text Within Pi text Between math where math Pi text Between math and math Pi text Within math represent the Nucleotide diversity average number of pairwise differences between two individuals sampled from different math Pi text Between math or the same math Pi text Within ... more details
multiple image direction vertical width 220 image1 Jaguar head shot.jpg caption1 Light morph jaguar typical image2 Black jaguar.jpg caption2 Dark morph or melanistic jaguar about 6 of the South American population Evolutionary biology Polymorphism ref Classical Greek Greek many, and form, figure, silhouette ref in biology occurs when two or more clearly different phenotypes exist in the same population of a species in other words, the occurrence of more than one form or morph . In order to be classified as such, morphs must occupy the same habitat at the same time and belong to a Panmixia panmictic population one with random mating . ref name Ford unk. E.B. Ford Ford E.B. 1965. Genetic polymorphism . Faber & Faber, London. ref Polymorphism is common in nature it is related to biodiversity , genetic variation and adaptation it usually functions to retain variety of form in a population living in a varied environment. ref name Dobzhansky 1970 Theodosius Dobzhansky Dobzhansky, Theodosius . 1970. Genetics of the Evolutionary Process . New York City New York Columbia University Press Columbia U. Pr. ref rp 126 The most common example is sexual dimorphism , which occurs in many organisms. Other examples are mimetic forms of butterflies see mimicry , and human hemoglobin and blood types . Polymorphism results from evolutionary processes, as does any aspect of a species. It is heritable and is modified by natural selection . In polyphenism , an individual s genetic make up allows for different morphs, and the switch mechanism that determines which morph is shown is environmental. In genetic polymorphism , the genetic make up determines the morph. Ants exhibit both types in a single population. ref name Clark 1976 cite journal last Clark first W. C. year 1976 title The Environment and the Genotype in Polymorphism journal Zoological Journal of the Linnaean Society volume 58 pages 255&ndash 262 doi 10.1111 j.1096 3642.1976.tb00831.x issue 3 ref ref name Ford 1975 Po ... more details
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