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A 2019 review by Svensson and David Berger concluded that "we find little support for mutation bias as an independent force in adaptive evolution, although it can interact with selection under conditions of small population size and when standing genetic variation is limited, entirely consistent with standard evolutionary theory."
Evolution is the change in the heritable characteristics of biological populations over successive generations. [1] [2] It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. [3]
The mechanisms of evolution focus mainly on mutation, genetic drift, gene flow, non-random mating, and natural selection. Mutation: Mutation [12] is a change in the DNA sequence inside a gene or a chromosome of an organism. Most mutations are deleterious, or neutral; i.e. they can neither harm nor benefit, but can also be beneficial sometimes.
Molecular evolution describes how inherited DNA and/or RNA change over evolutionary time, and the consequences of this for proteins and other components of cells and organisms. Molecular evolution is the basis of phylogenetic approaches to describing the tree of life. Molecular evolution overlaps with population genetics, especially on shorter ...
Evolution is a change in the frequency of alleles in a population over time. Mutations occur at random and in the Darwinian evolution model natural selection acts on the genetic variation in a population that has arisen through this mutation. [2] These mutations can be beneficial or deleterious and are selected for or against based on that factor.
The neutral theory allows for the possibility that most mutations are deleterious, but holds that because these are rapidly purged by natural selection, they do not make significant contributions to variation within and between species at the molecular level. Mutations that are not deleterious are assumed to be mostly neutral rather than ...
A coherent theory of neutral evolution was first proposed by Motoo Kimura in 1968 [9] and by King and Jukes independently in 1969. [10] Kimura initially focused on differences among species; King and Jukes focused on differences within species. Many molecular biologists and population geneticists also contributed to the development of the ...
[37] [38] That is, the spectrum of mutation may become very important, particularly mutation biases, predictable differences in the rates of occurrence for different types of mutations, because bias in the introduction of variation can impose biases on the course of evolution. [39] Mutation plays a key role in other classical and recent ...