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Adaptive mutation, also called directed mutation or directed mutagenesis is a controversial evolutionary theory. It posits that mutations, or genetic changes, are much less random and more purposeful than traditional evolution, implying that organisms can respond to environmental stresses by directing mutations to certain genes or areas of the genome.
However, it is possible that cultural evolution could actually increase genetic adaptation. Cultural evolution has vastly increased communication and contact between different populations, and this provides much greater opportunities for genetic admixture between the different populations (Hawks et al. 2007).
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]
Without mutation, the ultimate source of all genetic variation, there would be no genetic changes and no subsequent adaptation through evolution by natural selection. Genetic change occurs in a population when mutation increases or decreases in its initial frequency followed by random genetic drift, migration, recombination or natural selection ...
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.
In other words, the beginning of evolving a particular trait starts out with a primary adaptation toward a fit or specific role, followed by a primary exaptation (a new role is derived using the existing feature but may not be perfect for it), which in turn leads to the evolution of a secondary adaptation (the feature is improved by natural ...
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 ...
The sequence data makes it possible to pinpoint the site in a DNA sequence that a mutation/allele frequency change occurred to bring about adaptation. [10] [9] [2] The nature of the adaptation and functional follow up studies can shed insight into what effect the mutation/allele has on phenotype.