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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.
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 ...
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).
Directed evolution typically targets a particular gene for mutagenesis and then screens the resulting variants for a phenotype of interest, often independent of fitness effects, whereas adaptive laboratory evolution selects many genome-wide mutations that contribute to the fitness of actively growing cultures.
The investigational range of current research has widened to encompass the genetic architecture of adaptation, molecular evolution, ... point mutations vs. gene ...
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 ...
He argued that the deity supplies beneficial mutations to guide evolution. St George Jackson Mivart argued instead in his 1871 On the Genesis of Species that the deity, equipped with foreknowledge, sets the direction of evolution by specifying the (orthogenetic) laws that govern it, and leaves species to evolve according to the conditions they ...