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The term natural selection is most often defined to operate on heritable traits, because these directly participate in evolution. However, natural selection is "blind" in the sense that changes in phenotype can give a reproductive advantage regardless of whether or not the trait is heritable.
A simplification of an allopatric speciation experiment where two lines of fruit flies are raised on maltose and starch media. Laboratory experiments of speciation have been conducted for all four modes of speciation: allopatric, peripatric, parapatric, and sympatric; and various other processes involving speciation: hybridization, reinforcement, founder effects, among others.
Other evolutionary forces outside of mutation and natural selection can also play a role or be incorporated into experimental evolution studies, such as genetic drift and gene flow. [ 3 ] The organism used is decided by the experimenter, based on the hypothesis to be tested.
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]
Natural selection – Mechanism of evolution by differential survival and reproduction of individuals Sexual selection – Mode of natural selection involving the choosing of and competition for mates; Mutation – Alteration in the nucleotide sequence of a genome; Gene flow – Transfer of genetic variation from one population to another
Their evolution is cited as an example of both natural and sexual selection. [ 40 ] [ 41 ] A 2008 study suggests that sympatric speciation has occurred in Tennessee cave salamanders . [ 42 ] Sympatric speciation driven by ecological factors may also account for the extraordinary diversity of crustaceans living in the depths of Siberia's Lake ...
For example, J.B.S. Haldane estimated in 1924 the rate of evolution by natural selection in the peppered moth in his first series of A Mathematical Theory of Natural and Artificial Selection. He estimated that for the peppered moth having reproductive cycle in a year, it would take 48 generations to produce the dominant (melanic or black) forms ...
Patrick Matthew (20 October 1790 – 8 June 1874) was a Scottish grain merchant, fruit farmer, forester, and landowner, who contributed to the understanding of horticulture, silviculture, and agriculture in general, with a focus on maintaining the British navy and feeding new colonies.