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dc.creatorVALENZUELA,CARLOS Y.
dc.date2000-01-01
dc.date.accessioned2019-05-02T21:20:59Z
dc.date.available2019-05-02T21:20:59Z
dc.identifierhttps://scielo.conicyt.cl/scielo.php?script=sci_arttext&pid=S0716-97602000000300004
dc.identifier.urihttp://revistaschilenas.uchile.cl/handle/2250/81338
dc.descriptionNeutral evolution results from random recurrent mutation and genetic drift. A small part of random evolution, that which is related to protein or DNA polymorphisms, is the subject of the Neutral Theory of Evolution. One of the foundations of this theory is the demonstration that the mutation rate (m) is equal to the substitution rate. Since both rates are independent of population size, they are independent of drift, which is dependent upon population size. Neutralists have erroneously equated the substitution rate with the fixation rate, despite the fact that they are antithetical conceptions. The neutralists then applied the random walk stochastic model to justify alleles or bases that were fixated or eliminated. In this model, once the allele or base frequencies reach the monomorphic states (values of 1.0 or 0.0), the absorbing barriers, they can no longer return to the polymorphic state. This operates in a pure mathematical model. If recurrent mutation occurs (as in biotic real systems) fixation and elimination are impossible. A population of bacteria in which m=10-8 base mutation (or substitution)/site/generation and the reproduction rate is 1000 cell cycle/year should replace all its genome bases in approximately 100,000 years. The expected situation for all sites is polymorphism for the four bases rather than monomorphism at 1.0 or 0.0 frequencies. If fixation and elimination of a base for more than 500,000 years are impossible, then most of the neutral theory is untenable. A new complete neutral model, which allows for recurrent substitutions, is proposed here based on recurrent mutation or substitution and drift alone. The model fits a binomial or Poisson distribution and not a geometric one, as does neutral theory.
dc.formattext/html
dc.languageen
dc.publisherSociedad de Biología de Chile
dc.relation10.4067/S0716-97602000000300004
dc.rightsinfo:eu-repo/semantics/openAccess
dc.sourceBiological Research v.33 n.3-4 2000
dc.subjectneutral evolution
dc.subjectneutral theory
dc.subjectmisconceptions
dc.subjectbases fixation
dc.subjectelimination
dc.titleMisconceptions and false expectations in neutral evolution


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