Английская Википедия:General selection model

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Шаблон:Short description Шаблон:More citations needed The general selection model (GSM) is a model of population genetics that describes how a population's allele frequencies will change when acted upon by natural selection.Шаблон:Better source

Equation

The General Selection Model applied to a single gene with two alleles (let's call them A1 and A2) is encapsulated by the equation:

<math>\Delta q=\frac{pq \big[q(W_2-W_1) + p(W_1 - W_0)\big ]}{\overline{W}}</math>

where:

<math>p</math> is the frequency of allele A1

<math>q</math> is the frequency of allele A2

<math>\Delta q</math> is the rate of evolutionary change of the frequency of allele A2

<math>W_0,W_1, W_2</math> are the relative fitnesses of homozygous A1, heterozygous (A1A2), and homozygous A2 genotypes respectively.

<math>\overline{W}</math> is the mean population relative fitness.

In words:

The product of the relative frequencies, <math>pq</math>, is a measure of the genetic variance. The quantity pq is maximized when there is an equal frequency of each gene, when <math>p=q</math>. In the GSM, the rate of change <math>\Delta Q</math> is proportional to the genetic variation.

The mean population fitness <math>\overline{W}</math> is a measure of the overall fitness of the population. In the GSM, the rate of change <math>\Delta Q</math> is inversely proportional to the mean fitness <math>\overline{W}</math>—i.e. when the population is maximally fit, no further change can occur.

The remainder of the equation, <math> \big[q(W_2-W_1) + p(W_1 - W_0)\big ]</math>, refers to the mean effect of an allele substitution. In essence, this term quantifies what effect genetic changes will have on fitness.

See also

• Darwinian fitness
• Hardy–Weinberg principle
• Population genetics