# Stochastic Diploid Model for Gene Frequency in a Population

Stochastic Diploid Model for Gene Frequency in a Population

Imagine a single gene with two alleles and , where the frequency of the allele in the gene pool of an entire population is . Assume that this is a large and isolated population, that there is random mating, and that the fitness parameter varies stochastically through the generations. One can then predict the frequency of the allele in the population after generations.

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This Demonstration gives the time series of and lets you vary the fitness parameter and the stochastic noise . By moving the sliders, you can see that for a fixed there is a critical value of beyond which polymorphism (the existence of two or more different phenotypes in the population) occurs as a result of stochastic resonance. The dynamics does not depend on the initial condition .

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