The number of equilibria in the diallelic Levene model with multiple demes

作者：Novak Sebastian^*

来源：Theoretical Population Biology, 2011, 79(3): 97-101.

DOI：10.1016/j.tpb.2010.12.002

• Selection
• Migration
• Population subdivision
• Geographical structure
• Levene model
• Equilibrium

The Levene model is the simplest mathematical model to describe the evolution of gene frequencies in spatially subdivided populations. It provides insight into how locally varying selection promotes a population's genetic diversity. Despite its simplicity, interesting problem; have remained unsolved even in the diallelic case.
In this paper we answer an open problem by establishing that for two alleles at one locus and J demes, up to 2J - 1 polymorphic equilibria may coexist. We first present a proof for the case of stable monomorphisms and then show that the result also holds for protected alleles. These findings allow us to prove that any odd number (up to 2J - 1) of equilibria is possible, before we extend the proof to even numbers. We conclude with some numerical results and show that for J > 2, the proportion of parameter space affording this maximum is extremely small.

• 出版日期2011-5