The twolocus ancestral graph in a subdivided population: convergence as the number of demes grows in the island model
 Sabin Lessard,
 John Wakeley
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We study the ancestral recombination graph for a pair of sites in a geographically structured population. In particular, we consider the limiting behavior of the graph, under Wright’s island model, as the number of subpopulations, or demes, goes to infinity. After an instantaneous samplesize adjustment, the graph becomes identical to the twolocus graph in an unstructured population, but with a time scale that depends on the migration rate and the deme size. Interestingly, when migration is gametic, this rescaling of time increases the population mutation rate but does not affect the population recombination rate. We compare this to the case of a partiallyselfing population, in which both mutation and recombination depend on the selfing rate. Our result for gametic migration holds both for finitesized demes, and in the limit as the deme size goes to infinity. However, when migration occurs during the diploid phase of the life cycle and demes are finite in size, the population recombination rate does depend on the migration rate, in a way that is reminiscent of partial selfing. Simulations imply that convergence to a rescaled panmictic ancestral recombination graph occurs for any number of sites as the number of demes approaches infinity.
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 Title
 The twolocus ancestral graph in a subdivided population: convergence as the number of demes grows in the island model
 Journal

Journal of Mathematical Biology
Volume 48, Issue 3 , pp 275292
 Cover Date
 20040301
 DOI
 10.1007/s002850030230x
 Print ISSN
 03036812
 Online ISSN
 14321416
 Publisher
 SpringerVerlag
 Additional Links
 Keywords

 Coalescent
 Island model
 Migration
 Recombination
 Industry Sectors
 Authors

 Sabin Lessard ^{(1)}
 John Wakeley ^{(2)}
 Author Affiliations

 1. Département de mathématiques et de statistique, Université de Montréal
 2. Department of Organismic and Evolutionary Biology, Harvard University