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arXiv · 2511.20483

$Λ$-Seed-Bank-Wright-Fisher process conditioned on fixation

María Clara Fittipaldi·Adrián González Casanova·Julio Ernesto Nava Trejo
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Abstract

We investigate the $Λ$-Seed-Bank-Wright-Fisher process, a model describing allele frequency dynamics in populations exhibiting both skewed offspring distributions and dormancy. By performing a change of measure, we condition this process on the eventual fixation of a specified genetic type. The resulting process is again a $Λ$-Wright-Fisher process with a seed bank, but now features coordinated mutations driven by a random switching environment. Our analysis relies on two key techniques: the lookdown construction and sampling duality. These tools provide a pathwise construction of the conditioned process while preserving a means to recover the conditioned population genealogy. The resulting genealogy corresponds to a structured $Λ$-coalescent with coordinated mutations determined by the switching environment.

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María Clara Fittipaldi, Adrián González Casanova, Julio Ernesto Nava Trejo. 2025-11-25. $Λ$-Seed-Bank-Wright-Fisher process conditioned on fixation. https://arxiv.org/abs/2511.20483

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