title: Fixation properties of subdivided populations with balancing selection.
abstract: In subdivided populations, migration acts together with selection and genetic drift and determines their evolution. Building upon a recently proposed method, which hinges on the emergence of a time scale separation between local and global dynamics, we study the fixation properties of subdivided populations in the presence of balancing selection. The approximation implied by the method is accurate when the effective selection strength is small and the number of subpopulations is large. In particular, it predicts a phase transition between species coexistence and biodiversity loss in the infinite-size limit and, in finite populations, a nonmonotonic dependence of the mean fixation time on the migration rate. In order to investigate the fixation properties of the subdivided population for stronger selection, we introduce an effective coarser description of the dynamics in terms of a voter model with intermediate states, which highlights the basic mechanisms driving the evolutionary process.
authors: SISSA-International School for Advanced Studies and INFN, via Bonomea 265, 34136 Trieste, Italy.
authors: Pierangelo
authors: P
authors: Lombardo
authors: SISSA-International School for Advanced Studies and INFN, via Bonomea 265, 34136 Trieste, Italy.
authors: Andrea
authors: A
authors: Gambassi
authors: Department of Applied Science and Technology-DISAT, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy.|Collegio Carlo Alberto, Via Real Collegio 30, 10024 Moncalieri, Italy.
authors: Luca
authors: L
authors: Dall'Asta
mesh_terms: D019143:Evolution, Molecular; D040961:Genetic Drift; D005828:Genetics, Population; D008957:Models, Genetic; D012641:Selection, Genetic; D013997:Time Factors