Pierangelo Lombardo - SISSA Trieste #
 Fixation time in a subdivided population with balancing selection #
We describe a population of individuals carrying one of the two possible 
variants of a gene (alleles). The population is subdivided into groups 
(demes) living on a fully connected graph, and individuals are allowed 
to migrate from one deme to another.
While the stochastic dynamics (genetic drift) of each deme tends to fix 
one allele and make it present in all individuals of the deme, a 
deterministic force favours rare alleles (balancing selection). We 
investigate the influence of population subdivision on the mean time 
required by the population to fix one of the two alleles: this fixation 
time shows an unexpected behaviour as a function of the migration rate, 
which we rationalized within our approach.