@article {Hether057513, author = {Tyler D. Hether}, title = {Uplift and erosion of genomic islands with standing genetic variation}, elocation-id = {057513}, year = {2016}, doi = {10.1101/057513}, publisher = {Cold Spring Harbor Laboratory}, abstract = {Details of the processes that generate biological diversity have long been of interest to evolutionary biologists. A common theme in nature is diversification via divergent selection with gene flow. Empirical studies on this topic find variable genetic differentiation throughout the genome, that genetic differentiation is non-randomly distributed, and that loci of adaptive significance are often found clustered together within {\textquotedblleft}genomic islands of divergence{\textquotedblright}. Theoretical models based on new mutations show how these genomic islands can arise and grow as a result of a complex interaction of various evolutionary and genic processes. In the current study, I ask if such genomic islands can alternatively arise from divergent selection from standing genetic variation and I tested this using a simple two locus model of selection. There are numerous ways in which standing genetic variation can be partitioned (e.g., between alleles, between loci, and between populations) and I tested which of these scenarios can give rise to an island pattern compared to no genomic differentiation or complete genomic differentiation. I found that divergent selection, even without reciprocal gene exchange between populations, following a bout of admixture can relatively quickly produce an island pattern. Moreover, I found two pathways in which islands can form from divergence from standing variation: 1) through the build up of islands and 2) through the breakdown of larger, genome-wide differentiation. Lastly, similar to new mutation theory, I found that the frequency of recombination is an important determinant of island formation from standing genetic variation such that mating behavior of a species (e.g., facultative or obligate sexual) can impact the likelihood of island formation.}, URL = {https://www.biorxiv.org/content/early/2016/06/09/057513}, eprint = {https://www.biorxiv.org/content/early/2016/06/09/057513.full.pdf}, journal = {bioRxiv} }