RT Journal Article
SR Electronic
T1 Limits to Genomic Divergence Under Sexually Antagonistic Selection
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 591610
DO 10.1101/591610
A1 Katja R. Kasimatis
A1 Peter L. Ralph
A1 Patrick C. Phillips
YR 2019
UL http://biorxiv.org/content/early/2019/03/28/591610.abstract
AB Since the autosomal genome is shared between the sexes, sex-specific fitness optima present an evolutionary challenge. While sexually antagonistic selection might favor different alleles within males and females, segregation randomly reassorts alleles at autosomal loci between sexes each generation. This process of homogenization during transmission thus prevents between-sex allelic divergence generated by sexually antagonistic selection from accumulating across multiple generations. However, recent empirical studies have reported high male-female FST statistics. Here, we use a population genetic model to evaluate whether these observations could plausibly be produced by sexually antagonistic selection. To do this, we use both a single-locus model with nonrandom mate choice, and individual-based simulations to study the relationship between strength of selection, degree of between-sex divergence, and the associated genetic load. We show that selection must be exceptionally strong to create measurable divergence between the sexes and that the decrease in population fitness due to this process is correspondingly high. Individual-based simulations with selection genome-wide recapitulate these patterns and indicate that small sample sizes and sampling variance can easily generate substantial male-female divergence. We therefore conclude that caution should be taken when interpreting autosomal allelic divergence between the sexes.