Evidence for Variation in the Genetic Basis of Sex Determination in Brook Stickleback ().

The genetic basis of sex determination is typically conserved within species if not within broader lineages. For example, within the stickleback family (Gasterosteidae), has been identified as a master sex-determination (MSD) gene in multiple species across two genera. By contrast, the existence of within-species variability in the genetic basis of sex determination is not frequently observed but provides an opportunity to understand the evolution and turnover of sex determination systems.