Experimental evolution of Caenorhabditis elegans hermaphrodite germline development in response to different reproduction systems – ExpEvolGermline

Hermaphroditic organisms have served as key models to study the evolution of sex allocation. Despite extensive past research, the genetic and developmental mechanisms by which hermaphrodite sex allocation can evolve remain largely unknown. Specifically, the genetics of sex allocation in hermaphrodites of mostly selfing species are unknown, and while there is empirical evidence for relaxed sexual selection in predominantly selfing populations, it is far less clear that natural selection can determine the evolution of sex allocation in hermaphrodites. Here we propose, using experimental evolution in Caenorhabditis elegans, to address whether natural selection on hermaphrodite germline leads to quantitative changes in the allocation of developmental resources to self-spermatogenesis and oogenesis. We will test several hypotheses about natural selection using an integrative approach coupling 100 generations of experimental evolution under novel sex ratio conditions together with high resolution genome-wide association and population genetic analyses of the loci implicated in germline development. Characterizing the evolution of developmental mechanisms by natural selection is the central goal of evolutionary developmental biology. The proposed project will be among the first to accomplish this goal.