Mutation rate evolution in attine ants

ended

Germline mutation rate (GMR) is a key concept in all disciplines of biology, and particularly in evolutionary biology and the biomedical sciences. GMR varies both across and within species, but what drives this variation is unclear. Theories predict that GMR variation is shaped by environmental selection pressures, by effective population sizes, and by prevailing life-history traits (across species) and parental age at reproduction (within species). However, our understanding is extremely limited because within-species GMR variation has been investigated only to some extent in humans, and larger comparative genome-level datasets in other clades have not yet been pursued. I propose to start filling this gap by studying GMR in attine fungus-growing ants and a set of outgroup. non-attine ants. The attine ants, a ca. 55 MY old monophyletic lineage, are ideal for understanding GMR variation across and within species because their basic ecology is similar (obligate dependence of farmed fungi for food) but their life-histories diversified enormously from the base to the crown of their phylogenetic tree, which presently has 15 recognized genus-level branches and >230 species. Against a background dataset of ~20 high quality genomes, I propose to obtain genome-wide GMR estimates for 12 attine ants and 7 non-attine ants while controlling for confounders of phylogeny, colony size, life-span and effective population size. In addition, I will do an in-depth analysis of a single leafcutter ant species with long-lived queens and stored sperm of the same age, where I can also control for parental age. I will implement the MutANTs project at the Centre for Social Evolution in Copenhagen, an internationally renowned research hub for interdisciplinary omics research on ants, with Professors Guojie Zhang and Jacobus Jan Boomsma as joint hosts. I expect that in the two years available MutANTs will yield the first comparative data to predict GMRs across and within species.