Y supergene evolution

The evolution of heteromorphic sex chromosomes has inspired theoretical and empirical research for a long time, producing a canonical model that considers Y chromosomes as gene poor, mutation rich, and ultimately doomed for extinction.

However, recent empirical work has started to question the canonical model as insufficient to explain the diversity of evolutionary faiths of Y chromosomes.

Y chromosome forms a linked cluster of genes with male-limited effects, but what these are and how the Y supergenes can maintain functionality and adaptive variation are poorly understood.

Here, I propose to investigate Y chromosomes by combining life history variation with sex chromosome data in a highly amenable system of seed beetles.

Using comparative genomics approach, I will study how mating system and gene duplication and translocation rates affect how Y chromosomes retain and accrue genes.

We have recently discovered Y linked regulation of sexual size dimorphism (SSD) in Callosobruchus maculatus and I propose to investigate how SSD variation across phylogeny is associated with Y linked growth pathway evolution.

Third, I propose to study how Y polymorphism can be maintained using genetic crosses, experimental evolution and phenotypic assays, focusing on the roles of epistasis and negative frequency dependent selection.

These studies will improve our understanding of how Y chromosomes evolve across timescales, providing novel insights into a topic of broad evolutionary significance.