Comparative insights

Do Parasites and Mating Systems Jointly Shape Immune Gene Diversity in mammals?

To understand how immune genes evolve across different animals, I look at patterns on a broad, evolutionary scale. By combining data on life history traits, parasites, and genetics, I compare species to see what forces drive immune gene diversity. In one of the first studies of its kind, I found that while parasites do influence immune genes, sexual selection—like competition for mates or mate choice—may have an even stronger and more consistent impact across mammals.

Demographic history and gene duplication shape immune gene diversity in rodents

MHC genes are critical for pathogen defense, but it remains unclear how demographic instability influences their diversity. While balancing selection is often assumed to maintain MHC polymorphism, frequent population bottlenecks could erode this variation. To test this, I conducted a phylogenetically controlled comparative analysis across 16 rodent species with different demographic histories and levels of MHC gene duplication. I found that species with consistent bottlenecks had lower MHC allelic richness, while those with more duplicated MHC loci exhibited higher allelic diversity and stronger purifying selection. This study highlights the importance of demographic and genomic context in shaping immune gene evolution.