Natural populations are seldom constant in size; these demographic changes can lead to interactions between selection and genetic drift that fall outside of equilibrium models. I study the patterns of genetic diversity that arise in populations of changing sizes, and the underlying allele frequency dynamics.
Selection does not act on individual alleles, but rather on allele combinations that are inherited together. I am interested in how correlations along the genome emerge due to this linkage. In our recent work with Zhiru Liu and Benjamin Good, we explored how allele correlations are shaped by selection, recombination, and genetic drift. We used our theoretical predictions to gain insight into the rates of horizontal gene transfer in bacterial populations.
In collaboration with the Winslow lab, I work on characterizing tumor growth rates across space and time using genetic barcoding.