Research

Research

I use theoretical population genetics (or, beanbag genetics) as a way to investigate some topics in evolutionary theory.

Sex-specific selection: In many species there are two sexes. These sexes may not experience the same selection pressures. I have been exploring the genetic consequences of these two simple facts on a number of fronts. I’m interested in a general sense about what happens to gene frequencies in a population under sexual antagonism. I’m also interested in the introgression of genes from one species into another in light of Haldane’s Rule, which is an extreme kind of sex-specific selection. I have also modeled the evolution of imprinted genes under male-limited selection, which is similar to selection in livestock populations.

Parent-of-origin-specific selection: As sure as sex-specific selection can exist in a population with two sexes, so too can parent-of-origin-specific selection exist. The optimal allele in one parent-of-origin context may not be the optimal allele in the other parent-of-origin context, creating parental antagonism. This is a relatively under-examined form of selection that can underlie the evolution of genomic imprinting and other hereditary phenomena. I am interested in the theoretical consequences of parent-of-origin-specific selection.

Sexual dimorphism for gene expression: I’ve taken an interest recently in sexually dimorphic gene expression. There is a wealth of data that shows that genes are expressed at different levels in the two sexes. I’m most interested in whether the data fits consistently with any theoretical predictions from sex-specific selection models. Additionally, sexually dimorphic gene expression will make heritability estimates differ in a parent-of-origin specific manner. I’m collaborating on a project that is attempting to discriminate between sex-specific gene expression and imprinted expression as a means to explain this parent-of-origin-specific result.

Sexual dimorphism and extinction: I’m currently at work on an empirical project in which I’m attempting to compare extinction rates between sexually dimorphic and sexually monomorphic species. I’m interested in the results of this for their own sake, but further, I’m interested to see if the things that matter to population geneticists are of any consequence to macroevolution.