Research

We work on questions of phenotypic and genomic evolution.


The big question behind our work is how the sexes evolve different phenotypes. Males and females often differ in their sex roles and are therefore under opposing selection pressures on many homologous traits. Responding to opposing sex-specific selection, however, is far from trivial, because males and females share almost the entirety of their genomes. The combination of divergent selection pressures and genetic coupling across the sexes sets the scene for adaptive conflicts between males and females, where 'sexually antagonistic' alleles that benefit one sex but harm the other can be favoured by selection. Moreover, the shared genetics of male and female traits implies that the resolution of this conflict and the evolution of sexual dimorphism, must rely on mechanisms that uncouple male and female phenotypes, such as sex-specific gene expression.


One of the aims of our work is to identify the genetic loci at which adaptive conflicts between the sexes play out. A large and growing body of quantitative genetic studies shows that sexual antagonism is widespread in populations of animals and plants, yet little is known about the loci at which antagonistic alleles segregate. We are in the process of addressing this question, using the fruitfly Drosophila melanogaster as a model. Having identified antagonistic loci, we also study the evolutionary dynamics of antagonism and its resolution across Drosophila species.


A parallel strand of research investigates the evolution of plastic genotypes more generally. Sexual dimorphism is conceptually similar to many other instances where genomes express different phenotypes in response to genetic or environmental cues. We are interested in the evolution of novel regulatory mechanisms that allow such plasticity. In collaboration with Jürg Bähler, we use an empirical system in fission yeast to investigate the speed and trajectory by which novel gene regulation evolves and how they depend on the interplay between the intensity and pattern of selection, the mutational input into regulatory variation and the genetic properties of the regulatory mechanisms.