Our lab studies a variety of questions in evolutionary genetics using Drosophila as a model system. We combine classical, molecular, and population genetics to study the genetics of speciation, the interaction of recombination and natural selection, and the evolutionary dynamics of the selfish meiotic drive gene complex, Segregation Distorter.
We study the genetics of postzygotic reproductive isolation--the sterility and inviability of species hybrids. Our work on the evolution of hybrid sterility and inviability takes advantage of the genetic and genomic resources of D. melanogaster and its sister species, D. simulans, D. sechellia, and D. mauritiana to map, identify, and characterize the 'speciation genes' that cause hybrid fitness problems.
We also determine the causes of the strong evolutionary rules that characterize the evolution of hybrid sterility and inviability, like Haldane's rule and the large X-effect.
Recombination and adaptation
We study the interaction of natural selection and recombination in two ways. First, we use population genetics to test the considerable body of theory that predicts that genetic linkage constrains adaptation. Second, we are now studying the genetic basis of the evolutionary divergence of local recombination rates among closely related Drosophila species.
The Segregation Distorter (SD) system of Drosophila melanogaster is a classic selfish gene complex. The multiple, linked, epistatically interacting loci of the SD complex function together to gain a transmission advantage from heterozygous males by, in effect, killing rival sperm that bare homologous chromosomes. We are now studying the evolutionary dynamics of SD in natural populations and inferring the timing and geography of its origins.