Our research reveals the principles and processes that determine the nature, amount, distribution, and functional significance of genetic variation within and between natural populations and among related species. We draw on the tools of experimental and theoretical population genetics, molecular evolution, and comparative genomics to study the structure and evolution of the genome, natural populations, to resolve the evolutionary forces acting on individual genes, and to functionally annotate the genome (particularly that of Drosophila). Our work includes experimental studies of sequence variation and gene structure and function, as well as the development and refinement of statistical and computational methods for detecting selection on synonymous sites, distinguishing natural selection from population demography, and for detecting molecular coevolution. Current work focuses on the molecular genetic basis of adaptation in insects, mammals and plants, the functional significance of synonymous (“silent”) variation, the genomic distribution of recombination and its influence on levels and the genomic and geographic distribution of DNA sequence variation, and on the use of evolutionary diversification to understand molecular and evolutionary processes that modulate fertilization and regulate germ line stem cell maintenance and differentiation in Drosophila.
Main themes of research include:
- Genome scans for footprints of adaptation
- Distinguishing footprints of natural selection from non-equilibrium demography
- Synonymous mutations: just how “silent” are they?
- Evolution of reproductive genes in Drosophila and mammals
- Evolution of genes that regulate germ line stem cells in Drosophila
- Simple sequence evolution (microsatellites)
Some new areas include:
- Genomic distribution of recombination (any evidence of hotspots in Drosophila?)
- Structural correlates of adaptive evolution