Phylogenetic biology and systematics, especially of the Agaricales (mushrooms).
genetics of speciation, including patterns of morphological vs genetic divergence, and analysis of the genetic factors underlying development of intersterility between related species.
population biology of fungi, estimation of breeding systems and measurement of gene flow in natural populations. Fungi currently under investigation include the oyster mushroom (Pleurotus ostreatus) as well as several species of medically important fungi (Candida albicans and Cryptococcus neoformans)