My principal areas of interest, within systematic biology, are in the theory and practice of phylogenetics and species delimitation. In the first of these areas I am engaged in studies of phylogenetic relationships within the grass family (Poaceae) and across monocots as a whole, using molecular and morphological character sets. My studies at the species level have involved the development of general approaches and specific methods for inferring species boundaries on the basis of population variation patterns. I have employed these methods in my studies of species boundaries in the grass genus Puccinellia, and these analyses have contributed to my floristic studies of this genus.

I teach two courses for undergraduates, one of them focusing on the systematics and diversity of vascular plants (BioPL 248), the other on the diversity and evolutionary biology of the grass family (BioPL 359). In both courses I emphasize the importance of different sources of evidence (structural characteristics, DNA sequence variation, etc.) and analytical procedures in interpreting relationships within these groups of plants. These courses also include lectures on the interface between systematics and related fields, such as pollination biology, other aspects of reproductive biology, evolution, ecology, and the history of biology. Each course includes a weekly laboratory in which the diversity of the target group is surveyed, and in which students develop and practice the skills of interpretation of plant structures and identification of plants.