My research focuses on the systematics, evolution and ecology of aquatic flowering plants

Looking for Najas in a Louisiana cypress swamp
 An Everglades 'gator watches as we search for aquatic plants
Eriocaulon plants with some visiting insects

Aquatic plants

  Male spathe of Vallisneria natans (photo by Lei Chen)
  Seeds (left to right) of Najas flexilis, N. muenscheri, N. guadalupensis
A rare chasmogamous flower of Glossostigma cleistanthum

Nymphaea 'William Phillips', the world's first intersubgeneric
hybrid waterlily
Leaf x-section of Glossostigma cleistanthum
     Aquatic plants are of interest to systematic biologists because many of the groups are quite ancient, exhibit extreme plasticity and reduction in form, and generally have been poorly studied.  We reconstruct the evolutionary history (phylogeny) of aquatic plants using a combination of morphological and molecular (DNA sequence) data, which facilitates their evolutionary study.  Results of our research are used to improve the taxonomy of various aquatic plant groups.  Some of our past and present projects have included:

  • Phylogenetic studies (e.g., subclass: Alismatidae; orders: Alismatales; Ceratophyllales, Nelumbonales, Nymphaeales; families: Elatinaceae; Haloragaceae; Hydrocharitaceae; Lemnaceae; Menyanthaceae; Podostemaceae; Sparganiaceae; Zosteraceae)
  • Aquatic plant hybrids (Aponogeton; Elodea, Myriophyllum; Najas; Nuphar; Nymphaea; Nymphoides; Potamogeton; Vallisneria)
  • Evolutionary studies of water pollination (hydrophily) and marine colonization (seagrasses)

    2009 workshop on seagrass dispersal (Perth, Australia)

I also am the director of the CONN herbarium, which houses the department's collection of plant specimens used for research, teaching and outreach.  These collections include fossil plants, nonvascular plants, algae, and fungi as well as flowering plants (angiosperms).