EVOLUTIONARY RESPONSES TO DROUGHT
The frequency and duration of drought is increasing worldwide. We are investigating phenotypic and genetic responses to water limitation for plant species found across moisture gradients. Of particular interest is how water limitation affects floral traits such as nectar reward and floral display, and how this changes interactions between plants and pollinators.
Human-dominated systems can negatively affect local biodiversity by acting as a barrier to dispersal. We investigate how dispersal of native pollinators and the plants they pollinate differs between forested and agricultural areas by focusing on dispersal dynamics of Euglossine bees in Southern Costa Rica. Euglossines are key pollinators of many plants, including over 700 species of orchids, and some economically important plants such as the Brazil nut tree. To date we have found that species differ in their level of dispersal across fragmented landscapes, and we are currently determining why these differences occur and how this affects gene flow in plant populations.
AGROECOLOGY OF POLLINATION SYSTEMS
About one-third of agricultural crops require bees for pollination, and most crops are pollinated by commercially-managed bees. We are characterizing the effects of commercially-managed bumble bees on the ecology and genetic integrity of native species, and investigating how to increase the abundance of native pollinators in agricultural systems.