Most of my work involves the evolutionary ecology of plant-animal interactions, with particular emphasis on plants and pollinators. As I am interested in the overall interaction rather than any particular component, my work ranges broadly, from studies of pollinator behaviour and cognition to the biology of pollen-pistil interactions. Presently, my main interest is the role of animal pollination in the diversification of the large herbaceous genus Penstemon. With collaborators in the U.S. and Norway, I seek to understand the selective forces behind evolutionary shifts from insect pollination to bird pollination-shifts that have occurred independently in several lineages within Penstemon . I seek to quantify the value of different pollinators through detailed studies of the efficiency with which they transmit pollen grains. I have also brought this perspective to applied questions of agricultural pollination. On the conservation side, I am intrigued by claims of widespread pollinator declines, but frustrated by the dearth of relevant evidence. In 2001, I anticipate starting a "100-year study" of insect pollinator populations in Ontario.