I am a Ph.D. Candidate at Colorado State University, where I am co-advised by Dr. Ruth Hufbauer and Dr. Andrew Norton. In my research I use an introduced plant, common mullein, as a means to evaluate how changes in herbivore and pollinator communities shape a plant's evolutionary trajectory and ecology.
Using a plant invasion to study plant-herbivore interactions :
In a plant’s native habitat, they have to defend against many different types of insects, but mostly specialists. When plants are brought to a new habitat, they often lose the specialists that have fed upon them for thousands of years, but are still attacked by generalists. As a result, plant invasions are a fascinating natural experiment. They allow us to compare two sets of plants that have experienced two very different types of insect attack (one mostly by generalists, and one mostly by specialists).
To this end, I use common mullein, a widespread invader within North America, to ask how plant populations evolve in response to a shift from specialist- to generalist-dominated insect communities. Much of my work on this topic has been done in close collaboration with Dr. Christina Alba at
the University of Florida.
In a plant’s native habitat, they have to defend against many different types of insects, but mostly specialists. When plants are brought to a new habitat, they often lose the specialists that have fed upon them for thousands of years, but are still attacked by generalists. As a result, plant invasions are a fascinating natural experiment. They allow us to compare two sets of plants that have experienced two very different types of insect attack (one mostly by generalists, and one mostly by specialists).
To this end, I use common mullein, a widespread invader within North America, to ask how plant populations evolve in response to a shift from specialist- to generalist-dominated insect communities. Much of my work on this topic has been done in close collaboration with Dr. Christina Alba at
the University of Florida.
Below-ground plant-herbivore interactions: One of the reasons common mullein is so interesting to work with is that plants in North American (introduced range) seem to have completely escaped the insects that feed on their roots. Conversely, plants in Europe (native range) have root damage more often than not. This striking difference emphasizes that where a plant stores defense (old leaves, young leaves, roots) can be just as important as how much of a defense it produces. It makes sense that plants would allocate their limited resources to best defend the tissue that faces the highest risk of being eaten. We can use common mullein to test this hypothesis. If this hypothesis holds true, we would expect plants in North America to defend their roots less, given their low risk of damage, and instead invest more in defending their still vulnerable leaves as compared to plants in Europe.
Plant-pollinator interactions:
Evolution of floral plasticity: Insects play a fascinating role in plant evolution: they can either act as beneficial pollinators, or as detrimental plant eaters. Both types of insects interact with the same plants at the same time. One more reason common mullein is so interesting to work with is that their flowers are visited not only by a variety of short- and long-tongued bees, but also by a seed-feeding weevil, which lays its eggs in the plant's open flowers. This means a flower has to be attractive enough to attract pollinators, but not attractive enough to risk attracting the damaging weevils. Both pollinators and weevils are within common mullein’s native and introduced range. As a result, we can investigate yet a third factor: how leaf herbivory mediates this delicate balance in floral traits. Does floral attractiveness vary when leaves have historically experienced high-risk (native range) versus low-risk (introduced range) of being eaten?
Evolution of floral plasticity: Insects play a fascinating role in plant evolution: they can either act as beneficial pollinators, or as detrimental plant eaters. Both types of insects interact with the same plants at the same time. One more reason common mullein is so interesting to work with is that their flowers are visited not only by a variety of short- and long-tongued bees, but also by a seed-feeding weevil, which lays its eggs in the plant's open flowers. This means a flower has to be attractive enough to attract pollinators, but not attractive enough to risk attracting the damaging weevils. Both pollinators and weevils are within common mullein’s native and introduced range. As a result, we can investigate yet a third factor: how leaf herbivory mediates this delicate balance in floral traits. Does floral attractiveness vary when leaves have historically experienced high-risk (native range) versus low-risk (introduced range) of being eaten?
Community Ecology: Introduced plants may compete with native plants for pollinators, but they may also support native plants by providing an oasis of nectar and pollen that supports healthy pollinator communities. Understanding which role common mullein plays within the foothills of Colorado is important for refining existing management strategies for native and introduced plants alike. Right now I am working with Larimer County Open Spaces to look at how common mullein alters pollinator visitation and pollinator efficacy to the native species within the surrounding landscape.
Native Bee Abundance and Diversity: The decline of pollinators (in particular bees) is especially concerning to the farmers who rely on these insects to produce healthy, high-yield crops. However, far too little is known about native bees within the grasslands that often surround these agricultural landscapes, or how different management strategies may impact these bee communities. As a result, I am currently collaborating with researchers from Colorado State University, University of Colorado (Boulder), and University of Wisconsin (Madison) on a USDA-funded project looking at native bee abundance and diversity within the agricultural landscapes of eastern Colorado. After 2 years of sampling, we have finally completed our surveys and are working on processing and identifying our specimen. Check out Adrian's blog to follow our progress and to learn about our most recent findings.
Native Bee Abundance and Diversity: The decline of pollinators (in particular bees) is especially concerning to the farmers who rely on these insects to produce healthy, high-yield crops. However, far too little is known about native bees within the grasslands that often surround these agricultural landscapes, or how different management strategies may impact these bee communities. As a result, I am currently collaborating with researchers from Colorado State University, University of Colorado (Boulder), and University of Wisconsin (Madison) on a USDA-funded project looking at native bee abundance and diversity within the agricultural landscapes of eastern Colorado. After 2 years of sampling, we have finally completed our surveys and are working on processing and identifying our specimen. Check out Adrian's blog to follow our progress and to learn about our most recent findings.
