Mutualism disruption as a mechanism of biodiversity loss
Mutualisms are thought to be vital for maintaining biodiversity in an ecosystem. The relationship between native plants and arbuscular mycorrhizal fungi (AMF) is especially important, but also vulnerable. AMF cannot survive for long without a plant partner, and native plants can suffer physiological declines with a loss of their fungal symbiont. Many invasive plants release antimicrobial chemicals into the soil, killing AMF hyphae. My research focuses on the reproductive and mating system consequences of mutualism disruption for native plants, which can lead to a mechanistic understanding of the loss of biodiversity seen when an exotic invader enters a community.
Pollen/gynoecium interactions as mediators of reproductive isolation
Closely related plant species often have incomplete reproductive isolation. Although they may be capable of producing offspring, these offspring are likely weak or unfit. It is a waste of resources for a plant to produce an offspring that cannot reproduce or is more likely to die. Therefore, there should be strong selection for closely related sympatric species to avoid hybridization. In the genus Collinsia (Plantaginaceae), there are repeated sister pairs where one taxon is highly outcrossing and the other is highly selfing. We are investigating several traits of pollen/gynoecium interactions to try to understand where isolation occurs in these sympatric sister species.