Heather Grab

Graduate Student

   My research focuses on the ecology of agricultural ecosystems with the aim creating more resilient farming practices by understanding and managing the services provided by arthropods. I am currently exploring different areas related to this theme from the molecular to the landscape level.
   In the Danforth lab, I have investigated how land management decisions, ranging from land use patterns surrounding farms to restoration of habitats bordering agricultural fields, influence pollination services and biological pest control in strawberry. In this system, molecular diagnostic techniques developed in the Danforth lab have allowed insights into the species identity of the parasitoids of the most economically significant pest; revealing that exotic species have excluded the native enemies of this pest.
   I am also interested in how land use changes alter the phylogenetic structure of communities. Prior work by Mia Park in the Danforth lab has shown that pollinator communities in eastern apple orchards have lower species richness at sites that have few natural habitat patches in the surrounding landscape.  But this loss of taxonomic diversity may not be uniform across the bee phylogeny. In other words, some closely related bee groups may be more at risk that others because of their shared evolutionary history and functional traits. By reconstructing a phylogeny of the apple pollinator community, we can test this question and also determine whether loss of community phylogenetic diversity leads to a reduction in the delivery of pollination services to apple. 
 
I have been keeping the Danforth lab thermal cyclers busy with a number of my side projects.

  • Pathogen screening of flowers and bees from well-characterized plant-pollinator networks (collaboration with Laura Figueroa & Scott McArt)
  • Exploring patterns of Ascosphaera in Osmia populations (with Erin Krichilsky)
  • Using next-gen sequencing techniques to identify pollens from bee provisions (collaboration with Alex Keller, U Würzburg)

  
Learn more about my research interests at my website.