Katherine R. Goodrich, Associate Professor
Cynthia H. Sarnoski Science Faculty Fellow
Widener University

Topic:  Flowers, flies, and fermentation:  floral mimicry and pollination ecology of pawpaw

Abstract:
Pollination ecology involving floral mimicry has fascinated researchers for more than a century, especially when it involves floral mimicry of a non-floral species or substrate.  Classic examples of flowers mimicking a dead animal or a receptive female insect are relatively well-known; however fewer studies document floral mimicry of fermenting fruits or other ecologically-relevant models which attract a diversity of beetles, flies or other taxa not normally associated with pollination.  We are interested in the pollination ecology and potential for floral mimicry in Asimina triloba (Annonaceae), a woody species with spring-blooming, maroon, yeasty-smelling flowers that are pollinated by fermentation-loving species of Diptera.  While the unusual floral phenotype and associated insect taxa suggest mimicry of a non-floral fermenting substrate, a more rigorous set of criteria must be met to establish floral mimicry.  We must demonstrate (1) the occurrence of an ecologically-relevant model upon which the mimic is based, (2) that the visitor identity and behavior at the model overlaps with the pollinator identity and behavior at the flowers, and (3) that the floral traits overlapping with the model are novel and adaptive.  Here I present data documenting the overlap of floral phenotype with several potential ecologically-relevant models.  I also characterize the insect taxa associated with the flowers and with the potential models.  We are in the process of placing the floral phenotype and pollination strategy of Asimina triloba within a broader phylogenetic context, mapping floral character evolution within the genus Asimina, with particular focus on floral traits overlapping with non-floral model substrates.  Finally, we will document the pollination ecology of several additional species of Asimina, comparing species with similar yeasty maroon flowers (Asimina parviflora, A. pygmaea, and/or A. tetramera) to species with larger white flowers and varied floral scents (A. incana, A. obovata, A. longifolia, and/or A. reticulata). 

Host Lab: Kramer