95th ESA Annual Meeting (August 1 -- 6, 2010)

COS 15-7 - Community assembly of bombus: Relatedness, tongue length and competition

Monday, August 2, 2010: 3:40 PM
407, David L Lawrence Convention Center
Alexandra N. Harmon-Threatt, Biology, Washington University in St.Louis, Saint Louis, MO and David Ackerly, Integrative Biology, University of California, Berkeley, CA
Background/Question/Methods:

Bumblebees (Bombus) have been shown to partition plant resources by co-occurring species having different tongue lengths. However, how tongue length is conserved through the phylogeny of bumblebees as well as how species that co-occur are related to one another is largely unknown. Using a comprehensive phylogeny created by Cameron et al (2007) I tested whether tongue length was phylogenetically conserved and compared community composition at multiple scales in North America.  Using published data on tongue length and community composition I was able to determine community relatedness and whether tongue length is truly evenly dispersed as suggested by previous studies.   

Results/Conclusions:

Tongue length showed significant conservation compared to randomly created trees. We found that communities are more commonly evenly dispersed than underdispersed which helps support that tongue length is conserved and that communities are assembled based on this trait. Only communities in extreme environments showed significant clustering of species. The co-occurring communities showed the same trend. Future work will look at the trait values to determine how they are dispersed in communities.