Eco-Evolutionary Assembly of Hyperdiverse Communities

High-diversity ecosystems have inspired a rich body of theory to explain community assembly and the maintenance of biodiversity. In these communities, extreme numbers of species often occur together at local scales, yet species composition often varies substantially among communities with similar environmental conditions. Moreover, large numbers of rare species may encounter one another infrequently, suggesting a limited role for pairwise species interactions such as interspecific competition. These observations challenge classical explanations of diversity maintenance based solely on niche selection at local scales. Using an experimental approach, we are investigating the relative importance of dispersal, ecological drift, and niche selection at local and regional scales as drivers of community assembly in the hyperdiverse longleaf pine (Pinus palustris) ecosystem of the southeastern United States. At local scales, this ecosystem boasts the highest plant species richness in North America (40-50 species/m2) and is among the most threatened ecosystems in the world (>98% habitat loss), providing abundant opportunities to contribute towards biodiversity conservation.

 

Acknowledgements & Collaborators:

Our principal collaborators include Kyle Harms (Louisiana State University) and Paul Gagnon (Murray State University). We thank the Eglin Air Force Base Jackson Guard (Florida), the Girl Scouts of America and Camp Whispering Pines Girl Scout Camp (Louisiana), and the National Science Foundation (DEB 1144084) for supporting our research.

Quadrat (1 x 1 m) containing ~40 plant species in an upland longleaf pine community,
Camp Whispering Pines, Louisiana
Sundew (Drosera sp. [Droseraceae])
in a wet longleaf pine savanna,
Apalachicola National Forest, Florida

Longleaf “Diversity, Dominance & Disturbance” Team, Eglin Air Force Base, Florida
(August 2013)