Forty meters below the lush green of tropical canopy is the brown world where bacteria and fungi rot the dead. In doing so these microbes feed a diversity of organisms and recycle the forest's nutrients. The brown world is intriguingly patchy--the abundance of BFW critters in adjacent bits of litter can vary 100-fold, some litter patches buzzing with life while others are strangely sterile. We propose that this patchiness arises from the interaction of predators, defenses, and the chemistry with which they build new hyphae, exoskeletons, and toxins. MORE

The ants are common and dominant parts of most terrestrial ecosystems. We travelled across the New World, from tundra to tropical rainforest, sampling soil ant communities along the way to answer the question, how and why do these communities vary in size, abundance, and diversity? We found that two key ecosystem variables, temperature and productivity repeatedly helped us understand why some habitats had a 100 times more ants, more species, as well as some suprising variability in the average size of an ant colony as you move from place to place across the planet. MORE

Of the 25 or so elements required for life Na is unique. Na is relatively unimportant to terrestrial plants. Plant consumers—herbivores and decomposers--in contrast, must concentration Na 100-1000 fold over the 1.0 mg kg-1 found in their food. This biochemical disconnect between plants and their consumers suggests that where Na is in short supply, this shortage will ramify through the ecosystem, starting with herbivores and decomposers. We have been exploring how different causes of Na shortage--distance from oceanic inputs (at broad scales) and roadsalt (at 1 km scales)--shape the dietary preferences and activity of ants, termites, and other members of the brown food web. One hot project funded by an NSF EAGER grant, is the fertilization of large plots in Ecuador with rainfall whose NaCl concentration mirrors salty Panama. MORE SOON

Did we mention that 25 or so elements are required for life? ;-) In an NSF funded collaboration with Adam Kay at U. St. Thomas, we are using the 400 or so ant species from Barro Colorado Island to explore how three--carbon, nitrogen, and phosphorus--can help us understand the development and evolution of ant niches. Specifically, we are testing the degree to which five functional traits--colony size, worker size, tempo, foundress starvation resistance, and growth rate--are variously constrained by access to C, N, and P. We then scale up these results to explore how ant community behavior and composition vary along natural and artificial gradients of these elements. MORE SOON

"I predict there will be erected a two- or three-way classification of organisms and their geometrical and temporal environments, this classification consuming most of the creative energy of ecologists. The future principles of the ecology of coexistence will then be of the form “for organisms of type A, in environments of structure B, such and such relationships will hold”. 
Robert MacArthur 1972