A central goal of the lab is to better understand the community ecology of ants and termites. To accomplish this, we use experimental and comparative approaches to quantify a suite of variables including body size (biomass), colony size, species richness, abundance, and behavioral dominance to paint a detailed picture of local and regional ant faunae. This research recognizes the unique characteristics of eusocial insects that impact their ecology.
Insect mediated ecosystem services
We are interested in understanding and valuing a wide variety of insect mediated ecosystem services. To accomplish this we have initiated large-scale, long-term manipulative field experiments in central Florida to understand the how dung beetles, fire ants, and pasture management all interact to affect the delivery of disease control and grass production services in grassland ecosystems used for cattle production. Collaborators include Mahadev Bhat and MAERC.
Impact of ant nests on soils
Soil organic carbon is an important property of ecosystems that impacts soil fertility and the global carbon cycle. Animals have been shown to affect carbon in soils, but it is poorly understood how different types of animals ultimately affect processes that determine the amount of carbon in soils. Ants are highly abundant animals that nest in soils all over the world. Their nests impact bacteria and fungi living in the soil which, in turn, affect soil conditions including carbon content. Ants may therefore be an important animal group affecting the processes that determine carbon content in soils. We are interested in understanding how highly abundant insect animals that live in the soil alter and improve conditions for bacteria and fungi that live in or near ant nests. Over many ant nests across large areas, these impacts on soil conditions and microbes may be very large and important for determining, for example, how much carbon is present in soils. We employ large-scale surveys and whole nest manipulations (experiments) to understand and scale ant nest impacts on soil communities to whole ecosystems. Collaborators include Mark Bradford, Jon Seal, and Katrin Kellner.
Invasion events offer unique opportunities to quantify the importance of contemporary species interactions and habitat features in determining invasion success and, more broadly, in shaping community structure. This is because, typically, invasive species have no historical geographical overlap with native fauna or the environment they invade, and thus, no shared evolutionary history.
In collaboration with Walter Tschinkel, we have been conducting large-scale, long-term manipulative field experiments, field surveys, and molecular studies in Florida to understand the relationships among human-caused disturbance, invasion, dispersal, and competition.
Related, ongoing applied conservation work is focused on mitigating invasive fire ant impacts on threatened and endangered ground-nesting vertebrate wildlife (sea turtles, Florida grasshopper sparrows) in collaboration with Florida Fish and Wildlife Service.
Termite ecology and dead wood ecology
Decomposer communities are understudied, yet vital to the function of whole ecosystems. The decomposition of woody material is especially important in many temperate and tropical ecosystems, yet is virtually unstudied, even in well-studied ecosystems such as eastern US temperate hardwood forests. Wood rot fungi and subterranean termites in the genus Reticulitermes are believed to be the primary groups that control decomposition rates of woody material in eastern US forests, but beyond very broad patterns (e.g. decomposition proceeds more quickly in warmer climates) there is little known about how abiotic factors (temperature, soil moisture), phylogeny (evolutionary relationships and traits of wood rot fungi), and biotic factors (fungal species composition, channelization by invertebrates, species interactions) interact to govern rates of decomposition and mineralization of woody materials. We are pursuing a deeper understanding of termite and decomposer community ecology in the eastern US. Collaborators include Mark Bradford and Robert Warren.
Communities are comprised of many species, each with their own unique characteristics and distribution. Because of this, communities are enormously complex systems and can be difficult to study in any detail. To better understand community-scale patterns and biological invasions, it is necessary to pursue a deeper understanding of the biology of at least some of the species within the community. This is particularly true of the ants which, as a group, are generally lacking adequate quantitative natural history data on the “characters” of eusociality, such as colony size and worker body size, that is relevant to their ecology and evolution. To remedy this situation, we have ongoing population-level projects aimed at better understanding the biology of both native and exotic species ranging from New England to Florida. This research includes a variety of basic natural history studies designed to quantify the unique characters of eusocial insects (colony size, worker demography, reproductive strategies) that allow a deeper understanding of their ecology and evolution.
Practical aspects of sampling limitations affect our ability to understand and preserve biodiversity. A goal of the lab is to identify and quantify practical and statistical problems with traditional methods of sampling ants (pitfalls, baits, litter sampling) and to improve upon them. A second goal is to create novel methods that allow experimental manipulations of populations and communities (colony removals, colony transplants) and environmentally sound management strategies for pest ants. This ongoing line of research is an integral part of all of the basic research we conduct.