Our lab works on various aspects of insect-microbe interactions, and our projects can be classified into two categories. Our basic research is concerned with the roles microbes play in the trophic specialization of insects. Our applied work is focused on the isolation and optimization of entomopathogens for the control of urban pests, especially wood-destroying pests. We are also interested in developing biocontrol technologies that disrupt nutritional symbioses in insects.
Trophic specialization and the microbiome
Trophic specialization is a major force of diversification, and insects have colonized many niches that are either absent or very uncommon among vertebrates. Many of these specialized insect clades rely on their microbiomes for locating and digesting their food. However, how these feeding strategies evolved remains shrouded in mystery....
We work on the ecology and evolution of host-microbe interactions primarily in the context of insects feeding on dead plant and animal material.
We are also interested in developing safe and environmentally friendly approaches to control urban pests. These projects primarily involve the development of entomopathogens for biological control or the disruption of symbioses.
Digesting forests in 1 μL ecosystems
Animals subsisting on fibrous plant material, living or dead, are especially dependent on their gut microbiomes. They have a range of digestive adaptations, including modified chewing parts, and specialized intestinal tracts. This variety of physicochemical conditions produced in their guts is reflected in the structuring of the tiny intestinal habitat into many microhabitats, each colonized by unique microbiomes.
Similar to herbivory in mammals, saproxylophagy or the digestion of wood comes with exceptional challenges that require unique morphological, physiological, and behavioral adaptations. Yet, in contrast to the stark absence of saproxylophagy in vertebrates, many insects, including beetles, cockroaches, and termites, have evolved the ability to feed on wood.
We are interested in understanding how the digestive adaptations in wood-feeding insects interact with the microbial ecology of the gut to symbiotically digest wood. Our main model organisms for asking these questions include termites, cockroaches and passalid beetles.
We have also developed gnotobiotic cockroach systems that allow us to define the environment or microbiome composition. for experiments requiring more control.
Patterns of parallel evolution in microbiomes
Patterns of parallel evolution between hosts and their symbionts are an excellent starting point to ask questions about the fidelity and history of symbiotic interactions. Many such patterns have been discovered in intracellular (endo)symbionts of insects where host and symbiont phylogenies track each other. However, more recently, a similar congruency termed "phylosymbiosis" has been observed between many hosts and their associated microbiomes.
The recapitulation of host evolutionary history in microbiome composition/structure prompts many cool questions about the mechanisms that control vertical inheritance of microbiomes and maintain specific environmental conditions in the gut.
Our lab focuses on insects feeding on dead plant and animal material. We use phylogenetics, metagenomics, and behavioral assays to explore patterns of parallel evolution and the forces that generate them.
Eaters of the dead
(and those of the living)
By specializing on decaying organic matter of animal origin, flies, including flesh flies, house flies, and blowflies, have evolved in microbe-rich habitats. These insects play a central role in the turnover of dead animal material, but a few have also evolved to be parasites – the obligate feeding in or on another living organism. Blowflies therefore offer an excellent case study in the evolution of both necrosaprophagy as well as parasitism.
Aside from questions on phylosymbiosis, our lab is interested in the roles microbiomes play in the location and digestion of food in blowflies and in the evolution of parasitism. Because filth flies are implicated in the transmission of many bacterial pathogens, we are also interested in their serious roles in the spread of human and veterinary disease.
Many of our questions rely on our gnotobiotic models based on blowflies that allow us to conduct controlled experiments with flies of known microbiome composition.
The search to find safe, environmentally responsible, and economical alternatives to chemical pesticides has intensified in recent years. However, in comparison to the agricultural sector, the use of biological control against urban pests is very limited. As the public demand for biological alternatives to chemical pesticides mounts, there is an opportunity to explore the use of entomopathogens and other ecofriendly methods against urban pests.
Our projects relating to biological control involve the isolation and strain improvement in entomopathogens. We are also interested in optimizing entomopathogen efficacy by synergizing with traditional methods and methods that involve the disruption of symbioses in target pests.
Our work primarily revolves around the control of termites, but collaborate closely with other labs in the Urban Entomology Program on projects to control cockroaches and bedbugs. Some of our research also involves agricultural pests. This work is entirely supported by our industrial partners in the Research Triangle.