Signal Evolution in Lampyrids (fireflies or lightning bugs)
Using fireflies (Lampyridae, Coleoptera) as a model system, we are using phylogeny-based approaches to study the evolution of signal phenotypes and the production and reception of light signals under different environmental conditions (habitat characteristics, other signaling species and predators). We are also working on sensor evolution, aposematic signaling, and the biogeography of different firefly genera. The firefly system is exceptionally well suited as a study system, because it allows us to connect signal phenotypes with the underlying genes and their molecular evolution. Our lab has extensive field experience in firefly behavior, light emission measurements, sensor morphology, molecular methods and phylogenetics.
1. Worldwide phylogeny of fireflies and evolution of signal mode. In collaboration with Seth Bybee (Brigham Young University) and Marc Branham (University of Florida) we are generating a world-wide genus-level firefly phylogeny of Lampyridae to study signal evolution (light signals, pheromones) and associated sensor morphology in this beetle family. Ultimately this worldwide phylogeny can be utilized by firefly researchers worldwide as a reference for phylogeny-based studies with more limited taxon sampling.
2. Species-level phylogenies of fireflies and signal evolution. In collaboration with Dave Hall (University of Georgia) we utilized firefly genomes and transcriptomes to generate a probeset (500 probes) for Anchored Hybrid Enrichment as a basis for the worldwide phylogeny. We are also using them to generate robust species-level phylogenies to test hypotheses on selection and address communication-related questions in the visual communication system of fireflies. These phylogenies serve as a tool to investigate signal evolution (pheromones, flashes, glows) in this group, including the influences of natural and sexual selection on the evolution of the diverse flash patterns among North American fireflies. In addition, we are doing fieldwork to investigate how individual firefly communities divide up the signaling space between species to reduce mistakes in species identification and mate choice, and how they protect themselves from predators.
3.Signal production and reception. We are sequencing genes involved in light production (luciferase) and reception (opsins) to examine whether selection acts on signal production and reception in fireflies. In addition, we are doing fieldwork (ambient light measurements in different habitats and measurements of firefly light spectra) to investigate the light color evolution in fireflies.
4. Biogeography of fireflies. In collaboration with Jim Lloyd (University of Florida) we are investigating the biogeography of North American fireflies. The species-distributions of the ~150 North American firefly species differ widely in location and area. Our research will identify physical (elevation, precipitation and temperature, vegetation cover, etc.) and biological (congeners, other firefly genera, firefly predators, etc.) variables that best explain the biogeography of NA firelies. This work will be expanded by Luiz Silveira to select taxa in Central and South America.
Science Education & Communicating Science
My main interest in science education is guided by an effort to facilitate critical thinking in introductory biology students and the type of active learning required to foster it. Similary, being able to communicate scientific research findings to broader audiences is an essential skill set for graduate students, as well as undergraduate research students.
1. Teaching scientific thinking skills to undergraduate students: Many students enter the University with excellent memorization skills, but struggle to make the transition to scientific (critical, evidence-based) thinking. In contrast to memorization, based on more or less passive consumption of the class material, critical thinking requires active processing of information, and higher-level cognitive skills (application, analysis, synthesis, and evaluation). These skills help students succeed in the sciences and in college, but are also considered life-long learning skills that inform educated decisions, and are crucial for a successful career in any field.
2. Faculty workshops in Scientific Teaching: As the Director of the National Academies Southeast Summer Institute on undergraduate biology education (2011-2016; funded by HHMI) I organized weeklong summer workshops (2012-2015), with follow up-meetings in spring (2013-2016). These institutes served 139 faculty and administrators from >25 Institutions across the Southeast, and helped faculty develop assessment design, active learning and inclusive teaching skills to facilitate critical thinking for all students. The final meeting (supported by HHMI and ORAU) was held in July 2016.
3. Communicating science between disciplines and to broad audiences: It is essential that science graduate students can communicate their science to colleagues within their discipline, but also across disciplines, and to interested non-expert audiences. For this purpose I have developed a Communicating Science course for graduate students. I am also interested in how different views of the scientific process in different biological subdisciplines affect their approach to science (e.g. accommodation of hypotheses versus testing of hypotheses) and the interpretation of data. By developing a common communication framework, I am aiming to facilitate science communication between students in the different biological research disciplines.