PS 22-86 - Lichen-associated micro-organisms as subjects of course-based undergraduate research in community ecology

Tuesday, August 8, 2017
Exhibit Hall, Oregon Convention Center
Jessica R. Coyle, Po-Ju Ke and Tadashi Fukami, Department of Biology, Stanford University, Stanford, CA

Lichens are understudied components of many ecosystems, both within the general ecological literature as well as in university courses. Yet, several features make lichens advantageous subjects for course-based undergraduate research in ecology. For one, lichens are comprised of multiple interacting species in discrete micro-communities that can easily be sampled in any season. They are biologically active whenever light and water are adequate, making them feasible subjects for year-round courses. Furthermore, several species are abundant, widely distributed and easily recognized with little training. Our goal was to conduct a pilot course to explore the potential for using two lichen species as a focus of a research-based undergraduate community ecology lab class. We designed learning objectives that addressed the personal, social, and intellectual skills necessary for scientific research as well as specific skills in data analysis, science communication, and ecology. Our primary aims were to determine (1) which aspects of the lichen-based ecological system were most engaging and feasible for student research projects and (2) which activities helped student achieve the learning objectives. We administered pre- and post-class assessments evaluating student progress in each objective as well as conducted mid- and end-of-class surveys of self-perceived development and the benefits of each assignment.


We modeled the class after a previously successful course in which teams of students propose and evaluate hypotheses using data collected by the entire class and then present their results orally and in a final scientific paper. We followed the same format, with the class collecting data on four communities of microorganisms associated with the two focal lichen species: green algae, internal and external bacteria, and endolichenic fungi. Lichens were collected from Jasper Ridge Biological Preserve (California, USA) where the students also measured abiotic variables that could impact lichens. Bacterial and fungal communities were studied using culture-dependent methods and DNA barcoding was used with algal and fungal communities. Students proposed hypotheses that spanned a broad variety of concepts, from dispersal limitation to pathogen impacts on community metabolism. Projects gravitated toward organisms for which students had the most hands-on experience earlier in the course. Mid-quarter surveys indicated that the most beneficial activities were those designed to teach specific concrete skills (e.g. data analysis in R and writing structure) and that students did not learn from journal assignments designed to develop personal and social research skills. We will report results from the post-class survey and assessment after the course concludes in March.