Examining microbial biodiversity in soil: A research‐based introductory biology laboratory course

Abstract

We report a novel introductory biology laboratory course designed as an independent, on‐going research program, with students as the primary researchers. This course aims to develop an understanding for biology through inquiry‐based laboratory experiments, and specific learning objectives are listed in Table 1. Students work in teams to collect, analyze, and present original data while learning core concepts and laboratory methods. Specifically, we examine if and how soil microbiomes are different for native vs. invasive plant species in the Southern California diversity hotspot. Students analyze soil properties such as moisture and pH and correlate them to functional and genetic biodiversity of microbiomes, assessed by carbon source utilization and 16S rDNA sequencing. Together, these elements span macroscopic to molecular scales, providing opportunities to connect student learning across biology disciplines.This presentation will focus on the design, implementation, and evaluation of the course. Laboratory experiments are designed to be completed by introductory students within a 3‐hour laboratory and 1.5‐hour lecture per week while allowing for the reliable collection of research data. We found that student‐generated data are consistent across groups: soil genomic DNA preparations and PCR clean‐up reactions have standard deviations <10% of average DNA concentrations, and >95% of PCRs result in products at appropriate sizes. Student outcomes are evaluated by pre‐ and post‐surveys and ‐tests to track changes affective domain (Science Motivation Questionnaire II), self‐efficacy in research skills (Classroom Undergraduate Research Experience survey), and ability to draw conclusions based on data (open‐ended questions that test scientific argumentation). Learning objectives Activities Student assessments Understand functional and genetic biodiversity Discuss material in laboratory and lectures Quizzes in lectures, laboratory reports Develop testable hypotheses and design controlled experiments Carry out scientific processes in the context of the course Data collection by students, laboratory reports Draw conclusions based on data and evidence Analyze and discuss laboratory data using statistics Figures and results in laboratory reports Communicite scientific results in a publication‐style laboratory report Write, review, and revise laboratory reports Laboratory reports, peer review of laboratory reports