Do You Live Under a Rock? Using Benthic Macroinvertebrates to Teach Classification

Because of ineffective teaching methods and instructor reliance on lecturing, biology students often struggle with interpreting cladograms and dichotomous keys. This, in turn, leads to misconceptions and inefficient recall of content in evolutionary units of traditional biology courses. Biology is a science that studies life and systems, and it makes sense that educators should utilize systems-based approaches to teaching. Therefore, I utilized benthic macroinvertebrates (bottom-dwelling species lacking a backbone) as model organisms to teach modern classification concepts. Further, this category of species can be used as a paradigm for studying virtually all aspects of biology. For this activity, students followed modern sampling techniques to find and identify organisms using dichotomous keys based on physical traits. From there, they generated cladograms to hypothesize evolutionary relationships between species. Following the conclusion of this activity, students took a summative assessment that asked them to interpret cladograms related to benthic macroinvertebrates, as well as other categories of species. This suggests that students were able to connect their newly learned content to other aspects of biology. Because students can identify species with relative ease, benthic macroinvertebrates act as excellent model organisms for teaching evolutionary concepts such as dichotomous keys and cladograms. Additionally, exposing students to biotic factors near them could be effective for promoting life science and evolutionary content. This activity offers a novel way to introduce challenging concepts by utilizing local species.