Simplifying the Complexity of Biological Systems Learning
As foundational tools in biological science, models and modeling warrant representation in college biology curricula. Documents such as Vision & Change and Next Generation Science Standards emphasize the importance modeling as a core competency for STEM education generally and for training in life sciences, specifically. However, modeling in the college biology classroom comes with many non-trivial challenges. Instructors are confronted with diverse interpretations of what it means to 'model' and few coherent guidelines about 'what' students should model or how to evaluate modeling products. With few studies beyond K-12 learners, researchers are challenged to identify the mechanisms by which model-based skills develop and promote conceptual understanding in undergraduate learners.
Our past and current work is organized around two complementary objectives:
(1) to provide tools, examples, and strategies for incorporating models and modeling in undergraduate biology and aligning model-based goals for teaching and assessment.
(2) to conduct research that reveals (a) patterns in student thinking when learning with models, and (b) mechanisms used by students as they construct, reason about, and evaluate models of biological systems.
We developed an instructional strategy that uses conceptual modeling as a foundational activity and assessment intended to cohere and integrate studentsﾒ thinking about ﾓbig pictureﾔ ideas in introductory biology. We adapted Structure-Behavior-Function Theory (Goel, 1996) from Design Systems Engineering as a framework for aligning our curricular and assessment materials with research objectives in order to use a common set of language and metrics and all aspects of our instruction and analyses.
We conducted in-situ classroom experiments and clinical interviews to examine multiple hypotheses about how students construct and reason with models. Our studies examine (a) what constituents students identify as relevant to a biological system, (b) how students organize their thinking in order to represent a biological system, (c) how students evaluate alternative models of systems, (d) how student thinking changes over time, and (e) how students' model-based thinking compares to alternative, non-model representations.
Our research on students' construction of models in introductory biology has revealed several important findings that have implications for instruction:
(a) In systems requiring reasoning across scales, students tend to focus on macro-scale and/or visible system components. Micro-scale and/or invisible components and processes are often omitted or de-emphasized in terms of their relevance to understanding system function.
(b) Over a semester of model-based instruction, students' representations of biological systems progress toward parsimony. Changes in studentsﾒ models early in their learning are characterized by incorporation of new structures and connections, and improvements in their ability to describe system relationships. However, models built later in the semester suggest students continue to improve in their use of biological language, but without an associated increase in model connectedness/complexity.
(c) The effects of model-based instruction and development of model-based skills are not uniformly distributed, and may have the greatest impact on students who are under-prepared for college biology. In an analysis of model-based performance by achievement tritile, we observed that although performance increased for all groups and achievement gaps persisted, the margin of the gap narrowed considerably over a semester of instruction with the lowest-performing students experienced the greatest relative gain.
Our current and future work is directed at improving our understanding of the processes and mechanisms used by students as they construct, reason with, and evaluate models of biology systems. In addition, we are conducting an exploratory analysis to identify the constituents of biological systems thinking in order to determine whether model-based instruction and assessment can promote and reveal evidence of systems thinking.
Our model-based instruction (approaches, materials, and assessments) has been implemented in multiple courses at institutions throughout Midwest, and nationally, and has been shown to be feasible in large-enrollment courses (> 400 students). Our instructional tools and approaches are responsive to recent STEM education reports that identify systems and modeling as cross-cutting concepts and competencies necessary for achieving basic science literacy. We have developed and adapted tools and methodologies from disparate disciplines that facilitate qualitative and quantitative analyses that can inform us about the conceptual content of studentsﾒ representations, thereby promoting research about student learning. Our research suggests model-based instruction warrants further investigation regarding its potential to bridge achievement gaps for underprepared students, particularly for those underrepresented in STEM.
Project was designed for the purpose of addressing a specific challenge - how to quantify and characterize modeling proficiency in order to compare student performance at different points in time and/or across learning contexts. We adapted tools and approaches from other disciplines, including Design Systems Engineering and Network Analytics, in order to develop a core language and set of metrics that could be used for teaching and evaluating conceptual models constructed by students in college-level biology.
Dauer, J and TM Long. 2015. Long-term conceptual retrieval by college biology majors following model-based instruction. Journal of Research in Science Teaching. Doi: 10.1002/tea.21258
Bray Speth, E, N Shaw, J Momsen, A Reinagel, P Le, R Taqieddin, T Long. 2014. Introductory biology students' conceptual models and explanations of the origin of variation. CBE Life Sciences Education 13:529-539.
Long, TM, J Dauer, KM Kostelnik, JL Momsen, SA Wyse, E Bray Speth, and D Ebert-May. 2014. Fostering ecoliteracy through model-based instruction. Frontiers in Ecology and the Environment 12(2):138-139.
Dauer, JT, JL Momsen, E Bray Speth, SC Makohon-Moore, TM Long. 2013. Analyzing change in studentsﾒ Gene-to-Evolution models in college-level introductory biology. Journal of Research in Science Teaching 50(6): 639-659. Doi: 10.1002/tea.21094