Understanding Randomness and its Impact on Student Learning: Lessons Learned from Building the Biology Concept Inventory (BCI)

Abstract

While researching student assumptions for the development of the Biology Concept Inventory (BCI; http://bioliteracy.net), we found that a wide class of student difficulties in molecular and evolutionary biology appears to be based on deep-seated, and often unaddressed, misconceptions about random processes. Data were based on more than 500 open-ended (primarily) college student responses, submitted online and analyzed through our Ed's Tools system, together with 28 thematic and think-aloud interviews with students, and the responses of students in introductory and advanced courses to questions on the BCI. Students believe that random processes are inefficient, whereas biological systems are very efficient. They are therefore quick to propose their own rational explanations for various processes, from diffusion to evolution. These rational explanations almost always make recourse to a driver, e.g., natural selection in evolution or concentration gradients in molecular biology, with the process taking place only when the driver is present, and ceasing when the driver is absent. For example, most students believe that diffusion only takes place when there is a concentration gradient, and that the mutational processes that change organisms occur only in response to natural selection pressures. An understanding that random processes take place all the time and can give rise to complex and often counterintuitive behaviors is almost totally absent. Even students who have had advanced or college physics, and can discuss diffusion correctly in that context, cannot make the transfer to biological processes, and passing through multiple conventional biology courses appears to have little effect on their underlying beliefs.

A participatory learning approach to biochemistry using student authored and evaluated multiple‐choice questions

“…Biological science students, in particular, have demonstrated misconceptions in tracing matter [38], glucose as a fuel [39], and randomness [40]. The process of understanding and analyzing student misconceptions seems to involve at least four steps: 1) Uncover and identify the misconceptions; 2) develop a diagnostic instrument to test for the misconceptions; 3) implement teaching and learning strategies to remedy the misconceptions; and 4) assess the efficacy of the remedial strategies.…”

Exploring the influence of plant and animal item contexts on student response patterns to natural selection multiple choice items

“…Research indicates that students struggle to understand the role of random processes in multiple areas of science (Ferrari and Chi 1998;Odom and Barrow 1995), and commonly attribute a goal or purpose to inanimate objects. In that sense, students are challenged to think about new traits as arising due to multiple, random genetic processes, such as recombination of genes through sexual reproduction, gene shuffling and random mutations in genetic sequences (Garvin-Doxas and Klymkowsky 2008). Part of the challenge to students' understanding is the fact that new mutations are not necessarily beneficial, but may also be deleterious or have no effect on an organism's phenotype (Muller 1932).…”

A Combination of Hand-held Models and Computer Imaging Programs Helps Students Answer Oral Questions about Molecular Structure and Function: A Controlled Investigation of Student Learning

“…Our experience with student interviews leads us to heartily concur with the BCI developers' conclusion that "Listening to a student explaining ideas in a relaxed, face-to-face setting is one of the most effective means for coming to an understanding of what is "inside" students' heads, what they really mean when they select a particular distracter, how they interpret questions, etc." (Garvin-Doxas and Klymkowsky, 2008). Educational research approaches and the resulting data are often messy but can lead to fascinating insights, especially when you take the time to sit down and have a good conversation with your students.…”