Impact of pre-lab learning activities, a post-lab written report, and content reduction on evolution-based learning in an undergraduate plant biodiversity lab

Abstract

Background: Commonplace biodiversity labs in introductory undergraduate biology typically emphasize declarative knowledge. We contend that shifting these labs to emphasize evolution, higher-order cognition, and science reasoning would benefit student learning. Four factors that likely make evolution-based higher-order learning goals difficult to achieve in these labs are: the novelty and quantity of required declarative knowledge, the number of integrated concepts, the theoretical nature of evolution, and limitations on working memory. Thus, we propose that a model to shift learning from lower-order declarative knowledge to evolution-based higher-order integration in these labs would reduce overall lower-order content, increase time efficiency through hands-on pre-lab activities, and increase evidence-based reasoning through written post-labs that emphasize evolution-based higher-order integration. We tested this contention by comparing exam performances of students who did and did not participate in the redesigned lab. Methods: A new plant biodiversity lab design was implemented in an introductory undergraduate biology lab class. The lab class was a separate class from the complementary lecture class, but the content-oriented learning goals were similar between the lecture and lab. We compared achievement of students in lecture + lab to those in lecture only with a pre-assessment and a mid-semester exam which contained questions that were both related and unrelated to the plant biodiversity lab learning goals. Results: Students in 'lecture + lab' relative to 'lecture only' did not perform significantly different on the pre-assessment lower or higher-order questions. On the post-assessment, students in lab + lecture performed significantly better on knowledge questions that were unrelated to lab with an improvement of 5.9%. Moreover, students in lab + lecture also performed significantly better on lab-related knowledge questions and lab-related evolution-based integrative reasoning questions with a range of 6.3 to 11% improvement, compared to students in the lecture only group. Conclusions: The proposed framework was successful in improving student learning for both lower-order declarative knowledge questions and evolution-based questions involving higher-order integration of concepts. In addition, because students in lecture + lab outperformed students in lecture only on questions unrelated to lab content, our proposed model highlights the importance of multiple inquiry-oriented lab experiences in higher education.