Dissections of single species (e.g., fetal pig) are a common student learning activity in introductory biology courses. Such dissections demonstrate location of anatomical parts and provide dissection practice but provide less opportunity for student critical thinking, numeracy and demonstration of the scientific method. A comparative anatomy lab was implemented over two years at a small, rural, private, liberal arts college. Students dissected their choice of five vertebrate species, mastered the location, function and gross evolution of the digestive and cardiovascular systems, and analyzed intestinal length and heart mass among sets of species. Instructors and students reported significantly more collaboration and reflective learning than in other exercises. The comparative approach highlights several evolutionary trends and created testable data at an equivalent cost to previous fetal pig dissections. (Contains 2 tables and 1 figure.)