Evolutionary medicine is a growing area of research and practice; however, it is not widely discussed in introductory biology courses. Because of the interest in human biology, using evolutionary medicine is a great way to hold students' interest, placing topics in context, making the subject of evolution relevant. Too often students lose interest in learning about evolution because they think it is not pertinent. The pedagogical technique of using case studies in the classroom engages students in a way that will grow their understanding of topics, in this case evolution, as well as helping students with critical thinking and process skills, growing their scientific literacy.

The following case study is appropriate for an introductory biology course that focuses on evolution, an AP biology course, or an introductory evolution course for undergraduates. The case focuses on the evolutionary perspectives of what might be causing human ear infections, as well as the role of beneficial species of gut bacteria in maintaining a healthy immune system. It is advantageous for students to know about natural selection and coevolution before using the case study.