Bacterial Evolution

Activity Summary
Students use a non-pathogenic laboratory strain of E. coli to test bacterial evolution of resistance to common household antiseptics. The lesson emphasizes the speed with which populations of single-celled organisms can evolve and uses relevant examples, such as the increasing prominence of MRSA, to relate the activity to students’ lives. Students also have the opportunity to swab locations around the school and evaluate the bacterial growth that results. This lesson provides an excellent opportunity for class discussions and tie-ins with scientific articles.

Grade Levels
9-12

Learning Objectives
1. Draw and correctly identify the 3 primary shapes of bacteria
2. Explain the impact human actions, such as the over-use of antiseptics and antibiotics, have had on the evolution of antibiotic     resistant bacteria
3. Define evolution in his/her own words
4. Articulate the scale at which evolution occurs (populations evolve, not individuals)

Lesson Materials (view or download)
PowerPoint
Lesson Plans

Keywords
population, individual, selection pressure, macroevolution, microevolution

Last updated: 3/5/2015