Using Student Doodles to Introduce the Concept of Evolution and Natural Selection
Lesson 2 of 11
Objective: Students will be able to define evolution and describe the process of natural selection using classroom generated examples/data.
Last spring, I used this activity to introduce the concepts of evolution and natural selection. I chose not to start off with an announcement or agenda item at the start of class about our work plan for the day. The elements of novelty and surprise added to the engagement and relaxed spirit of the learning environment and conversation at a time of year during which students report high levels of stress and anxiety concerning school performance.
Students were able to figure out the basics of our concept very early on and yet they were highly engaged in both the creation of their doodles and the discussion surrounding our generations of doodles throughout the class session. This was a great way to engage student's curiosity and creativity in a way that made it easier for them to build in our science vocabulary as we progressed throughout the unit.
- Note: This lesson is based upon Helen and Truman Young's article, “A Hand-On Exercise to Demonstrate Evolution by Natural Selection and Genetic Drift" in American Biology Teacher 65.6 (2003): 444-448.
I am excited to hear about your students impressions of and classroom experiences with this activity!
1. As students enter the classroom, hand out highlighters/markers and 5-6 sheets of paper. Tell students they have 2 minutes to copy the animal drawing I have posted on the front whiteboard.
- Note: The organism you choose to draw and post each class period can vary and is not important so long as it is something the students can easily draw, such as a fish.
2. After the timer goes off, ask students to hold up their fish drawings. Walk around the room and choose one from the group with as much dramatic pause as they can stand! Don't tell students what criteria you are using in order to make you choice
- Note: Expect lots of giggling and murmurs from the room as you walk around! My reflections that follow provide some options for you to choose from or build upon.
3. After choosing a drawing from the student group, take the first drawing down from the whiteboard and post the second one collected from the group. Ask students to copy this drawing as best they can in 2 minutes.
4. Repeat this process for 5-6 generations depending upon the time and conversational cues of the group.
- Note: You will hear all kinds of spontaneous conversations to happen concerning how fish are being chosen for the next round of drawings--I try not to confirm or comment until after our activity is over.
5. Once you have accumulated 5-6 drawings, post them up on the board in chronological order for students to view and analyze as a group. At this point, your engaged class discussion can begin.
Students will be highly engaged in your classroom discussion focusing on the question:
What happened to our fish population?
The role of the teacher guiding this discussion is to prompt students with questions and elicit/document on the board multiple responses so that the following big ideas come through:
- The fish population changed over each subsequent generation.
- Although there was a template to draw from, there were variations/differences between the fish pictures that each student drew.
- There was some reason/method to which pictures I chose each generation.
1. Start by asking students to share their observations about the fish population based upon the drawings posted on the board. Bring in comments by students that you might have heard as you chose fish throughout the activity as they become relevant to our discussion. You can either have students popcorn out their answers or utilize the spokesperson protocol.
2. As students volunteer and build upon each other's answers so that the points listed above are established by the group, introduce and relate major natural selection/evolution basic terms: evolution, variation, adaptation, and natural selection.
- Note: I've included the powerpoint for this unit as a resource here in case it might be of some use to you and your students and is based upon our district adopted textbook, Biology: Exploring Life by N. Campbell et. al. and published by Prentice Hall.
- In general, I do not go through ppt presentations slide-by-slide and instead highlight a few slides in class as part of larger class discussions and activities. Students tend to use ppt presentations as a resource to assist them in navigating our high level textbook at home and to prioritize, connect, and review concepts within a specific unit. Based upon our classroom conversations and observations, I then tailor my use of this resource to meet the needs of the students. For this discussion, slides #2 and 21 are most relevant.
1. After reviewing the basics of natural selection in relation to our big concept terminology (evolution, natural selection, variation, adaptation), you can begin to relate the content area work to the world we live in.
2. Ask students if they can think of any examples of natural selection happening today that impact us and record them on the board using the spokesperson protocol.
3. Briefly introduce the idea of antibiotic resistant bacteria and show a nine minute video clip from the PBS evolution website called "Why Does Evolution Matter Now?" concerning multi-drug resistant tuberculosis and the evolution of more/less virulent cholera strains in relation to water supply quality.
4. Depending upon the time available, group dynamics and discussion up to that point, now it is time to either:
- Give students a viewing guide to discuss and answer in writing with their small groups with time allotted for a larger group share-out of ideas as a starter activity during the next class session.
- Utilize viewing guide discussion questions as prompts for a large group discussion at the start of the next class session.