Prompt Question: How do genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment?
Objective: Students will be able to construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment.
Materials: - Natural selection simulation activity sheets (one per student) - Pencils - Whiteboard or chart paper - Markers
Procedure:
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Introduction (10 minutes): a. Begin the lesson by asking students if they know what natural selection is. Allow a few students to share their understanding. b. Explain that natural selection is the process by which individuals with traits that are better suited to their environment are more likely to survive and reproduce, passing on those traits to future generations. c. Introduce the prompt question: “How do genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment?” d. Explain that today, students will be participating in a natural selection simulation activity to observe and analyze how genetic variations affect an individual’s survival and reproductive success.
- Natural Selection Simulation Activity (20 minutes):
a. Distribute the natural selection simulation activity sheets to each student.
b. Explain the rules of the simulation:
- Each student represents an individual organism in a population.
- Each organism has a specific trait (e.g., beak size, fur color) that can vary within the population.
- The environment will change over time, and certain traits will become more advantageous or disadvantageous depending on the environment. c. Instruct students to complete the activity sheet by making observations and recording data as they participate in the simulation. d. Allow students to engage in the simulation for about 15 minutes, making sure they understand the cause and effect relationship between traits and survival/reproduction.
- Analysis and Discussion (15 minutes):
a. Gather students back together and have them share their observations and data from the simulation.
b. Write the prompt question on the whiteboard or chart paper.
c. Guide students in constructing an explanation based on evidence by asking the following questions:
- What did you observe during the simulation? How did the environment change?
- How did the traits of the organisms affect their survival and reproductive success?
- What evidence from the simulation supports the idea that genetic variations of traits increase some individuals’ probability of surviving and reproducing? d. Write down students’ responses on the whiteboard or chart paper, emphasizing the use of academic vocabulary and cause and effect relationships.
- Conclusion and CER (10 minutes):
a. Explain that now that students have analyzed the evidence and discussed their observations, they will construct an explanation using the Claim-Evidence-Reasoning (CER) framework.
b. Review the CER framework with students:
- Claim: A statement that answers the prompt question.
- Evidence: Specific data or observations that support the claim.
- Reasoning: An explanation of why the evidence supports the claim. c. Model an example CER using the prompt question and evidence from the simulation. d. Instruct students to individually write their own CER using the prompt question and their observations/data from the simulation. e. Allow students to share their CERs with a partner or in small groups for feedback and revision.
- Wrap-up (5 minutes): a. Bring the class back together and invite a few students to share their revised CERs. b. Emphasize the importance of using evidence and academic vocabulary to support their claims. c. Summarize the main idea of the lesson: Genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment through natural selection. d. Encourage students to continue exploring and researching the concept of natural selection and its impact on genetic variations in populations.