Lesson Plan Template: Learning Cycle (5E Model)
Learning Objectives: What will students know and be able to do as a result of this lesson?
Students should be able to explain how natural selection occurs, and understand how 4 different factors (overproduction, variation, competition, and environmental change) can cause selection to occur. They should be able to offer an example of each and explain how some organisms in a given population may be more likely to survive and pass on their genes to the next generation.
Prior Knowledge: What prior knowledge should students have for this lesson?
- Students should be able to discuss how Darwin formed his theory of evolution by natural selection and explain what he said about how species changed over time, specifically referencing the evidence Darwin used to form the theory.
- Students should know what an adaptation is, and be familiar with the Galapagos species and their adaptations.
- Students should know that a beneficial mutation is a change in the genetic makeup of an organism that leads to a specific appearance or function that may benefit the organism. They may not all have a clear understanding of genetics, inheritance, or DNA if evolution is taught before genetics, but it makes it harder to explain what is really happening between generations.
- Students should know that offspring inherit characteristics from their parents.
- Students should know that a population is a group of organisms of the same species, and that only members of the same species can produce offspring.
- Students must be comfortable working in groups.
- Students must be accustomed to working successfully in unstructured lab situations.
- Students should be familiar with lab reports.
- Students need to be able to use data tables and graph trends.
Guiding Questions: What are the guiding questions for this lesson?
- How can natural factors working on a population lead to change in a population over time?
- What does it mean that some organisms are selected by the environment to survive and reproduce?
Engage: What object, event, or questions will the teacher use to trigger the students' curiosity and engage them in the concepts?
Materials needed: PowerPoint presentation, Butterfly outline for each student, art supplies
1. Students will be given an outline shape of a butterfly and told to design the best butterfly possible in 5 minutes. A PowerPoint with student directions for each phase of this lesson is provided. A printable sheet of moths is also included.
This will be a very short amount of time, especially if the shapes are not cut first. However, keeping it to 15 minutes total should be just enough time for them to complete the Explore weblab assignment. If students need more time, then the two activities can be extended over two days. You can also have them work in partners, but it makes fewer moths and they are small for two kids to work on at once.
2. The students are then told their butterflies are out in the real world and at risk of predation. The students will be given 45 seconds to hide their butterfly in the room. Then a hungry bird comes and hunts for butterflies. This should take about 3 minutes total.
Depending on the number of students/ butterflies, the designated area for hiding should be fairly small. Students must be clear that they cannot hide underneath or behind any objects. You should also set an upper and lower height range depending on how high you want to stretch up or bend down. Make sure that their belongings are cleared out of the way.
You can hunt yourself, or can designate a student to be a hunter. If you are going to be the hunter (and you trust your kids enough), you might want to close your eyes while they put up the moths so it is not too easy for you to find them. You can also designate a student to be the hunter. He or she should be out of the room or blindfolded while the students are hiding the moths. I have also had teachers and administrators come hunting, and the kids are pleased with the celebrity guest stars, but it takes more effort to organize and takes longer.
3. Whole Group Debrief (5 min)
- What did you notice about the butterflies that got nabbed first?
The brightest, prettiest butterflies will probably go first. Some of them will survive due to luck and timing, which happens in nature too.
- What was different about the survivors?
They were better camouflaged, so they were harder for the predator to find. They survived until time was called.
- How do you think that relates to the way a species might change over time?
Organisms that are hardest to find are more likely to survive. If they survive, they might pass down the genes that helped them survive to their offspring. Then their offspring have an advantage, and number of organisms with the adaptation will increase in the population. Those without an advantage are more likely to die, and their traits die with them.
Explore: What will the students do to explore the concepts and skills being developed through the lesson?
Materials needed: Student laptops with shockwave installed, lab sheet
Students will explore the weblab simulation created by the Education Development Center, Inc. and programmed by MathResources, Inc. as part of Enlivening Genetics Education Project. They will complete the included worksheet that follows along with the simulations.
The questions go in order. It usually takes my advanced students about 30 minutes to complete. I let them work with partners.
The weblab uses Shockwave, and has been around a while. It can sometimes be problematic to get the permissions to install Shockwave on student computers. However, the simulation does a very nice job of going through natural selection and letting them play around with the different scenarios. If tech is a problem in terms of student access, I've done this as a whole group with a projector, still making them answer the questions on the worksheet to hold them accountable for the activity. If it won't work at all, the main ideas are covered in the other components of this lesson plan.
Explain: What will the students and teacher do so students have opportunities to clarify their ideas, reach a conclusion or generalization, and communicate what they know to others?
Materials needed: PowerPoint presentation, 11x17 paper for posters, art materials, animal reference pictures
1. Using the "Factors Leading to Natural Selection" section of the PowerPoint provided, the teacher will explain the four factors that contribute to natural selection, overproduction, variation, competition, and environmental change. Students should take down notes for the basic explanations, and go through how sea turtles illustrate how the factors might work on a population.
Overproduction is the hardest for the kids to understand. They confuse it with overpopulation. Overproduction means far more offspring are produced that can survive due to competition and limiting factors. Overpopulation occurs when a limiting factor is removed and more of those offspring survive than the system can support. If there is no variation, no selection can occur and it is simply a matter of luck who survives to pass on their identical trait. Without competition, everyone survives so no selection. Students should be clear about what organisms are competing for - often they are competing not to be eaten by something else. In an evolutionary context, competition occurs within the species to force selection. Competition with other species in a similar niche is part of ecology, and often leads to the extinction of one of the species. Environmental change does not have to be, and in terms of evolution has rarely been, related to human impact on the environment.
2. Students will create posters in groups illustrating the four factors acting on a population of their choice, and will be assessed according to the rubric below. Students will evaluate posters and will vote on which to hang in the room as a reference during the unit.
I only give the kids the class period for their posters. They always want more time, but on task groups do have enough time to create a good idea. I give them one tabloid size (11x17) piece of white paper, and provide art boxes. I also have field guides and books on animals to give them references for their illustrations, and ideas for populations. I don't let them use computers or phones because it eats up too much time, and I want them to think creatively. I also have them lay their finished work out (names on back) with a sticky note on the front, so that all of my students can vote on which posters they want to hang up on the wall. Then I post them and leave them up through the test. This makes them selective and critical about how well the poster reminds them of the factors, and is a good way for students to assess the relative quality of their work.
Poster Rubric (26 points)
- The population illustrates each of the four factors leading to natural selection realistically. (12 points possible)
- Explanation clearly shows how the factor is working on the population, makes sense, and is realistic. (3 points)
- Explanation shows how the factor works, but the scenario is not entirely clear or thoroughly explained. (2 points)
- Factor is included, but the explanation doesn't make sense. (1 point)
- Factor is not represented on poster (0 points)
- Text on the poster explains the factor appropriately (4 points possible)
- 1 point for each factor for at least a complete sentence explaining how the scenario relates to the factor.
- Pictures illustrate the factors at work (8 points possible)
- 1 point for each factor for at least some illustration in color representing the factor.
- 1 point for each factor if the illustrations drawn relate to scenario
- Each factor is written on the poster as a clear heading, large enough to read. (1/2 point each factor)
Make sure that you write with clarity of expression and show depth of thought, as you are not making the poster portion of the original assignment.
Elaborate: What will the students do to apply their conceptual understanding and skills to solve a problem, make a decision, perform a task, or make sense of new knowledge?
Materials needed: Powerpoint presentation, pre-prepared white and black "moths", matching background, forceps, blindfold, lab sheet.
1. Using the powerpoint provided, teacher will present the story of the peppered moth. Students will take notes and answer formative assessment questions during the discussion.
I include a slide on the difference between camouflage and protective coloration (like chameleons and cuttlefish who can change color to suit the environment) to emphasize that change occurs within a species, not within an individual. Individuals are born with or without an adaptation, and live or die accordingly. They cannot change to suit their environment. I also like to emphasize that the peppered moth scenario shows that selection can occur over a relatively short period of time, as long as an alternative variation already exists within a population, like the black morph. In the case of rapid environmental change where no favorable variation exists, most populations do not survive. Evolution takes a long time when you are hanging around waiting for a random mutation to occur.
2. Students will conduct a simulation of the peppered moth scenario using paper moths. They will collect and combine data sets for the class, and will graph their analysis. They will submit a lab report following the provided lab guide for evaluation.
- Preparation: Before the lab, prepare white and black paper moths and matching white and black backgrounds.
The moths need to be cut out and I laminated mine. I divide the class into two groups. Each group needs 100 white moths if they are going to have enough if every white moth survives. I also created a laminated background of 3 sheet long speckled white paper on one side, with black construction paper on the other for their forest. I have seen some labs that use hole punched dots on the same paper background as an alternative to the little moths I use.
- Step 1: Each lab group needs to start with a 3:1 ratio of light colored moths to the dark colored moth mutation and arrange them on the light colored background. Predator should not see placement.
They need to start with the light colored background facing up on their desks. I divide the class into two large groups to run the simulation.
For each round, they choose one student to be the predator. I let them change predators between each round. The forceps will be their beak, and they can only use the one hand to pick up the moths. With the forceps and the tiny moths it is not easy to pick them up.
Predator must be blindfolded or close his eyes while the other students have 5 seconds to spread out their initial moth population on the background sheet. Remind them that they can't hide them as they are testing coloration not craftiness. Make sure they record the initial population in their data tables.
- Step 2: The predator has 5 seconds to hunt as many moths as he can, using only the forcep "beak" to capture the prey.
If they spin the predator a bit, then another student needs to make sure to guide them to the table. It makes it more fun, but it is OK if they just close their eyes.
- Step 3: For every moth that survives, students add one more moth of the same coloration.
If they get all of the individuals of one variation in the round they need to add one to the population. They have to count all the moths for both phenotypes, and record the new population in the data table.
- Step 4: Repeat for two more rounds with the light background, and 3 with the dark background.
I have the two groups combine their data for the class so they have a better data set to graph.
3. Students use the following class period to complete the analysis and conclusions.
The background and the simulation should be completed in one class period, but they can't get the analysis and conclusions done. I usually give them the following class period to finish the lab report for submission. I let them work together to complete the work, but collect an individual report from each student. If they miss the simulation, they can get the data from a classmate and still complete the lab report.
Engage: After designing their moths and seeing the result of the hunt, students should be able to explain that some moths were easier to see, and were therefore less likely to survive.
Explore: While exploring the web lab, students will complete a lab sheet with comprehension check questions. Instructor will check for understanding throughout activity.
Explain: Students' groups will produce a poster, which will be evaluated according to a rubric. Students will evaluate posters and select the best to be posted in the room. Posters should illustrate each factor (variation, competition, overproduction, and environmental change) with a realistic example.
- During the initial presentation of the story of the peppered moth, students' understanding will be assessed through questions built into the Powerpoint presentation.
- Students will complete a lab report, which will be graded for accuracy.