In this lesson, students model the interactions between the plants and animals in an ecosystem by playing a collection of online games. They also experiment to see how the ecosystem responds to change, as when they increase the number of carnivores. By comparing how different ecosystems—rainforests, deserts, mountains, and mangrove swamps—respond to these changes, students will recognize the general patterns at work in any healthy ecosystem.
- One 60-minute class period
- Understand that all ecosystems require a balance of producers and consumers.
- Explain how and why changing the quantity of one resource in an ecosystem affects the system as a whole.
- Explain how the food eaten by most animals can be traced back to plants.
- Describe how food webs connect plants, animals that eat those plants, and animals that eat those animals.
- Predict how changes to an ecosystem will affect the ecosystem as a whole.
[Note: While these games do allow students to experiment with the ratios of producers (plants) and consumers (animals) in an ecosystem, they are not a complete representation of a fully functioning ecosystem or food web. For example, decomposers such as fungi play a vital role in returning nutrients to ecosystems, but they are not included in the games, nor are students able to alter the nonliving components of the ecosystem, such as sunlight, rainfall, and temperature. Many plants also depend on animals to disperse their seeds or pollinate their flowers, but these relationships also are not addressed in the games.]
Prep for Teachers
- Read through the entire lesson.
- Play each of the games at least one time to familiarize yourself with how it works and what happens when you change variables, such as the quantities of plants, herbivores, and carnivores in the system. Note the bubbles above each organism’s head along the bottom bar of the game screen: clicking on these will bring up a pop-up window with the name of the organism and visuals showing what it needs to eat.
- Bookmark the games on each student device.
- One computer or tablet per pair of student
- Jungle Jeopardy: An Ecosystem Game
- Feed the Dingo: An Ecosystem Game
- Mountain Scramble: An Ecosystem Game
- Make a Mangrove: An Ecosystem Game
- Ask your students, “Did anyone eat sunshine for breakfast today?” (You’re sure to hear giggling or a chorus of “No!”) Then ask for a few volunteers to say what they had for breakfast. Jot down their answers on the whiteboard.
- Review the items your students had for breakfast and ask how many of these items came from plants. (While eggs, milk, and meat can ultimately be traced back to plants in an animal’s diet, that isn’t the point of this discussion quite yet.) Students might easily recognize that orange juice comes from oranges and maple syrup comes from maple trees, but you might need to explain that the grains in items like pancakes, cereal, and bread come from plants such as wheat or corn.
- Ask your students what they think those plants might have had for breakfast. Explain that plants make their own food using the energy of the sun. Plants store this energy, and when we eat plants, we also are eating energy that came from the sun. We might not take bites of sunshine, but the energy we get from the foods we eat started out as sunlight shining on plants!
- Introduce the terms herbivore, carnivore, and omnivore. Herbivores are animals that eat plants, carnivores are animals that eat animals, and omnivores are animals that eat both plants and animals. Most people are omnivores—we eat a variety of fruits, vegetables, and meat or other animal products, such as eggs and milk. Spiders are carnivores—they eat other animals, namely, insects. Carnivores are sometimes called predators; your students may be familiar with this term as well. Grasshoppers are herbivores; they eat only plant parts such as grass and leaves. Ask students to propose a way for the sun’s energy to get from a plant to a spider.
- Explain that they will now play a series of online games that challenge them to keep a virtual ecosystem alive by monitoring the numbers of plants, herbivores, carnivores, and omnivores in the ecosystem for 12 virtual days.
- Divide students into pairs and assign each pair to a computer station or tablet. Assign each pair to a specific ecosystem, ensuring that each of the four ecosystems has been assigned to at least one student pair. Have students play one full game.
- When groups have finished, have a short discussion. Were they able to keep their ecosystems alive for all 12 days? What was hard about keeping the ecosystem alive? Did they notice any patterns or rules that explain how to keep the ecosystem alive? Talk about patterns in the context of plants, herbivores, carnivores, and omnivores.
- Have students play another round, keeping in mind any patterns they noticed between the numbers and types of plants and animals alive on each day. Discuss this round. Did the students follow any rules or patterns this time? If so, what were they? Did the rules or patterns they followed help them maintain a healthier ecosystem? Why or why not?
- Have students repeat step 3 in another ecosystem. Be sure that each ecosystem’s game is played by at least one student pair.
- Wrap up with a discussion about the collection of ecosystem games as a whole. Ask students if they noticed any similar patterns among the ecosystems. For example, what happened to each ecosystem if they added more animals than plants? What does this tell them about the makeup of a healthy ecosystem? Can any ecosystem survive if it has more animals than plants? Why or why not? Then, ask students to explain why plants are so important to healthy ecosystems. Circle back to the conversation about sunshine and energy from the beginning of the lesson. Be sure students understand that plants make up the basis of any ecosystem. This means that all the animals that live in an ecosystem, even the ones that eat other animals, depend on plants for their energy. Animals that eat other animals often eat animals that eat plants. A wolf, for example, may eat squirrels. Squirrels eat nuts, berries, and other parts of plants. Wolves then depend on plants, since they provide squirrels with the food they need. What might happen to the ecosystem if it had more carnivores than plants?
- [Optional] These games provide a great way for students to experiment with changing the variables in an ecosystem—a type of biological experiment that’s not easy to design! By playing these games, your students are modeling the interrelationships among the species in an ecosystem. If you would like to explore the interrelationships among plants and animals in greater depth, try one of the following:
- Give students the following rules to follow the next time they play:
- On day 1, add only plants
- On day 2, add only plants
- On day 3, add only herbivores (They can identify which animals are herbivores by clicking on the bubble above the organism; those that eat only plants are herbivores.)
- After day 3, ask students to make a prediction: what might happen if they continued to add only herbivores to the ecosystem? (The herbivores would likely eat all of the plants. Without a food source, the herbivores would then not survive.) Ask students what else might be important for keeping the ecosystem alive. If they need prompting, ask what might eat some of the herbivores, as well as what the herbivores need to eat.
- Have students make up their own pattern for adding organisms to the ecosystem, such as adding two plants, two herbivores, and one carnivore or omnivore every day. Experiment with the variables—what happens if they add more omnivores than plants and herbivores on consecutive days? All predators on another day? Have them make predictions for each set of variables they change. How would the changes affect the ecosystem? Why?
- Give students the following rules to follow the next time they play:
Have students work in pairs or groups to produce a skit, song, poster, or comic strip that shows how the sun’s energy flows all the way through an ecosystem, from a plant to a carnivore. Have students perform their songs or skits for one another, or, if they have produced posters or comics, have students present them to the class.
Next Generation Science Standards Correlations
Disciplinary Core Ideas
- LS2.A: Interdependent Relationships in Ecosystems
- LS2.B: Cycles of Matter and Energy Transfer in Ecosystems
- LS2.C: Ecosystem Dynamics, Functioning, and Resilience
Science and Engineering Practices
- Asking Questions and Defining Problems
- Developing and Using Models
- Using Mathematics and Computational Thinking
- Obtaining, Evaluating, and Communicating Information
- Cause and Effect: Mechanism and Explanation
- Systems and System Models
- Energy and Matter: Flows, Cycles, and Conservation