- Lessons > Food Web > Step 1
First you’ll run a less than “real-life” scenario. Choose only one organism from each trophic level and make sure that the food chain goes in a straight line from one trophic level to the next, i.e., Herbivore A eats Plant A, Omnivore A eats Herbivore A, and the Top Predator eats Omnivore A. Let Plant B survive on its own and see what happens. Predict whether each species will survive, and whether it will increase or decrease in number, as well as whether Plant B will survive to the end. Record your prediction in the Data Table and then run the simulation twice and record your data. Use X for “die out,” ↑ for “increase in numbers,” and ↓ for “decrease in numbers.” Take a Screen Capture of the end of your simulation.
Answer the following questions and record your answers in your Worksheet:
- Was your prediction correct? How did you arrive at your prediction? What differences were there between your prediction and the simulation?
- What would happen to this imaginary ecosystem if the producers were to die out?
- Did any of the species increase in number? What could account for this increase? Which species decreased in number and what might account for this decrease?
- Which populations would benefit the most from the presence of decomposers?
- Include your Screen Capture
- Lessons > Food Web > Step 2
Now try a more “real-life” scenario and experiment with what might happen in an ecosystem that is more like a web. This time click the “all on” button. The model shows who eats whom and the paths by which energy is transferred. Predict which populations will die out, increase in numbers, or decrease in numbers and record your predictions. Run the simulation twice and record the results in your Data Table. Then try to modify who eats whom in order to ensure the survival of all species and record what was changed in your chart. Take a Screen Capture of the end of your simulation.
Finally, answer the following:
- Was your prediction correct? How did you arrive at your prediction? What differences were there between your prediction and the simulation?
- Were you able to modify the parameters so that each species survived? Explain how you decided what changes to make.
- Which way does energy flow and how does eating an organism result in energy transfer?
- Include your Screen Capture