Lesson 1: Step 1 | Plant A | Plant B | Prediction: starting population | Both plants’ populations will start at equivalent numbers. | Prediction: ending population | Both plant’s will reach equilibrium at the same time, unless one is dominant. Then the dominant plant’s ending population will optimize, while the other plant will die out. | | Starting population | 6,000 | 3,500 | Ending population | 10,000 | 0 |
Lesson 1:Step 2 | Plant A | Plant B | Herbivore A | Prediction: starting population | Will continue to prosper, but it’s ending population will be lower than that in step 1. | Will have more of a chance of surviving for a longer period of time. | Will grow with plant A | Prediction: ending population | Lower than that in part 1 | Higher than in part 1. Higher than plant A. | Will grow as plant A decreases. | Starting population | 5,256 | 3,700 | 1,312 | Ending population | 3,335 | 4,998 | 2,055 |
Responses to questions | Step 1 1. What assumptions does this model make about co-dominance as well as the general terrain of the ecosystem? That the more dominant species will prosper the most due to competition. The terrain’s conditions are suitable for only one plant to prosper. 2. Do you find one producer to be dominant? Why might one producer be dominant over another?Yes. Plant A was dominant. I think the reason is that Plant A was most suited for the terrain.Step 2 1. Does adding the herbivore establish a more equal field? Is one producer still dominant over the other? Why might one producer be dominant over another?Yes it did. Plant A is still dominant but not by as much because the rabbit eats it allowing Plant B to come through. 2. If the simulation included decomposers, how would your current results change?I think that both plants would do better and in turn so would the Herbivore. This being said I believe the ratios would be similar but with higher populations of each. 3. How do producer population numbers with the presence of an herbivore compare to the primary colonizer model?They are a lot different. This time both of the plant species survived due to the herbivore eating A and allowing B to establish itself. |
DATA TABLE: ECOLOGY
LESSON 2
Lesson 2:Step 1(X, , or ) | Plant A | Plant B | Herbivore A | Omnivore A | Top Predator | Prediction | | | | | | Simulation 1 | | | | | | Simulation 2 | | | | | |
Lesson 2:Step 2(X, , or ) | Plant A | Plant B | Plant C | Herbivore A | Herbivore B | Herbivore C | Omnivore A | Omnivore B | TopPredator | Prediction | | | | | | | | | | Simulation 1 | | | x | | | | x | x | | Simulation 2 | | | x | | | | x | x | | Modifications made | x | | | | | | | | |
Responses to questions | Step 1 1. Was your prediction correct? How did you arrive at your prediction? What differences were there between your prediction and the simulation? My prediction was partially correct: all of the organisms survived, but Plant B's numbers went down. Plant A still had more members than Plant B. I arrived at my prediction because it make sense that Plant A would decrease in number since there are herbivores eating it. The simulation showed that Plant A decreased in size at first, then remained constant, although there were still more Plant As than Plant Bs. Plant B increased in number, whereas the herbivores, omnivores, and the top predator all remained constant. 2. What would happen to this imaginary ecosystem if the producers were to die out? The other species would die out. 3. 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? The herbivores may have increased in number due to an stable level of food which would provide them with the nutrients they need to survive. The increase in omnivores may have been due to the same reason. The species that decreased in number were Plants A and B. First, these plants decreased in number significantly; however, they soon began to level off and become more stable. The initial decrease may have been due to the competition for resources and the introduction of herbivores. Later on, the two plant types may have developed some sort of trait, or they may have just produces a large amount of offspring, so that their levels became more stable. 4. Which populations would benefit the most from the presence of decomposers? If decomposers are introduced to the ecosystem, the organisms that would benefit the most would be Plants A and B. The decomposers would "recycle" all dead matter in the ecosystem and turn it into rich soil that plants can grow well in.Step 2 1. Was your prediction correct? How did you arrive at your prediction? What differences were there between your prediction and the simulation? No. I think they will be able to live together well. However, Some of the species did die out. For example, Plant C and both omnivores all died out after some time. 2. Were you able to modify the parameters so that each species survived? Explain how you decided what changes to make. I was not able to make all of the organisms live. I made all of them except for Plant A. To do this, I made all of the herbivores eat all types of plants. The omnivores ate all types of plants and herbivores as well, whereas the top predator only ate the omnivores. In this way, all of the organisms lived together well, although plant A died out after a while. 3. Which way does energy flow and how does eating an organism result in energy transfer? Energy flows from the producers up towards the top predator. When one organism eats the other, some of the energy stored in the prey is taken up by the predator. The amount of energy left in each trophic level is relatively small, however. Only about ten percent of the energy in one trophic level is available to the next. For Your Consideration 1. How does a natural ecosystem offer suggestions toward a more economical and eco-friendly human model?If humans followed the same methods as a natural ecosystem, then humans, the top predators, would not eat all of the other organisms in the ecosystem. When that happens, all of the organisms below them on the food web would die out due to hunting. If humans follow this model, then the organisms below them on the food web would all be able to survive. Furthermore, in an ecosystem, all of the diverse organisms depend on one another. In human life, we also need this diversity and interdependence to succeed as a species. 2. How do humans affect the greater food web? In this model, how could humans who do not live in the ecosystem still manage to alter the flow of energy within the web?Human intervention in the ecosystem, even though they do not live in it, can alter the food web. For example, hunting or the destruction of habitats can drive a species to extinction. This would lead to the extinction of several other species in the ecosystem, which would completely destroy the balance in the environment. |
