question archive BIO 102 Lab: EcologyBuilding an Ecosystem Access the following website: http://www
BIO 102 Lab: EcologyBuilding an Ecosystem Access the following website: http://www
Subject:BiologyPrice: Bought3
BIO 102 Lab: EcologyBuilding an Ecosystem
Access the following website: http://www.learner.org/courses/envsci/interactives/ecology/index.php
Click "Open Simulator". Currently, Plant A and Plant B are in the ecosystem. See what happens when you click "Run".
1) Record the number of individuals for Plant A and Plant B at each of the days: (You will need to move your pointer over the point on the graph to see the number of individuals at that time unit.)
1
2
3
4
5
6
7
8
9
10
Plant A
Plant B
2) What is the earliest time that Plant A hit 10,000 individuals?
3) When did Plant B become extinct in this ecosystem?
4) Keeping in mind that there are only two species of plants in this ecosystem (not animals), which of the following might be a reason that Plant A can outcompete Plant B?
a. Plant B is eaten by more animals than Plant A
b. Plant B has larger leaves than Plant A
c. Plant B is shorter than Plant A
d. Plant B is not poisonous to animals and Plant A is poisonous to animals
5) Change which two plants are in the ecosystem and see what happens. (Be sure to click "Reset" before you click "Run" with the new plants.) Can you get two plants to coexist without involving any other species? If so, which two plants? If not, why not?
Reset the simulator. Click on the rabbit icon (Herbivore A) and choose for it to eat Plant A. Also, have Plant B in the ecosystem (but no other organisms). Run for 100 days.
6) Which plant is dominant in the ecosystem (more individuals) after 100 days? Explain how the rabbits affect this plant being the dominant plant species in the ecosystem.
Look at the graph between Day 1 and Day 3.
7) Of Plant A, Plant B, and the rabbits, which population(s) is increasing?
8) Of Plant A, Plant B, and the rabbits, which population (s) is decreasing?
9) Explain the interactions between these three populations that cause these increases and decreases.
Look at the graph between Days 11 and Day 14.
10) Of Plant A, Plant B, and the rabbits, which population(s) is increasing?
11) Of Plant A, Plant B, and the rabbits, which population (s) is decreasing?
12) Explain the interactions between these three populations that cause these increases and decreases.
Food Webs
Reset the simulator. Choose one producer species, one herbivore species, and one omnivore species. Make them connect in a single line. (For example, the herbivore eats only the plant, and the omnivore eats only the herbivore.) Run the simulation for 100 days.
1) Which population is the largest (has the most individuals)? Does this make sense? Why or why not?
Without adding any new species to the ecosystem, try to adjust what eats what to make the population of omnivores increase.
2) When the population of omnivores increases, what population(s) decreases? Why does that population(s) decrease?
Reset the simulator. Click "All On". You will see the food web of what eats what.
3) Before you run the simulation, make a prediction about which populations you think will survive the best and why.
4) Run the simulation for 100 days. Record below which populations became extinct in the population and at what time unit they became extinct.
5) Hypothetically, if you wanted to modify the ecosystem so that all three plant species survive, what changes should you make? How would these changes help all three plant species survive?
6) Try the modifications you suggested in the previous question. Are they successful in having all three plant species survive? Why or why not?
Introduced Plant Species
1) Reset the simulator. Create an ecosystem with Plant C, one herbivore that eats only Plant C, and one omnivore that eats only the herbivore. Run the simulation for 100 days. At about what day do the populations in this ecosystem become stable?
2) Reset this ecosystem, and add in Plant B, but do not change anything else. Run the simulation for 100 days. How did plant B affect the other three populations in the ecosystem? Explain why it had this effect.
Loss of a Top Predator
1) Reset the simulator. Create an ecosystem with Plant A and Plant B, and Herbivore A (eating both plants) and Herbivore B (eating both plants). Also, add in the Top Predator that eats both Herbivore A and Herbivore B. Run the simulation for 100 days. Explain how the Top Predator affects the population of Plant A.
2) Remove the Top Predator and run the simulation for 100 days. Explain what happened to the population of Plant A and why the loss of the top predator caused that effect on the Plant A population.
