Data Tables: Ecology

DATA TABLE: ECOLOGY LESSON 1

Lesson 1: 100 step Plant A Plant B Step 1 Prediction: starting population 4500 6500 Prediction: ending population 4000 6000 Starting population 6114 3427 Ending population 10000 0

Lesson 1: 200 step Plant A Plant B Herbivore A Step 2 Prediction: starting population 10000 0 5000 Prediction: ending population 4000 3000 7500 Starting population 10000 0 0 Ending population 3333 0 2223

Lesson 1: Resetting of simulation Plant A Plant B Herbivore A Step 2 Prediction: starting population 3500 4000 2000 Prediction: ending population 3000 4500 2600 Starting population 5256 3700 1312 Ending population 3335 4998 2055

Responses to questions

Lesson 1 Q and A: 1. What assumptions does this model make about co-dominance as well as the general terrain of the ecosystem?

It assumes that only one or the other of the plant species will survive. There appears to be no co-habitation of the plants and that the terrain is only supportive on one plant species not both.

2. Do you find one producer to be dominant? Why might one producer be dominant over another?

Yes I found only one producer to be dominant – plant A. This might be the more dominant plant as it started out with a larger populace than plant B. Also it could be assumed that the terrain was not supportive of plant B for its survival.

Lesson 2 Q and A: 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 the addition of an herbivore allows a more equal field. Plant B becomes the dominant plant due to the fact the herbivore is opening up more room and resources (son, soil, water etc) for plant B to grow. In this instance Plant B was the dominant produce due to the herbivore eating Plant A and keeping its numbers down.

2. If the simulation included decomposers, how would your current results change?

Decomposers may change the results dependant on which of the produces benefits most from the food it produces. Therefore, whichever plant benefits the most will become the more dominant.

3. How do producer population numbers with the presence of an herbivore compare to the primary colonizer model?

The producer population is easily comparable due to the number of their populations recorded before and after the introduction of the herbivore. When there are no herbivores plant A is completely dominate allowing none of plant B species to survive. However, when the herbivore is introduced plant B becomes the dominant species after the 100 step mark when the simulator has been reset. When the simulator has not been reset plant B population is still extinct, so even with an herbivore introduced plant B still cannot establish any population.

Notes I reran the simulation for Lesson 2 and ran it at 200 steps and recorded the results. I did this to provide some data for the table in the Primary Connections variable table I will also be filling out for this experiment. I also did this out of curiosity to see if plant B could come back to life in one simulation and then to see what happens when both plants start in the ecosystem when the herbivore is introduced.