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### Computer Simulation of Randomness

Crystal Reed and Eri Koike

Langton's Ant

Through this experiment, we attempted to discover what the overall purpose of Langton's ant is through a series of hypotheses and experiments.

We initially hypothesized that perhaps the size of the roadblocks would influence how long it would take it to start creating what we thought the intended purpose was of the ant: to create a road. Through our experiments, where we changed the size of the shaded square around the ant, we found the following data:

While the bigger square had started creating the road at around 5,000 to 6,000 steps.

The biggest square had created an inverse road within the square at around 16,000 steps and had started a real road outside of the square at around 22,000 steps. It also had a strange pattern that wasn't previously observed of creating walls around the outside of the square before beginning to create the real road.

Therefore, we found that environment determines the results of the behavior and road blocks/environmental changes make the ant go off track for a while but it always returns to the intended purpose of creating a road. Since the ant is basically 4 simple programmed steps, we found that when there are specific ideal conditions around the ant, these instructions wille express themselves in the road pattern. We paralleled this ant experiment to the construction of our previous plant experiment by stating that perhaps if conditions and genes match up (such as right soil and light), it would reach its optimal condition of growing.

Wolf Sheep Predation

Through this experiment, we were trying to discover how variations in factors in an ecosystem can change and affect populations.

We found that it would be most effective to discuss population fluctuations through creating very extreme environments through the absence of a predator or a prey. We initially hypothesized that if we removed the wolves, the grass would disappear due to the overpopulation of the sheep and eventually the sheep would die off as well.

Through this experiment, we found that instead, there was a corresponding jump in amount of sheep and drop in amount of grass in the ecosystem due to the absence of predators (wolves), but the populations began to even out and ultimately neither died out.

On the contrary, when we removed the sheep from the ecosystem and only had wolves and grass, we found that the wolves quickly died out and the grass had a huge spike in population.

Our conclusion that if you remove an element of prey, you will greatly affect the remaining ecosystem, since there isn't nourishment and a balance in the environment. However, when we removed the predator, we found that it had much less of an effect. We found that perhaps the reason why some factors are more stable than others is because perhaps some animals (in our case the sheep) don't have to work as hard as others (the wolf). It also may have to do with the pace that certain preys (the grass) reproduce versus the sheep.