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The cooperative cows died out at a moderate reproduction cost (54), though at first it seemed like the greedy cows would die out. The cooperative cows died out even after lowering or increasing the reproduction cost as well as lowering stride length. Even after increasing the max grass height, the greedy cows neared extinction before their population shot back up and the population of the cooperative cows declined until they died out. There didn’t seem to be a situation that was beneficial for the cooperative cows in the long term.  We had expected to find that the cooperative cow population would survive longer than the greedy cows, even if initially they had lower numbers. There still may be a situation in which the greedy cows die out, but it appears that cooperation provides no long term benefit to survival in this model. This computer model seems to be useful for understanding the relationship between cooperation and resource availability, but there still could be other variables that would promote cooperation in cows that are not included in this simulation.  However, there still is the possibility that there never is an advantage to cooperation or altruistic behavior and so using a computer model has given us reason to reevaluate our assumptions about cooperation.

One of the simulations we had the most difficulty understanding and in successfully manipulating the variables was the Simple Birth Rates model. At first we attempted to change the blue and red fertility rates, but found that the two fertility rates had to be the same or else the population with the lower fertility rate completely died out. We then altered the carrying capacity, but still found that if there were different fertility rates one group would always die out.  Even though this was not a very complex model, we thought the results showed the delicate balance between the coexistence of two populations. Practically speaking, we don’t see any evidence of this in our real world experiences, but perhaps this phenomenon occurs more slowly than we are able to observe.