How Ph Affects Pillbugs

Conclusion

        Our initial hypothesis was the pill bugs would go to the more basic (7.5 ph) side, because their habitat is slightly more basic than water (aprox. 7.1-7.3 ph), thus the more basic side would be closer to their environment therefore more pill bugs may be attracted to it, and based upon the lab, our hypothesis was supported. When we put them at 0min there were 5 on either side, then at the first 30 seconds there were 2 on the more basic side and 8 on the more acidic side. This and during the 4-4.5 minutes were the only times the pill bugs preferred the more acidic side.  We hypothesize that the incident at 0.5min was most likely caused by the pill bugs reacting to their new environment, because from the first 0.5-1.5 minutes the amount of pill bugs on either side jumped from 5 (0min) to 2 (0.5min) to 5(1min) to 6 (1.5min) on basic, and for acidic it jumped from 5 (0min) to 8 (0.5min) to 5 (1min) to 4 (1.5min). So the higher amount of pill bugs could have been the cause of them exploring the new environment, however further tests need to be done in order to be accurate. Then on 2-3.5 minutes, the pill bugs stayed constant with 8 on the basic side and 2 on the acidic side. Next 4-4.5 minutes, was the last incident the pill bugs were seen more on the acidic side (4 basic-6 acidic), we are unsure of the reason for this, in order to be sure if it’s an outlier more tests are needed. During the rest of the timed recordings (5-10min), the pill bugs favored the basic side. From 5-6 minutes, there were 6 on the basic, and 4 on the acidic. Then from 6.5-7.5 minutes, there were 7 on the basic side, and 3 on the acidic side. Then at 8 minutes it went back to 6 on the basic side, and 4 on the acidic side. At 8.5-9 minutes there were 8 on the basic and 2 on the acidic. At 9.5 minutes it went up to 9 on the basic and 1 on the acidic, but then at 10 minutes it went back to 8 on the basic side and 2 on the acidic side. When averaging the data, there were 134 pill bugs on the basic side over 21 recordings averaging approximately 6.4 pill bugs. On the acidic side there were only 76 pill bugs over the 21 recording averaging approximately 3.6 pill bugs. Overall, the data seems to show that the pill bugs prefer the more basic side to the acidic side of the Petri dish, because they have a higher average on the basic side, and seemed to spend the most time there. This data means that the pill bugs we tested prefer a more basic environment. This could possibly be because they are more adapted to the basic ph environments and cannot survive (or it is less efficient energy spending) in the acidic environment, or perhaps the basic environment allows for better gas exchange than other environments, more tests should be done to validate these ideas. However, since this is a small sample size and the first test, our results can’t be said to affect all pill bugs, and there are changes that could help ensure accurate results. One key issue with the testing was that the filter paper used to create the basic/acidic environment was a bit too small to cover the entire petri dish. This created a problem when the pill bugs entered our artificial environment, because some would walk around the sides of the dish, and not actually on the filter paper, so that could have affected some of our results. More of a technical issue was that we didn’t test the common activities and movements of our pill bugs before we placed them in our basic/acidic environment, so we don’t know if their behavior was directly caused by ph, it could have been some other environmental factor, or behavioral patterns. So for future experiments we could increase the size of the population, pre observe our pill bug group, and also make the filter paper cover the entire flooring of the petri dish. Because of all these possible data issues, it would be important to repeat this process, and compare the data to see if the ph really affects pill bugs, and to strengthen the validity of our hypothesis.