Armadillidiidae – Roly Polies!

2010/10/26
By Ms Baker

The 9th grade biology students have been studying the behavior of the common pillbug, Armadillidiiadae vulgarae.  This terrestrial crustacean is affectionately known as a roly poly for its defensive behavior seen below.

Photo source: Benjamint444, Wikimedia Commons

Pillbugs hide in dark, damp places during the day and are active at night; Photo source: C Young Photography

In their lab, students have been placing pillbugs into the observation chambers below.

In their first experiment, students set up one side of the container with wet filter paper and the other side with dry paper to test the environmental preference of the pillbugs. In their second experiment, students designed their own experiment to test the behavior of the pillbugs.  Example experiments included low pH vs high pH, warm vs cold, rough vs smooth, and light vs dark.

Students, record your lab results below.  In your summary, please include whether or not your data showed a clear preference for the wet/dry side in experiment 1 and what preference your data shows in experiment 2.  If there is no clear preference, please state “no clear preference”.

  • Alice

    The experiments done in class today on pillbugs, commonly known as roly polies, were very interesting. In the first experiment that tested whether pillbugs preferred wet or dry environments, my group came across some fascinating data. After recording the number of bugs on each side of the container every 30 seconds for ten minutes, it was clear that the pillbugs preferred wet environments over dry ones. The majority of the pillbugs remained on the wet side of the container during the ten-minute period. On average, there were about 7 pillbugs on the wet side of the container every 30 seconds, compared to the average of about 3 pillbugs on the dry side of the container.
    In the second experiment today, my group decided to test whether pillbugs preferred environments with higher or lower Ph levels. My group used the same container that was used in the first experiment, placing a few drops of Potassium Hydroxide on the filter paper on one side of the container and a few drops of Hydrochloric Acid on the other side of the container. After placing 5 pillbugs on each side of the container, we proceeded to record the number of pillbugs on each side of the container every 30 seconds for ten minutes, as we did in the first experiment. It became clear to my group that the pillbugs remained on the side of the container with the Potassium Hydroxide, which has higher Ph levels, rather than the side with Hydrochloric Acid, which has lower Ph levels. On average, there were about 7 pillbugs on the side of the container with the Potassium Hydroxide every 30 seconds, compared to the average of about 3 pillbugs that were on the side of the container with the Hydrochloric Acid.

  • Sara

    Wet/Dry Experiment

    After several trials and many observations were made I have come to the conclusion that there is no clear preference on which side the pillbugs prefer. It seemed as if the pillbugs followed each other around and it didn’t matter to them if the side was wet or dry. They migrated from each side almost every one minute and thirty seconds. This makes my hypothesis incorrect; I stated that if there is one wetside and one dry side then the pillbugs will migrate towards the wetside. The pillbugs actually have no preference over any of the sides.

    In our second experiment we decided to do the smooth vs. rough surface. My hypothesis was: If one side is covered with rough surface and another is covered by a smooth surface then the pill bugs will migrate towards the smooth side because it will be easier for them to move around.

    Overall, my hypothesis was correct because once one pillbug migrates to the rough side another follows but eventually they would move back to the smooth side. Every so often the same thing would happen one pillbug would migrate towards the rough side another would follow then they would migrate back to the smooth side. In this experiment i believe that the pillbugs preferred the smooth side although at some points they migrated towards the rough side most of the time they would migrate back. If I could I would actually do about 10 more trials just to make sure of this because the last trial ended with a more amount on the rough side. I think it would be important to find out if the pillbugs would then return to the smooth side. Overall, the pillbugs preference was the smooth side.

  • Jessica K.

    Dry vs. Wet Results:

    During the duration of 10 minutes, I recorded how many isopods were in each chamber at 30 second intervals. After taking an average, the were usually about 4 isopods. My data shows that isopods prefer dry areas better then wet areas so my hypothesis was incorrect. My hypothesis was that the isopods would have a preference to the damper side because from personal experience, I knew that isopods can be found under moist rocks.

    Darkness vs. Light results:

    As in the previous experiment, I recorded data at 30 second intervals for a 10 minute duration. However, this experiment tested whether the isopods had a preference for lighter or darker areas. My hypothesis was proven wrong again because according to the averages ( there were typically about 3 isopods on the lighter side and about 7 isopods on the darker side), the isopods had a preference to the darker side, or they were negatively phototactic. Due to the results of the previous experiment, my hypothesis was that the isopods would prefer the light area because wetness is more commonly associated with darkness and if the isopods prefer the dry land, they would prefer light land, as well.

  • Emily

    In the first experiment performed by my group, the pillbugs should a very clear preference for the wet side. The average number of bugs that stayed on the wet side was around 7, and the average number of bugs on the dry side was approximately 3. My hypothesis was proved incorrect because I erroneously believed that the bugs preferred dry areas, as I have usually found them in grass or on concrete. However, when performing the experiment, it was quite obvious that the bugs favored the damper side of the container.
    While doing the second experiment, the pillbugs showed a pretty evident preference for the side of the container with potassium hydroxide. The average number of bugs that stayed on the side with potassium hydroxide was around 7 and the average number of bugs that were on the side with hydrochloric acid was around 3. The bugs clearly preferred the side with potassium hydroxide.

  • Molly

    Just like Alice mentioned for the first experiment, my group completed the same procedure. The only difference was our results were varied, and we did not have an overall conclusion. Throughout our procedure, we recorded about an equal number of pill bugs on each side, but that number deeply fluctuated. For the first five minutes of the ten minute time period, our results varied from an equal number of pill bugs on each side (5 on the dry side and 5 on the wet side) to only 3 on the wet side and 7 on the dry side. Although only 1 more pill bug traveled to the wet side after this time trial, the results stayed around the same numbers. The only major change was that at the ten minute mark we recorded only 2 pill bugs on the wet side and 8 on the dry side! My group might tentatively conclude that the pill bugs prefer a drier environment, but granted this was only our first trial of recorded data. We might have used too much water and the environment could have been too wet for the pill bugs to make a clear decisive preference.
    In our second experiment, my group chose to a different procedure than Alice’s group. We tested the effect of a dark environment compared to a light environment. Like in Alice’s experiment, my group used the same plastic chamber, the same number of pill bugs or isopods (10), a stopwatch, a sorting brush, tinfoil (used to create a dark environment) and a new observation sheet. We copied the same chart down in our notebooks to record our results. Similarly to the previous experiment we placed 5 pill bugs on each side of the plastic chamber. Next, we quickly had to close the lids of each side of the chamber and as a group secured a piece of tinfoil over the lid of one of the chambers. We started our stopwatch, and at each 30-second interval recorded our data for how many pill bugs were on each side of the chamber. At first the data remained around the same numbers like in our first experiment, but by the end we reached a clear, tentative conclusion. At 6:30, there were 9 pill bugs on the dark side of the chamber and only 1 on the light side of the chamber. After this time trial, the numbers did not change greatly and by the last 2 trials there were either 0 or 1 pill bugs left on each side of the chamber. We reached a clearer conclusion than in our first experiment where pill bugs clearly prefer darker environments.

  • Monica

    Todays class experiment on pillbugs, also known as Ispods and commonly known as roly pollies, were intriguing. In experiment one, pillbugs were being tested to see if they prefer either wet or dry environments. My group collected very interesting information. There was a total of 10 bugs, 5 on each side of the container. One side of the container was wet, while the other one was dry. The data was recorded in 30 second intervals, with a total of 10 minutes. This meant that there would be 20 trials. With my groups pillbugs, it was clear that they favored the dry side, which proved my hypothesis wrong. On average there was about 4 pillbugs on the wet side, and 6 pillbugs on the dry side of the container every 30 seconds.

    In the second class experiment that was performed today, my group tested wether pillbugs preferred either dark or light environments. Unlike the first experiment, both sides of the container were dry, but the difference this time was that one side was covered with tinfoil, creating a dark environment, while the other was not which kept a light environment. There were still 10 pillbugs being used, and the data was recorded in the same process, 30 second intervals over a span of 10 minutes. The data showed that the pillbugs preferred the dark side, which again proved my groups hypothesis wrong. The thinking behind our hypothesis of that the pillbugs would prefer the light side is based off of our conclusion of the first experiment. In the experiment before, the bugs favored the dry side which correlates to dryness. The wet side correlates with darkness and the majority of the pillbugs did not favor the wet side, which made us think the way we did. As we recorded more and more data it became clear that the pillbugs preferred the dark side. On average there was 7 pillbugs on the dark side, and 3 pillbugs on the light side every 30 seconds.

  • Dan

    After spending 20 minutes retyping my observations and doing the Activity A2: Orientation behavior, I saw questions most unexplained and realized I did not need to do them…

    Anyway, my group (Zach and I) tested the effect of temperature on isopods. As it turns out, isopods are strongly opposed to heat, contrary to my belief which was that the reason the isopods could be found under things, is that it was an insulated environment. We performed our experiment by placing a heating pad under one half of the chamber and a towel (so that the chamber was on even ground) under the other. As we placed 5 isopods on each side, we started to notice little difference besides the fact that some had trouble getting off of their backs. After about 2 minutes the isopods began to exhibit a dislike to the heat. They ventured out to the heated side, but soon fled to the cool side. 4 on the heat soon turned to 2 on the heat, then 1, and finally zero. at 10:00–>16:00 the results were predominantly 0 (heated) and 10 (unheated) only twice going back to 1 and 9. Those who did go onto the heated side, ran quite fast as if it was very uncomfortable to be in, some even stood on the backs on others (and stayed there even as the carrier walked around) in order to escape the heated floor. It became clear that pillbugs DO NOT like the heat.

  • Deirdre

    In contrast with Alice’s Experiment 1, my group’s Isopod results seemed to show that the bugs preferred the dry side over the wet side. After analyzing our results further by averaging the amount of bugs that preferred dry and wet environments, the average of Isopods who enjoyed dry environments was only 0.2 higher than Isopods who enjoyed wet environments. Since this has only been one time testing the Isopods, I’d say there is not concrete evidence that the bugs like dry or wet environments.
    In our second experiment, my group tested to see if the Isopod’s would like rough or smooth surfaces better. After placing a rough terrain on one side of the tray, results became obvious that the bugs liked the smooth terrain better.

  • Zach

    The purpose of the two experiments were to test the isopods behavioral skills and the effectiveness of sensing two different environments. The first experiment examined the preference of a wet environment versus a dry environment. To perform the experiment, one half of the chamber (which holds 10 isopods) was covered in water coming from a pipette. The other half was kept dry, and therefore that was the control of the experiment. The data was recorded at 30 second intervals for 10 minutes. The number of pillbugs varied from time to time, but eventually, all the pillbugs moved to the wet environment, which proved my hypothesis correct. The following represents the average data of experiment #1:

    Avg. Number of Bugs on Wet Side – approximately 7 isopods
    Avg. Number of Bugs on Dry Side – approximately 4 isopods

    In a difference from the previously listed experiments, the second experiment consisted of testing the preference of a hot or cold environment. Both sides of the chamber were dry, but one half was placed on a heated pad while the other half rested on a table. The process of collecting data was similar to the first experiment, but the amount of time in which the experiment was run was increased by 6 minutes. Therefore, data was collected at 30 second intervals for 16 minutes. The following represents the average data of experiment #2:

    Avg. Number of Bugs on Hot Side – approximately 2 isopods
    Avg. Number of Bugs on Cold Side – approximately 9 isopods

    Surprisingly, my hypothesis was proven false. After the data was collected, the data showed that the amount of pillbugs that favored the hot side was a huge difference than the amount of bugs on the cold side. After more research on the topic, it was shown that pillbugs preferred to live under damp environments such as under varying sizes of rock, underground, or on moist leaves. In conclusion, we can conclude tentatively that isopods prefer the cooler side than the warmer side.

  • Aurora

    Unlike what we predicted in our hypotheses, the average number of isotopes seemed to favor the dry side as opposed to the wet side. Performing only one trial throughout 10 minutes, I would agree with Deirdre in saying thats this evidence is not enough to conclude that the bugs definitely like the wet surface over the dry surface. To improve this experiment, I would have performed more trials with a greater amount of isotopes.
    In the second experiment, we tested if the bugs had a preference to a smoother or rougher surface. To complete this experiment, we used the same amount of isotopes, but this time we were able to have more trials. This made our group’s conclusions clearer in that they favored the smooth terrain rather than the rough surface.

  • Cartland

    Since the start of the experiment, there were five Isopods on each side. Our group wrote down the observations every 30 seconds. And I got different numbers of Isopods on each side every time, but there were no zero on neither wet side or dry side. There was at least one Isopod was in one of the side. From my data, I got a conclusion that the Isopods are most likely to go to the wet side. But it is pretty strange, because the Isopods live on the land, why did they choose the wet side? My guess for this scene is that the Isopods are suitable to the environment, so they can adjust themselves to the environment very quickly.

    Our second experiment is about the PH. We have the Potassium Hydroxide on the right side which is the low PH(3 or 4), and we have the Hydrochloric Acid on the left side which is the high PH(10 or 11).And we also start the experiment with five Isopods on each side. And we wrote down the movement of the Isopods every ten seconds. Then though the observations, I find out that the Isopods are most likely to move to the Hydrochloric Acid side rather than Potassium Hydroxide.And I guess it might be the alkaline solution is more comfortable to them then the acidity.

  • Andrea

    Wet and Dry Experiment
    My hypothesis was that the pill bugs would gravitate and stay to the wet side because they are commonly found in moist soil. But the results in our experiment were very mixed, so we concluded that the pill bugs did not have a preference. I agree with Aurora because we there is not enough evidence to support the experiment. If we were going to repeat the experiment, I would add more isopods and more 30 second trials.
    Smooth and Rough Experiment
    Our next experiment is testing whether or not pill bugs preferred a smooth verses a rough surface. One side was covered in a piece of wired mesh and the other side didn’t have anything. Our hypothesis was that the pill bugs would all go to the smooth side and stay there because the smooth surface is easier to walk on. Most of the isopods stayed on the smooth side and went back and forth between both sides of the petri dish. It was until the very last trial that there were more pill bugs on the rough side.

  • Leyla

    My hypothesis was that the roly polys would prefer the dry side to the wet side. Our results were that there were more roly polys on the wet side six times, more on the dry side seven times, and an even number on both sides eight times. On average, there were 5.3 isopods on the dry and 5.2 on the wet. Therefore, we came to the tentative conclusion that the roly polys have no clear preference, because the numbers were extremely close. In addition, the roly polys seemed to simply follow each other around very often.
    For our second experiment, my group decided to do the rough and smooth experiment. We put a wire sheet on one side of the petri dish, and a wire sheet under the other side so that they looked the same but one was smooth. This experiment was considerably clearer than the other, because there were more isopods on the smooth side in all of our 19 trials with the exception of one. There was an average of 6.8 isopods on the smooth side and 3.4 on the rough side. This fit with our group’s hypothesis.

  • Gurk

    The first part of my experiment with the wet and dry side, my hypothesis was that the isopods would go to the wet side because the isopods are mostly found in moist area’s. But my experiment resulted in 96 for wet side and the dry side 112 isopods. So clearly my hypothesis was wrong.

    The second experiment was to see if the ispods will go to the rough side or smooth side. My hypothesis was that the isopods will chose the rough side over the smooth side, because the rough side could help the ispods to have a grip and, move up and down.And my outcome for the twenty two trials for the rough side was 147 isopods, and for the smooth side was 68. So clearly my hypothesis was correct.

  • Nick

    Today in class we conducted an experiment. We conducted two different experiments, with pill bugs, a.k.a rollie pollies, and also know as isopods. The first experiment, we determined whether the isopods, were attracted to either the wet side of a container, or a dry side. We used a total of 10 isopods, 5 on each side at the start. We wanted to know if the bug was attracted to a stimulus, the wet side, or away from the stimulus. My hypothesis, was proven wrong at the end of the experiment. I believed the bugs would be attracted to the wet side. Then, i found out the bugs were strongly opposed to the water.

    In my second experiment i wanted to see if the bugs are attracted or opposed to a dark area. I used the same materials as the wet vs. dry experiment, except instead of pads that were wet or dry, i took them out, and i put a strip of tin foil on top of one side of the container. After 10 minutes of 30 second intervals, i found out that the bugs enjoyed the dark area a lot more than the dry area.

  • Josh

    In the first experiment conducted we were given an experiment involving 10 pill bugs and 2 pieces of filter paper. We wetted one side and kept the other dry. My group had received data showing that 10 out of 21 times the pill bugs went to the wet side and 11 out of 21 times the bugs went to the dry side. That data completely proved our hypothesis wrong. (It was that the bugs would go to the wet side more often.)

    In the second experiment I conducted it involved 10 pill bugs and 2 droplets filled with hydrochloric acid and potassium hydroxide. After a few minutes we noticed that 4 of them were not active. When we took a closer look we noticed that 3 were dead and one was barley moving its antennae. Turns out we put too much acid and hydroxide on the filter paper that absorbed the dangerous liquid. And we also spilled half of the bottle of potassium hydroxide on the desk. Since we were low on test subjects we had to cancel the experiment and forced to move to different groups.

  • Samantha

    In biology class, we experimented with isopods. Our first experiment was to gather information on whether or not the isopods prefer a wet surface over a dry surface. My group, Gabby and Dawood, and I predicted that the isopods would favor the damp side because usually insects hide under rocks or leaves, and those areas are usually moist. Since it is hard for the sun’s rays to reach these spots, they do not dry up very often. We preformed 20 trials, and we were shocked at the results. Instead of staying at the damp side of the maze, most of the isopods crawled around the dry side. I still can’t figure this out. Maybe we did something wrong in our experiment, or maybe the isopods were just too nervous to think straight. Who knows????
    Today, (October 27), we preformed another experiment with isopods. We were able to choose one of the following topics: Temperature, light, Ph, and substrate surface. I choose to do the experiment involving light. I used my hypothesis from the previous experiment, because while I did research on theses insects, I found out that they do indeed like moist places. In order to perform the experiment, we had to cover one side of the maze to block out the light and leave the other side of the maze exposed to the light. We covered the side that needed to be darkened with a piece of aluminum foil. We then placed five isopods on each of the two sides of the maze to begin the experiment, and took note on their behaviors. We recorded how many isopods were on each side of the maze every thirty seconds for ten minutes. That is a total of 20 trials. At the end, our hypothesis was correct! The isopods preferred the darker side of the maze better than the lighter side. This is probably because in their natural habitats, they prefer darker spaces than lighter spaces. In the light, predators could see and eat the isopods. This is a behavior that the isopods use to protect themselves.
    I had a lot of fun performing these experiments and I learned that sometimes, your experiment could contradict data, but there could be a number of reasons as to why.

  • josh

    Our very interesting experiments that were done in class had mixed data especially for the second experiment. Our first one was to see out of ten pill bugs that were put in a petri dish, five on a wet side and five on the dry side. the mode of our data our most occurring number in a set was six bugs on the wet side and four on the dry side however our data was never consistent as we thought our hypothesis could not be proven right or wrong because of the inconsistency in our data.

    The second was so odd and unexpected compared to the first one. It started off as to see if the isopods liked a low pH or a high pH environment. My hypothesis was that the isopods would like a basic environment instead of an acidic one. my hypothesis was proved right but we had to cut the experiment short because we had fatalities in it, three in the hydrochloric acid and one in the the potassium hydroxide. I then had to change me experiment to light and dark where my hypothesis was proven correct in that the isopods would like the dark side more than the light. on average our dark to light ratio was six isopods to four isopods. in this experiment our data was very consistent. that is why we got a conclusive answer to our hypotheses.

  • Eva

    The 9th grade Biology class has conducted two experiments on Rolie-Polies. The first experiment that was conducted was to see whether the isopods would prefer a wet environment or a dry environment. The isopods would walk back and forth, or stay on the same side, while we observed and wrote down the amount of isopods on each side at the end of 30 second intervals. In my personal experiment, the majority of the isopods would choose the wet side. Although there wasn’t vast amounts of isopods on one side, they were consistently choosing the wet side The experiment started out being consistent, but as the experiment progressed, the isopods were showing which side they really preferred.
    The second experiment that I conducted using the isopods was testing to see whether the isopods preferred a rough or smooth surface. Although my Hypothesis stated that the isopods would choose the smoother side of the container, I was proved wrong. The isopods greatly chose the rougher side of the container all through the experiment. There were 11 trials where all the isopods chose the rougher side over the smoother side. The other trials also had vast amounts of isopods choose the rough surface over the smoother side.
    Therefore through both experiments I have come to see that isopods generally prefer rougher, wetter environments.

  • Noa

    For the wet/dry experiment, my hypothesis was that the isopods would prefer the wet side because they live in damp areas (mud and such). However, they were indifferent to whether they were on water or not because they kept going back and forth and I got very mixed results, one time there were many on wet, at one point there were many on the dry. I have concluded from this experiment that they don’t prefer wet or dry, they are fine with either environments.
    The second experiment I did was the smooth vs. rough. After gaining information from the first experiment, my hypothesis was that the isopods would be indifferent to the smooth and the rough sides, and it wouldn’t make a difference to them they would still causally roam around. My conclusion is that isopods prefer the rough side, because according to my data there were more isopods on the rough side than the smooth side every 30 seconds. This is probably because isopods do tend to live in rough areas in dirt and under rocks, so the rough area was a lot like their own habitats.

  • Sabrina

    In 9th grade biology, we tested two different experiments with isopods. Our first experiment was to test whether or not the isopods were attracted to the moist pallet or dry pallet. While keeping a data chart we noticed that the isopods liked the dry side more then the wet. We used 20 trials and the time between each trial was 30 seconds. As an outcome in my experiment was greatly displayed that the isopods really did prefer the dry side better then the wet side of the pallet.
    The next experiment by choice that I chose was to make half the pallet dark by covering it with tinfoil and the other half leaving it as it is, with the light shining in. The point of this experiment was to see which side again of the pallet the isopod preferred. By conducting another 20 trials but this time with only 15 second time lapses between each of the trials, I noticed that the lighter side of the pallet was preferred more, then the dark

  • dawood

    today in class we were doing an expetiment on isopods, and we had a choice of what experiment to do. I chose the ph experiment. In this experiment we were testing to see weather the isopods prefer a place with low ph, or a substance with high ph. When we were about a quater through this experiment, we found out that we put too much liquid on the filter paper and the substances were harming the Isopods. We had 3 fatalities. I still had some data(6 trials out of 20) from this experiment, and i made an inference that the isopods would rather prefer the side with the high ph substance over the low ph substance(hydrochloric acid), and that the low ph substance was harmful to them.

    we each then joined with another group to test another experiment since our first was faulty. I joined naseem and Sam, and we tested weather the isopods pwould og to a light side of a dark side. We had 20 trials for this experiment, and my hypothesis was that the Isopods would go tothe dark side because they usually live in dark damp areas, and i found out that my hypothesis was supported and that the pillbugs went to the dark side. This is prbably an inate behavior buit into these animals to get them out of danger (also noticed in many other insects: regular cockaroaches and hissing cockroaches)

  • Ms Baker

    Dawood, what were your results from the wet/dry experiment?

  • Ms Baker

    I’ve posted a few pictures of our lab on our flickr page. Scroll up to the top of this page and then look for the Pictures icon on the left sidebar!

  • Gabriela

    In our 9th grade General Biology class we have conducted two experiments this week using pill bugs as a part of our lab grade. In our first experiment we tested the reactions the isopods would have to a dry vs. wet surrounding.
    To test this we divided the class into groups of three. Each group was given ten pill bugs, evenly seperated within a plastic container with two chambers, eachchambers floor was lined with paper. One chamber was left dry, the other was saturated with water. Each group observed the reactions of the pill bugs to the wet stimulus. The group I was in collected enough data to say the pill bugs we had been given had a preference to the dry chamber of the container.
    The second experiment done in our General Bio class was seperated by preference of experiment. I chose to do the hot vs. cold temperature experiment. For this experiment the same double chamber containers were used to seperate the hot and cold sides of the cotainer, a heating pad was used to heat one chamber of the container. For this experiment our group was given ten pill bugs once again evenly seperated within the container. Our group tested the reactions of the pill bugs to the heat stimulus. We found that the pill bugs we tested almost always stayed on the side of the container that had the unheated chamber.

  • Naseem

    In class, we’ve been studying and testing isopods’ reactions and preferences with different environmental conditions. In my group’s first experiment, we observed pill bugs react and respond to variations of humidity in their environment. Our hypothesis was that the isopods would prefer the wet side because although they are land-dwelling crustaceans, pill bugs need to remain moist (according to our information packet). The results of this experiment were meant to show a preference of the isopods—whether they favored wetness over dryness, or vice versa. After testing the pill bugs every 30 seconds for 10 minutes by checking how many roly-polies were on each side of our experiment, the outcome was 4.7: 5.4. The results came very close and showed that pill bugs leaned slightly towards dry areas, but by a very small margin. I propose there is no clear preference, because of the nearness of the statistics.
    Today, we were given a choice of what experiment to perform on the pill bugs. I chose the experiment regarding pill bugs’ preference towards light or dark areas. From previous experience, I proposed that the pill bugs would prefer the dark side because I learned that pill bugs hide in shady, humid areas during the daytime, and venture out at night. Sometimes, in my backyard, I’d pick up a rock and find some roly-polies hiding underneath! This, however, did not seem like the case in my experiment. On average, 6.6 pill bugs appeared in the light area after twenty trials, each 30 seconds long. 3.4 pill bugs preferred the darker side, the ratio being 2:1. I propose that in this experiment, pill bugs showed preference in light areas as opposed to dark areas. After finding out both outcomes of both my experiments, I am surprised; my results were unexpected. I hope to read other groups’ similar experiments to find out if they came across the same results!

  • Taylor

    Overall, this working with these pill bugs has become quite interesting. I learned many things about them solely through observation, and didn’t really need to research much. Based on prior knowledge, I found that Isopods live in dirt.
    When my class conducted the first experiment, there were 10 isopods placed into the pallet, with one side wet and one side dry. According to my data/observations the isopods stayed on the dry side most of the time and there was usually more isopods on the dry side, rather than the moist. This is because they have a fear of water, because it could kill them. Their usual environment is warm, rough, and in the dirt. When testing a new habitation for the isopods this strikes a fear, causing them to roll up in a ball form, and stick together with the other isopods.
    In the solo hands on experiment, I had chosen to test out the smooth and rough surfaces. I expected similar results to be presented. Fortunately for me I was correct. I noticed that on the side of the pallet with the rough material, if not all than more than half of the isopods crawled on it. However, I did notice that many of the isopods on the rough side were trying to crawl underneath the rough surface. At first I thought it was to escape, but then I realized that isopods live in the dirt, not above it. Therefore, I inferred that the isopods were searching for dirt layers deeper than the rough surface. Eventually, I took the paint brush and placed them back on top of the rough material, and they stayed there, because they realized if they kept trying to go under the rough material nothing was happening, or changing.
    With both of the experiments I came to terms that isopods live in rough, warm, dirt areas, and DO NOT easily adapt to areas of moisture and wetness (kinesis-> response to a stimulus, but not easily adapted to).

  • James

    In the first part of the experiment we had studied wether the roly polies had liked the wet or the dry side of the paper. I had hypothesized that the isopods will rather a dry side. My groups data had shown that the isopods had preferred the dry side of the paper. Our data had clearly show that the dry side was favored my the isopods. Our hypothesis was clearly correct. The isopods are very interesting creatures and I hope we do more labs on them.

    In the second experiment of the isopods me and Gabby wanted to see if the isopods would rather a warm climate or a cool climate.My hypothesis was that the isopods will rather a warm climate. I though this way because they live under rocks, and this means that they are in a constricted area. THis means that there area of living is warm. At first we started off the experiment by heating up one side and have the other side with a cooling pad. We then put 5 isopods on each side. Then we observed the isopods. After about 1 isopod died. It was clear that the isopods liked the cool climate better. On the cool side most of the time it was 8:1 ratio. Sometimes it was even 9:0 ratio. My hypothesis was wrong. The isopods liked the cool side better.

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