Roly Poly Lab
In this lab, you will be working with terrestrial isopods commonly known as pillbugs, sowbugs or rolypolies. These organisms are members of the Phylum Arthropoda, class crustacea, which also includes
shrimp and crabs. Most members of this group respire through gills.
Objective: To demonstrate how to setup and conduct an experiment using roly-poly behavior as a tool.
Setup: Obtain a white observation chamber and two pieces of filter paper.
Place a piece of filter paper in each side of the chamber.
Obtain an even number of roly-polies up to 20 in a container provided.
Experimental setup: We are considering the behavior of roly-polies. To examine this choose one
independent variable to be considered. The dependent variable for the experiment will be the number of
organisms on each side of the observation chamber over time. Each group will choose a different
independent variable to examine.
Procedure:
1. Place your pillbugs in one side of the observation chamber.
2. They generally don’t climb, but if one escapes carefully place the pillbug at the point of escape.
3. Observe the pillbugs for 5 minutes. RECORD the observations, not inferences, in your notebook.
Notice if they seem to be in any area more often than others, if they keep moving, settle down, or
move sporadically. Note any behavior between two different pillbugs. Don’t disturb the pillbugs
in anyway during the obseravation period.
4. Make a detailed sketch of the pillbug.
5. Return all pillbugs to your container.
6. Construct your chambers to fulfill your independent variable.
7. Consider any controllable variables that you need to equalize.
8. Randomly place pillbugs in the center of each side of the observation chamber in equal numbers.
9. At intervals of 30 seconds record the number of pillbugs on each side of the chamber.
10. After 10 minutes return the pillbugs to the main supply container in good health.
Questions: ANSWER THESE ON YOUR OWN PAPER. WRITE NEATLY WITH COMPLETE
SENTENCES.
1. Why are controlled variables so important to equalize?
2. For this experiment, what is the
a. Independent variable
b. Dependent variable
c. Controlled variable
d. Hypothesis
e. Replication
f. Control
3. Considering YOUR findings, how is this behavior an adaptation for the isopod environment?
4. What would happen if scientific/logical thought didn’t require all the parts of science that we
have discussed over the past few days?