PILL BUG RESPONSES
Introduction
Pill bugs, shown in Figure 1, are isopods. Although they resemble
insects, isopods are crustaceans, cousins of crabs, lobsters, and shrimp.
Most isopods are aquatic, which means that they live in a watery
environment. However, a few species, including pill bugs, are terrestrial—
that is, land-dwelling—animals. The exoskeletons of these organisms
differ from those of other crustaceans because they lack waxy coverings,
called cuticles. The absence of cuticles plays an important role in
isopods’ behavior. These animals require moist environments, and they
depend on instinctive behaviors to help them locate suitable
surroundings. In this experiment, you will find out how pill bugs make
choices about where they live.
pill bug
Figure 1
Figure 1
Time Needed
55 minutes
What You Need
F container (small aquarium or shoe box)
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PILL BUG RESPONSES
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F 2 pill bugs
F soil (about 1 cup [c])
F sand (about 1 c)
F leaf litter or strips of shredded paper (about 1 c)
F small rock
F gooseneck lamp or heating pad
F small aquarium or shoe box
F clock or timer
F access to water
F science notebook
Safety Precautions
Handle isopods with care, touching them as little as possible.
After working with isopods, wash your hands with soap and
water. Please review and follow the safety guidelines.
What You Do
1. Your job is to design an experiment to investigate the responses of
pill bugs to two different environmental stimuli (such as moist or dry
conditions, high or low temperatures, dark or well-lit habitats).
2. Before you conduct your experiment, decide exactly what you are
going to do. In your science notebook, write the steps you plan to
take. The steps should be clear and simple so that anyone could
follow them. Be sure to keep all experimental factors that are not
being manipulated the same. For example, if you design an
experiment to find out if pill bugs prefer a dark or well-lit
environment, be sure to keep factors such as temperature and
moisture constant.
3. In your science notebook, make a list of the materials you will need
to conduct your experiment. You can use any of the supplies
provided by your teacher, but you will not need to use all of them.
4. Show the teacher your proposed experiment and materials list. If you
get teacher approval, proceed with your experiment. If not, modify
your work and show it to your teacher again.
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PILL BUG RESPONSES
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5. In your notebook, record all of the data you collect.
6. At the end of your experiment, analyze your results and draw a
conclusion.
7. Exchange the results of your experiment with your classmates.
Observations
1. The hypothesis of an experiment states what you expect
to happen. What was the hypothesis of your experiment?
2. In an experiment, the manipulated, or independent
variable, is the factor in the experiment that you change.
In this experiment, what was the manipulated variable?
3. State the conclusion of your experiment.
4. You have been asked to go outdoors and collect some
pill bugs for your science class. In which location do you
think you would be most likely to find some pill bugs: in
the soil under a rooting log or in a grassy field. Explain
your reasoning.
Want to Know More?
See Our Findings.
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SAFETY PRECAUTIONS
Review Before Starting Any Experiment
GENERAL
• Always obtain your teacher’s permission for experiments performed
at school, and your parent’s permission for experiments performed
at home, before attempting any experiment.
• Read all instructions for an experiment before starting the
experiment, and follow the directions exactly as they appear in
this volume.
• If an experiment requires adult supervision, do not perform the
experiment unless you have an adult supervising you the entire
time you are performing the experiment.
• Wash your hands before the start of and after each experiment
you perform.
• Keep your work area clean.
• Never eat or drink while performing an experiment. Never taste a
substance used in an experiment unless you are told that it is safe
to do so.
• Be aware of the location of safety equipment you may need in an
emergency, such as running water, an eyewash if you are at school,
and a fire extinguisher.
• If you are going outside, make sure you have permission to go
from your teacher and parent. Take a buddy with you, and dress
appropriately for the weather. Make sure you or someone who
accompanies you is familiar with the area, and bring along a firstaid kit in case of emergency.
• Never look directly into the Sun.
CHEMICAL SAFETY
• Always wear goggles when working with chemicals, such as acids
and bases, and near heat sources like flames. If at all possible,
avoid wearing contact lenses when working with chemicals.
• If any substance gets into your eyes, notify an adult (e.g., your
teacher or parent) immediately, and flush your eyes with running
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SAFETY PRECAUTIONS
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water for at least 15 minutes. Do not mix chemicals unless you are
told to do so by a teacher or parent.
• Never touch, taste, or smell chemicals unless instructed to do so.
• Keep chemicals in closed containers when they are not in use.
• Dispose of all chemicals properly. Do not pour any chemicals or
solids down the drain unless instructed to do so.
• Use safety gloves and a plastic apron when handling chemicals. If
any chemicals spill on your skin, rinse the affected area with
running water for at least 10 minutes, and notify your teacher or
parent immediately.
• Take precautions to avoid spilling chemicals. If a chemical spills on
any surface, notify your teacher or parent immediately to assist
with clean-up.
• Exercise caution when using sharp instruments such as knives or
scissors. Always cut away from yourself, not toward yourself. If you
cut yourself, notify your teacher or parent immediately.
GLASSWARE
• Clean glassware when you are finished with the experiment.
• Be careful when using glassware. If a piece of glassware breaks,
have an adult assist you in clean-up to avoid injuries from broken
glass. Never use broken or damaged glassware.
FIRE SAFETY
• Do not heat glassware that is not completely dry. Do not pick up
hot glassware without heat-resistant gloves or tongs.
• When heating glassware, keep it away from yourself and from
others.
• Do not heat anything unless instructed to do so by a teacher or
parent.
• Do not heat substances in a closed container.
• After an experiment, make sure that all heating sources are off
and that all flames have been put out.
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SAFETY PRECAUTIONS
• Do not reach across such heating sources as flames.
• If you have long hair, tie it back, out of the way. Do not wear
clothing with loose sleeves, scarves, bows, ties, or anything else
that may hang into a fire. Do not wear long earrings.
ELECTRICAL SAFETY
• Do not touch electrical equipment when your hands are wet.
• Do not plug several electrical devices into one outlet or use an
extension cord.
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