In this activity, you will design and conduct your own experiment investigating isopod behavior.
Background Information of our Model Organisms
Isopods: Roly-polies (Armadillidium vulgare)
Terrestrial isopods are land-dwelling crustaceans, commonly known as Roly-polies or pill bugs. Related to lobsters, crabs, and shrimp, terrestrial isopods breathe with gills. Roly-polies are humid retreats during the day. Roly-polies can be found in compost piles, leaf litter, and beneath logs. Roly-polies usually feed on decomposing plant matter. Plants decompose with the help of bacteria, which thrive in soil above 4.9 pH. Roly-polies need calcium in their diet to build up their hard protective cuticle, and calcium is not abundant in soils with a pH below 5.5. The ideal soil pH conditions for Roly-polies are above 5.5 where calcium is present but below 9, the maximum threshold for soil bacteria.
Available Materials
10 isopods in a petri dish, choice chamber, stopwatch or timer, list of other materials required:
Conditions
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temperature
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(cool vs. warm)
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light
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(light vs. dark or light vs. shade)
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pH
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(neutral pH vs. low pH vs. high pH)
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substrate (soil)
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(soil vs no soil)
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salinity
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(saltwater vs. freshwater)
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substrate (leaf litter/organic matter)
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(leaf litter vs no leaf litter)
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