Isolating Isopods Permission to Copy - This document may be reproduced for non-commercial educational purposes Copyright 2009 General Electric Company

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1 Isolating Isopods Permission to Copy - This document may be reproduced for non-commercial educational purposes Copyright 2009 General Electric Company

2 What are Isopods? Definition Isopods are small crustaceans with seven pairs of legs, ranging in size from 300 micrometers to nearly 50 centimeters. Example Isopods go by many names. The round ones that roll up are pill bugs. Those with flat bodies that don't roll are sow bugs. Both may be called wood lice, roly-polies, or potato bugs. Isopods are not bugs or lice -- they are crustaceans related to crabs, lobsters, and crayfish. Why is Isolating Isopods important? This experiment introduces isopods and allows students to realize what environment isopods prefer and how this makes sense, tying into the real world. Goal of experiment To show what kind of environment isopods prefer with respect to lightness, temperature, and moisture. Items needed for the experiment Jar for collection Garden gloves Foil Lamp Black paper Small desk lamp Sand Two teacups Water Optional: Pre-bought isopods. (in this case, skip step 1) Instructions for the demonstration Step 1: Take a jar and collect a dozen or so isopods. Wearing gloves, look under flowerpots, beneath big rocks, under logs or boards, and in compost heaps. Put some damp soil or rotted wood in the jar for the insects to hide in. Step 2: Make an isopod runway. Cut a large piece of foil and fold it in half for strength. Fold it into box shape measuring about eight inches long, two inches wide, and two inches deeps. Step 3: Now experiment to see what kind of environment isopods prefer. Test one factor at a time to decide what factors are most important to the insects. When you are done with the experiments, return the isopods where you found them.

3 Test #1: Light vs. dark. Cover one-third of the length of the runway with black paper. Shine a small desk lamp on the other end. Place the isopods in the middle and see which end they settle down into. Test #2: Dry vs. wet. Put dry sand in one end of the runway. Put wet sand in the other end. Place isopods. Test #3: Cold vs. warm. Fill one teacup with hot water and the other with cold. Set the runway on the two teacups, one at each end. Place isopods. Conclusions The isopods should prefer dark, wet, warm places as they live in the soil. Applications This shows that there is a correlation to what insects like and where their natural habitat is.

4 Name Isolating Isopods Activity Sheet ISOLATING ISOPODS One very interesting insect experiment you can do is to be an isopod expert. Whether you call them pill bugs, sow bugs, or potato bugs, isopods are fun to observe. Guess which habitat the isopods prefer. Circle your guess. Put isopods under the different conditions. Circle which condition they like best. CONDITION GUESS EXPERIMENT RESULTS Lightness Moisture Temperature EXPERIMENT RESULTS light dark wet dry warm cool What habitat do the isopods like best? CONCLUSION Was your guess correct? light dark wet dry warm Knowing the habitat of the isopods, where do you think you d be most likely to find them? REFLECTION cool Did you know isopods have gills? This means they are restricted to areas with high humidity. Does this make sense with what we learned in the experiment? If you were to catch isopods, what would you do and how would you maintain the area?

5 ISOLATING ISOPODS This activity explores live science and scientific method. This could serve as an introduction to scientific inquiry followed by students coming up with their own questions based on their findings. NYS Standard 4: The Living Environment Key Idea 5: Organisms maintain a dynamic equilibrium that sustains life. P.I. 5.1 Describe basic life functions of common living specimens. 5.1b P.I. 5.2 Describe some survival behaviors of common living specimens. 5.2a 5.2c 5.2f 5.2g NYS Standard 1: Analysis, Inquiry, and Design Scientific Inquiry Key Idea 1: The central purpose of scientific inquiry is to develop explanations of natural phenomena in a continuing, creative process. S1.1 S1.2 S1.3 Key Idea 2: Beyond the use of reasoning and consensus, scientific inquiry involves the testing of proposed explanations involving the use of conventional techniques and procedures and usually requiring considerable ingenuity. S2.1 S2.2 S2.3 Key Idea 3: The observations made while testing proposed explanations, when analyzed using conventional and invented methods, provide new insights into phenomena. S3.1 S3.2 S3.3 S3.4