Bess Beetle Tractor Pull Lab Biology What are they? A beetle commonly found in decaying logs from Texas to Florida and as far north as Canada The mandibles allow the beetle to chew through the hardwood that serves as both food and shelter It will rarely bite the hand that holds it. Antennae "drive" the beetle. It is assumed that they use their antennae to sense odors in the environment— decaying wood or other beetles of the same species On a side note… During this lab you will be working with a living organism. You are to show your beetle respect and any beetles harmed or killed during this experiment will result in a failing grade. Bess beetles have pincers and can pinch, however seldom do. When handling your beetle, gently hold it on either side of it's abdomen with your thumb and forefinger. During the lab, talk in quiet voices and try not to make any sudden movements that may startle your beetle. Pre-Lab Complete the pre-lab. Materials Bess beetles Paper towel Scotch Tape Heavy thread or very fine twine/string Scale Pennies Data sheet Smooth surface table top Plastic Petri dish Ruler The Main Event …let’s get ready to rumble!!! Procedure 1. Obtain a Petri dish and record it’s weight in grams on your lab sheet. 2. Obtain a penny and record it’s weight on your lab sheet. 3. Place a Bess beetle upside down on it’s back in the Petri dish and weigh both. Subtract the weight of the Petri dish and record the difference as the weight of the beetle. 4. Place your beetle on it's back on your lab desk and measure it's length from tip to tip to the nearest millimeter. Place this measurement in your data section. 5. Predict how many pennies the beetle will be able to pull on the Petri dish sled and write this hypothesis on your lab sheet. 6. Cut a piece of thread about 20 cm long. 7. Gently tie a loop of thread around your beetle’s body as show below. 8. Tape the other end to the inside rim of the Petri dish. 9. Place your beetle on the paper towel “track” allowing the Petri dish to slide on the smooth lab desk. 10. When the beetle begins to pull or move the sled by walking, slowly add pennies to the sled one at a time, until you find the maximum weight the insect can pull. It may be necessary to reposition the beetle to prevent the sled from touching the cloth or paper. Do not prod or push the beetle. 11. After you have reached the maximum pennies your beetle can pull, remove the harness from the beetle and return him to your teacher for inspection. 12. Count the total number of pennies pulled, weigh them, and place them in the appropriate place and enter the result in on your lab sheet. 10. Take your dish of pennies and weigh them on the digital scale (use a weigh boat and tare the scale first). Record the weight of the pennies in GRAMS. 11. Fill in your data into the class data table on the board. 12. Copy the completed data table into your lab. Beetle Number Beetle Name Beetle Weight (g) Number of grams pulled Length (cm) 1 2 3 4 5 6 7 8 9 10 11 12 Graph Complete Conclusion and Questions Turn in your lab!