Beetle Lab
The passalide, also known as the Bess beetle, are reported to be able to carry 30 times their weight. A scientist names Rodger Kram studies these beetles. But really how strong is the Bess beetle? Does beetle mass seem to affect a beetles pulling power? A way to observe this is by conducting an experiment to see how many pennies beetles of diverse masses can pull. If the beetle mass is related to the beetles pulling power, then a beetle with more mass will have a higher pulling power. Materials
Electronic balance
Bess Beetle
Petri dish
String
Pennies
Table
Paper
Methods
1. Draw and label the beetle
2. Find and record the mass of the petri dish by using an electronic balance
3. Find and record the mass of a penny
4. Place the beetle in the petri dish
5. Find the mass of the petri dish and the beetle combined
6. Tape a long piece of paper to the table. The beetle’s legs need friction on order to pull the pennies
7. Make a loop with the string and place between the thorax and abdomen of the beetle. Make sure to follow the teacher’s direction exactly.
8. Tape the opposite end of the string to the petri dish
9. Make an area of darkness because beetles prefer to be in the dark. They should pull the pennies in that direction because they like the dark
10. As the beetle is moving, add a penny one-by-one. Do this until the beetle can no longer pull
11. Find the total mass of the pennies the beetle could pull using the electronic balance.
12. Take the string off the beetle carefully. Return the beetle to its habitat
Independent variable- Group number or mass of the beetle
Dependent variable- How much mass it could pull
Controlled Variable- Health of bug, size of petri dish, how far to the darkness
Control Group- No control group
Group Number
Mass of beetle in grams
Number of pennies pulled
Actual mass pulled
Pulling power
1
1.73
10
42.79
24.73
2
1.63
7
25.42
15.6
3
2.22
9
29.28
13.19
4
1.51
6
22.7
Electronic balance
Bess Beetle
Petri dish
String
Pennies
Table
Paper
Methods
1. Draw and label the beetle
2. Find and record the mass of the petri dish by using an electronic balance
3. Find and record the mass of a penny
4. Place the beetle in the petri dish
5. Find the mass of the petri dish and the beetle combined
6. Tape a long piece of paper to the table. The beetle’s legs need friction on order to pull the pennies
7. Make a loop with the string and place between the thorax and abdomen of the beetle. Make sure to follow the teacher’s direction exactly.
8. Tape the opposite end of the string to the petri dish
9. Make an area of darkness because beetles prefer to be in the dark. They should pull the pennies in that direction because they like the dark
10. As the beetle is moving, add a penny one-by-one. Do this until the beetle can no longer pull
11. Find the total mass of the pennies the beetle could pull using the electronic balance.
12. Take the string off the beetle carefully. Return the beetle to its habitat
Independent variable- Group number or mass of the beetle
Dependent variable- How much mass it could pull
Controlled Variable- Health of bug, size of petri dish, how far to the darkness
Control Group- No control group
Group Number
Mass of beetle in grams
Number of pennies pulled
Actual mass pulled
Pulling power
1
1.73
10
42.79
24.73
2
1.63
7
25.42
15.6
3
2.22
9
29.28
13.19
4
1.51
6
22.7