Science Buddies: "Ask an Expert"

For my advanced biology class, I plan on testing mealworms or waxworks but I'm leaning toward mealworms on the effect on the decomposition of plastic. Since plastic has such a long decomposition rate, I want to see how fast mealworms can decompose it. I also want to test how much CO2 is converted. I plan on using this machine my teacher is ordering and I can connect to a glass jar to get the measurements. I plan to use a glass jar with 40 worms and 1 6 g block of polystyrene foam(Styrofoam). Then I would weigh how much the ending mass of the polystyrene foam would be. The problem is that I have to test it against something. I don't know if I should test different types of plastic, different sizes, etc.. If you have any ideas it would be very helpful.

if you use the worms I suggest using both types of worms and then for a control use plastic without any worms

Hi Shelbamesb,

Thanks for asking and using our forum!

This certainly sounds like a cool project! I'd suggest you use both worms and feed them styrofoam pieces. You can then record the rate at which they consume it and compare the two.

You can also set up another trial where you feel them styrofoam and regular diet. You could then compare whether they have preference for either source of food.

Using plastic without any worms isn't really a good control since we know how long it takes for plastic to decompose (forever!). You could use a worm that doesn't consume plastic (earthworm) but then you run into the problem of starving the worm. I'd just use mealworms and wax worms and then compare the consumption rates. As a control to that you can have worms fed only regular diet.

Hope this helps!
Peter S.

So I also plan on testing the CO2 converted. I feel like this could show how much they digesting and putting back into the environment. I like the idea of using both worms for this test. Do you think I should just use one type of plastic (Polystyrene Foam, Styrofoam)?