Mealworm Behavior

1. Open the Virtual Lab: Mealworm Behavior

2. The lab simulation will be on the right side of the screen, the “Question” column will be on the left side of the screen.

3. Click the play button on the video controller in the lab simulation to watch an introductory video about mealworms.

4. Read the background information and instructions in the “Question” column.

5. Yellow mealworms are the larva stage of what animal? (highlight your answer)
a. Monarch Butterflies
b. Darkling Beetles
c. Water Beetles
d. Dung Beetles

6. What is the definition of a “stimulus?”

A stimulus is an environmental change that directly influences the activity of a living organism or one of its parts.

7. Click a file tab to select a stimulus to examine. Read the stimulus question on the file card. Predict how the mealworm will respond to the stimulus. Note: Your predictions will not be evaluated—this is called making a HYPOTHESIS (an educated guess). Proving or disproving hypotheses is how important scientific discoveries are made. For this assignment, IT IS MORE IMPORTANT TO BE HONEST THAN CORRECT FOR YOUR PREDICTED BEHAVIOR.

8. Drag one of the three responses to the Predicted Behavior area, and record
your prediction in the table on the next page.

9. Click the play button on the video controller.

10. Watch the video to see how the mealworm reacts to the stimulus.

11. Drag the response that corresponds to the mealworm’s actual behavior to the Actual Behavior area. Record the Actual Behavior in the table on the next page.

12. When you have finished the first set of four stimuli, click the “Reset” button in the top right of the screen to obtain four NEW stimuli. Repeat until you have completed at least 8 of the 14 available stimuli. NOTE: You may need to “reset” multiple times to access all the stimuli. DO NOT test the bran flakes stimulus – this will be used later.

Table 1: Record your predicted behavior and the actual behavior for each stimulus applied to the mealworm.

Stimulus
Predicted Behavior
Actual Behavior
Petri dish with light and dark colored sides
Mealworm will stay on light side

Mealworm goes to dark side
Piece of cooked macaroni
Mealworm eats macaroni

Mealworm moves towards macaroni and begins eating
Touched by a Feather
The mealworm will wiggle around

The mealworm began to wiggle
Beam of light shines on mealworm’s head
Mealworm moves away from light

The mealworm moved away from the beam of light
Drops of ammonia placed near mealworm
Mealworm will back away from ammonia

The mealworm backed away from ammonia
A piece of uncooked macaroni
Mealworm goes away from uncooked macaroni

Mealworm went away from uncooked macaroni
Touched by a metal paper clip
Mealworm will stay still
Mealworm becomes still
Drops of apple juice placed near mealworm
Mealworm will move towards apple juice and then drink it
The mealworm moved towards the apple juice and began drinking. Air blown on mealworm’s head
Mealworm becomes still
The mealworm moves away from air blown on its head
Slice of apple introduced
The mealworm moves towards the apple slice and begins eating. Moved towards apple and began to eat
Alarm beeps near the mealworm
Mealworm will stay still
Mealworm became still
Cool water dropped on the mealworm
The mealworm will curl up
The mealworm jumps and becomes still
A piece of banana is introduced
The mealworm moves towards the banana and eats it
Moved towards banana and began eating

13. Review your recorded stimuli responses. Do you notice any patterns?

Patterns that are common to a mealworm are that mealworms will move towards and fruit that are juicy or have a sweet taste to it. When touched by a physical stimulus the meal worm either become still, or begins to wiggle around. Mealworms prefer darkness over light.

14. Select a new stimulus you would like to test (one not mentioned above). a. Give a new hypothesis for how you think the mealworms would react. Explain your reasoning (Example: “I think that if I do ___________ the mealworm would then ________________ because _______________.”)

I believe that if a piece of lettuce was placed in front of the mealworm it would then move towards the piece of lettuce and begin to eat it due to lettuce being composed mostly out of water.

b. How would you test your hypothesis?

I would place a mealworm and a piece of lettuce into a Petri dish, and then record the reaction of the mealworm when presented to the stimulus.

15. Read the following hypothesis, and then answer the questions:

After observing that mealworms move toward cooked macaroni, but away from uncooked macaroni, you form the following hypothesis:

“Mealworms only move toward food that is moist”

You decide to test your hypothesis with dry bran flakes. You use a mealworm exposed to cooked macaroni as your control group, and a mealworm exposed to bran flakes as your experimental group.

a. Write out your prediction (a prediction is an “if…..then….” statement based on your hypothesis (see above)) Since bran flakes are dry if they were to be presented to a mealworm then the mealworm would turn away from them since there is no moisture present.

b. Return to the lab simulation, and reset the stimuli until “Bran Flakes are introduced” comes up as a stimulus. Make your prediction and watch the video associated with the bran flakes stimulus.

c. Was your hypothesis supported?

No, as soon as the bran flakes were presented the mealworm moved straight towards them and began to burrow inside of them.

d. Write one question that this raises in your mind. Write a new hypothesis based on this question and describe a new experiment you could use to answer this question.

If mealworms are attracted to moisture, and tend to move away from hardened food, why would the mealworm move towards bran flakes and begin to go inside the pile.

If a meal worm is presented to different types of dry cereal, then the meal worm will move towards it and begin to burrow.

As an experiment I would place multiple kinds of cereal in front of a single mealworm, and record their reactions to each certain type of cereal.