All lessons › Dung beetles to the rescue › Lesson 2
Australian primary science · Year 4 · Lesson 2 of 3
Did the beetles work?
Inquiry question: What does the data show about dung beetles, dung pads and flies?
Marked no materials needed
Pattern seeking
What students learn
Scientists collect data to find out whether an idea works. Data from paddocks with and without dung beetles shows that decomposers break dung down much faster and reduce the flies that breed in it.
Success criteria
- I can read and compare two columns of data.
- I can describe the difference the beetles made.
- I can explain why the scientists compared paddocks with and without beetles.
Preparation and materials
Before this lesson: Students know why cow dung piled up and why dung beetles were brought to Australia (lesson 1).
- One screen or projector to show this lesson’s student view (the dung beetle trial data) (or print one student view per pair) — 1
- Workbooks or scrap paper, and pencils — 26
Teacher setup
- Open this lesson’s student view (the dung beetle trial data) on your screen, or print the student view if the internet is unreliable.
- No other preparation is needed.
Safety and adaptations
Follow school science and equipment risk assessment procedures for the materials used.
Review your school policies and curriculum requirements before teaching.
How to investigate
The lesson sequence should leave pupils with evidence to interpret, not only an activity to finish.
- Pairs read the trial data table in the student view.
- For each week, compare the pad left with and without beetles.
- Compare the flies hatching from each kind of pad.
- Write a conclusion sentence: what difference did the beetles make?
- Discuss: what did the scientists keep the same? Is one paddock enough to be sure?
Teacher modelling prompt
Point to week 1. Think aloud: “With beetles: 40% of the pad left. Without beetles: 95% left. That’s a big difference after just one week. I’ll check the other weeks to see if the pattern stays the same.”
Record and explain evidence
Recording question: What does the data show about dung beetles, dung pads and flies?
| Week | Pad left: with beetles (%) | Pad left: no beetles (%) | Difference | What this shows |
|---|---|---|---|---|
| ________________ | ________________ | ________________ | ________________ | ________________ |
Example recording headings; record actual observations, including inconclusive results.
Discussion prompt
What did the scientists do that helps us decide?
Provided example or reference data
Example data: cow dung pads in one paddock in summer, with dung beetles able to reach them or kept out by a fine mesh cage (made up for this lesson, similar in pattern to real trials)
| Measurement | Beetles could reach the pads | Beetles kept out |
|---|---|---|
| Pad left after 1 week | 40% | 95% |
| Pad left after 2 weeks | 10% | 90% |
| Pad left after 4 weeks | 5% | 80% |
| Pad left after 8 weeks | 0% (all buried) | 60% |
| Bush flies that hatched from each pad | about 20 | about 300 |
Check the data source in the teacher lesson. Illustrative or fictional data are not measurements collected by your class.
Check understanding
What should pupils know? What do dung beetles do to cow pads?
Explain with evidence: After 4 weeks, 5% of the pad was left with beetles and 80% without. What does this show?
Apply the idea: Why did the scientists cover some pads with a mesh cage? Stretch (older students): how could they make their conclusion more trustworthy?
Teacher answer guidance and saved classroom work are available through the main lesson experience where supported.