Peppered Moth Stimulation
Data and Analysis
Read the background information and answer the questions as you go.
Life Cycle of the Peppered Moth
1. Why are these moths called "peppered moths?"
Their light wings are 'peppered' with dark spots.
2. What animals eat the peppered moth?
Flycatchers, European robin, and nuthatches.
3. What is a lichen?
Small fungi.
4. What do the larvae of the moth eat?
Leaves of birch, oak, and willow trees.
5. How do peppered moths spend the winter?
They change into pupae.
6. Moths that have more dark spots than the average moth are called what?
Insularia.
Impact of Pollution
7. Where was the virst black form of the moth found?
Near the centre of Manchester.
8. What was the Industrial Revolution?
Factories were beginning to be built and started burning coal for fuel.
9. What was causing the different colors in the moths?
It was caused by a mutation in the DNA of a single moth and was passed down to its offspring; the dark spots are genetic.
10. What is natural selection?
The explanation of why new species evolve. If an individual in the species has a slightly different characteristic that helps it live longer, it will produce offspring that looks/does the same thing as the individual did. Therefore, as more offspring are produced, that species begins to look more and more like that successful individual.
11. Who suggested that peppered moths were an example of natural selection?
J. W. Tutt
12. What is industrial melanism?
Species changing as a result of pollution. Ex: When the moths got darker spots because of the pollution in the dark forests.
Kettlewell's Experiments
13. What is an entomologist?
A scientists who studies insects.
14. How do scientists test theories?
By making predictions based on the theory.
15. Write down ONE of Kettlewell's predictions.
Heavily polluted forests will have mostly dark peppered moths.
16. Dark moths were found in what parts of the country?
Industrial cities producing pollution.
17. How did Kettlewell directly study the moths?
He placed dark and light moths on trees where he could observe them.
18. Why did dark moths have a survival advantage?
In a DARK forest, birds are less likely to see a DARK moth on the tree trunks.
19. When Kettlewell recaptured the marked moths, what did he find?
Twice as many light moths were recaptured in a clean forest, while only half were recovered in a polluted forest.
20. Where did Kettlewell publish his findings?
In 1959 when he published an article named, "Scientific American."
Birdseye View
21. Open the simulation and play the role of the bird in both the dark and the light forest. Try to behave as a bird would behave, choosing the moths that are the most obvious. At the end of each simulation, record the percent of moths captured in the table below.
Light Forest: 85% Light Moths & 15% Dark Moths left.
Dark Forest: 41% Light Moths & 51% Dark Moths left.
Final Analysis
22. Explain how the color of the moths increases or decreases their chances of survival.
When you're living in a clean, bright, and light area or atmosphere, the same color wings camouflage in that habitat. On the other hand, if a moth is living in a dark, polluted forest, then it's dark colored wings will help the moth blend in to its surroundings easier. In both cases, the color of the wings will help it survive unless it's in the "wrong" forest.
23. Explain the concept of "natural selection" using your moths as an example.
The moths gradually over the years got darker since they lived in more polluted areas to help them survive. For example, in the dark forest simulation, the light colored moths were easily seen since they didn't blend in to that environment, but the dark colored moths weren't eaten or seen as easily because they were able to blend in since they had a darker colored wings.
24. What would happen if there were no predators in the forest? Would the colors of the moths change over time? Defend your answer?
Yes, the predators weren't the biggest factors for the color change, it was also the pollution around the area. Aside from that, the trees and other elements around the forest also affected the color change. In an unpolluted area, tree trunks are lighter, therefore also are the moths.