Peppered Moth Survey
Introduction: Before the Industrial Revolution, the trees in the forest in
Manchester, England were light grayish-green. Peppered moths, which lived in
the area, were colored light with dark spots. Their coloring served as a protective
camouflage against predators. As the Industrial Revolution progressed, the trees
became covered in soot, turning the trunks dark. As a result, a change in the
peppered moths took place. Industrial melanism is a terms used to describe the
adaptation of an organism in response to a type of industrial pollution.
Data:
Year
1
2
3
4
5
6
7
8
9
10
Number of light moths
585
537
484
392
246
225
193
147
84
56
Number of dark moths
86
112
198
210
281
357
412
503
594
638
Procedure:
1. Make a graph of the above data. Plot the years along the X-axis, and the
number of moths along the Y-axis. Be sure to include a title, labels for the
axes, and labels/a key for each population of moths.
2. Answer the questions that follow.
Questions:
1. What happened to the population of light-colored moths over the years?
2. What happened to the population of dark colored moths over the years?
3. Why did the populations change over time as they did? In other words,
what caused one population to increase while the other decreased?
4. What variations existed in the moth populations?
5. Explain why those variations eventually became adaptations. (Variations
may or may not affect fitness, adaptations DO affect fitness.)
6. What effect(s) would cleaning up the environment have on the
populations of moths?