Background:
Industrial melanism is the term used to describe the adaptation of darkening by an organism in response to industrial pollution. One example of rapid industrial melanism occured in the peppered moth, Biston betularia , in the area of Manchester,
England, from 1845 to 1890.
Before the Industrial Revolution, the trees in the forest around Manchester were light grayish-green due to the presence of lichens on their trunks. Peppered moths, which lived in the area, were mostly light-colored with dark spots. Very few moths were dark colored with light spots. Their coloring served as a camouflage against predators, especially birds. As the Industrial Revolution progressed, the trees became covered with soot and the lichens died, which turned the tree trunks dark. Over a period of 45 years, a change took place in the peppered moth population in this area: light-colored moth numbers decreased and dark-colored moth numbers increased.
In this investigation, you will simulate a predator-prey situation and determine if color contrast has an effect on the ability of a predator to rapidly locate prey. In the second part of the investigation, you will study the data on peppered moth coloration as actually reported over the course of several years. You will then determine the relationship between the environmental changes and the color variations of the peppered moths by using the research data to graph the results of an environmental adaptation.
Problem: What is the relationship between environmental changes and the color variation of the peppered moth?
Materials: sheet of newspaper sheet of white paper graph paper
30 newspaper disks
30 white paper disks forceps
Procedure:
Part A- Simulating Predator-Prey Relationships
1) You will use the disks of white paper and newspaper to simulate prey (peppered moths). You will use forceps to simulate a bird’s beak and capture as many of your prey as possible in a 15 second time period.
2) Place the white paper on your lab table. While your teammate is looking away, scatter 30 white disks and 30 newspaper disks on the paper. When your partner is ready, let them hunt with their forceps and you start timing.

3) When 15 seconds have elapsed, count how many of each type of disk were picked up. Record the number of captured disks of each type and the number of disks remaining for each type.
4) Replace the white paper with a sheet of newspaper. While your partner is looking away, scatter 30 newspaper disks and 30 white disks. Repeat the hunting procedure. Record the number of each type of disk picked up and the number of each type that remains.
Name of Predator 1: _____________________________________
5) Change roles. You play the predator, while your partner sets up the disks.
Name of Predator 2 : _____________________________________
Did you and your partner each pick up the same amount of “prey”? ___________
6) After you have recorded data for one trial using a white background, and one trial using a newspaper background for each lab partner, compute the Percentage of
Available Prey Recovered for the contrasting and matching background situations.
To do this, divide the total number of disks recovered that contrasted with their background by the total number of disks of that type. Repeat this procedure with the total number of disks recovered that matched their background.
Example: If you scatter 30 newspaper disks and 30 white disks on a sheet of newspaper, and you recover 5 newspaper (matching) disks and 15 white paper (contrasting) disks, your recovery rate is:
5 x 100% = 17% for the matching background
30
Likewise your recovery rate is:
15 x 100% = 50% for the contrasting (opposite) background
30

Percentage of Available Prey Recovered
Did the background play an important role in your selection of “prey”? Explain.
____________________________________________________________________
____________________________________________________________________
Part B- Graphing and Analyzing Predator-Prey Relationships
7) Table A represents data from a 9 year study of two varieties of the same species of peppered moths. The numbers represent moths captured in traps for 9 consecutive years. The traps were located in the same are each year.
Table A.
Year
1
2
Light moths captured
537
484
Dark moths captured
112
198
7
8
9
3
4
5
6
392
246
225
193
147
84
56
210
281
357
412
503
594
638
8) Using the data provided in Table A, construct a line graph, on graph paper, comparing the numbers of each variety of peppered moth. Label the axes with the years of the study (x-axis) and the number of moths captured (y-axis). Use different colored pencils to indicate the two color variations . Be sure to include a key and title your graph.

Questions: Use your graph and this lab to answer the following questions.
1) What preys on the peppered moth?
2) If the bark of the trees is dark and the moths that rests there are light, what will happen to the light-colored moths?
3) What could have caused the first dark-colored moth?
4) What caused the tree trunks of many trees in Manchester to turn from a light color to a dark color?
5) Using your graph, what variety of moth population increased over the 9 year period? Which moth variety decreased?
6) What is the name of this type of evolutionary change?
7) What could be done to return the environment of the peppered moth to its original state?
8) What effect would cleaning up the environment have on the moths?