Download Peppered Moth Simulation Lab I. Purpose: In this lab, you will

Peppered Moth Simulation Lab
I. Purpose:
In this lab, you will simulate how predators locate prey in different
environments. You will analyze how color affects an organism's ability to survive in certain
environments.
II. Background:
Describe the importance of coloration in avoiding predation. Relate
environmental change to changes in organisms. Explain how natural selection causes
populations to change.
Industrial Melanism is a term used to describe the adaptation of a population in response to
pollution. One example of rapid industrial melanism occurred in populations of peppered moths
in the area of Manchester, England from 1845 to 1890. Before the industrial revolution, the
trunks of the trees in the forest around Manchester were light grayish-green due to the
presence of lichens. Most of the peppered moths in the area were light colored with dark spots.
As the industrial revolution progressed, the tree trunks became covered with soot and turned
dark. Over a period of 45 years, the dark variety of the peppered moth became more common.
This website is the simulation.
http://www.biologycorner.com/worksheets/pepperedmoth.html
Peppered Moths
Peppered Moth Simulation
Objective: Simulate changes in moth population due to pollution and predation, and observe
how species can change over time.
Introduction:
Charles Darwin accumulated a tremendous collection of facts to support the theory of evolution
by natural selection. One of his difficulties in demonstrating the theory, however, was the lack
of an example of evolution over a short period of time, which could be observed as it was taking
place in nature. Although Darwin was unaware of it, remarkable examples of evolution, which
might have helped to persuade people of his theory, were in the countryside of his native
England. One such example is the evolution of the peppered moth Biston betularia.
The economic changes known as the industrial revolution began in the middle of the
eighteenth century. Since then, tons of soot have been deposited on the country side around
industrial areas. The soot discoloured and generally darkened the surfaces of trees and rocks. In
1848, a dark-coloured moth was first recorded. Today, in some areas, 90% or more of thepeppered moths are dark in colour. More than 70 species of moth in England have undergone a
change from light to dark. Similar observations have been made in other industrial nations,
including the United States.
Instructions:
You will run two simulations for 5 minutes each, during this time you will play the part of a
bluejay that eats moths. After 5 minutes record (on scratch paper) the % of dark moths and
light moths - you will need this information later.
Run Lichen (light colored) forest
Run Soot (dark colored) forest
Analysis - answer all questions below and submit to your teacher.
Go to this website to run the simulation.
http://www.biologycorner.com/worksheets/pepperedmoth.html
VI. Data Collection:
Starting Population
Trial
Background
1
White- Lichen
2
Sooty- Dark
Dark
White
Number Picked up
White
Dark
VII. Data Analysis:
1. What did the experiment show about how prey are selected by predators?
2. What moth coloration is the best adaptation for a dark (newspaper) background? How do
you know?
3. Calculate how many white and peppered moths remain after trial 1. What would you expect
the next generation of moths to look like after trial 1? What about the next generation after
trial 2?
4. How does this simulation model natural selection?
5. Examine the table and construct a graph. Plot the years of the study on the X-axis, and the
number of moths captured on the Y axis. You should have 2 lines on your graph - one for light
moths, and one for dark moths.
# of
# of
Light
Dark
Year
Moths
Moths
Captured Captured
2
537
112
3
484
198
4
392
210
5
246
281
6
225
337
7
193
412
8
147
503
9
84
550
10
56
599
6. Explain in your own
words what the graph
shows.
7. Describe a situation
where this type of selection
might occur.
VIII. Evaluation: Did your data support your hypothesis? Why or why not? What does the
graphed information above reveal about inherited characteristics in a population changing over
time?