Peppered Moth Activity

 

Objective:  To determine what influence the environment has on the survival of an organism with certain characteristics.

 

 

Materials:

Experiment 1                                                                 Experiment 2

1 black environmental tray                                             1 green environmental tray

1 set of moths of different skin intensities                        1 set of squares of different sizes

data chart                                                                     data chart

moth reference chart                                                     square reference chart

 

Procedures – Experiment 1:

1. Obtain 1 black environmental tray, 1 set of moths and 1 data chart per group.  One student places the moths into the tray as spread out and randomly mixed as possible while other students look away.
2. A second student quickly selects 5 moths from the tray, one at a time.  Set these 5 moths aside on the table. 
3. Record which 5 moths were selected by comparing them to the Moth Reference Chart.  Place a tally mark in the group data chart for each moth selected. 
4. Repeat steps 2 and 3 with everyone in the group.  Use one member’s data chart to record all group tallies.  Keep selected moths on the table--do not put them back into the tray until everyone is done.
5. Count the tally marks and record the total group data in the appropriate column of the data chart.
6. Return moths to plastic envelopes.
7. Trade your black tray and moths with a group that has the green tray and squares.

 

Procedures – Experiment 2:  

1. Obtain 1 green environmental tray, 1 set of squares and 1 data chart per group.  One student places the squares into the tray as spread out and randomly mixed as possible while other students look away. 
2. A second student quickly selects 5 squares from the tray, one at a time.  Set these 5 squares aside on the table.
3. Record which 5 squares were selected by comparing them to the Square Reference Chart.  Place a tally mark in the group data chart for each square selected.

4.   Repeat steps 2 and 3 with everyone in the group.  Use one member’s data chart to record all group tallies.  Keep selected squares on the table--do not put them back into the tray until everyone is done.

8. Count the tally marks and record the total group data in the appropriate column of the data chart.

4. Return squares to plastic envelopes.
5. Trade your green tray and squares with a group that has the black tray and moths.

 

After completing both experiments

For the supplies you have last:

1.  Group the moths into similar colors, arranging groups single file from white to black OR group the squares into similar sizes, arranging groups single file from small to large.  Combine all moths from the class into one large group.  Do the same for the squares.

2.  Count how many moths OR squares there are in each group.  Record numbers on the data chart below Total Class Data. 

 

 

How will this be graded? . . . check out the rubric

 

 

DATA TABLES

 

Experiment 1

 

Moth	Group Tally	Total Group Data	Total Class Data
A
B
C
D
E
F
G
H
I

 

 

 

 

Experiment 2

 

Square	Group Tally	Total Group Data	Total Class Data
A
B
C
D
E
F
G
H
I

 

 

ANALYSIS AND DISCUSSION

1. Look at the class data for which colored moths were selected.  Add up all the numbers on either side of group E.  Do not include the number for group E in the count.  Did the class select out more lighter-colored moths or darker-colored moths?

 

 

2. Why do you think this pattern of results was observed?

 

 

 

 

 

3. Look at the class data for which different sized squares were selected.  Add up all the numbers on either side of group E.  Do not include the number for group E in the count.  Did the class select out more smaller-sized squares or larger-sized squares?

 

 

4. Why do you think this pattern of results was observed?

 

 

 

 

 

Suppose the moths selected lived in a forest where most of the trees had light colored bark.  Also, there are birds in the forest that eat moths.

 

5.   Which moths would be more likely to be eaten?  Why?

 

 

 

 

 

 

6.   Would your answer be different if most of the trees in the forest had dark colored bark?  Why or why not?

 

 

 

 

 

 

7.   Based upon the results of this activity, does the environment influence the survival of organisms with certain characteristics?  Use your lab results to support your statement.

 

 

 

 

 

 

 

 

8.   What advantage do organisms that survive have?