Peppered Moth Story

1
Peppered Moth Story

• Practical

2
Introduction

• In unpolluted areas bark is covered with lichen
  and
• is light in colour. In polluted areas lichens
  are
• killed and bark is covered with soot and is dark
  in
• colour.
• Peppered moths can be either light or dark in
• colour. They feed at night and rest during the
  day
• on bark.
• Birds prey on the moths during the day.

3
Aim

• To illustrate the role of camouflage in natural
  selection

4
Method

• Moths of both types were cut out and pasted onto
  each background of the bark sheet
• Another person was asked to count the number of
  moths seen on each background when shown the
  sheet for only 5 seconds
• All results were entered in the table

5
Results
6
Interpretation

• The moths which would be most likely to be
• preyed upon in
• Unpolluted areas are the dark ones
• Polluted areas are the light ones

7

• The moths which would be most likely to
• survive in
• Unpolluted areas are the light ones
• Polluted areas are the dark ones

8
Conclusion

• These results suggest that moths which are
• camouflaged would survive and so shows the
• role of camouflage in natural selection

9
Evaluation

• The results could be made more reliable by
• pooling the results from other groups