Let's analyze the results step by step based on the provided data:
### Initial and Final Populations:
#### Light-colored Trees:
- Starting Population:
- Light-colored moths: 20
- Dark-colored moths: 20
- Ending Population:
- Light-colored moths: 25
- Dark-colored moths: 15
#### Dark-colored Trees:
- Starting Population:
- Light-colored moths: 20
- Dark-colored moths: 20
- Ending Population:
- Light-colored moths: 5
- Dark-colored moths: 35
### Calculating the Changes in Population:
#### Light-colored Trees:
- Change in light-colored moths:
[tex]\[
25 - 20 = 5
\][/tex]
- Change in dark-colored moths:
[tex]\[
15 - 20 = -5
\][/tex]
#### Dark-colored Trees:
- Change in light-colored moths:
[tex]\[
5 - 20 = -15
\][/tex]
- Change in dark-colored moths:
[tex]\[
35 - 20 = 15
\][/tex]
From these changes, we can observe:
1. In the light-colored tree environment:
- The population of light-colored moths increased by 5.
- The population of dark-colored moths decreased by 5.
2. In the dark-colored tree environment:
- The population of light-colored moths decreased by 15.
- The population of dark-colored moths increased by 15.
### Interpreting the Results:
- In the light-colored tree environment, light-colored moths had an increase in population, indicating they were better camouflaged and hence had higher survival rates.
- In the dark-colored tree environment, dark-colored moths had an increase in population, indicating they were better camouflaged and hence had higher survival rates.
Based on the above analysis, the results of this experiment show that the moths' fitness depended on the environment they were in. Specifically, light-colored moths were more fit in the light-colored tree environment.
Thus, the best description of the experimental results is:
D. The light-colored moths were more fit.
