Question

separated species
a population of mice live in a light, sandy environment. the majority of mice have light - colored fur, and the remaining mice have either medium - colored fur or dark - colored fur. a flood occurs in the area, creating a river that separates the population and changes the color of the ground on either side. after a long period of time, the water dries up and the two groups of mice are able to interact again. after the change, mice from different sides are unable to breed with each other. the pictures show the environment before, during, and after the change.
original environment environments after separation by water environment after water dries up
the table shows the frequency of fur color across the populations when the mice were separated by the water.
which two things occurred as a result of the environmental change?
□ a. the frequency for dark - colored fur increased on the north side.
□ b. the frequency for light - colored fur increased on the north side.
□ c. the frequency for medium - colored fur increased on the south side.
□ d. the frequency for medium - colored fur increased on the north side.
□ e. the frequency for dark - colored fur increased on the south side.

Explanation:

1. For the north side: Track medium fur frequency: Gen1=12%, Gen15=87% → large increase.
2. For the south side: Track dark fur frequency: Gen1=5%, Gen15=84% → large increase.
3. Other options do not match the data trends in the table.

Answer:

D. The frequency for medium-colored fur increased on the north side.
E. The frequency for dark-colored fur increased on the south side.