If a variety of light colored moths and dark colored moths lived in a forest of trees with a lighter colored bark and the environment changed causing the bark to darken, what will likely happen to the frequency of the genes that control the light and dark colors?
A.
The frequency of the dark colored gene increases and the frequency of the light colored gene decreases.
B.
The frequency of the light colored gene increases and the frequency of the dark colored gene decreases.
C.
The gene frequency of the light and dark genes remain the same.
D.
The frequency of the dark colored gene stays the same and the frequency of the light colored gene increases.

Dark coloured moths will be better camouflaged and so better protected from predators. More of them will survive and reproduce, increasing the frequency of dark coloured genes.

Light coloured gene will provide less camouflage, those moths will be caught by predators more often and live to reproduce less. So the light coloured gene will decrease.

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