The peppered moth, Biston betularia, occurs as light or dark-colored variants. Prior to the Industrial Revolution, the light-colored moths were more prevalent because they could camouflage well on lichen-covered trees. With the advent of the Industrial Revolution and increasing air pollution, dark-colored moths became more prevalent. What is the type of evolutionary force at work? Why do the darker maths become more prevalent?

Question

The peppered moth, Biston betularia, occurs as light or dark-colored variants. Prior to the Industrial Revolution, the light-colored moths were more prevalent because they could camouflage well on lichen-covered trees. With the advent of the Industrial Revolution and increasing air pollution, dark-colored moths became more prevalent. What is the type of evolutionary force at work? Why do the darker maths become more prevalent?

O directional selection, because lighter maths were killed by the air pollution

directional selection, because darker moths escaped being spotted by predators

genetic drift, because lighter mathe ware illed by the air pollution

genetic drift, because darker moths escaped being spotted by predators

(1 point)

Answer 1

The type of evolutionary force at work in this scenario is directional selection. The darker moths become more prevalent because they are able to better camouflage against the now polluted trees, whereas the lighter moths stand out more and are more easily spotted by predators. Therefore, the dark-colored moths have a survival advantage in this new environment, leading to an increase in their population over time.