Final answer:
The study of peppered moths showed evolutionary change via directional selection, where the Industrial Revolution led to darker moths being favored due to better camouflage against soot-covered trees, exemplifying natural selection.
Step-by-step explanation:
The long-term study of peppered moths demonstrated evolutionary change due to directional selection. As the environment changed because of the Industrial Revolution, and trees became covered in soot, the previously prevalent light-colored peppered moths became more visible to predators. Consequently, the dark-colored moths that had a mutation for melanic (dark) coloration were better camouflaged against the sooty trees, thus had a higher survival rate, and their numbers increased in the population. Over time, this shift in coloration of the moths is a classic example of natural selection, where the traits that improve survival in a given environment become more common in the population.