Question

until the middle of the 19th century, all peppered moths (biston betularia) observed around manchester, england, were light in color. in 1845, a single black peppered moth was reported. as manchester became more industrialized and dark soot began to cover the bark of the trees, the frequency of black moths increased greatly. the change in proportion of light and dark forms resulted from:

Answer 1

The increase of dark-colored peppered moths in industrial Manchester is due to directional selection, with industrial melanism making dark moths better camouflaged and less prone to predation.

Step-by-step explanation:

The change in the proportion of light and dark forms of the peppered moth (Biston betularia) around Manchester, England, during the Industrial Revolution is a classic example of directional selection. The originally common light-colored moths were well-camouflaged against the pristine environment, whereas the rare dark-colored moths stood out, making them easy prey for birds. However, as industrialization increased and soot began to cover tree bark, the dark moths became better camouflaged and thus less likely to be eaten by predators. This shift in the moth population from light to dark is also known as industrial melanism, a term referring to the darkness of their coloration increasing due to industrial factors.