Question

Industrial melanism provides a good example of natural selection. Discuss.

Answer 1

• The best example is industrial melanism showing the effect of industrial pollution on the moth population on a nearby tree.
• Before industrialisation, light-coloured lichen used to grow on trees and moth predators could not spot white moths easily, while dark moths were lesser in the moth population. However, due to industrial pollution, lichens could not grow on trees and it became difficult for predators to spot dark moths on the dark background of the stem bark, and thus, the population of white moths became less than that of dark moths.
• This process is termed industrial melanism. Before industrialisation, white moths were better adapted towards nature, but after industrialisation, dark-coloured moths were more fit towards the changed environmental conditions.