Question

"Appearance of melanised moths post-industrialisation in England is a classic example of evolution by natural selection." Explain. [3 Marks]

Answer 1

Before industrialisation, the population of light coloured moth were predominant. They were easily camouflaged on the tree trunks and so could escape from the predators. The dark coloured moth were easily caught by the predators as they were not camouflaged on light brown tree trunks. Light coloured moths were naturally selected against the dark coloured ones. [1.5 Marks]
Post industrialisation in England, due to more pollution, soot and smoke got deposited on tree trunks. The light coloured moths were exposed on dark tree trunks and easily caught by the predators. The dark-winged or melanised moth survived and their numbers increased. Hence, appearance of melanised moths post-industrialisation in England is a classic example of evolution by natural selection. [1.5 marks]