MP Board · Class 12 · Biology · EvolutionExplain Industrial Melanism in the peppered moth (Biston betularia) as an example of natural selection in action.

Industrial Melanism in the peppered moth (Biston betularia) in England serves as a classic demonstration of natural selection driven by human-induced environmental changes. \nBefore industrialization in the 1850s, light-colored (white-winged) moths were far more abundant than dark-colored (melanic) moths. The bark of tree trunks was covered with light-colored lichens. Light moths blended seamlessly with the lichens, camouflaging them from predatory birds, whereas dark moths were easily spotted and preyed upon. \nHowever, following rapid industrialization, soot and coal smoke from factories killed the lichens and covered the tree trunks with dark soot. In this altered environment, the dark moths gained a distinct selective survival advantage because they were hidden against the soot-covered bark, while light moths became highly conspicuous to predators. \nConsequently, dark moths survived in larger numbers and reproduced, causing a sharp increase in the frequency of dark moths in industrial areas. This shift clearly demonstrates that natural selection favors phenotypes with better survival adaptations in changing environments.