Question

Explain industrial melanism.

Answer 1

Industrial Melanism: Industrial melanism is an example of natural selection. It illustrates the
development of dark coloured peppered moths in response to air pollution during the industrial revolution in Great Britain.

Before the industrial revolution (1845) light-coloured peppered moths called Biston Betularia were prevalent in very high numbers. The peppered moths are nocturnal in habit. During daytime, they rest on the tree trunk. Their pale body colour camouflaged well with the lichen-covered trees that helped them to escape from the predatory birds. On the contrary, the black coloured moth called Biston carbonaria, resting on lichen covered tree trunks were very Conspicuous and were easy victims for the predatory birds hence they were rare.

During the industrial revolution, the large number of industries came up in Great Britain. The industries released black sooty smoke that killed the lichens growing on trees and turned the trees black due to the sooty deposit. This change became an advantage to the black tree trunks and their population increased, while the pale coloured moths became easy victims to predatory birds and their population
drastically reduced.

Thus, natural selection has resulted in the establishment of a phenotypic trait in changing the environmental conditions.