Explain how natural selection operates in nature by taking an example of white winged and dark winged moths of England.

Explanation

In the nineteenth century it was noticed that in towns and cities it was actually the black form of the moth that was more common than the pale peppered form. Industrialisation and domestic coal fires had caused sooty air pollution which had killed off lichens and blackened urban tree trunks and walls. So, now it was the plae form of the moth that was more obvious to predators, while the melanic form was better camouflaged and more likely to survive and produce offspring. As a result, over successive generations, the black moths came to outnumber the pale forms in towns and cities.
Since, moths are short-lived, this evolution by natural selection happened quite quickly. For example, the first black Peppered Moth was recorded in Manchester in 1848 and by 1895 98% of Peppered Moths in the city were black.