Question

Explain industrial melanism.

What is industrial melanism?

Answer 1

Industrial melanism is the phenomenon in which dark-coloured forms of a species become more common in polluted industrial areas. A classic example is the peppered moth (Biston betularia).

Before industrialisation, light-coloured moths were more common because they were camouflaged against lichen-covered tree trunks. Industrial pollution caused soot to darken the tree trunks. As a result, dark-coloured moths became better camouflaged and were less likely to be eaten by birds, while light-coloured moths became more conspicuous.

Thus, the increase in dark-coloured moths due to industrial pollution demonstrates natural selection and evolution.