Question

Explain natural selection with example of industrial melanism.

Hint:

Industrial melanism is a classic example of directional selection, where one phenotype becomes favored due to environmental shifts.

Answer 1

Step 1: Natural selection, proposed by Charles Darwin, is the process where organisms with traits better suited to their environment survive and reproduce more successfully, passing these traits to offspring. Over time, these traits become more common in the population. Step 2: Industrial Melanism Example: In pre-industrial England, peppered moths (Biston betularia) were predominantly light-colored, blending with lichen-covered trees, avoiding predation by birds. During the Industrial Revolution, soot darkened trees, reducing lichen. The rare dark (melanic) moths, better camouflaged on dark trees, survived and reproduced more, increasing their frequency. Post-pollution control, light moths regained dominance as trees lightened, showing natural selection driven by environmental changes.