Question

Given alongside are two figures (A and B) showing a phenomenon that was first observed in Manchester before and after the year 1850.

Answer the following:

Briefly mention why the changes shown in the two figures appeared.

Answer 1

1. Before the Industrial Revolution in England, white-winged moths were more common than dark-winged moths. Lower pollution levels resulted in lighter tree trunks due to lichen. White-winged moths were not noticeable on light backgrounds, but dark-winged moths were easily eaten by predators.
2. Following industrialisation, dark-winged moths became more prevalent than white-winged moths.
3. During industrialisation, air pollution caused darkened tree trunks to have white lichens, making white-winged moths more visible.
4. White-winged moths lack camouflage, making them vulnerable to predators.
5. Nature selected the most suitable moths. However, none were totally exterminated.