Question

In Europe, dark peppered moths were rare before the 1850's and light-colored moths were plentiful. After the industrial revolution, pollution covered the tree trunks where the moths lived. The light moths declined in number and the dark-colored moths increased in number. Which of the following explains what happened to the two moth populations?

A. The trees became lighter, and since the light

B. The dark-colored moths did not blend in well on the light-colored trees and were left alone by the birds.

C. The dark-colored moths blended in better on the dark-colored trees and were eaten more by the birds

D. The trees became darker, and since the light-colored moths could not adapt to the change in their environment, they were easily seen and eaten by the birds.

Answer 1

Answer:

The evolution of the peppered moth is an evolutionary instance of directional colour change in the moth population as a consequence of air pollution during the Industrial Revolution. The frequency of dark-coloured moths increased at that time, an example of industrial melanism.

Answer 2

The correct option is- D. The trees became darker, and since the light-coloured moths could not adapt to the change in their environment, they were easily seen and eaten by the birds.

• This is because, before the industrial revolution, the tree trunks were light in colour that favoured the population of light-coloured moths. These moths camouflage with the light tree trunks and hence, cannot be seen by their predators (birds).
• After industrial revolution, due to air pollution, the tree trunks became darker and hence, the light coloured moths were easily seen by their predators. Some moths adapted themselves to the changing environment and they became dark colored. This favoured the population of dark coloured moths by protecting them from the birds.
• This is an example of natural selection that favoured the growth of dark coloured moths.