Question

The peppered moth provides a well-known example of natural selection. The light-coloured form of the moth was predominant in England before the industrial revolution. In the mid-nineteenth century, a dark- coloured orm appeared. The difference is produced by a dominant allele of one gene. By about 1900, approximately 90% of the moths around industria areas were dark coloured whereas ght-coloured moths were still abundant elsewhere. Apparently, birds could readily find the light moths against the soot-darkened background in industrial areas and therefore were eating more light moths. Recently, use of cleaner fuels has greatly reduced soot in the landscape. What would you expect to happen to colored morphs in the population? Both colour morphs should decrease in frequency Both colour morphs should increase in frequency The light morph should decrease in frequency and the dark morph increase in frequency due to selection No change in morph toquencies OThe dark morph should decrease in frequency and the light morph increase in frequency due to selection

Answer 1

The correct answer is E. The dark morph should decrease in frequency and the light morph increase in frequency due to selection.

Step-by-step explanation:

According to natural selection and evolution principles, organisms with traits that represent an advantage for surviving and/or reproducing are more likely to prevail over time. In the case presented, it implies light morphs should increase in frequency because due to less soot on the air, it is expected the bark of trees and other elements are lighter, and therefore in this background dark morphs will survive less as they can be spotted in the light background.

As a result, the population of dark morphs will decrease as well as their possibilities to reproduce while white morphs population increases as they can reproduce and pass their genes to new generations including the color trait that represents a surviving advantage. Thus, in this case, "the dark morph should decrease in frequency and the light morph increase in frequency due to selection".