Suppose children of a brown-eyed pair and a blue-eyed couple have either brown or blue eyes. Brown eyes are the dominant allele, thus even though there is a 50% possibility of having blue eyes, all the children may end up having brown eyes by chance in subsequent generations. This is an example of which effect?
Bottleneck Effect
Founder effect
Gene flow
Genetic Drift
The allele frequency rises if the allele has an impact on the organism that leads to increased DNA replication. The allele frequency falls if the organism is harmed by the allele. Genetic drift occurs when the allele frequency changes as a result of the presence of an unrelated organism that managed to survive. Hence, option 4 is the correct answer.