Question

Two European men and two Polynesian women settled on a previously uninhabited tropical island. All four of the settlers have brown eyes, a dominant trait, but one of the Europeans is heterozygous and carries the recessive gene for blue eyes.
No new settlers arrive,and nobody leaves the island.After a few generations,the percentage of blue-eyed individuals increases from the original zero to 25 percent.This is probably due to which of the following factors?
A) genetic drift
B) mutation
C) gene flow

Answer 1

Answer:

Two European men and two Polynesian women settled on a previously uninhabited tropical island. All four of the settlers have brown eyes, a dominant trait, but one of the Europeans is heterozygous and carries the recessive gene for blue eyes.  No new settlers arrive,and nobody leaves the island.After a few generations,the percentage of blue-eyed individuals increases from the original zero to 25 percent.This is probably due to which of the following factors?

genetic drift

Explanation:

Genetic drift entails when there are changes in the gene frequency which occur in a gene that is existing. From the analogy above, it is a known fact that only gneetic drift could allow such to happen as mutation will only occur with a sudden change of gene which is not the case described above