Imagine that two men and two women settle on an uninhabited island, no new settlers arrive, and nobody leaves the island for many generations. All four of the settlers have brown eyes, but one of the men carries a recessive gene for blue eyes. Eye color has no effect on fitness. If the percentage of blue-eyed individuals on the island increases from 0% to 25%, what is the probable cause?
A) Natural selection
B) Genetic drift
C) Random mutation
D) Artificial selection

Question

Quizplus · Accepted Answer

Genetic drift is the most probable cause for the increase in the percentage of blue-eyed individuals in a small, isolated population where eye color has no effect on fitness. Genetic drift refers to random fluctuations in the frequencies of alleles (in this case, the allele for blue eyes) within a population. In small populations, these random changes can have a significant impact on the genetic makeup of the population over generations.

Imagine That Two Men and Two Women Settle on an Uninhabited