MDCAT Biology MCQ #3646

In a population of finches on an island, a severe drought leads to a scarcity of small seeds, resulting in the survival of finches with larger beaks. What is the primary mechanism driving this evolutionary change?

MDCAT Biology MCQ #3646

  1. Question 1

    Q1. In a population of finches on an island, a severe drought leads to a scarcity of small seeds, resulting in the survival of finches with larger beaks. What is the primary mechanism driving this evolutionary change?

    • A) Genetic drift due to the bottleneck effect
    • B) Natural selection acting on beak size
    • C) Mutation introducing a new beak size gene
    • D) Gene flow from a neighboring island

    Answer: Natural selection acting on beak size

    Explanation: Natural selection favors larger beaks, most tempting wrong option fails as genetic drift is random.