In 1977 an island in which hundreds of finches lived experienced a massive draug
ID: 72479 • Letter: I
Question
In 1977 an island in which hundreds of finches lived experienced a massive draught. Before the draught, the finches enjoyed eating small seeds. The draught caused the seeds to become big and hard making it difficult for the finches to eat - consequently resulting in the death of 85% of them. The surviving finches had larger beaks (making it easier to eat the big hard seeds), these remaining finches passes this trait on to the next generation.
Natural selection requires genetic variation, competition for limited resources, over production of offspring, and unequal reproductive success. A subset of finches taht are capable of eating large seeds are an example of which requirement? (1) Unequal reproductive success (2) Genetic variation (3) competition for limited resources or (4) overproduction of offspring?
Explanation / Answer
(2) Genetic variation
In this case, the population is not died because of limited resources or overpopulation or reproductive inequalities. But those that fail to take large seeds as food are died and those that are capable of eating large seeds survived, this is because genetic variation.