Question

Which of the following can be concluded from the Grants' long-term study of the medium ground finch on Daphne Major:

A. The strength of selection varies over time.
B. The direction of selection varies over time.
C. Beak size should continue to get larger over time.
D. A and B are correct.
E. A and C are correct.

Answer 1

The Grants' long-term study of the medium ground finch on Daphne Major provides evidence for the strength and direction of selection varying over time.

Step-by-step explanation:

The Grants' long-term study of the medium ground finch on Daphne Major provides evidence for both factors A and B. During a drought period in 1977, the vegetation on the island was altered, causing a decline in small, soft seeds. The large-billed birds were able to survive better than the small-billed birds, indicating that the strength and direction of selection varies over time.

Based on the study, it can be concluded that the Grants' long-term study demonstrates that the strength of selection and the direction of selection can vary over time, supporting option D.