Which of the following best describes Charles Darwin's observations of finches on the Galápagos Islands that contributed to his theory of natural selection?

• A. He noted that finches migrated to the islands every year from the mainland.
• B. He discovered that finches on the islands did not reproduce due to lack of food.
• C. He observed that finches on different islands had beaks adapted to specific food sources.
• D. He found that all finches on the islands had identical beak shapes regardless of their diet.

Answer: (C)

Verified step by step guidance

1. Step 1: Understand the context of the problem. Charles Darwin's observations of finches on the Galápagos Islands were pivotal in developing his theory of natural selection. His observations focused on how traits, such as beak shape, varied among finches depending on their environment and food sources.
2. Step 2: Analyze the options provided. The first option suggests migration, which is not relevant to Darwin's observations. The second option mentions reproduction issues, which were not part of his findings. The third option highlights adaptation of beak shapes to food sources, which aligns with Darwin's observations. The fourth option states identical beak shapes, which contradicts his findings.
3. Step 3: Recall the concept of natural selection. Natural selection is the process by which organisms with traits better suited to their environment are more likely to survive and reproduce. Darwin observed that finches on different islands had beaks adapted to specific food sources, demonstrating this principle.
4. Step 4: Relate the observations to the theory. Darwin's observation of finches with different beak shapes adapted to their diets provided evidence that traits can evolve over generations in response to environmental pressures.
5. Step 5: Conclude that the correct description of Darwin's observations is: 'He observed that finches on different islands had beaks adapted to specific food sources,' as this directly supports the concept of natural selection.