Question

Modern birds and mammals share an ancient common ancestor that was terrestrial, but penguins and whales both have limbs adapted for swimming.
Which of the following terms best describes the relationship between the bones in the forelimbs of penguins and whales?

• A. Homologous structures
• B. Analogous structures
• C. Vestigial organs
• D. None of the above

Answer 1

Answer: (B)

Analogous structures

Homologous structures are those structures which have common ancestors but have different functions.

Modern birds and mammals share an ancient common ancestor that was terrestrial.

Analogous structures are those structures that have different ancestors but perform the same functions. Limbs of penguins and whales both have adapted for swimming.

Vestigial organs are those organs which have almost lost their original function. Appendix in human is a vestigial organ.

Thus, the correct answer is 'analogous structures.'