Vestigial organs are __________.

• A. evidence for Lamarck's theory of use and disuse
• B. one piece of evidence that does not support the theory of evolution
• C. examples of anatomical imperfections such as the human knee
• D. homologies that can only be observed in embryos
• E. remnants of structures that were useful to an organism's ancestors but that are now nonfunctional or show reduced function

Answer: (E)

Verified step by step guidance

1. Understand the concept of vestigial organs: Vestigial organs are anatomical structures that have lost most or all of their original function through the process of evolution. They are remnants of structures that were fully functional in the organism's ancestors.
2. Consider the role of vestigial organs in evolutionary biology: These organs provide evidence for the theory of evolution, as they demonstrate how species have changed over time and adapted to new environments, leading to the reduction or loss of certain functions.
3. Evaluate the options given in the problem: Analyze each option to determine which one accurately describes vestigial organs. Consider whether they support evolutionary theory, are examples of anatomical imperfections, or are observable only in embryos.
4. Identify the correct description: Vestigial organs are not evidence for Lamarck's theory of use and disuse, nor are they solely anatomical imperfections or observable only in embryos. They are best described as remnants of structures that were useful to an organism's ancestors but are now nonfunctional or have reduced function.
5. Conclude with the correct understanding: Recognize that vestigial organs are important in understanding evolutionary history and the changes that occur in species over time, supporting the theory of evolution by demonstrating how certain traits become obsolete as species adapt to new environments.