How do homologous structures provide evidence for evolution?

• A. They show that species are unrelated because the structures perform different functions in different environments.
• B. They indicate that different species share a common ancestor because the structures have similar underlying anatomy despite different functions.
• C. They prove evolution occurs only through mutations in mitochondrial DNA rather than changes to anatomy.
• D. They demonstrate that organisms evolve identical structures independently due to similar selective pressures (convergent evolution).

Answer: (B)

Verified step by step guidance

1. Understand the concept of homologous structures: these are anatomical features in different species that have similar underlying structures but may serve different functions.
2. Recognize that homologous structures arise because species share a common ancestor, and these structures have been inherited and modified over time.
3. Analyze how the presence of similar bone arrangements or organ structures in diverse species suggests evolutionary relationships despite differences in function.
4. Contrast homologous structures with analogous structures, which perform similar functions but do not share a common ancestral origin, to clarify the evidence for common ancestry.
5. Conclude that homologous structures provide evidence for evolution by demonstrating that different species have evolved from a common ancestor, adapting their shared anatomy to different environments and functions.