Animals that possess homologous structures probably:

• A. perform the same function with those structures
• B. have identical DNA sequences
• C. live in the same environment
• D. evolved from a common ancestor

Answer: (D)

Verified step by step guidance

1. Understand the concept of homologous structures: Homologous structures are anatomical features that are similar in structure but may serve different functions in different organisms. These similarities suggest a shared evolutionary origin.
2. Recognize the significance of homologous structures: The presence of homologous structures indicates that the organisms possessing them likely share a common ancestor, as these structures were inherited and modified over time through evolution.
3. Eliminate incorrect options: Homologous structures do not necessarily perform the same function (e.g., a bat's wing and a human's arm have different functions). They also do not imply identical DNA sequences, as genetic variation occurs over time. Additionally, organisms with homologous structures do not have to live in the same environment, as evolution can lead to adaptations to different habitats.
4. Focus on the correct reasoning: The key takeaway is that homologous structures are evidence of evolutionary relationships, pointing to a shared ancestry rather than functional or environmental similarities.
5. Conclude that the correct answer is: 'evolved from a common ancestor,' as this aligns with the definition and significance of homologous structures in evolutionary biology.