Appearance of some ancestral traits in certain individuals of a species is called `:`

Options

A. analogy
B. reversion
C. homology
D. recapitulation

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Question**: The question asks for the term that describes the appearance of ancestral traits in certain individuals of a species. This phenomenon indicates that some traits that were present in the ancestors of a species can reappear in some modern individuals.

2. **Identifying Key Terms**: The key terms in the question are "ancestral traits" and "appearance." We need to find a biological term that fits this description.

3. **Exploring Possible Answers**:
- **Reversion**: This term refers to the reappearance of ancestral traits in a descendant species. It suggests that certain traits that were lost in the evolutionary process can reappear.
- **Homology**: This refers to traits that are similar due to shared ancestry but does not specifically address the reappearance of traits.
- **Analogies**: This refers to traits that serve similar functions but do not share a common ancestry, which is not relevant to the question.
- **Recapitulation**: This term refers to the idea that the development of an individual organism (ontogeny) follows the same progression as the evolutionary history of that organism (phylogeny), which is also not what the question is asking.

4. **Selecting the Correct Answer**: Based on the definitions and explanations, the term that best describes the appearance of ancestral traits in certain individuals of a species is **Reversion**.

5. **Final Answer**: The answer to the question is **Reversion**.

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