The 'Recapitulation Theory' was put forth by

Options

A. Haeckel
B. Cuvier
C. Wallace
D. Lamarck

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of the 'Recapitulation Theory' and who proposed it.

2. **Defining Key Terms**:
- **Ontogeny**: This term refers to the development of an individual organism from its earliest stage (embryo) to maturity.
- **Phylogeny**: This term refers to the evolutionary history and development of a species or group of organisms.

3. **Explaining Recapitulation Theory**:
- The Recapitulation Theory, also known as the Biogenetic Law, posits that during its development (ontogeny), an individual organism goes through stages that resemble the adult forms of its ancestors. In simpler terms, it suggests that the development of an individual mirrors the evolutionary history of its species.

4. **Identifying the Proponent**:
- The theory was proposed by Ernst Haeckel in 1866.

5. **Conclusion**: Therefore, the correct answer to the question is Ernst Haeckel.

**Final Answer**: The 'Recapitulation Theory' was put forth by Ernst Haeckel.

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