Species originate discontinuously without intermediate forms according to

Options

A. Lamarck
B. de Vries
C. Darwin
D. Haeckel

Answer

To answer the question "Species originate discontinuously without intermediate forms according to," we will analyze the theories proposed by various scientists and determine which one aligns with the statement.

### Step-by-Step Solution:

1. **Understanding the Question**: The question is asking about the origin of species in a way that they appear suddenly and do not have intermediate forms. This suggests a theory that supports abrupt changes rather than gradual evolution.

2. **Identifying the Theories**:
- **Lamarck's Theory**: Lamarck proposed that species evolve gradually through the inheritance of acquired characteristics. This theory does not support the idea of discontinuous origin as it emphasizes gradual changes over time.
- **Darwin's Theory**: Darwin is known for his theory of natural selection, which explains how species adapt to their environment over time through gradual changes. Like Lamarck, this does not align with the concept of discontinuous origin.
- **De Vries' Mutation Theory**: Hugo de Vries introduced the concept of mutations as a source of variation in species. His theory suggests that species can originate through sudden mutations, leading to significant changes without intermediate forms. This aligns perfectly with the question's premise.
- **Haeckel's Biogenetic Law**: Ernst Haeckel's law relates to the development of organisms and evolutionary biology but does not specifically address the discontinuous origin of species.

3. **Conclusion**: Based on the analysis, the theory that best fits the statement "Species originate discontinuously without intermediate forms" is **De Vries' Mutation Theory**.

### Final Answer:
Species originate discontinuously without intermediate forms according to **De Vries' Mutation Theory**.

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