The pioneers in the field of 'organic evolution' are

Options

A. A.Darwin, Lamarck, Landsteiner ,and de Vries
B. B.Darwin , de Vries , Lamarck, Huxley
C. C.Lamarck, Landsteiner , Malthus, de Vries
D. D.Landsteiner , de Vries , Malthus, Darwin

Answer

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

1. **Understanding Organic Evolution**: Organic evolution refers to the gradual process through which living organisms have developed and diversified from simpler forms to more complex ones over time. This process involves changes in the characteristics of organisms, which are then passed down to subsequent generations.

2. **Key Theories of Organic Evolution**: Several theories have been proposed to explain the mechanisms of organic evolution. The most notable among these are:
- **Lamarckism**: Proposed by Jean-Baptiste Lamarck, this theory suggests that organisms can pass on traits acquired during their lifetime to their offspring.
- **Darwinism**: Proposed by Charles Darwin, this theory emphasizes natural selection as the primary mechanism of evolution, where organisms better adapted to their environment tend to survive and reproduce.
- **Mutational Theory**: Proposed by Hugo de Vries, this theory focuses on mutations as the source of genetic variation that drives evolution.

3. **Identifying the Pioneers**: The pioneers in the field of organic evolution include:
- **Charles Darwin**: Known for his theory of natural selection.
- **Jean-Baptiste Lamarck**: Known for his early ideas on evolution and inheritance of acquired characteristics.
- **Hugo de Vries**: Known for his work on mutations and their role in evolution.
- **Thomas Henry Huxley**: Known as "Darwin's Bulldog" for his defense of Darwin's theories.

4. **Conclusion**: Based on the contributions of these scientists, the pioneers in the field of organic evolution are Charles Darwin, Hugo de Vries, Jean-Baptiste Lamarck, and Thomas Huxley.

**Final Answer**: The pioneers in the field of organic evolution are Darwin, Hugo de Vries, Lamarck, and Huxley.

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