A scientist who gave a theory very similar to that given by Darwin was
Or
Co-worker of Darwin was

Options

A. Wallace
B. Mendel
C. Bateson
D. Lamarck

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for a scientist whose theory was very similar to that of Charles Darwin or who was a co-worker of Darwin.

2. **Recall Key Figures in Evolution**: Charles Darwin is well-known for his theory of natural selection. It is important to consider other scientists who contributed to similar ideas around the same time.

3. **Consider Alfred Russel Wallace**: Alfred Russel Wallace is a significant figure in the field of evolutionary biology. He independently developed a theory of natural selection that closely mirrored Darwin's ideas.

4. **Research Wallace's Contributions**: Wallace conducted extensive research on the diversity of plants and animals, particularly in the Malay Archipelago. His findings led him to the same conclusions as Darwin regarding evolution and natural selection.

5. **Publication of Wallace's Work**: Wallace published a paper titled "Contributions to the Theory of Natural Selection" in 1858, which was presented to the Linnean Society of London at the same time as Darwin's work.

6. **Conclusion**: Therefore, the correct answer to the question is that the scientist who gave a theory very similar to that of Darwin and was a co-worker of Darwin is Alfred Russel Wallace.

**Final Answer**: Alfred Russel Wallace.

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