According to Darwin, mechanism of evolution is

Answer

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

1. **Introduction to Charles Darwin**: Charles Darwin was a prominent scientist known for his contributions to the understanding of evolution.

2. **Theory of Evolution**: Darwin proposed the theory of evolution, which explains how species change over time.

3. **Mechanism of Evolution**: The primary mechanism that Darwin identified for evolution is known as "natural selection."

4. **Explanation of Natural Selection**: According to Darwin, natural selection occurs when there are changes in the environment or climate. Organisms possess various traits, and those traits that are advantageous in a given environment are more likely to be passed on to the next generation.

5. **Survival of the Fittest**: The traits that favor survival in changing conditions are naturally selected. Organisms with these beneficial traits are more likely to survive and reproduce, while those without these traits may not survive.

6. **Conclusion**: Therefore, according to Darwin, the mechanism of evolution is best described as "natural selection."

**Final Answer**: According to Darwin, the mechanism of evolution is natural selection.

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