When darwin spoke of the struggle for existence and survival of the fittest in the nature he was convinced that

Options

A. intraspecific competition is a potent force in organic evolution
B. interspecific competition is a potent force in organic evolution
C. intensive reproduction is the potent force in organic evolution
D. intensive predation is the potent force in organic evolution

Answer

**Step-by-Step Solution:**

1. **Understanding Darwin's Concepts**: Begin by recognizing that Charles Darwin proposed two main concepts in his theory of evolution: branching descent and natural selection.

2. **Defining Natural Selection**: Natural selection is the process where organisms that are better adapted to their environment tend to survive and reproduce more than those that are less well adapted. This leads to the gradual evolution of species.

3. **Struggle for Existence**: The phrase "struggle for existence" refers to the competition among organisms for limited resources such as food, space, and mates. This struggle can occur both within a species (intraspecific competition) and between different species (interspecific competition).

4. **Identifying Key Forces in Evolution**: Darwin emphasized that competition, particularly intraspecific competition (competition within the same species), is a significant driving force in organic evolution. However, interspecific competition (competition between different species) also plays a crucial role.

5. **Conclusion on Darwin's Conviction**: When Darwin spoke of the struggle for existence and survival of the fittest, he was convinced that interspecific competition is a potent force in organic evolution. This means that the competition between different species influences which organisms survive and thrive in a given environment.

6. **Final Answer**: Therefore, the correct answer to the question is that Darwin was convinced that "interspecific competition is a potent force in organic evolution."

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