Which of the following factors has not aided in the high species diversity of tropics

Options

A. Less seasonal variation promoting niche specialisation
B. Availability of more solar energy
C. More pest pressure
D. Less migration

Answer

To solve the question, "Which of the following factors has not aided in the high species diversity of tropics?" we can break down the reasoning into several steps:

### Step 1: Understand the Context
The question is asking about factors that contribute to high species diversity in tropical regions. We need to evaluate each option provided to determine which one does not contribute positively to biodiversity.

### Step 2: Analyze Each Factor
1. **Time for Speciation**: The tropics have not experienced frequent glaciations compared to temperate regions, allowing for longer periods of evolutionary development. This factor promotes species diversity.

2. **Less Seasonal Variation**: A stable environment with less seasonal variation allows organisms to specialize in their niches. This stability promotes adaptation and increases biodiversity.

3. **Availability of Solar Energy**: The tropics receive more solar energy, which supports higher productivity. High productivity means more resources are available for various species, thus supporting greater biodiversity.

4. **More Pest Pressure**: Increased pest pressure typically leads to a decrease in biodiversity, as it can harm populations of various species. This factor does not aid in increasing species diversity.

### Step 3: Identify the Incorrect Factor
From the analysis, we can see that:
- Options 1, 2, and 3 contribute positively to species diversity.
- Option 4 (More Pest Pressure) does not aid in increasing biodiversity; instead, it can reduce it.

### Conclusion
The factor that has not aided in the high species diversity of the tropics is **More Pest Pressure**.

### Final Answer
**Option 3: More Pest Pressure** is the correct answer.

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