A population splits into two or more groups and these groups occupy the different ecological zones. This is known as

Options

A. Allopatric speciation
B. Sympatric speciation
C. Ecological speciation
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question describes a scenario where a population splits into two or more groups that occupy different ecological zones. We need to identify the term that describes this phenomenon.

2. **Identifying Types of Speciation**: There are different types of speciation, including:
- Allopatric speciation
- Sympatric speciation
- Ecological speciation

3. **Defining Allopatric Speciation**: Allopatric speciation occurs when a population is divided by a physical barrier (like mountains, rivers, etc.), leading to the groups evolving independently in different environments. This results in the formation of new species due to the lack of gene flow between the separated populations.

4. **Defining Sympatric Speciation**: Sympatric speciation occurs without a physical barrier. Instead, it happens when populations within the same area diverge due to genetic mutations or ecological niches that lead to reproductive isolation.

5. **Defining Ecological Speciation**: Ecological speciation involves the formation of new species due to different environmental pressures and natural selection, leading to adaptations that cause reproductive isolation.

6. **Analyzing the Given Scenario**: The question specifically mentions that the population splits and occupies different ecological zones. This aligns with the definition of allopatric speciation, where a barrier leads to the separation of populations into distinct ecological zones.

7. **Conclusion**: Based on the definitions and the scenario described, the correct answer is **allopatric speciation**.

**Final Answer**: Allopatric speciation.

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