Related population occupying the same isolated territory side by side are called .............species

Options

A. Allopatric
B. Sympatric
C. Quantum
D. Parapatric

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term used to describe related populations that occupy the same isolated territory side by side.

2. **Identifying the Options**: The options provided are:
- Allopatric
- Sympatric
- Quantum
- Parapatric

3. **Analyzing Allopatric Species**: Allopatric species arise when a part of a population becomes geographically isolated from the main population, leading to the formation of new species. Since the question specifies that the populations are side by side in the same territory, this option is incorrect.

4. **Analyzing Sympatric Species**: Sympatric species occur when a small segment of a population becomes reproductively isolated from the rest of the population without geographical barriers. However, these populations do not necessarily occupy the same isolated territory side by side, making this option incorrect as well.

5. **Analyzing Quantum Species**: Quantum speciation refers to a rapid and abrupt formation of a new species that is significantly different from its ancestors. This concept does not relate to the populations living side by side, so this option is also incorrect.

6. **Analyzing Parapatric Species**: Parapatric species occur when populations are adjacent to each other and may have overlapping territories but are still somewhat isolated due to habitat differences or other factors. This aligns with the description of populations living side by side in isolated territories.

7. **Conclusion**: The correct answer is "Parapatric species."

**Final Answer**: Related populations occupying the same isolated territory side by side are called **Parapatric species**.

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