Shorter body extremities in animals living in colder climate is explained by

Options

A. Allen's rule
B. Bergman's rule
C. Gloger's rule
D. Jordan's rule

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the reason behind shorter body extremities in animals that live in colder climates. We need to identify which ecological rule explains this phenomenon.

2. **Identifying the Options**: The options provided are:
- A) Allen's rule
- B) Bergmann's rule
- C) Gloger's rule
- D) Jordan's rule

3. **Explaining Allen's Rule**: Allen's rule states that animals living in colder climates tend to have shorter limbs and body extremities compared to those in warmer climates. This adaptation helps to conserve body heat.

4. **Explaining Bergmann's Rule**: Bergmann's rule suggests that larger body sizes are found in colder environments. This is because larger bodies have a smaller surface area-to-volume ratio, which helps in retaining heat.

5. **Explaining Gloger's Rule**: Gloger's rule states that animals in more humid and warmer regions tend to have darker pigmentation, while those in colder and drier areas have lighter pigmentation.

6. **Explaining Jordan's Rule**: Jordan's rule pertains to aquatic animals, indicating that those in colder waters tend to have more fins and scales for protection and adaptation to their environment.

7. **Choosing the Correct Answer**: Given the explanations, Allen's rule directly addresses the question regarding shorter body extremities in animals living in colder climates. Therefore, the correct answer is **A) Allen's rule**.

**Final Answer**: The shorter body extremities in animals living in colder climates is explained by **Allen's rule**.

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