Animals living in colder region have shorter tail and ears as compared to the animals living in warmer regions. This phenomenon is called

Options

A. Allen's law
B. Jordan's law
C. Dollo's law
D. Gloger's law

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that animals living in colder regions have shorter tails and ears compared to those in warmer regions. We need to identify the phenomenon that explains this observation.

2. **Identifying the Options**: The options provided are:
- Allen's law
- Jordan's law
- Dallow's law
- Flaugher's law

3. **Explaining the Phenomenon**: The phenomenon being described relates to the adaptation of animals to their environments. In colder regions, animals tend to have shorter extremities (tails and ears) to minimize heat loss. Conversely, animals in warmer regions have longer extremities to help dissipate excess body heat.

4. **Understanding Allen's Law**: Allen's law specifically states that endothermic animals (warm-blooded) in colder climates tend to have shorter appendages (like tails and ears) compared to their counterparts in warmer climates. This adaptation helps them conserve body heat.

5. **Conclusion**: Since the question describes the phenomenon of animals adapting their body extremities based on temperature, and since Allen's law is the correct term for this adaptation, we conclude that the answer is **Allen's law**.

**Final Answer**: The phenomenon is called **Allen's law**.

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