Warm blooded animals like mammals from colder climates generally have shorter ear and limbs . This is an explanation of

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that warm-blooded animals, specifically mammals from colder climates, tend to have shorter ears and limbs. We need to identify which biological rule explains this phenomenon.

2. **Identifying the Options**: The options provided are:
- First: Jordan's Rule
- Second: Allen's Rule
- Third: Wren's Rule
- Fourth: Bergman's Rule

3. **Analyzing Jordan's Rule**: Jordan's Rule pertains to the number of vertebrae in fish, which increases in colder regions and decreases in warmer regions. This rule does not relate to the physical characteristics of mammals, so it can be eliminated.

4. **Analyzing Allen's Rule**: Allen's Rule states that endothermic (warm-blooded) animals from colder climates tend to have shorter appendages (like ears and limbs) compared to those from warmer climates. This adaptation helps reduce heat loss, making it the most relevant explanation for the question.

5. **Analyzing Wren's Rule**: Wren's Rule deals with the wing shapes of birds, where narrower wings are found in colder regions and broader wings in warmer regions. This rule does not apply to the characteristics of mammals, so it can also be eliminated.

6. **Analyzing Bergman's Rule**: Bergman’s Rule states that within a species, individuals in colder climates tend to be larger in body size compared to those in warmer climates. This rule does not explain the shorter ears and limbs, so it can be eliminated as well.

7. **Conclusion**: Based on the analysis, the correct explanation for the observation that warm-blooded animals from colder climates have shorter ears and limbs is **Allen's Rule**.

**Final Answer**: The correct explanation is **Allen's Rule**.

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