Which of the following is an important adaptation of animals to cold climate

Options

A. Thin layer of body fat
B. Aestivation
C. Increased tendency to shiver
D. Reduced surface area to volume ratio

Answer

**Step-by-Step Solution:**

1. **Understanding Adaptation**: Adaptation refers to the characteristics that enable organisms to survive and reproduce in their specific environments. These adaptations can be morphological (physical structure), physiological (internal processes), or behavioral (actions).

2. **Cold Climate Challenges**: In cold climates, animals face the challenge of maintaining their body temperature. The external environment is cold, and to survive, animals must find ways to conserve heat.

3. **Evaluating Options**:
- **Option A: Thin layer of body fat** - This is incorrect. Animals in cold climates typically have a thick layer of body fat to insulate against the cold.
- **Option B: Estivation** - This is also incorrect. Estivation refers to a state of dormancy during hot conditions, not cold.
- **Option C: Increased tendency to shiver** - While shivering can generate heat, it is not a primary adaptation for cold climates.
- **Option D: Reduced surface area to volume ratio** - This is correct. A reduced surface area to volume ratio minimizes heat loss, helping animals retain body heat.

4. **Conclusion**: The most important adaptation of animals to cold climates from the given options is **Option D: Reduced surface area to volume ratio**.

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