One of these is primary ectotherm

Options

A. Lizard
B. Hawk
C. Shrew
D. Elephant

Answer

**Step-by-Step Solution:**

1. **Understanding Ectotherms**: Ectotherms are animals that cannot internally regulate their body temperature. Instead, their body temperature varies with the external environment. They are often referred to as "cold-blooded" animals.

2. **Identifying Ectothermic Animals**: Common examples of ectotherms include amphibians, fishes, and reptiles. These animals adjust their body temperature based on the temperature of their surroundings.

3. **Differentiating Between Ectotherms and Endotherms**: Endotherms, on the other hand, are animals that maintain a constant body temperature regardless of the external environment. This group includes birds (Aves) and mammals.

4. **Analyzing the Options**: The question provides four options. We need to identify which of these is a primary ectotherm.
- **Lizard**: A reptile, which is an ectotherm.
- **Hawk**: A bird (Aves), which is an endotherm.
- **Shrew**: A mammal, which is an endotherm.
- **Elephant**: A mammal, which is also an endotherm.

5. **Conclusion**: Among the given options, the only primary ectotherm is the Lizard.

**Final Answer**: The primary ectotherm is the Lizard.

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