Birds differ from reptiles in

Options

A. Being endothermic
B. Being ectothermic
C. both
D. Being viviparous

Answer

To solve the question "Birds differ from reptiles in," we will analyze the key characteristics that distinguish birds from reptiles.

**Step 1: Identify the main differences between birds and reptiles.**
- Birds and reptiles are both part of the animal kingdom but belong to different classes. The primary difference lies in their body temperature regulation.

**Step 2: Understand the concept of body temperature regulation.**
- Birds are classified as endothermic animals, which means they are warm-blooded. This allows them to maintain a constant body temperature regardless of the external environment.

**Step 3: Compare with reptiles.**
- Reptiles, on the other hand, are classified as ectothermic or exothermic animals, meaning they are cold-blooded. Their body temperature is dependent on the surrounding environment, and they cannot internally regulate their body temperature.

**Step 4: Clarify the reproductive aspect.**
- Both birds and reptiles are oviparous, meaning they lay eggs. Therefore, this characteristic does not differentiate them.

**Step 5: Conclude the main difference.**
- The main difference between birds and reptiles is that birds are endothermic (warm-blooded), while reptiles are ectothermic (cold-blooded).

**Final Answer: Birds differ from reptiles in being endothermic.**

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