Sound box of birds is called

Options

A. Pygostyle
B. Larynx
C. Syrinx
D. Synsacrum

Answer

To answer the question "Sound box of birds is called," we will analyze the given options step by step.

### Step-by-Step Solution:

1. **Understanding the Options**:
- The options provided are pegostyle, larynx, syrinx, and synsacrum. We need to identify which of these is specifically the sound box of birds.

2. **Analyzing Option 1: Pegostyle**:
- Pegostyle is described as a triangular plate formed of fused caudal vertebrae that supports tail feathers. This does not relate to sound production in birds.
- **Conclusion**: Pegostyle is not the correct answer.

3. **Analyzing Option 2: Larynx**:
- The larynx is known as the voice box in many animals, including birds. However, it is noted that in birds, the larynx does not function in vocalization like it does in mammals.
- **Conclusion**: While the larynx is present, it is not the primary sound-producing organ in birds.

4. **Analyzing Option 3: Syrinx**:
- The syrinx is specifically identified as the vocal organ of birds. It is located at the base of the trachea and is responsible for sound production through the vibrations of membranes when air flows through it.
- **Conclusion**: Syrinx is the correct answer as it is the sound box of birds.

5. **Analyzing Option 4: Synsacrum**:
- The synsacrum is a fused series of vertebrae found in the pelvic region of birds and dinosaurs. It does not have any role in sound production.
- **Conclusion**: Synsacrum is not related to sound production.

### Final Answer:
The sound box of birds is called the **syrinx**.

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