Tail vertebrae of birds form

Options

A. Wish bone
B. Chevron bone
C. Urostyle
D. Pygostyle.

Answer

**Step-by-Step Solution:**

1. **Understanding the Vertebral Column in Birds**: The vertebral column of birds is divided into several regions, similar to that of humans. These regions include cervical, thoracic, lumbar, and coccygeal vertebrae.

2. **Identifying the Tail Region**: In birds, the tail region is specifically formed by the coccygeal vertebrae, which are located at the caudal (tail) end of the vertebral column.

3. **Fusion of Coccygeal Vertebrae**: The coccygeal vertebrae in birds fuse together to form a single structure. This fusion is important for providing stability and support to the tail.

4. **Naming the Structure**: The fused coccygeal vertebrae create a bone known as the **pygostyle**. This structure is unique to birds and plays a crucial role in supporting the tail feathers.

5. **Characteristics of the Pygostyle**: The pygostyle is a flat, plate-like structure that serves as an anchor for the tail feathers. It also contains musculature that aids in the movement and positioning of the tail.

6. **Conclusion**: Therefore, the tail vertebrae of birds form the **pygostyle**, which is essential for tail feather support and bird locomotion.

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