The eyes of birds are peculiar due to the presence of

Options

A. large pupil
B. large number of cones
C. pecten
D. sensitive retina

Answer

**Step-by-Step Solution:**

1. **Understanding Bird Anatomy**: Birds belong to the class Aves and are characterized by various adaptations that facilitate flight and enhance their sensory capabilities, particularly vision.

2. **Identifying Eye Features**: The question asks about the peculiar features of bird eyes. We need to evaluate the options provided to determine which one is unique to birds.

3. **Evaluating Options**:
- **Large Pupil**: Birds do not have large pupils; their pupil size is similar to that of mammals. Thus, this option is incorrect.
- **Large Number of Cones**: Birds do not have a significantly larger number of cones compared to other vertebrates. Therefore, this option is also incorrect.
- **Pecten**: This is a unique structure found in the eyes of birds, located near the retina. The pecten is responsible for providing nourishment to the retina and is a distinctive feature of avian eyes.
- **Sensitive Retina**: While birds do have a sensitive retina, this is not a unique characteristic, as all vertebrates possess this trait. Hence, this option is incorrect.

4. **Conclusion**: The peculiar feature of bird eyes is the presence of the pecten, which is not found in other vertebrates.

**Final Answer**: The eyes of birds are peculiar due to the presence of **pecten**.

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