Enlist three peculiar features of mammalian ear.

Explanation

### Step-by-Step Solution:

1. **Identify the Structure of the Mammalian Ear**:
- The mammalian ear is divided into three main parts: the outer ear, the middle ear, and the inner ear. Each part has distinct features that contribute to hearing.

2. **Feature 1: Presence of Pinna (Auricle)**:
- The pinna, also known as the auricle, is the visible part of the outer ear. Its primary function is to collect sound waves from the environment and direct them into the ear canal. This structure is unique to mammals and plays a crucial role in sound localization.

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