Which one is not a specific trait of birds?

Options

A. Bipedal locomotion
B. Toothless beak
C. Wings
D. Feathers

Answer

To determine which trait is not specific to birds, let's analyze each option step by step.

### Step 1: Understanding Bipedal Locomotion
- Bipedal locomotion refers to the ability to walk or run using only two legs.
- This trait is not exclusive to birds; it is also found in some mammals (like humans) and other animals.

### Step 2: Analyzing the Toothless Beak
- Birds possess a beak that does not have teeth.
- Instead of chewing, birds use their gizzard to grind food, which is a specific adaptation of birds.

### Step 3: Examining Wings
- Wings are a defining characteristic of birds, allowing them to fly.
- This adaptation is unique to birds among vertebrates, making it a specific trait.

### Step 4: Considering Feathers
- Feathers are another unique feature of birds, providing insulation and aiding in flight.
- Like wings, feathers are a specific trait of birds.

### Conclusion
- Among the options provided, bipedal locomotion is not a specific trait of birds, as it is also found in other animals, particularly mammals.
- Therefore, the correct answer is **bipedal locomotion**.

### Final Answer
**Bipedal locomotion is not a specific trait of birds.**

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