Birds and mammals in geological development of earth arose in period

Options

A. Permain
B. Carboniferous
C. Jurassic
D. Oligocene and Ecoene.

Answer

To answer the question regarding the geological period in which birds and mammals arose, we can analyze the provided options step by step.

### Step-by-Step Solution:

1. **Understanding the Geological Periods**: We need to evaluate the four options given: Permian, Carboniferous, Jurassic, and Oligocene/Eocene.

2. **Evaluating the Permian Period**:
- The Permian period occurred around 299 million years ago.
- It is known for the mass extinction of species and the emergence of the supercontinent Pangaea.
- There was no significant development of birds and mammals during this period.
- **Conclusion**: The Permian period is **not** the correct answer.

3. **Evaluating the Carboniferous Period**:
- The Carboniferous period is also known as the Paleozoic era.
- It was characterized by the presence of large swamps and coal formation.
- Despite its significance, birds and mammals did not evolve during this period.
- **Conclusion**: The Carboniferous period is **not** the correct answer.

4. **Evaluating the Jurassic Period**:
- The Jurassic period is part of the Mesozoic era.
- It is known for a warm climate that supported lush vegetation and abundant life, including dinosaurs.
- This period also saw the emergence of both birds and mammals.
- **Conclusion**: The Jurassic period is **the correct answer**.

5. **Evaluating the Oligocene and Eocene Periods**:
- These periods are known for significant transitions and mass extinctions, particularly of aquatic species.
- There was no notable emergence of birds and mammals during these periods.
- **Conclusion**: The Oligocene and Eocene periods are **not** the correct answer.

### Final Answer:
The correct geological period in which birds and mammals arose is the **Jurassic period**.

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