Which of the following were abundant in mesozoic era
Or
Birds are evolved from

Options

A. Pisces
B. mammals
C. birds
D. reptiles

Answer

**Step-by-Step Solution:**

1. **Understanding the Mesozoic Era**: The Mesozoic Era is known as the "Age of Reptiles" and lasted from about 252 to 66 million years ago. During this time, reptiles, including dinosaurs, were the dominant terrestrial vertebrates.

2. **Identifying the Abundant Groups**: The question asks which groups were abundant during the Mesozoic Era. The options provided are:
- A) Fishes
- B) Mammals
- C) Birds
- D) Reptiles

3. **Analyzing Each Option**:
- **Fishes**: While fishes existed during the Mesozoic, they were not the dominant group of that era.
- **Mammals**: Mammals began to appear in the late Mesozoic but were not abundant until the Cenozoic Era.
- **Birds**: Birds evolved during the Mesozoic Era, specifically from theropod dinosaurs, but they were not the most abundant group.
- **Reptiles**: Reptiles, particularly dinosaurs, were indeed the most abundant and diverse group during the Mesozoic Era.

4. **Conclusion**: Based on the analysis, the correct answer to the question of which group was abundant in the Mesozoic Era is **Reptiles** (Option D).

5. **Bird Evolution**: The question also asks about the evolution of birds. Birds are believed to have evolved from a group of theropod dinosaurs during the Jurassic period of the Mesozoic Era.

**Final Answer**: D) Reptiles were abundant in the Mesozoic Era, and birds evolved from reptiles.

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