When reptiles come down which animals took over the earth?

Options

A. Birds
B. Dinosaurs
C. Mammals
D. Amphibians

Answer

**Step-by-Step Text Solution:**

1. **Understanding Reptiles**: Reptiles are vertebrate animals characterized by having a backbone, at least one lung, being cold-blooded, laying eggs, and having bodies covered with scales.

2. **Reptiles' Evolution**: When reptiles began to decline, some adapted to aquatic environments and evolved into fish-like reptiles, while others transitioned to land and evolved into dinosaurs.

3. **Extinction of Dinosaurs**: Dinosaurs dominated the Earth for a significant period. However, they faced a mass extinction event, likely caused by a comet impact, which led to their disappearance.

4. **Rise of Mammals**: Following the extinction of dinosaurs, mammals began to thrive. They reproduced at an increased rate and underwent diversification, leading to the emergence of various species.

5. **Survival of Early Mammals**: The first mammals that survived the extinction event were small creatures resembling modern shrews. They existed around 160 million years ago during the Jurassic era.

6. **Conclusion**: Therefore, when reptiles (specifically dinosaurs) went extinct, mammals took over the Earth, leading to the evolution of modern mammals from their early ancestors.

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