What five animals that have hard skin?

Here are five animals that have hard skin, with explanations for why:

1. Armadillos: These mammals have bony plates embedded in their skin, forming a protective shell.

2. Crocodiles: Crocodiles have thick, leathery skin covered in scales, which provides armor and protection against predators.

3. Turtles: Turtles have a bony shell that forms from their ribs and vertebrae, completely encasing their bodies.

4. Snakes: While not entirely hard, snake skin is covered in scales, providing protection and allowing them to move easily.

5. Tortoises: Like turtles, tortoises have a hard shell for protection. They are terrestrial turtles, living mainly on land.

Let me know if you want to learn more about any of these animals!