Why are frogs said to have two life's

Frogs are said to have two lives because when they hatch, they turn into little fish-like creatures known as pollywogs that live underwater. This is considered their first life. Then, the pollywogs mature into tadpoles and start budding limbs. Finally, after a while in this stage, their arms and legs will become fully developed, making them frogs and they will leave the water to live the rest of their life without needing water as their primary environment. This is considered their second life.
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