Why are the ideas that earth undergoes change and is billions of years old important for evolutionary theory

The theory that Earth undergoes change is very important to evolutionary theory because then anyone researching evolutionary theory needs to look over what changes the Earth may have went through, and compare and contrast to their research/theory, and  learn from others factual evidence. The theory that the Earth is billions of years old is like the basis of what an evolutionary theory may go off of because they need to know when to start their theory and when to end it.

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