Law of Superposition and Radioactive Decay

People know how old they are because the law of superposition shows that the layer we were found different mammals were found and one was the saber tooth

The saber tooth tiger lived  about 2.5 million ago to 10,000 years ago and it appeared in the early Tertiary era.

This dot shows how many carbon 14 particles are in the earliest saber tooth fossil foundation

Carbon 14 dating shows how old things are by showing how many carbon 14 particles are in the fossil