Radiocarbon Dating 

Radiocarbon dating is based on the fact that all plants take in a certain amount of Carbon14 when they utilize carbon dioxide (CO_{2}) for photosynthesis. Since Carbon14 is a radioactive isotope of Carbon (Carbon12), it decays until 50% of its original material is left, and it becomes Nitrogen14. This decay rate is known as the halflife, which was calculated by scientists to be approximately 5730 years for Carbon14. If the original amount of Carbon14 in a specimen of organic material is , known, then its age can be determined by measuring the amount of Carbon14 left. For example, if 50% of the Carbon14 remains in a piece of burned wood (charcoal) then that piece of wood is 5730 years old. Radiocarbon dating is gaining further usefulness due to the fact that it can now date a wider range of materials and do it using smaller amounts of them. 