During the period of a plant's life, the plant is taking in carbon dioxide through photosynthesis, which is how the plant makes energy and grows.Animals eat plants, and some eat other animals in the food chain.You can work out that after about 50 000 years of time, all the radiocarbon will have gone.Therefore, radiocarbon dating is not able to date anything older than 60 or 70 000 years old.
Willard Libby, the principal scientist, had worked in the team making the nuclear bomb during World War 2, so he was an expert in nuclear and atomic chemistry.
Libby later received the Nobel Prize in Chemistry in 1960 for the radiocarbon discovery.
Today, there are over 130 radiocarbon dating laboratories around the world producing radiocarbon dates for the scientific community.
Carbon follows this pathway through the food chain on Earth so that all living things are using carbon, building their bodies until they die.
A tiny part of the carbon on the Earth is called Carbon-14 (C14), or radiocarbon.