The radiocarbon method was developed by a team of scientists led by the late Professor Willard F.Libby of the University of Chicago after the end of World War 2.The half-life refers to the amount of time it takes for half the radiocarbon in a sample of bone or shell or any carbon sample to disappear.
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.
After twice that time (about 11000 years), another half of that remaining amount will have disappeared.
After another 5568 years, again another half will have disappeared.
After the war he became very interested in peaceful applications of atomic science.