Because it reacts identically to C-12 and C-13, C-14 becomes attached to complex organic molecules through photosynthesis in plants and becomes part of their molecular makeup.Animals eating those plants in turn absorb Carbon-14 as well as the stable isotopes. The Radiocarbon Revolution Since its development by Willard Libby in the 1940s, radiocarbon (14C) dating has become one of the most essential tools in archaeology.Radiocarbon dating was the first chronometric technique widely available to archaeologists and was especially useful because it allowed researchers to directly date the panoply of organic remains often found in archaeological sites including artifacts made from bone, shell, wood, and other carbon based materials.It is naturally unstable and so it will spontaneously decay back into N-14 after a period of time.It takes about 5,730 years for half of a sample of radiocarbon to decay back into nitrogen.
This calendar, with the months January through December, is a business standard used in many places round the world to define the year: one which hearkens back to Christian and Roman Imperial precedents.
This process of ingesting C-14 continues as long as the plant or animal remains alive.
The C-14 within an organism is continually decaying into stable carbon isotopes, but since the organism is absorbing more C-14 during its life, the ratio of C-14 to C-12 remains about the same as the ratio in the atmosphere.
C-14 is produced in the upper atmosphere when nitrogen-14 (N-14) is altered through the effects of cosmic radiation bombardment (a proton is displaced by a neutron effectively changing the nitrogen atom into a carbon isotope).
The new isotope is called "radiocarbon" because it is radioactive, though it is not dangerous.