A
scientific technique for
estimating the age of very old
objects. It is based on the principle that all living organisms exchange
carbon with their surroundings. They intake sugars and starches as food, and exhale
carbon dioxide. The concentration of the
isotope of carbon,
carbon-14, should be exactly the same in a living
organism as the concentration in its surroundings. As soon as an organism dies, it ceases to exchange carbon with its surroundings. The
radioactive carbon-14, which has a half life of over 5000 years, slowly decays. The age of an artifact can therefore be estimated by comparing the
proportion of carbon-14 its body contains, as opposed to the proportion currently living organisms contain.
This method does have flaws. For example, if the proportion of Carbon-14 was ever much higher or much lower, for whatever reason, this would skew the results. Also,
researchers have fed
mice diets which contained only
carbon-12, so when the mice died and were carbon dated, their ages were estimated at several thousand years.