One half-life is the amount of time required for of the original atoms in a sample to decay.Over the second half-life, of the atoms remaining decay, which leaves of the original quantity, and so on.New research shows, however, that some estimates based on carbon may have erred by thousands of years.It is too soon to know whether the discovery will seriously upset the estimated dates of events like the arrival of human beings in the Western Hemisphere, scientists said.This technique is not restricted to bones; it can also be used on cloth, wood and plant fibers.Carbon-14 dating has been used successfully on the Dead Sea Scrolls, Minoan ruins and tombs of the pharaohs among other things. The half-life of carbon-14 is approximately 5,730 years. dinosaurs the evolution alleges lived millions of years ago.The age of the carbon in the rock is different from that of the carbon in the air and makes carbon dating data for those organisms inaccurate under the assumptions normally used for carbon dating.This restriction extends to animals that consume seafood in their diet.
Following death, however, no new carbon is consumed.
Carbon-14 cannot be used to date biological artifacts of organisms that did not get their carbon dioxide from the air.
This rules out carbon dating for most aquatic organisms, because they often obtain at least some of their carbon from dissolved carbonate rock.
In some cases, the latter ratio appears to be a much more accurate gauge of age than the customary method of carbon dating, the scientists said.
In principle, any material of plant or animal origin, including textiles, wood, bones and leather, can be dated by its content of carbon 14, a radioactive form of carbon in the environment that is incorporated by all living things.