Archeologists use many methods to analyze data from the past. One scientific tool they use is to analyze the radioactive decay of chemical elements found in plant and animal remains, pottery, and even in rocks. Radiocarbon dating, also known as carbon-14 dating, has been one of the most important radioisotope dating methods used. This scientific tool, which was first developed by Willard F. Libby in the late 1940s, has significantly improved the accuracy of assigning dates to past events and artifacts as far back as 70,000 years. It is helping archaeologists, geologists, and anthropologists reconstruct the world’s history by filling in some of the many blank dates in the chronology of the history of our human world and by substantiating and revising other dates.
In 1941, the radioactive atom, carbon-14, was isolated and discovered. Utilizing this discovery of the unstable radioactive isotope of carbon, Libby formulated an idea for using the decay rate of this radioactive form of carbon to date the remains of once-living plants and animals such as charcoal, wood, bone, shells, and fossils. In 1948, while at the University of Chicago, he and his colleagues started experimenting with carbon-14 as a means for dating the past. The scientists proved that carbon-14, which is present in our atmosphere as carbon dioxide, is absorbed by plants, animals, and human beings at a constant rate, and that the amount of carbon-14 is stabilized at a specific amount. A living organism can only intake a finite amount of carbon-14. Then, at the moment the living organism dies, it stops taking in any carbon-14, and the carbon-14 remaining in the organism starts to disintegrate at the half-life rate of 5,568 years (Poole 1961:27). (Today, based on refined calculations/techniques the half-life rate of carbon-14 is generally considered to be 5,730 years) (Wheatley 2004:98; DeYoung 2005:46). From the
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