Carbon dating zooarchaeology
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.
Libby in 1949, and has become an indispensable part of the archaeologist's tool kit since.These various chronologies and their inherent inconsistencies, known as ‘relative dates,’ are a constant series of hurdles in the quest of historians and archaeologists to record mankind’s existence on earth.However, in the 1940s, the organization of time was transformed by the revelation of radiometric dating and the subsequent creation of a scientific chronology of humankind, known as ‘absolute dating’.For periods without a historic record, attempts have been made to categorize tool kits, pottery styles, and architectural forms into regional timelines.Some ill-fated attempts to define time even attempted to count backwards through the genealogies of the Bible, establishing a series of dates which remain a cause of confusion.Plants and animals naturally incorporate both the abundant C-12 isotope and the much rarer radiocarbon isotope into their tissues in about the same proportions as the two occur in the atmosphere during their lifetimes.
When a creature dies, it ceases to consume more radiocarbon while the C-14 already in its body continues to decay back into nitrogen.
In contrast to relative dating techniques whereby artifacts were simply designated as "older" or "younger" than other cultural remains based on the presence of fossils or stratigraphic position, 14C dating provided an easy and increasingly accessible way for archaeologists to construct chronologies of human behavior and examine temporal changes through time at a finer scale than what had previously been possible.
The application of Accelerator Mass Spectrometry (AMS) for radiocarbon dating in the late 1970s was also a major achievement.
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.
Radiocarbon dating is especially good for determining the age of sites occupied within the last 26,000 years or so (but has the potential for sites over 50,000), can be used on carbon-based materials (organic or inorganic), and can be accurate to within ±30-50 years.