Radiocarbon dating, invented in the late 1940s and since then improved to provide
This method measures the decomposition of carbon-14,unstable isotope of carbon, which is formed in all organic substances under the influence of cosmic radiation. However, this radiation is not always constant - in order to take into account its fluctuations in the Earth’s atmosphere, scientists began to measure radiocarbon with calibration on a tree. The method consists in measuring the content of the isotope in a tree whose age is known from the annual rings, and then comparing these values with the test sample.
Since 1986, scientists have used a single wood calibration scale for all artifacts in the Northern Hemisphere, including those in Europe and the Mediterranean.
In the new work, researchers put underthe accuracy of one calibration curve for the entire Northern Hemisphere is questionable. They compared radiocarbon dates from northern Europe (Germany) and from the Mediterranean (central Turkey) in the second and first millennia BC. The analysis showed that there are small differences in carbon concentrations between these regions, which can have a significant impact on the accuracy of dating certain artifacts.
These differences can potentially affectcalendar dates of the prehistoric period for up to several decades, conclude the authors of the work. The adjustment of dates, in particular, can relate to the dates of death and burial of the Egyptian pharaoh Tutankhamun, which date from about 1320-1310 years BC.
Previously in Iranfoundthe oldest petroglyph depicting a praying mantis. This is an extremely rare case when an invertebrate animal is depicted in rock art.