Danish Stone Age pots may not be as old as originally determined if fish were cooked in them.
A physicist from Aarhus University found that there may be an error of up to 2,000 years in dating by Carbon-14 in areas where fish cookery was prevalent, "due to the fact that fish contain less of the radioactive substance Carbon 14 if they have lived in hard water."
Archaeologists experimented by preparing a clay vessel similar to Stone Age ones, prepared a fish dish in it, and made sure that some fish stuck to the pot. Then, they dated it using Carbon-14. The result showed that the modern replica was 700 years old. "There’s probably no need to rewrite the history books, but it’s likely that they contain some incorrectly dated excavation sites, Associate Professor Felix Riede told Aarhus University’s newsletter Rømer."