Carbon dating false
Organisms capture a certain amount of carbon-14 from the atmosphere when they are alive.
By measuring the ratio of the radio isotope to non-radioactive carbon, the amount of carbon-14 decay can be worked out, thereby giving an age for the specimen in question.
One particularly interesting theory shows that the majority of the world has a single large land mass.
When a huge shelf of water 10 miles beneath the earth was released, the very shape of the earth was changed.
Plates moved across the planet, forming the continents and oceans as we see them today.
The clock was initially calibrated by dating objects of known age such as Egyptian mummies and bread from Pompeii; work that won Willard Libby the 1960 Nobel Prize in Chemistry.
But even he “realized that there probably would be variation”, says Christopher Bronk Ramsey, a geochronologist at the University of Oxford, UK, who led the latest work, published today in Science.