Problems with cabon dating
Instead, Pike’s team turned to uranium-series dating, another radiometric method.Uranium-238 decays through a series of isotopes to uranium-234, which then itself decays to thorium-230.It’s possible to measure the ratios of uranium-238/uranium-234 and thorium-230/uranium-238, the latter of which depends on the former.Since only uranium, and not thorium, is present at sample formation, comparing the two ratios can be used to calculate the time passed since the sample formed. Pike’s team are not actually dating the painting itself, but small calcite growths on top of it.Regardless, if there is evidence to find that Neanderthals were artists, dating will be the thing to expose it.According to Walker, the importance of this type of dating can’t be overestimated.A portion of the carbon is the radioactive isotope carbon-14.
‘When we look at genetics, they suggest that modern humans become anatomically modern between 150,000 and 200,000 years ago in Africa.
A huge development in the story of humans is ‘modern’ behaviour, or acting like a human as opposed to acting like a two-legged ape – but it’s hard to date.
For example, it’s difficult to say exactly when people started to think abstract thoughts or speak to communicate.
[but] if you haven’t got organic pigment in there, you can’t use radiocarbon and you’d be destroying the art, which is very valuable.
To take a normal radiocarbon sample would be unduly disruptive,’ he explains.