Problems with cabon dating
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.Yet cave paintings are generally considered to be physical traces of early modern behaviour, because the creation of art requires abstract thought. ‘The reason we started to look at dating cave art was because we had this slight conundrum,’ says Alistair Pike, an archaeologist at the University of Southampton in the UK.‘When we look at genetics, they suggest that modern humans become anatomically modern between 150,000 and 200,000 years ago in Africa.
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.
‘As it formed on top of the painting, it therefore gives you a minimum age of the painting,’ Pike says.
This isn’t ideal, but it’s currently the best tool.
‘We’ve got dates that are tantalisingly close to the point at which modern humans arrived,’ explains Pike. hand stencils to see whether or not dates come out in the period where we know there were only Neanderthals in northern Spain.’The issue of Neanderthal art regularly appears in the media, but is controversial in the academic world.
For some, it fits in with emerging evidence that Neanderthals were an intelligent human species, but others remain unconvinced.
well, us.‘The great breakthrough in Quaternary archaeology was radiocarbon dating,’ Walker says.