The practice of cave art in Europe thus began up to 10,000 years earlier than previously thought, indicating the paintings were created either by the first anatomically modern humans in Europe or, perhaps, by Neanderthals.
Fifty paintings in 11 caves in Northern Spain, including the UNESCO World Heritage sites of Altamira, El Castillo and Tito Bustillo, were dated by a team of UK, Spanish and Portuguese researchers led by Dr Alistair Pike of the University of Bristol, UK.
As traditional methods such as radiocarbon dating don't work where there is no organic pigment, the team dated the formation of tiny stalactites on top of the paintings using the radioactive decay of uranium. This gave a minimum age for the art. Where larger stalagmites had been painted, maximum ages were also obtained.
Hand stencils and disks made by blowing paint onto the wall in El Castillo cave were found to date back to at least 40,800 years, making them the oldest known cave art in Europe, 5-10,000 years older than previous examples from France.