Previously, the scientists dated the cave paintings by carbon-dating small samples of cave "popcorn" — calcite clusters that have accumulated over thousands of years.

But in the new study, Brumm and his team used even smaller calcite samples — just 0.002 inches (44 microns) long. By taking much smaller samples, the archaeologists gain a higher resolution of the age distribution of the calcite on the cave walls. The technique also minimizes the damage made to the artwork.

"It really changes the way we do the dating on record, and it can be applied to other records as well," study co-author Renaud Joannes-Boyau, a geochronologist at Southern Cross University in Australia, said at the news conference.