Researchers investigating thin layers of limestone deposited on ancient cave paintings suggest in a paper published in Science last week two intriguing possibilities: the famous cave paintings in France and Spain may be as much as 15,000 years older than previously established; Neanderthals may have been cave painters as well as were the anatomically modern humans who replaced them.
A team led by Alistair Pike of the University of Bristol in the United Kingdom sought to confirm previously assigned dates or establish new dates for cave paintings by applying uranium series analysis of calcium carbonate deposits overlaying or underlaying paints applied to cave walls. Pike and his associates dated paintings in the El Castillo cave in northern Spain, near the famous site of Altamira, to 40,500 years ago. The most famous cave paintings, located at Lascaux in France and Altamira were previously dated to around 25,000 years ago using carbon-14 dating technology. The caves investigated by Pike and his team contain no organic material and thus cannot be dated by carbon-14. U-series dating of the calcium carbonate layers in the Spanish caves investigated by Pike is the only viable method at present. The new and the old dates fall on either side of the accepted date of 28 to 30,000 years ago for Neanderthal extinction.
Since the dates established by carbon-14 for the paintings at Lascaux and Altamira occurred after the the remnant Neanderthals became extinct, it follows the cave paintings were created by our Homo sapiens ancestors. If, on the other hand, the earlier dates of 38,000 to 40,000 years determined by Pike and his team are accepted the Neanderthals could have been the cave painters. It is believed the first anatomically modern humans from Africa entered Europe and encountered resident Neanderthal populations around 45,000 years ago.
The uranium series dates for the layers of calcium carbonate associated with the paints however are problematical, as discussed by the authors in their paper. These U-series dates are not as well founded or reliable as the previous carbon-14 dates found for Lascaux and Altamira. Therefore the possibility the paintings may be of Neanderthal origin is a tentative hypothesis. Read the full article in Science.
The cave paintings were achieved by carrying a particular coloring in the mouth and applying it to the cave wall by spitting the coloring through a hollow reed or other material similar to a modern straw. In some of these caves the same calcium carbonate seeping through the cave ceiling and forming stalactites and stalagmites, overlay ancient paintings and another cases the painting was done directly on a previous deposit of calcium carbonate. Found frequently in these paintings is the outline of the human hand, in effect stenciled on the cave wall.