The world’s oldest artwork, believed to be at least 40,800 years old, was discovered in the Cave of El Castillo, literally, “the cave of castles”, near the town of Puente Viesgo, about 30 kilometers south of Santander in the Cantabria region of what is today Spain. The cave and its artwork was discovered more than a century ago but the paintings couldn’t be properly dated using traditional methods such as radiocarbon dating because of the absence of organic pigment. A couple of years ago, a team of archeologists dated the thin layer of calcite formations that developed on top of the art using radioactive decay of uranium and arrived at an astounding figure of 40,800 years, making it the earliest known example of prehistoric art.
The caves of El Castillo contain more than 100 different images painted in charcoal and red ochre on the walls and ceilings of multiple chambers. There are pictures and outlines of animals and club-shaped figures but most are simple hand stencils and red disks created by placing hands on the wall surface and blowing paint on top of it. But are those human hands?
Archaeologists from England and Spain used the uranium-thorium technique to date 50 paintings and engravings from 11 cave sites in Asturias and Cantabria. They did this by collecting samples of the thin crusts of calcium carbonate that formed atop the images through the same process that forms stalactites and stalagmites. The crusts incorporate small amounts of uranium, which decays into thorium over time. By analyzing the amount of thorium in a sample using a mass spectrometer, the researchers could determine how much time had passed since the crusts formed, thereby providing a minimum age for the images underneath.
The paintings, over which the calcite layer formed, has to be obviously older than the first layer, perhaps, by even thousands of years.
Modern humans arrived in Europe from Africa some 41,500 years ago. And before 42,000 years ago, the only humans in Europe were Neanderthals, who had been running around Europe for 200,000 or 300,000 years. Alistair Pike, an archaeologist at the University of Bristol in England, who developed the technique to date the paintings, argue that either modern humans arrived with painting already part of their cultural activity or it developed very shortly after. Another possibility is that the paintings weren’t made by humans at all, but by Neanderthals.
Many scientists had long doubted whether Neanderthals were capable of producing symbolic art. But that view begun to change in recent years with the discovery of several evidences of Neanderthal’s sophistication such as jewelry, tiny art objects and pigments for possibly body painting. If they were decorating their bodies with symbols, many experts say, they almost certainly had language and the capacity for symbolic thinking.
It does however surprise archaeologists like Pat Shipman, who has spent a lifetime studying symbolic behavior. She wonders why Neanderthals waited until about the time humans arrived to get the itch to paint.
"OK, Neanderthals had been there for 300,000 years, and they're not doing this," Shipman says. "If they are not doing it before, why would they suddenly start doing it at that point?"
Shipman notes that long before humans made the trek from Africa to Europe, they had been making all sorts of symbolic artifacts — ocher hash marks on stone or symmetrical marks on ostrich eggs.
"I find it easiest to assume that people who are already doing that moved into more figurative representations than thinking that an entirely other species of people suddenly came up with making figurative art," Shipman says
The researchers are currently looking at additional sites in western Europe to see if they can get dates older than 42,000 years ago.
Entrance to the cave of El Castillo.