A new study dates these Indonesian handprints to at least 40,000 years old.

Kinez Riza

Indonesian cave art may be world's oldest

By Ann GibbonsOct. 8, 2014 , 2:30 PM

The world's oldest cave art may not lie in Europe but rather halfway around the globe in Indonesia, according to a new study of the long-known art. But some archaeologists question the redating of the ancient images.

Thousands of years ago, people on the island of Sulawesi in Indonesia spray-painted stencils of their hands on the walls and roofs of caves by blowing red paint out of their mouths. They also painted strange-looking pigs in red and mulberry hues. Archaeologists assumed the paintings, discovered in the 1950s, were less than 10,000 years old. Now, a team of Australian and Indonesian researchers has found that the paintings are startlingly ancient: The hand stencils are at least 40,000 years old and the animal paintings at least 35,400 years old. That makes them about the same age or even slightly older than the famous cave art in Europe—which was until now the most ancient in the world. The discovery has important implications for how and when humans developed the ability for symbolic expression.

In Africa, where our species was born, people engraved geometric designs on chunks of hematite and ostrich eggshells as early as 78,000 years ago. But the first real sophisticated symbolic art burst on the scene about 35,000 to 40,000 years ago in Europe. At Chauvet Cave in southern France, for example, cave artists covered the walls with rhinos, horses, lions, and women with pronounced vulvas at about this time. Although some archaeologists argued that the human capacity for symbolic expression developed over time in Africa, others felt that the European creative explosion reflected a new leap in human abilities. “What was believed before our study was that Europe was the center of the earliest explosion in human creativity, especially cave art,” says geochemist and archaeologist Maxime Aubert of Griffith University, Gold Coast, in Australia, who led the new study.

Aubert’s colleague Adam Brumm, also of Griffith University, visited the Maros region of southwest Sulawesi in 2011 with Indonesian researchers and wondered if they could date the paintings. They knew that humans had been in the area at least 35,000 years ago, the age given to ocher crayons and ocher-smeared stone tools they had excavated from the Leang Burung 2 rock shelter nearby. They noticed that some of the cave art was covered with “cave popcorn,” small stalactitelike growths that formed atop the paintings when mineral-rich water trickled over the cave walls. Over the next 2 years, Aubert used a diamond saw blade to collect 19 samples of calcite popcorn from 14 paintings in seven caves within a 1-kilometer radius. He then used the concentration of naturally occurring but unstable uranium in the calcite to estimate how much time had passed since the popcorn formed, giving him a minimum age for the art. The method has been proven robust for dating corals and larger rock formations in caves and has recently been adapted to date thin deposits of carbonate on rock art.

The team was surprised to find that the oldest hand stencil dated to at least 39,900 years ago. A painting of a fruit-eating “pig-deer,” called a babirusa, on the ceiling of the same cave dated to at least 35,400 years ago, the team reports online today in Nature. (Watch a video about the research.)

The hand stencils are a bit older than the hand outlines at Chauvet, if the dates are accurate. This suggests either that humans in Europe and Indonesia each invented symbolic art at roughly the same time, or that modern humans brought their artistic capabilities with them as they spread out of Africa starting about 60,000 years ago. The authors prefer the second explanation, because it fits with archaeological evidence showing that humans were not only on Sulawesi at the time, but were also in Australia by at least 50,000 years ago. Some of the Indonesian art resembles paintings in Australia, although much of the Australian rock art is undated.

Others agree that the Indonesian paintings support the African development of symbolic behavior. “The people leaving Africa had the capacity to create images of the world around them,” says paleoanthropologist Alison Brooks of George Washington University in Washington, D.C., who has long held that view.

But everything depends on whether the new dates hold up. “I have a big question mark about the dates,” says paleoanthropologist Randall White of New York University, co-author of a paper published earlier this year in the Bulletin de la Société préhistorique française that challenged the reliability of this dating method. The thin calcite deposits on cave art can be contaminated by new flows of uranium-containing water, dust, or other detritus, making the art seem older than it is, he and his colleagues argued. He thinks the dates need to be verified with a second dating method.

Others, however, say they are satisfied that the team took special measures to date the site. For example, Aubert and his team took 55 samples of the layers of the calcite popcorn, showing that they formed a sort of ministratigraphic sequence in which the layers closest to the art were oldest and the top layers were the youngest. They also tested uranium and thorium contamination at multiple sites. “The work stands as an excellent example of how rigorous choice of samples and rigorous analysis makes the technique sound,” says archaeologist Paul Pettitt of Durham University in the United Kingdom, who was co-author of a paper applying the same method to cave art in Spain.

The team includes Thomas Sutikna of the National Centre for Archaeology in Jakarta and the University of Wollongong in Australia, who helped discover the “hobbit,” a small-statured human species from another Indonesian island, and he and Brumm are already excavating the caves near the newly dated art to search for ocher pieces, stone tools, and bones. Meanwhile, Aubert is optimistic that researchers will find more ancient art. “The discovery must surely be the tip of the iceberg,” Pettitt agrees. “So relatively little fieldwork has been undertaken on sites of this antiquity in the vastness of East Asia that it would be surprising if this were it.”

Neanderthal artists made oldest-known cave paintings

Designs at three Spanish sites are thought to predate human arrival in Europe by at least 20,000 years.

Emma Marris

The ladder-shaped figure on this cave wall in Spain dates back at least 65,000 years.Credit: P. Saura

Neanderthals painted caves in what is now Spain before their cousins, Homo sapiens, even arrived in Europe, according to research published today in Science¹. The finding suggests that the extinct hominids, once assumed to be intellectually inferior to humans, may have been artists with complex beliefs.

Ladder-like shapes, dots and handprints were painted and stenciled deep in caves at three sites in Spain. Their precise meaning may forever be unknowable, says Alistair Pike, an archaeologist at the University of Southampton, UK, who co-authored the study, but they were almost certainly meaningful to our lost kin. “It wasn’t simply decorating your living space,” Pike says. “People were making journeys into the darkness.” 

Humans are thought to have arrived in Europe from Africa around 40,000–45,000 years ago. The three caves in different parts of Spain yielded artworks that are at least 65,000 years old, according to uranium-thorium dating of calcium carbonate that had formed on top of the art.

These mineral deposits develop slowly, as water containing calcium comes into contact with cave surfaces. The water also contains trace levels of uranium from the rock. After the calcium carbonate has precipitated out of the water, a clock of sorts begins to tick, as uranium decays into thorium at a steady, known rate. 

A datação por urânio-tório tem sido usada na geologia há décadas, mas raramente foi empregada para estimar a idade da arte rupestre. Alguns arqueólogos são céticos quanto à abordagem. Eles sugerem que o carbonato de cálcio poderia ter se dissolvido e se cristalizou novamente depois que foi formado - um processo que também poderia ter lavado algum urânio, fazendo com que uma amostra do mineral aparecesse mais velha do que é. Até agora, a mais antiga arte rupestre conhecida era de aproximadamente 40.000 anos

— stenciled hands and animals in an Indonesian site² that was dated in 2014, and discs and hand stencils from a cave in Cantabria, Spain³, that were found by Pike and his colleagues in 2012. 

Drawing conclusions

 

Anticipating objections about its dating method, Pike’s team collected samples from the outer, middle and inner layers of the calcium carbonate crust and dated them separately. As they expected, the inner samples closest to the art yielded the oldest dates, and the outer samples had younger dates because they would have been later layers of precipitate. “We can’t think of any processes that would re-crystalize the calcite and still keep them in stratigraphic order,” Pike says. The researchers waited three years to publish their results after finding their first clearly pre-human date so they could collect multiple examples and publish their methodology. 

Some archaeologists, however, remain unconvinced. “In my opinion, we have to be cautious with these ‘quite old’ results until we have a much larger corpus of dating results,” says Roberto Ontañón Peredo, an archaeologist at the Prehistory and Archaeology Museum of Cantabria in Santander, Spain. “We have to keep a cool head.” 

Pike suggests that such reluctance to believe that Neanderthals were creating cave art may have less to do with methodological disputes than plain old species-ism. “People are very prejudiced against Neanderthals,” he says.

Paola Villa, an archaeologist who studies Neanderthal culture at the University of Colorado Boulder, says that Neanderthals have an undeserved reputation as moronic brutes. She says that since their bodies were “archaic” in the sense of having features of older hominids — such as heavier bones and pronounced brow ridges — everyone assumed they were “behaviourally archaic” as well. “They were stereotyped as knuckle-dragging dimwits,” she says. 

This assumption has fed into theories about their extinction, which have tended to hinge on humans outcompeting slower, dumber Neanderthals. But Villa says a careful review of the research shows “no support for a cognitive gap between Neanderthals and modern humans”. Newer theories instead focus on factors such as low population density and “assimilation by interbreeding” with humans.

The ladder-like art Pike and his colleagues ascribe to Neanderthal artists has, inside its rectangular forms, faint paintings of animals. These remain a mystery, but Pike speculates that they might be the result of “modern humans coming in and adding their own art”. Humans and Neanderthals may have thought alike, interbred and even — in a way — collaborated artistically, he says.