For years, archaeologists thought Europe was the site of the first creative impulses, with famous cave drawings like those at Chauvet, France, putting humans’ innate artistic expression on display. Only in the past decade has that assumption begun to shift, and thanks in large part to the explorations of researchers from the Australian Research Centre for Human Evolution (ARCHE) at Griffith University in Queensland, Australia.
Overturning Eurocentrism
Shortly after completing his Ph.D., Maxime Aubert heard about undated cave art on the Indonesian island of Sulawesi and his curiosity was piqued. Using uranium-series dating, a technique that had not been applied to the paintings before, Aubert — who is now a Professor of archaeological science at Griffith University and researcher both at ARCHE and at the Griffith Centre for Social and Cultural Research — showed that images on the walls and ceilings of the caves had been there for almost 40,000 years, making them at least as ancient as those in Europe, if not even older. The resulting article — published in Nature in 2014 — took the world by storm. Science magazine ranked the research among the top ten discoveries of that year, and noted that it, “could rewrite the history of a key stage in the development of the human mind.” The finding turned the previous theory that human creativity had originated in Europe on its head.
“Essentially they were saying that when humans left Africa they didn’t become collectively modern until they reached Europe — which is not true. We killed that idea,” Aubert says. “It’s more likely that when modern humans left Africa maybe 100,000 years ago they were fully modern.”
A link between past and present
Last year, Aubert applied the same dating approach in the neighboring island of Borneo, studying prehistoric art in a limestone cave in East Kalimantan. He and a group of colleagues found reddish-orange hand stencils and large animal paintings produced between 40,000 and 52,000 years ago. A second phase of paintings of humans, and hand stencils adorned with lines and dots in purple, had been created later, about 20,000 years ago. They include stencils of tiny, childlike hands.
Some of the newer hand stencils were drawn on top of the older ones, suggesting a deliberate relationship between the two phases. The older red hand stencils had been retouched with dots and lines in purple (similar to the younger purple hand stencils), and joined together. “Most of them are painted on the bare wall but if there is super-imposition, they are always painted on top of the red ones,” Aubert explains. “It seems to me that the people 20,000 years ago were aware of the past, the present and the future at the same time.”
Reaching the caves in itself was a major endeavor requiring a flight to the nearest city, a lengthy drive to a local town, paddling by canoe up-river, followed by tramping through the lush Indonesian jungle. Accompanying Aubert were representatives of Indonesia’s National Research Centre for Archaeology (ARKENAS), the Bandung Institute of Technology, and local officials responsible for conservation, along with a team of about 20 people who helped carry tools and supplies.
“We usually go for about a month, so we have a lot of things to carry and we have maybe five or six canoes,” Aubert says. “It’s a big expedition every time.”
Tooth tales
Aubert’s work isn’t the only groundbreaking research to emerge from ARCHE. Griffith University’s Professor Tanya Smith, also a member of the Griffith Centre for Social and Cultural Research, is the author of The Tales Teeth Tell, and has looked at how teeth can reveal what our ancestors ate and even the climate in which they lived.
For two decades, Smith has been studying the fine gradations in the teeth of ancient hominins and great apes, our closest living relatives. The markings disclose the daily rhythms of their owners’ lives, recording the chemistry of what they ate and drank, and when they experienced stress. The degree of precision the analysis offers is remarkable: under a microscope, the fine lines on a tooth register daily increments up until the subject reaches maturity.
By applying new techniques to ancient questions, the researchers at Griffith’s ARCHE are honing our knowledge of human evolution.
Traces of a substance called barium inform researchers about breastfeeding practices, while variations in oxygen levels, called isotopes, shed light on environmental conditions like temperature and precipitation. Since our teeth begin to grow several months before we are born, the first stressful event they record is birth itself.
Recently Smith and her team studied the teeth of Neanderthal children from a site in southern France who were 250,000 years old. In an intimate glimpse of one child’s life, she reported the individual had breastfed for two-and-a-half years, had survived a couple of cold winters and had even ingested lead.
“To put all that information together — to be able to understand something about diet or nursing along with environmental variation and even exposure to a neurotoxicant — was pretty unique,” she says. “Ultimately two-and-a-half years after it was born it stopped nursing during the autumn.”
Agricultural revolution
Information about breastfeeding is important because primates typically care for just one baby at a time. Smith plans to examine changes that may have taken place when early humans abandoned hunting and gathering in favor of agriculturalism. If new modes of food production meant that women were able to spend less time breastfeeding it would help explain the population explosion that occurred.
Still, the transition to agricultural living wasn’t entirely positive because it meant we began to rely on a narrower, more carbohydrate-laden diet. “We see things like cavities becoming more common in agriculturalists,” Smith says. “Skeletal robusticity decreases so we’ve gotten smaller — our jaws have gotten smaller, our faces have gotten smaller. You see tooth impaction becoming more of a problem because you don’t have the big jaws to fit your teeth in.”
The mysteries of our origins won’t be solved any time soon. But by applying new techniques to ancient questions, the researchers at Griffith’s ARCHE are honing our knowledge of human evolution. They’re also enhancing our understanding of the role the Asia-Pacific region played in that story. “We find dozens of [cave paintings sites] in Indonesia every year,” says Maxime Aubert. “It’s amazing.”
