In the barren inland desert of Patagonia, Argentina, there is a remote cave decorated with some 900 paintings of people, animals and abstract designs. Until recently, archaeologists assumed that the rock art at this site, known as Cueva Huenul 1, was created within the last few thousand years.
But in a paper published Wednesday in the journal Science Advances, archaeologists say one of the cave's most mysterious motifs, a comb-like pattern, first appeared about 8,200 years ago, making it by far the oldest example of rock art. A place on Earth where our species will settle. Cave artists continued to draw the same comb designs in black pigment for thousands of years, an era when there was virtually no other human activity at the site. Cave art provides a rare glimpse into a culture that may have relied on these designs to pass on valuable insights across generations during a period of climate change.
“We got the results and we were very surprised,” said Guadalupe Romero Villanueva, an archaeologist at the Argentine government agency CONICET and the National Institute of Anthropology and Latin American Thought in Buenos Aires and author of the study. “It was a shock and we had to rethink some things.”
Patagonia, located on the southern tip of South America, was not reached by humans until about 12,000 years ago. These early inhabitants thrived in Cueva Huenul 1 for generations, leaving traces of their habitation.
Then, about 10,000 years ago, climate changes made the region drier and more hostile. The archaeological record in the cave likewise dried up over the next few thousand years, suggesting that the site was largely abandoned due to environmental pressures.
According to Dr. Romero Villanueva and his colleagues, who used radiocarbon dating to determine the age of the painting, the comb motif overlaps with this long period of suffering. The team also found that the black paint was probably made from charred wood, such as burnt shrubs or cacti.
“As interesting as the period is, for us it is more important that these paintings contain basically the same theme for almost 3,000 years,” said Ramiro Barberena, an archaeologist at CONICET and author of the study. Catholic University of Temuco, Argentina and Catholic University of Temuco, Chile.
He added that this was evidence “of the continuity of information transmission in a very small and mobile society.”
Although the meaning of the comb motif was lost over time, researchers speculate that the comb may have helped preserve the collective memory and oral traditions of the people who endured unusually hot and dry times.
Relationships between ancient human groups that developed and shared such rock art may have increased their chances of survival in this difficult environment, Dr Barberena said.
Andrés Troncoso, an archaeologist in the Department of Anthropology at the University of Chile who was not involved in the study, said he agreed with that interpretation. “This paper provides a contribution to the debate about how humans have coped with climate change in the past,” he said.
Although the purpose of the comb motif will likely remain a mystery, the motif's continued presence in the cave opens a new window into Patagonia's prehistoric peoples.
“I can’t help but think about these people,” said Dr. Romero Villanueva. “They were in the same place and admiring the same scenery. People who live here, maybe families, gather here for the social aspect. “It’s really emotional for us.”