Colossal petroglyphs could be ancient boundaries, research suggests

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news about fascinating discoveries, scientific developments and more.

Ancient petroglyphs in what is now South America – believed to be among the largest in the world – were intended to mark the boundaries of the areas inhabited by their creators, according to a new study.

Birds, Amazonian centipedes, human figures and geometric shapes are among the designs, found at 14 sites – most already known, but some newly discovered – along a 60-mile stretch of the Orinoco River, in present-day Venezuela and Colombia .

The most common motif, however, is giant snakes, and one in particular – at a site called Cerro Pintado in Venezuela – measuring around 42 meters in length is probably the largest rock engraving recorded anywhere in the world, the researchers suggested. .

“There are two sides to the fact that these are territorial markers,” said Dr. Philip Riris, lead author of the study published Monday in the journal Antiquity. “You could be a warning sign: you’re in our backyard, you better behave. The other could be an identity marker: you’re in our backyard, you’re among friends. But I don’t think they had a single goal, so they could easily have been both.”

The mythology of the snake

The study focuses on the meaning and role the snakes play in the mythology of the area’s indigenous people, says Riris, a senior lecturer in archaeological environmental modeling at Bournemouth University in the United Kingdom. He thinks local residents probably carved the rocks between 1,000 and 2,000 years ago, based on pottery and motifs from that era found in the same area.

“Snakes are very interesting because they are both creators and protectors. According to local mythology, they formed the rivers as they traveled, but they are also predators, full of dangerous energies that you must respect so as not to fall prey to their wrath,” said Riris, explaining why they also have a double meaning as petroglyphs.

All snake designs share a visual consistency, and Riris believes they could represent boa constrictors or anacondas, although the artists were not necessarily interested in accurately depicting particular species: “Native people do not always distinguish species in the same way as we do in the scientific taxonomy – they could just be large, predatory snakes that kill by constricting,” he said.

Human figures are often depicted alongside the snakes, as well as giant Amazon centipedes, which are predatory on snakes in the Orinoco. The geometric designs include concentric circles, spirals and rectangles, but their meaning is not entirely clear, according to Riris.

The use of such ancient monumental markers as territorial markers has been observed before, but the Orinoco carvings stand out, Riris noted.

“What makes the Orinoco special is how big they are, the sheer quantity and density, and how far their makers had to go to make them,” he said. Some of the rock formations on which they are carved are “dangerous,” Riris added, noting that the artists may have had to use ropes or ladders to reach them.

The monumental petroglyphs of a snake's tail in Colombia dwarf the people in this image.  -Philip Riris et al.

The monumental petroglyphs of a snake’s tail in Colombia dwarf the people in this image. -Philip Riris et al.

Native custodians

The study is the result of data collected during ten years of fieldwork by Riris and his colleagues – co-authors Dr. José Oliver and Natalia Lozada Mendieta – although some of the research was used for other studies. Oliver is a reader in Latin American archeology at University College London and Lozada Mendieta is an assistant professor of art history at the Universidad de Los Andes in Colombia.

The markers are located in a section of the river called the Atures Rapids, which is known to have been an important trade and travel route in prehistoric times. The team used special software to recreate the ancient residents’ point of view and visualize what the markings would have looked like to them.

Today, with tourism rapidly increasing, the sites are at risk of vandalism, and the researchers have registered them with the Colombian and Venezuelan national heritage institutions.

“Fortunately, as far as we know, none of them have been damaged, but with more people around they are more vulnerable,” Riris said, adding that both authorities and indigenous people, who feel a sense of ownership over them, need to be involved be involved in their protection.

A close-up shows a detail of petroglyphs on Picure Island, Venezuela.  -Philip Riris et al.A close-up shows a detail of petroglyphs on Picure Island, Venezuela.  -Philip Riris et al.

A close-up shows a detail of petroglyphs on Picure Island, Venezuela. -Philip Riris et al.

The ancient works give us a rare glimpse into how indigenous groups of the Orinoco perceived their landscape and made it sacred and instrumental through petroglyphs, said George Lau, professor of art and archeology of the Americas at the University of East Anglia in Britain. . He was not involved in the investigation.

“It also shows the long-term resilience of such art to indigenous landscapes, especially the importance of mythical creatures to local belief systems. “The research is really just the tip of the iceberg for the immensely rich archeology and ancient cultures of this region,” he added.

According to Dr. Alexander Geurds, associate professor of Central and South American archeology at the University of Oxford in Great Britain, this research is an important contribution to the understanding of rock art in northern South America. He was also not involved in the work.

The research goes beyond previous work, Geurds says, because it not only captures the location and style of the sculpted images, but also addresses their extraordinary size. Applying computer-based visual analysis is an innovative step, he added, because it helps understand how the scale of the sculpture compares to the ability to recognize it from afar — a likely scenario if indigenous groups along the Orinoco River were to to travel.

Part of the critical importance of these large-scale sculptures is the collective labor they required: “Particularly at larger rivers and river junctions, these may have been places where people gathered to forge bonds between communities during late pre-Hispanic times,” said Geurds. . “Rapids are also (ironically) where canoe traffic slows down, allowing a suitable theater to view the images. These monumental snakes are silent witnesses of this social world from the past.”

For more CNN news and newsletters, create an account at

Leave a Comment