On the wall of a cave deep in the jungles of Borneo, there is an image of a thick-bodied, spindly-legged animal, drawn in reddish ocher.
It may be a crude image. But it also is more than 40,000 years old, scientists reported on Wednesday, making this the oldest figurative art in the world.
Until now, the oldest known human-made figures were ivory sculptures found in Germany. Scientists have estimated that those figurines — of horses, birds and people — were at most 40,000 years old.
Researchers have found older man-made images, but these were abstract patterns, such as crisscrossing lines. The switch to figurative art represented an important shift in how people thought about the world around them — and possibly themselves.
The finding also demonstrates that ancient humans somehow made the creative transition at roughly the same time, in places thousands of miles apart.
“It’s essentially happening at the same time at the opposite ends of the world,” said Maxime Aubert, an archaeologist at Griffith University in Australia and a co-author of the report, published in the journal Nature.
Archaeologists have been discovering cave paintings and ancient sculptures for centuries, but it was only in the mid twentieth century that it became possible to precisely determine their age.
Traces of radioactive carbon are present in some types of art, and scientists gauge their age by measuring how long the carbon has been breaking down.
In the 1950s, radiocarbon dating on paintings in the Lascaux Cave in southern France showed that the images — of horses and other animals — were made 15,500 years ago.
On further investigation, the Lascaux paintings were shown to be 18,000 years old, making them the oldest artwork known at the time.
Eventually even older art came to light. Another French cave, called Chauvet, is decorated with drawings of animals that researchers estimate date back as far as 37,000 years.
In 2003, Nicholas Conard of the University of Tübingen in Germany discovered the ivory figurines, which turned out to be far older: up to 40,000 years old.
For years, those sculptures stood out as the oldest figurative artworks on the planet. “It was very lonely for a long time,” said Dr. Conard.
Scientists suspected that still older art was out there, but radiocarbon dating has limits. Many cave paintings lack the carbon required to date them.
Moreover, the half-life of radioactive carbon is only 5,730 years. In a sample that’s 40,000 years old or older, all of the carbon required to date it may be long gone.
In recent years, scientists have developed a new dating method.
When water trickles down cave walls, it can leave behind a translucent curtain of minerals called a flowstone. If a flowstone contains uranium, it will decay steadily — and at a predictable rate — into thorium.
In 2014, Dr. Aubert and his colleagues dated the age of a flowstone that covered a picture of a pig-like animal called a babirusa in a cave in Sulawesi. They discovered that the image was at least 35,400 years old.
That ancient age stunned Dr. Aubert and his colleagues, and they grew eager to use their method on other cave art. Pindi Setiawan, an archaeologist at Bandung Institute of Technology in Indonesia, invited Dr. Aubert and his colleagues to try it in Borneo.
Dr. Setiawan and Adhi Agus Oktaviana, of the Indonesian National Center for Archaeological Research, had spent years studying drawings in remote mountain caves there.
Getting to the site was not easy. The team had to travel upriver by boat into the rain forest, then to backpack up mountains for days, hacking a path with machetes.
Over the course of two field seasons, the researchers visited six caves. They removed bits of flowstone overlying paintings and used the samples to date the minimum age of the artwork underneath.
The scientists discovered flowstones underneath some images, as well; these samples allowed them to determine a maximum age.
The earliest art in the caves, the researchers found, were reddish-orange hand outlines and drawings of animals. The oldest of all was covered by a flowstone that formed 40,000 years ago.
That drawing depicts a four-legged animal that Dr. Aubert suspected was a species of wild cattle called a banteng.
Since the 40,000-year-old flowstone covers the banteng image, the artwork must be older than that — and thus the oldest known figurative art on the planet.
It’s hard to say when people first began to make these cave drawings, but one intriguing clue comes from a hand stencil. A flowstone atop it is 23,600 years old, while another underneath is 51,800 years old.
Combining the evidence from this stencil and the banteng image, it’s possible that people started making art in the Borneo caves sometime between 52,000 years ago and 40,000 years ago.
The new discovery indicates that people in Borneo were already making figurative images at the same time as people in Europe — or perhaps even thousands of years beforehand.
Now Dr. Aubert and other researchers are puzzling over what triggered these bursts of creativity.
One thing is clear: Figurative art came late in the history of our species.
The oldest fossils of Homo sapiens, found in Morocco, are 300,000 years old. A study last year of genetic diversity among people today indicates that populations began diverging from one another in Africa between 260,000 and 350,000 years ago.
Today, every culture makes art of some sort, and it is likely that humans in Africa over 200,000 years ago had the capacity to create it.
But for thousands of generations, there’s no evidence that people actually made figurative art. The closest thing to it are abstract engravings etched on shells or pieces of ocher.
Only much later did our species expand out of Africa. They arrived in Southeast Asia and Australia perhaps as early as 70,000 years ago. Modern humans didn’t get to Europe until much later, about 45,000 years ago, researchers suspect.
Dr. Aubert speculated that over thousands of years, certain societies of hunter-gatherers found places with good food supplies, or developed new kinds of tools, and thus attained denser populations.
In those societies, people may have begun communicating with symbolic images and pictures.
“When they arrive at a certain place and there’s an increase in population, they make rock art,” said Dr. Aubert.
The early images and figures might have illustrated stories contained vital information for how to survive in hard times, Dr. Conard said.
Or perhaps the drawings helped joined people as a group, encouraging them to cooperate — “a kind of glue to hold these social units together,” he said.
If that’s the case, then ancient figurative art may yet turn up in other places where early humans reached dense populations, including Africa, Asia or Australia.
There are many examples of early cave art that have yet to be dated with the latest flowstone method. “They’re just everywhere,” Dr. Aubert said.
For now, however, he just wants to go back to the caves of Borneo and figure out how ancient humans made those remarkable images. Aside from their artwork, no one has found a trace of the people who once lived there.
“We want to go there and dig,” said Dr. Aubert. “We want to know who those people were. We want to know how they lived. We want to know everything.”