The cave of Gua Sireh, in the Malaysian state of Sarawak, features hundreds of centuries-old drawings of people, many of whom seem to be caught in violent battles.
An international team of archaeologists has used carbon dating to confirm the identity of the drawings.
The pictures date from the 17th to 19th centuries, aligning with increasing conflict in the region between the Indigenous inhabitants, including the Bidayuh people, and the encroaching Malay elites.
The team of Australian, Malaysian and New Zealand archaeologists believe this is the first time anyone has used radiometric dating to figure out the age of Malaysian rock art.
“It’s challenging to date rock around the world generally,” explains Professor Paul Tacon, an archaeologist at Griffith University, and co-author on a paper describing the research, published in PLOS One.
While radiocarbon dating can give the age of something up to around 50,000 years old, most pigments – like the red which is the basis for many Malaysian cave paintings – don’t contain any carbon.
“The paintings that are in black, if they were made with charcoal, they could potentially be directly dated,” says Tacon.
Tacon says that there are a few sites in the Malaysian states of Sarawak and Sabah, on the island of Borneo, and “quite a number” in Peninsular Malaysia, with black drawings.
The drawings are similar to those found in the Philippines and Sulawesi, some of which have been dated to 3,500 and 1,500 years old, respectively.
“I’ve been studying this art for about 14 years now with Malaysian archaeologists, and in many areas it’s difficult to get a permit to sample the art because they don’t want to do even minimal damage to it,” says Tacon.
But Tacon and his colleague Mohammad Sherman Sauffi William, curator at the Sarawak Museum Department, got a research permit to take small samples from Gua Sireh. Other evidence has shown that the cave has been occupied by people for at least 20,000 years.
These samples showed them that the pictures were made from 1670-1830, correlating with frontier violence in the region.
“There are figures holding what are essentially fighting swords,” says Tacon.
“Some of these large figures are surrounded by lots of smaller figures. And we know from the history and ethnography that the paintings that we’ve dated are from a period when there was a lot of violence between Malay elites and the local Bidayuh people, and those on the coasts, the Iban.
“So the nature of iconography, the nature of the images, and the dates that we got, sits perfectly with the historical record of frontier violence at that time.”
William, who is a Bidayuh descendant, says that this information also correlates with the oral history of the Bidayuh people.
“The Bidayuh recall Gua Sireh’s use as a refuge during territorial violence in the early 1800s when a very harsh Malay Chief had demanded they hand over their children,” he says.
“They refused and retreated to Gua Sireh, where they initially held off a force of 300 armed men trying to enter the cave from the valley about 60 metres below.
“Suffering some losses (two Bidayuh were shot and seven taken prisoner/enslaved), they saved their children when most of the tribe escaped through a passageway at the back of the largest entrance chamber which leads hundreds of meters through the Gunung Nambi limestone hill.
“The figures were drawn holding distinctive weapons such as a Pandat, which was used exclusively for fighting or protection, as well two short-bladed Parang Ilang, the main weapons used during warfare that marked the first decades of white rule in Borneo.”
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