Some of the world’s oldest cave art is being lost due to the detrimental effects of climate change, according to a new study on Sulawesi’s Pleistocene rock art conducted by Jill Huntley and others from the Place, Evolution and Rock Art Heritage Unit at Griffith University in Australia. In southern Sulawesi, Indonesia, more than 300 cave sites are at risk of deterioration—this notably includes some of the earliest cave art ever created, even older than some better-known sites in Europe such as Lascaux and Chauvet.
The art was created using red and mulberry pigments, and includes hand stencils, animal depictions, and images of human-animal hybrids. The Sulawesi caves are home to the oldest animal depiction—a warty pig that is at least 45,500 years old—as well as the oldest hand stencil in the world, made more than 39,900 years ago. One cave even contains what researchers describe as “possibly the earliest known narrative scene in prehistoric art” depicting a hunting scene.
Salt, heat, and extreme weather events are contributing to the degradation of these important sites, researchers explained. The constant cycling between dry conditions and monsoon rainfall is causing a buildup of salts on the cave surfaces, leading to exfoliation. “When the solution evaporates, crystals form, expand, and contract as the environment heats and cools, causing repetitive strain.” This salt crystallization, also known as haloclasty, damages the limestone surfaces inside the caves, thereby creating cracks in the rock’s surfaces and causing the artwork to flake from it.
The area in which Sulawesi is located (the Australasian monsoon region) is the most atmospherically dynamic on earth—making it particularly susceptible to anthropogenic climate change—and places it at high risk of losing an invaluable part of early human heritage. Researchers found that the rate of exfoliation is increasing. Local communities that have watched over the rock art sites for generations say the destruction has grown rapidly, with more loss in recent decades than at “any other time in living memory.”
New rock art sites are found in Sulawesi every year, and some of the caves have yet to be explored. As the researchers explain, our climate crisis is “hastening the deterioration of the unique, irreplaceable record of early human artistic culture.”