A wealth of cave paintings have been discovered on a small Indonesian Island. The art sheds light on early trade, possibly initiating newly hierarchical societies, a process that has been very poorly documented elsewhere.
When Professor Susan O'Connor of the Australian National University traveled to the island of Kisar she didn't expect archeological riches. Indeed, she told IFLScience, she went partly to learn if an island this small could support a permanent population prior to the arrival of agriculture in the region.
However, to begin with, locals said they knew nothing of any cave art, something people would have been expected to notice on an island just 81 square kilometers (32 square miles). After showing them images of cave art from nearby Timor, it jogged memories so that she was directed to some rock shelters, which were indeed rich in paintings. On further investigations, O'Connor has found an astonishing abundance of Kisar art, far beyond anything that would be expected for somewhere so small.

The paintings bear a very strong resemblance to those found in Timor, but also to some in more distant islands. O'Connor argues in the Cambridge Journal of Archaeology this indicates the dispersal of a powerful shared symbolic system, which appeared sometime between 2,000-3,000 years ago.
The art contains a mix of large geometric symbols and smaller drawings that “Depict boats, dogs, horses, and people often holding what look like shields," O'Connor said in a statement. "Other scenes show people playing drums, perhaps performing ceremonies.”
The paintings include scenes reminiscent of those cast on Dong Son bronze drums from Vietnam, which were first made about 2,500 years ago. These drums have been found on islands in Eastern Indonesia, indicating maritime trade across the archipelago – an enormous distance for that time.

O'Connor believes the arrival of distantly traded metal goods, for which the Kisar people may have exchanged beeswax, probably changed the area's societies, creating a more hierarchical structure. The people who had achieved elite status through the control of prestige goods advertised this fact in paint.
On some other islands, similar art has been thought to represent the earliest billboards, located on cliff-faces where they could be seen from the ocean. O'Connor told IFLScience the Kisar figures are so small it is necessary to look closely to see them, but the larger images might still have served as messages to other islanders, possibly representing clan markings. Meanwhile, the smaller and more subtle pictures may have been used in ceremonies. “When [former president] Xanana Gusmão visited the far east end of Timore Leste, local residents held a ceremony for him on one of the rock shelters there with paintings,” O'Connor said. “So they are still revered. The same could have been true on Kisar until a few centuries ago.”
