ASEAN Beat | Society | Southeast Asia

A 4,000‑yr‑old Rock Painting in Indonesia Offers Clues to One of Humanity’s Greatest Migrations

Austronesia explorers from what is now Taiwan may have leapfrogged to centers of influence, rather than simply advancing to the next nearest island.

This painting of a sunburst may explain why ancient people in Taiwan sailed thousands of kilometers into the unknown.

Some 4,200 years ago, people started to leave what is now Taiwan to migrate to the thousands of islands to the south, spanning as far west as Madagascar in the western Indian Ocean and as far east as Rapa Nui (Easter Island) in the eastern Pacific Ocean.

We can trace this migration through the way language spread, creating the largest-scale language dispersal in prehistory.

But what exactly drove these people to make these distant and dangerous voyages? Our discovery of a 4,000-year-old painting of a sunburst in southeastern Indonesia offers some clues.

Austronesian is a close-knit language family spoken across much of Malaysia, the Philippines, Indonesia, Madagascar, and the Pacific Islands. Some of the major languages in this family include Malay, Javanese, Sundanese, Tagalog, Cebuano and Malagasy.

We know the Austronesian migration began at least around 4,200 years ago, as this is when characteristic Austronesian red pottery and rectangular stone adzes (axe-like tools) appear on islands south of Taiwan.

The extraordinary seafaring abilities of Austronesians were underpinned by the outrigger canoe, but it is unclear which other factors propelled their expansion. Previous models have suggested advancements in rice farming and storage (thanks to pottery) might have fueled population growth, prompting the Austronesian people to migrate to neighboring islands for new farmland. However, rice and pottery are not universal features of Austronesian societies.

An alternative theory is that there was a powerful and charismatic cultural identity shared by the Austronesian people – the kind that attracted outsiders and encouraged daring voyages to remote uninhabited islands.

Finding archaeological evidence for the presence of a past cultural identity is difficult, but rock art does provide a way.

In the 1992 book “State of the Art,” Australian anthropologist Chris Ballard observed there was a style of red rock paintings found mainly in areas where Austronesian is spoken today – eastern Indonesia, Timor, and coastal New Guinea – but not in neighboring parts of these islands where Papuan languages are spoken.

Ballard named this style of painting the Austronesian Painting Tradition (APT). It was characterised by motifs of small human figures, often wielding weapons or on boats, as well as a geometric sun ray of concentric circles with radiating spokes.

The age of this painting tradition has long remained a mystery, however, because of how difficult it is to date art painted on walls.

In 2023, we carried out the first ever archaeological investigation on the island of Wetar in southeastern Indonesia, with colleagues from the Indonesian National Research and Innovation Agency. During this survey we identified a large rock overhang called Huknaur, with APT art on its walls.

We excavated the site in 2024 and were lucky enough to find a stone plaque painted with the characteristic APT sun ray motif, in a layer radiocarbon dated to 4,000 years ago.

The painting on the plaque (scale bar 5 cm). False-color images show different shades (now faded) that were used to paint more concentric circles and........

© The Diplomat