Archaeologists have discovered evidence of mysterious ancient humans on the Indonesian Island of Sulawesi, including stone tools that indicate an unknown ancient human ancestor made the major deep-sea crossing over one million years ago.
The discovery was made near the Island of Flores, the site of the discovery of Homo floresiensis, a hominin whose small stature garnered the nickname “Hobbits” due to its resemblance to the diminutive characters in J.R.R. Tolkien’s novels.
The new excavations did not yield any bone fragments or other biological samples of these ancient islanders, leaving the identity of the mysterious human population unresolved. However, the research team behind the discovery suggests the findings will help fill in critical missing details of the human origin story during the Pleistocene era.
Mysterious Ancient Humans Made Deep Sea Crossing to Reach Island
In recent decades, scientists have found evidence suggesting that ancient Homo Sapiens were crossing the oceans as far back as 50 thousand years ago. Conversely, archaeologists have found very little evidence that early Hominin ancestors were capable of the same nautical feat until the discovery of fossilized remains of a diminutive, 700,000-year-old human ancestor on the island of Flores.
The mere presence of these small hominins suggested the possibility that another type of early human—possibly Homo Erectus—had been able to navigate the ocean before settling on the island, after which small populations may have slowly experienced isolation-based dwarfism over many ensuing generations, resulting in a distinctive “dwarf” species.
In the latest study, Budianto Hakim from the National Research and Innovation Agency of Indonesia (BRIN) and Professor Adam Brumm from the Australian Research Centre for Human Evolution at Griffith University turned to the island of Sulawesi, a neighbor of Flores, for additional clues to this ancient mystery.
According to a statement announcing the team’s study, Hakim led a study team on a series of excavations at a sandstone outcrop located within a modern-day cornfield in southern Sulawesi. The team believes that during the middle Pleistocene, approximately one million years ago, early hominins would have likely targeted the location for hunting and tool making due to its proximity to a local river channel.
After careful excavation of the sandstone’s sedimentary layers, Hakim’s expedition successfully extracted seven stone artifacts. Among the yield were several small, flake-like, sharp-edged stone fragments likely struck from larger sedimentary pebbles. The team said this hardy material that was chipped into effective cutting and shaving tools “had most likely been obtained from nearby riverbeds.”
Dating Suggests Ancient Water Crossing, But Tool-Maker’s Identity Remains a Mystery
As part of the excavation, the team used paleomagnetic dating techniques to determine the date of the sandstone outcropping where the stone tools were discovered. The team also used a separate, direct dating method to determine the age of a pig fossil excavated from the same site. The team said the combined methods yielded a likely date for the artefacts of “at least” 1.04 million years ago.
If correct, the artifacts would predate evidence of hominin occupation at Talepu on Sulawesi, by around 194,000 years ago, and findings of ancient activity on the Philippine Island of Luzon, dated to 700,000 years ago. The new discovery also predates evidence of stone tools at Wolo Sege on the island of Flores, which Brumm’s team had previously discovered, suggesting that ancient hominins lived in the local archipelago, known as Wallacea, from at least 1.02 million years ago.
Wallace said the discovery of ancient human occupation in the region that predates the presence of Hobbits “adds to our understanding of the movement of extinct humans.” The researcher stated that movement in this area across the Wallace Line, “a transitional zone beyond which unique and often quite peculiar animal species evolved in isolation,” could help explain the differences in morphology between modern and ancient hominin species found in the region.
“Sulawesi is a wild card – it’s like a mini-continent in itself,” Bynum explained. “If hominins were cut off on this huge and ecologically rich island for a million years, would they have undergone the same evolutionary changes as the Flores hobbits? Or would something totally different have happened?”
Although the presence of tools makes it likely that early human ancestors crossed the deep sea to arrive on the island, the excavations did not find evidence that would definitively identify the ancient inhabitants
“It’s a significant piece of the puzzle, but the Calio site has yet to yield any hominin fossils, Brumm said. “So, while we now know there were tool-makers on Sulawesi a million years ago, their identity remains a mystery.”
The new study, “Hominins on Sulawesi during the Early Pleistocene,” was published in Nature.
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.