The Wallacean Islands were a popular place for our ancient ancestors. And as it turns out, our ancient ancestors reached some of these islands, which extend between Asia and Australia, remarkably early on.
According to a new paper published in Nature, a stone tool discovery suggests that the hominins appeared on the Wallacean island of Sulawesi around 1.04 million years ago or more, which is hundreds of thousands of years before traditionally thought. In fact, the age of these tools reveals that the established presence of ancient humans on Sulawesi is about as old, or older, than the established presence of ancient humans on the Wallacean island of Flores, which is famous for housing the later remains of the “hobbit human,” Homo floresiensis.
The discovery helps researchers retrace how hominins moved through the Wallacean Islands — locations where humans and other animals have evolved several surprising traits, like the small size of the H. floresiensis, all thanks to their separation from other populations.
“This discovery adds to our understanding of the movement of extinct humans across the Wallace Line, a transitional zone beyond which unique and often quite peculiar animal species evolved in isolation,” said Adam Brumm, a paper author and an archaeologist at Griffith University in Australia, according to a press release.
Read More: Meet Homo floresiensis: The Real-Life Hobbits of Indonesia
Stone Artifacts from Early Hominins
Stone tools were excavated from Calio, Sulawesi, and dated to over 1.04 million years ago. The scale bars are 10 mm. (Image Credit: M.W. Moore/University of New England)
Researchers have known that early hominins lived on Sulawesi for around a decade. Back in 2016, they reported their findings of stone artifacts on the island, which indicated that ancient humans arrived there around 194 thousand years ago at a minimum.
But the new research shows that the hominins actually lived on Sulawesi a lot earlier than that, though how they got there is a lot less clear. Describing seven stone tools from the sandstone at Calio, an archaeological site on the southern side of the island, the paper suggests that ancient humans occupied Sulawesi around 1.04 million years ago at least.
The artifacts themselves are small, sharp fragments, or flakes, that the island’s inhabitants likely shaped from larger stones. Testing the sedimentary layer in which these tools were found, as well as an animal fossil that was acquired from the same sedimentary layer, the researchers determined the date of these artifacts, reshaping the story of Sulawesi in the process.
Read More: The Flores Man Hobbits: Are They Still Alive?
The Sulawesi Hominins and the Flores Hobbits
While the results reimagine the history of humans on the island of Sulawesi, they also reimagine Wallacean history as a whole. Previously, the earliest evidence of hominins on these islands came from the island of Flores, where stone tools had hinted at an ancient human occupation since around 1.02 million years ago or earlier. Later research revealed that these hominins may have been Homo erectus, but regardless of their identity, it is thought that these individuals transformed following their arrival on Flores, transitioning over hundreds of thousands of years into the island’s tiny hominins, thanks to the process of island, or insular, dwarfism.
As such, the new paper provides important insights into when humans arrived in the Wallacea islands and where, though the exact identity of the Sulawesi hominins is a subject for future research to tackle.
“It’s a significant piece of the puzzle, but the Calio site has yet to yield any hominin fossils,” Brumm said in the release. “While we now know there were tool-makers on Sulawesi a million years ago, their identity remains a mystery.”
Also mysterious is how the hominins arrived on the island, and whether their time there encouraged any evolutionary transformations like those seen in the hominins of Flores (which also happens to be a much smaller island than Sulawesi).
“Sulawesi is a wild card — it’s like a mini-continent in itself,” Brumm said in the release. “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?”
Read More: Smallest Ever Human Arm Bone Found as a Piece of the Hobbit Origin Puzzle
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Nature. Hominins on Flores, Indonesia, By One Million Years Ago
Nature Communications. Early Evolution of Small Body Size in Homo floresiensis
Sam Walters is a journalist covering archaeology, paleontology, ecology, and evolution for Discover, along with an assortment of other topics. Before joining the Discover team as an assistant editor in 2022, Sam studied journalism at Northwestern University in Evanston, Illinois.