An international archaeological team has investigated the possibility of coexistence between Homo sapiens and an archaic, extinct human species on the Indonesian island of Sulawesi over 65,000 years ago. The research also explores potential interactions between these groups.
The study, led by Griffith University and published in PLOS One, details excavations at Leang Bulu Bettue, a limestone cave in the Maros-Pangkep karst area of southern Sulawesi. The findings reveal a deep sequence of archaeological deposits extending at least eight meters below the current ground surface, indicating human activity predating the arrival of Homo sapiens on Sulawesi.
Chronological Context
Previous research indicated archaic hominins occupied Sulawesi from at least 1.04 million years ago. Modern humans (Homo sapiens) are understood to have reached the island before the initial peopling of Australia, approximately 65,000 years ago.
Basran Burhan, a PhD candidate from Griffith University, stated that the depth and continuity of the cultural sequence at Leang Bulu Bettue positions the cave as a key site for examining whether these two human lineages overlapped chronologically.
Archaeological Evidence
Excavations since 2013 have uncovered a long and preserved record of human occupation. The deepest evidence dates to a period between 132,300 and 208,400 years ago. This early occupation phase included evidence of animal butchery and stone artifact production, such as heavy-duty stone tools known as ‘picks.’ These activities occurred prior to Homo sapiens’ migration out of Africa.
Professor Adam Brumm noted that these activities represent an archaic hominin cultural tradition that continued on Sulawesi into the Late Pleistocene.
Cultural Transition
Around 40,000 years ago, the archaeological record at the site indicates a significant shift. An earlier occupation phase, characterized by cobble-based core and flake technologies and faunal assemblages dominated by dwarf bovids (anoas) and now-extinct Asian straight-tusked elephants, was replaced by a new cultural phase.
Mr. Burhan explained that this later phase featured a distinct technological toolkit and the earliest known evidence for artistic expression and symbolic behavior on the island, traits associated with modern humans. The observed behavioral change between these phases may signify a major demographic and cultural transition on Sulawesi, potentially reflecting the arrival of Homo sapiens and the replacement of the earlier hominin population.
Implications
The research team suggests that Leang Bulu Bettue may provide the first direct archaeological evidence for chronological overlap and potential interaction between earlier human species and Homo sapiens in Wallacea. These findings underscore Sulawesi’s importance for understanding human evolution in Island Southeast Asia and offer new avenues for investigating how different human species coexisted, adapted, and eventually disappeared.
Professor Brumm highlighted that further deep excavation at Australian sites would not yield pre-Homo sapiens evidence, unlike Sulawesi, which harbored hominins for a million years prior to Homo sapiens’ arrival.
Mr. Burhan added that several more meters of archaeological layers might exist below the current excavation depth at Leang Bulu Bettue, suggesting that further work could reveal new discoveries related to the early human narrative on the island and potentially more broadly.