A groundbreaking discovery in Southeast Asia has unveiled fossils of the extinct human ancestor Homo erectus, dredged from the seabed during a construction project in the Madura Strait. This remarkable finding highlights an ancient landscape—submerged for millennia—where early hominids thrived along with a diverse ecosystem of flora and fauna. The research, presented in four studies published in the June 2025 issue of Quaternary Environments and Humans, sheds light on the interactions of H. erectus with their environment, showcasing their capabilities as hunters.
Homo erectus, known to be the first hominids that left Africa roughly 1.8 million years ago, migrated to Java, Indonesia, where they thrived until about 108,000 years ago. This new discovery is particularly significant as it is the first instance of H. erectus remains being recovered from the seabeds of this particular region, offering unique insights into their lifestyle and the ecological context in which they lived. The findings build upon previous archaeological work conducted in other submerged areas but elevate the understanding of human evolution in Southeast Asia.
The expansive land of Sundaland, now submerged, once connected Java to the Asian mainland when sea levels were notably lower. Geologist Harold Berghuis had long suspected that dredging activities might yield important fossils, leading him to explore the artificial island created from materials sourced from the Madura Strait. His collection of over 6,300 fossil specimens, now stored at the Bandung Geological Museum in Java, offers a glimpse into an ancient ecosystem and the adaptations of H. erectus in that environment.
Through meticulous analysis of sediment and fossil dating techniques, researchers established that the remains they studied date back between 131,000 and 146,000 years ago, coinciding with the last exposure to sunlight. Among the notable finds were two fragments of H. erectus skull, lending evidence to the species’ occupation of this region. Such fossils not only provide tangible connections to human ancestry but also facilitate reconstructions of the environmental landscape that supported their existence.
The fossil assemblage also revealed a vibrant ecosystem teeming with various species, including turtles and large mammals like buffalo and elephant-like Stegodon. Evidence of hunting activities emerged through cut marks on bones, suggesting that H. erectus exhibited advanced hunting techniques, possibly distinguishing them from their continental counterparts. The remains indicate a targeted hunt strategy focusing specifically on young, healthy animals, hinting at a developed understanding of animal behavior.
Despite these findings, challenges remain due to the absence of identifiable stone tools within the collection. This raises questions about the potential use of alternative materials for tool-making, such as bamboo or shell, which may not have survived the passage of time. Such mysteries underscore the imperative to further investigate the submerged terrains of Sundaland, as they may hold keys to understanding human evolution and dispersal across the region, echoing the calls of archaeologists like Geoff Bailey for a focused effort on underwater investigations.