Aboriginal people harvested this native grass for millennia: Scientists find an odd trait in its DNA

Aboriginal people harvested this native grass for millennia: Scientists find an odd trait in its DNA Scientists have discovered an unusual genetic characteristic in channel millet, a native grass long cultivated by Indigenous Australians. The findings, published in Nature Communications, suggest that the plant’s genetic structure may reflect centuries of human interaction with the species. Researchers from institutions including The University of Sydney and the Australian National University conducted the study, examining samples collected from a site in southwest Queensland, home to the Mithaka people. The Mithaka people, whose ancestral presence in the region dates back thousands of years, have historically relied heavily on plants for sustenance, medicine, and cultural practices. Their relationship with flora is deeply embedded in their way of life, with evidence of extensive plant processing evident in archaeological records. In 2025, researchers identified a large field of channel millet within a broader archaeological landscape, prompting further investigation into its genetic makeup. Channel millet, scientifically known as Echinochloa turneriana, is a hardy grass that thrives in flooded environments. It forms dense stands of tall, swaying seed heads, making it a prominent feature of the Channel Country, a vast expanse of over 280,000 square kilometers in outback Australia. This region, characterized by its intricate network of rivers, supports diverse ecosystems and has been inhabited by Indigenous peoples for millennia. The Mithaka people, who inhabit parts of southwest Queensland, have maintained a close connection with the land, developing sophisticated methods for managing and utilizing local plant resources. Previous research has highlighted the significance of plant use among Indigenous Australians, revealing how they shaped their environment through careful management. For instance, studies have shown that Aboriginal groups in northeastern New South Wales and southeastern Queensland intentionally spread the black bean (Castanospermum australe), a nutrient-rich native food. Similarly, the Mithaka people left behind numerous grinding stone quarries, indicating advanced techniques for processing seeds from various plant species. These sites, collectively forming an interconnected cultural landscape, were recently designated as part of the National Heritage List. The current study focused on the genetic composition of channel millet, a staple in the diets of Indigenous communities. Initial sequencing of the plant’s DNA revealed a striking anomaly: instead of having two copies of each chromosome, as is typical in humans and many other organisms, the plant possesses 12 copies. This phenomenon, known as polyploidy, occurs when an organism inherits multiple sets of chromosomes, often resulting from hybridization or errors during cell division. Polyploidy is commonly observed in plants and can lead to increased adaptability and resilience. The researchers speculate that the repeated duplication of chromosomes in channel millet may have been influenced by prolonged human activity, such as selective harvesting and seed dispersal. Such practices could have inadvertently promoted genetic diversity, contributing to the plant’s unique chromosomal configuration. Further analysis is ongoing, with scientists linking the genetic data to the surrounding archaeological and environmental context. By integrating genomic findings with historical and ecological records, researchers aim to better understand the dynamic interplay between Indigenous peoples and the flora of the Channel Country. This interdisciplinary approach underscores the growing recognition of the value of traditional ecological knowledge in modern scientific inquiry.