In a striking demonstration of animal intelligence, Rakus, a male Sumatran orangutan, utilized natural medicine to treat a wound he acquired during a conflict with another orangutan in June 2022. This incident took place at the Suaq Balimbing research site in Indonesia, a protected rainforest habitat home to critically endangered Sumatran orangutans. After sustaining a facial injury below his right eye, Rakus was observed using the leaves of the Akar Kuning plant, known scientifically as Fibraurea tinctoria. This particular plant is seldom consumed by orangutans but is noted for its medicinal properties, including antibacterial and anti-inflammatory effects. Rakus processed the leaves in his mouth to extract the juice, which he then applied to his wound, and also ate some of the plant material.

The implications of Rakus’ behavior are profound, as it showcases not only self-awareness but also an understanding of botanical medicine. The study, led by Isabelle Laumer and Caroline Schuppli of the Max Planck Institute of Animal Behavior, was published in the journal Scientific Reports. They noted that Rakus’ treatment was methodical and targeted, focusing exclusively on the injured area and repeated over time until the wound healed completely within five days. This case highlights the cognitive capabilities that might date back to the last common ancestor of orangutans and humans, nearly 13 million years ago. The researchers believe that such behavior could either be learned through social interaction within their community or through accidental discovery, a testament to the complex problem-solving abilities of orangutans.