Jungle Medicine: Orangutan’s Healing Secret Revealed

In 2022, scientists conducting research in Gunung Leuser National Park on Sumatra Island, Indonesia, discovered that a 30-year-old male orangutan named Rakus (the scientific name for Sumatran orangutans is Pongo abelii) was treating a wound on his face with a plant known for its antibacterial properties. This finding marked a first in the scientific community.

Primates use plants for their healing properties; this is well-known. In the 1960s, Jane Goodall observed whole medicinal plant leaves in the feces of chimpanzees in Tanzania. This might have been an attempt to rid themselves of parasites during times of increased disease risk. Professor Anne Pusey, an evolutionary anthropologist from Duke University, also noted that primates in their natural habitats have previously cleaned their wounds with plant leaves, although these plants were not identified.

Rakus, who is believed to have been injured during a dominance struggle with another male, chewed the leaves of a vine called Akar Kuning in the local language a few days later, turning them into a paste, which he then applied to his wound. The scientific name for this plant is Fibraurea tinctoria, and it is commonly used by the local people for its healing properties, such as in the treatment of diabetes, dysentery, and malaria. However, this plant is almost never part of the orangutans’ diet, meaning it is not a food they typically consume. Rakus chewed the leaves for seven minutes, repeatedly applying the leaf juice to his wound and continued to consume it for thirty more minutes. He then covered the wound with the leaf paste, similar to dressing a wound. The next day, he repeated the process, and eight days later, his wound was almost completely closed. About a month later, it had healed with almost no visible scar.

During their 21 years of studies, scientists observing Rakus had never seen an orangutan use Akar Kuning to treat itself. This could be because orangutans rarely injure each other, or because Rakus is the only individual who knows this treatment method. It is possible that he accidentally touched the plant to his wound while consuming it and continued the application after feeling relief. However, he may have also learned this behavior from another individual when he was younger.

Regardless, this is a brand-new discovery, and it is the first recorded instance of an orangutan systematically treating an external wound with a plant known for its medicinal properties. Rakus’ behavior raises many questions about how he acquired this knowledge. This significant development suggests that the roots of modern medicine may date back hundreds of thousands of years, and from an evolutionary perspective, could shed light on how our ancestors developed natural healing abilities.