Orangutan Observed UsingMedicinal Plantto Treat Wound in Groundbreaking Discovery

In a remarkable observation, researchers have documented a wild orangutan in Indonesia using a medicinal plant to self-medicate a painful wound, marking the first known instance of wound treatment with a potent plant by a great ape species. The groundbreaking discovery, made in the Suaq Balimbing research area of Gunung Leuser National Park in June 2022, provides new insights into the cognitive abilities and evolutionary origins of self-medication behaviors in animals.

Why this matters: This discovery sheds light on the remarkable cognitive abilities of orangutans and highlights the urgent need to protect these critically endangered species and their habitats from threats such as deforestation and climate change. It also raises intriguing questions about the evolution of medicine and whether similar practices might have been present in a common ancestor shared with humans millions of years ago.

The adult male Sumatran orangutan, named Rakus, was observed by field researchers plucking and chewing the leaves of a tropical liana plant, scientifically known as Fibraurea tinctoria. This plant is commonly used in traditional medicine by local communities in Southeast Asia to treat various ailments, including pain and inflammation. After chewing the leaves, Rakus deliberately applied the plant juices to an open wound on his right cheek and covered it with the chewed leaf material, creating a makeshift poultice bandage.

Isabelle Laumer, a biologist at the Max Planck Institute of Animal Behavior and lead author of the study, emphasized the significance of this observation: "This is the first time that we have observed a wild animal applying a quite potent medicinal plant directly to a wound." The research team, consisting of cognitive and evolutionary biologists from the Max Planck Institute and Universitas Nasional in Indonesia, had been studying the orangutan population in the area since 1994 but had never witnessed such behavior before.

Rakus's innovative use of the medicinal plant proved effective, as photographs taken by the researchers show the wound had fully closed within a month without any complications. The orangutan's choice to rest more than usual during his recovery also likely contributed to the healing process. "Sleep positively affects wound healing, since during sleep, the release of growth hormone, protein synthesis, and cell division increase," explained Laumer.

The exact mechanism by which Rakus learned this self-medication technique remains unclear, but the researchers propose two possible explanations. He may have discovered it through independent trial and error, a process known as "accidental individual innovation." Alternatively, Rakus, who was born and lived part of his life outside the study area, could have learned the behavior by observing other orangutans not habituated to theresearch site.

This groundbreaking observation adds to a growing body of evidence suggesting that self-medication behaviors exist in other great ape species, such as chimpanzees and gorillas. These primates have been documented using plants to treat various ailments, including intestinal parasites and skin infections. The fact that both African and Asian great apes exhibit these behaviors raises intriguing questions about the evolution of medicine and whether these practices might have been present in a common ancestor shared with humans millions of years ago.

The researchers plan to continue monitoring the orangutan population in Suaq Balimbing to determine if Rakus's innovative wound treatment is a unique occurrence or a more widespread behavior among the critically endangered species. This discovery not only sheds light on the remarkable cognitive abilities of orangutans but also highlights the urgent need to protect these primates and their rapidly disappearing rainforest habitats from the threats of deforestation, habitat fragmentation, and climate change.

Key Takeaways

• Wild orangutan Rakus used a medicinal plant to treat a painful wound in Indonesia.
• This is the first known instance of wound treatment with a potent plant by a great ape species.
• Rakus applied plant juices to the wound and covered it with chewed leaves, creating a makeshift poultice.
• The wound fully closed within a month without complications, showing the effectiveness of the treatment.
• This discovery highlights the need to protect orangutans and their habitats from deforestation and climate change.