Scientists reported that an orangutan appeared to treat a wound using medicine from a tropical plant, showcasing how some animals use natural remedies to heal themselves. Rakus, an adult male orangutan, was observed plucking and chewing leaves from a medicinal plant known for pain relief and anti-inflammatory properties in Southeast Asia. He then applied the plant juices to an injury on his right cheek using his fingers and used the chewed plant as a makeshift bandage, covering the wound.

This behavior, documented in a new study published in Scientific Reports, marks the first time a wild animal has been observed directly applying a potent medicinal plant to a wound. The observation was made by Ulil Azhari, a field researcher at the Suaq Project in Medan, Indonesia, in 2022. Photographs revealed that the wound closed within a month without complications.

While scientists have been studying orangutans in Indonesia's Gunung Leuser National Park since 1994, this behavior had not been previously observed. Emory University biologist Jacobus de Roode, who was not part of the study, suggested that this behavior is likely an example of self-medication, noting that the orangutan applied the plant specifically to the wound and not to any other part of its body.

Co-author Caroline Schuppli from Max Planck suggested that Rakus may have learned the technique of using medicinal plants from other orangutans living outside the study area and beyond scientists' regular observations.

Rakus, who was born and spent his early years outside the study area, likely got injured during a confrontation with another animal. It remains unknown if Rakus had previously treated other injuries using similar methods.

The use of plants for self-medication is not unique to Rakus. Other primates have been observed using plants for medicinal purposes as well. Bornean orangutans, for instance, rub themselves with juices from medicinal plants, possibly to alleviate body pains or repel parasites. Chimpanzees in various locations have been seen chewing bitter-tasting plant shoots to soothe stomach discomfort, while gorillas, chimpanzees, and bonobos swallow specific rough leaves whole to eliminate stomach parasites.

Tara Stoinski, president and chief scientific officer of the Dian Fossey Gorilla Fund, who was not involved in the study, raised an intriguing question: "If this behavior exists in some of our closest living relatives, what could that tell us about how medicine first evolved?"