A team of German and Indonesian researchers announced Thursday that they observed an orangutan using medicinal herbs to treat its wound, the first time an animal has been seen using a plant to heal itself.
Biologists from Germany’s Max Planck Institute for Animal Behavior and Indonesia’s National University watched Rakus, a male orangutan, chew leaves from the native Fibraurea tinctoria plant, apply juice from the leaves onto a facial wound he had suffered, then cover the wound entirely with the leaves.
Primatologist Jane Goodall observed whole leaves from medicinal plants in the droppings of chimpanzees in the 1960s, the researchers noted in the introduction to their study, published in the journal Scientific Reports Thursday.
Fibraurea tinctoria, known in Bahasa Indonesia as “akar kuning,” is used in traditional medicines for its healing effects.
The wound didn’t become infected and had closed after five days, the Max Planck Institute said in a statement.
The wound completely healed after a month, as Rakus continued to use the plants to heal his wound.
“He repeatedly applied the paste, and he later also applied more solid plant matter. The entire process lasted really a considerable amount of time — that’s why we think that he intentionally applied it,” Max Planck Institute biologist Isabella Laumer told the BBC.
Researchers do not know whether the method is unique to Rakus or whether it is endemic to the orangutans in the Suaq Balimbing protected forest on the Indonesian island of Sumatra.
“Orangutans at the site rarely eat the plant. However, individuals may accidentally touch their wounds while feeding on this plant and thus unintentionally apply the plant’s juice to their wounds. As Fibraurea tinctoria has potent analgesic effects, individuals may feel an immediate pain release, causing them to repeat the behavior several times,” researcher Caroline Schuppli said in the statement.
However, Ms. Schuppli qualified, Rakus was not born in the Suaq Balimbing forest, so he may have learned it elsewhere.