For the first time, an orangutan has been observed directly healing a wound

For the first time, an orangutan was observed and documented who used the leaves of a plant to heal a wound by applying certain substances directly to the lesion:this is the case of Rakus, a Sumatran orangutan who was caught while applying chewed plant residues with antibacterial and anti-inflammatory properties directly to the face, probably scarred during a clash with a rival.This is reported by the analyzes included in a peer-reviewed study published on Scientific Reports Of Nature.The research team, in 21 years of observations in the Gunung Leuser national park in Indonesia, had never seen other specimens self-medicating using this plant:"As far as we know, this is the first documented case of active wound treatment with a plant species with medical properties by a wild animal,” said senior study author Caroline Schuppli, an evolutionary biologist at the Max Planck Institute of Animal Behavior.

The observations, as reported by research, began in 1994 and took place in the Suaq Balimbing area, which is a 350-hectare area consisting mainly of peat forests and located in the Gunung Leuser National Park in southern Aceh, Indonesia.The behavior of several Sumatran orangutans was studied and analysed, i.e. one of the three endemic species of the island of Sumatra capable of growing up to 1.30/1.70 meters and weighing between 50 and 90 kilograms.Among these there was Rakus:a male estimated to have been born in the late 1980s first observed in 2009.In 2021 the specimen underwent a growth spurt becoming a mature flanged male:since that time, researchers have observed him fighting with other males to establish dominance, and in June 2022, a field assistant noticed the appearance of an open wound on the right side of the face of the orangutan, probably caused – according to the researchers – by the canines of another male.

Over the next few days, Rakus was observed eating the stems and leaves of the vine Akar Kuning (Fibraurea tinctoria), a species typical of the tropical areas of southern Asia used by the local population to treat diabetes, dysentery, malaria and other diseases.To the curiosity caused by the fact that the orangutans in the area rarely feed on this plant, was soon added the amazement of a totally unexpected behavior and, according to the researchers, observed for the first time ever:field assistants saw Rakus chew without swallowing and use your fingers to spread the juice on the facial wound for a full seven minutes.The specimen then ate the plant again the following day and was reported to have recovered 8 days after the injury.«It is the first study to scientifically demonstrate that an animal uses a plant with medicinal properties applicable to wounds, applying it to the wounds and treating them constantly over a period of time», he declared Michael Huffman, researcher who studies animal self-medication at the Institute of Tropical Medicine at Nagasaki University in Japan.

They had already been in the past observed similar behaviors but none, at least according to the researchers, was comparable to that of Rakus:"THEHis behavior appeared to be intentional.He selectively treated the facial wound on the right flange with the juice of the plant and no other parts of the body.The behavior was repeated several times, not only the plant juice but later also more solid plant material was applied until the wound was completely covered.The entire process took a considerable amount of time,” explained Isabelle Laumer, a primatologist and cognitive biologist at the University of Los Angeles.«The observation suggests that the cognitive abilities necessary for the active treatment of wounds with plants they could be as old as the last common ancestor of orangutans and humans.However, what exactly these cognitive abilities are remains to be investigated.Although this observation shows that orangutans are able to heal their wounds with plants, we do not know to what extent they understand the process,” concluded biologist Schuppli.

[by Roberto Demaio]