Primatologists in Indonesia have observed a wild male Sumatran orangutan (Pongo abelii) who sustained a facial wound. Three days after the injury he selectively ripped off leaves of a liana with the common name Akar Kuning (Fibraurea tinctoria), chewed on them, and then repeatedly applied the resulting juice onto the facial wound. As a last step, he fully covered the wound with the chewed leaves. This behavior presents the first systematically documented case of active wound treatment with a biologically active plant by a wild animal and provides new insights into the origins of human wound care.
In the early 1960s, the legendary primatologist Jane Goodall first described the presence of whole leaves in the feces of chimpanzees (Pan troglodytes) at Gombe Stream, Tanzania.
By the 1990s, this behavior — now called whole leaf swallowing — was documented at several African great ape study sites, along with bitter pith chewing, and demonstrated to have therapeutic, anti-parasitic function.
Since then, various forms of self-medication have been observed in wild great apes.
In June 2022, Max Planck Institute of Animal Behavior researcher Isabelle Laumer and her colleagues observed a male orangutan in the Suaq Balimbing research area in Gunung Leuser National Park, Indonesia.
“During daily observations of the orangutans, we noticed that a male named Rakus had sustained a facial wound, most likely during a fight with a neighboring male,” Dr. Laumer explained.
Rakus chewed the stem and leaves of Akar Kuning, a climbing plant used in traditional medicine to treat wounds and conditions such as dysentery, diabetes, and malaria.
“This and related liana species that can be found in tropical forests of Southeast Asia are known for their analgesic and antipyretic effects and are used in traditional medicine to treat various diseases, such as malaria,” Dr. Laumer said.
“Analyses of plant chemical compounds show the presence of furanoditerpenoids and…
Read the full article here