Borneo Orangutans Treat Themselves With Forest Plants

Orangutans living in Borneo's rainforests appear to deliberately select and combine certain plants in a way that resembles medical treatment. Observations gathered over two decades show that the animals consume specific plants with medicinal properties unexpectedly often and frequently together. The same plants are known from the traditional knowledge of local indigenous peoples.

The behaviour of orangutans living in Borneo's rainforests has surprised scientists: the primates appear to seek food in a manner that suggests deliberate self-treatment. Observations gathered over two decades describe how the animals select particular plants and combine them more frequently than expected, remarkably resembling the logic of a medical treatment plan.

Plant selection is not random

What caught researchers' attention was the fact that many of the plants that orangutans regularly consume are known to have properties used in human medicine. The animals do not select these plants merely for their caloric content, but combine them according to specific patterns. This suggests that the behaviour may be something more than mere instinct.

Deep in Borneo's peat forests, it was observed that apes consume certain plants together and do so more frequently than diet logic alone would explain. Some of these plant combinations align remarkably precisely with what local indigenous peoples use in traditional medicine.

An ancient knowledge store in the animal kingdom

The question of whether this constitutes deliberate self-treatment or ingrained instinct remains open for scientists. Yet there is no getting around the fact that indigenous peoples of Borneo have used similar plants for centuries, connecting forests, traditional knowledge, and modern science in an unexpected way.

The findings open new questions about the cognitive abilities of primates and raise a broader question of significance: what part of natural knowledge lies hidden in forests that we are only beginning to understand?