Diversity of items of low nutritional value ingested by chimpanzees from Kanyawara, Kibale National Park, Uganda: an example of the etho-ethnology of chimpanzees

For more than 30 years, field studies have shown that chimpanzees ingest items of low nutritional value such as rough leaves,, bitter stems and clay, apparently thereby protecting themselves against parasites and modulating their health. The authors describe the diversity and the biological activities of items of low nutritional value used by Kanyawara chimpanzees in Uganda, according to scientific observations enriched by the viewpoints of local field assistants and a traditional healer. Their perception of chimpanzees' behaviour and the overlap with human medicinal uses led the authors to explore chimpanzee behaviour in a comparative cultural perspective. In spite of the rarity of such observations on wild individuals, study of self-medicative practices offers the opportunity to suggest an epistemology of the chimpanzee so as to better understand the acquisition and transmission of behaviours linked to diseases.