Application of insects to wounds of self and others by chimpanzees in the wild

Abstract

Self-medication refers to the process by which a host suppresses or prevents the deleterious effects of parasitism and other causes of illness via behavioural means¹. It has been observed across multiple animal taxa (e.g. bears, elephants, moths, starlings)², with many case studies in great apes^1,3. Although the majority of studies on self-medication in non-human primates concern the ingestion of plant parts or non-nutritional substances to combat or control intestinal parasites⁴, more recent examples also report topical applications of leaves or other materials (including arthropods) to skin integuments³. Thus far, however, the application of insects or insect parts to an individual's own wound or the wound of a conspecific has never been reported. Here, we report the first observations of chimpanzees applying insects to their own wounds (n = 19) and to the wounds of conspecifics (n = 3).