Fruit sharing between wild adult chimpanzees (Pan troglodytes schweinfurthii): a socially significant event?

Food-sharing is a habitual aspect of chimpanzee (Pan troglodytes) life, although sharing of plant foods between unrelated adults is rare. Observations of such behaviour have typically been interpreted as the outcome of a process by which individuals, unable to otherwise gain access to the food, manage to obtain a nutritional benefit. Here we present behavioural details and acoustic analysis from an observation of food sharing between unrelated adult wild chimpanzees that we suggest cannot be explained using traditional nutrition-based models. Instead we propose the exchange is only understandable as a socially important event and we cite two further observations from the same population that support this suggestion.