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photo from Karline R. L. JanmaatCurrent Project

I am currently studying the ranging behaviour of Taï chimpanzees (Pan troglodytes verus), investigating the extent of their botanical knowledge and the cognitive strategies they use to find ripe fruit. My studies will test for the existence of cognitive capacities that enable mental time travel, such as episodic-like memory and planning skills, a capacity that until today is considered uniquely human. The results are expected to produce novel insights in to human cognitive evolution.

In addition, we will investigate how individuals can benefit from the reservoir of botanical knowledge of other community members and their use of social cues to find food. The fission-fusion system of chimpanzees provides a unique opportunity to investigate the costs and benefits of gregariousness in relation to locating food.

Observations on our target chimpanzees are being conducted over three consecutive years during the same fruiting seasons and comprise consecutive followings of up to 44 days. The data are being combined with long-term data (>11yrs.) on feeding and ranging behaviour of our target individuals, the phenology of the fruit trees within their territory and the locations of all fruit producing tree individuals of the 17 most important species in their core area. My work is conducted in close collaboration with Simone Ban, a PhD student from the University of Cocody in Côte d’Ivoire.

S. Ban, University of Cocody, Côte d'Ivoire, Emma Normand, University of Bordeaux, France, Rebecca Chancellor, University of California in Davis, USA and Colin Chapman, McGill University, Canada and colleagues at the Institute: Prof. Dr. C. Boesch Leo Polansky, Tobias Deschner, Roger Mundry, Julia Riedel and Livia Wittiger.

© Pictures made by Sonja Metzgar and Karline Janmaat © Illustrations made by Irene Goede