Ecological and Cognitive Influences on Orangutan Space Use

Many primates depend on resources that are dispersed non-uniformly. Primates able to encode the locations of such resources and navigate efficiently between them would gain a selective advantage. However, little is currently known about the cognitive mechanisms that help primates achieve this efficiency in the wild. The presence habitual route networks in some primate species suggests they may navigate using route-based cognitive maps for encoding spatial information. However, little is known about factors that influence where such route networks are established. Recent evidence of habitual route networks in wild orangutans makes them ideal candidates for examining factors that affect the establishment and use of such networks. I completed three studies using new methodology to examine ecological and cognitive factors that may affect habitual route networks in wild orangutans living in Kutai National Park, East Kalimantan, Indonesia. Results suggest that orangutan habitual route networks are likely the product of both local ecological considerations and how they cognitively encode and use spatial information. Results imply that the spatial configuration of habitual route networks may primarily be a product of local ecology, whereas how orangutans use them day-to-day may be a product of both local ecology and sophisticated cognitive strategies that may include cognitive maps. These studies demonstrate the utility of using modern mapping software and machine learning technology for applications in primate behavior and ecology.