Grant: Discovery Grants Program - Individual

I study behavioural innovations and cultural traditions in monkeys. This topic intrigues psychologists and biologists alike because culture is a social (rather than genetic) means by which traits can be inherited. I aim to shed light on how cultural patterns arise and change over time by studying proximate (i.e., genetic, environmental, cognitive, demographic, social) and ultimate (i.e., adaptive, phylogenetic) influences. While most primate cultures are considered adaptive - like chimpanzee tool use - I explore the proximate and ultimate causes of non-adaptive behavioural traditions. By focusing on such exceptions to the rule, I believe that the study of these phenomena can further our understanding of evolutionary theory. I will develop three complementary projects that explore group-specific behavioural patterns in free-ranging Balinese long-tailed macaques. These include: 1) stone handling, a form of solitary object play which involves the manipulation of stones; 2) eye covering play, which involves deliberately covering one's eyes with objects; and 3) bartering objects for food, which takes place when a monkey robs a human of objects that have no intrinsic value for the monkey, but that are valuable to the human (e.g., eye-glasses). These objects are then used as tokens by the monkeys, who exchange them for food. My long-term goal is to extend the study of non-adaptive cultural behaviours to other macaque species and use these comparative analyses to model the forces that have shaped our own culture during the course of human evolution. In conducting this research, I will explore how seemingly non-adaptive behaviours may lead to adaptive outcomes for the individual, the group, and the species. For example, I will examine whether individual differences in the expression of eye covering play can be used to predict the development of general sensorimotor coordination. I will also examine whether stone tool use is more likely to emerge in groups or species where stone handling (i.e., stone play) is a well-established cultural practice. Non-adaptive and arbitrary cultural activities abound in humans (e.g., superstitious practices, artistic choices, greeting conventions). My research examines the mechanisms and evolutionary significance of such activities, which have no obvious survival or reproductive value. In doing so, it provides insights into general evolutionary patterns and processes - including adaptations and constraints - and the variety of behaviours they produce. Ultimately, my research can shed light on human physical and social cognition, material and symbolic culture, and token economy.