What? The occurrence of human-wildlife interfaces has increased during the Anthropocene, yet we have very little knowledge of the patterns and potentials of cross-species co-construction of culture in these interfaces, which can have significant implications for coexistence. Using a model species for interface research, the long-tailed macaque (Macaca fascicularis), I will investigate the existence, diversity and nature of co-constructed cultures between humans and macaques in urban, rural, historical and novel interfaces Why? When humans and wildlife coexist it can lead to the co-creation of ecological niches and the emergence of cultural traits specific to their shared ecosystems. However, only a few studies have investigated such shared cultures, primarily because much human-wildlife interface research has focused on negative interactions and lacks an interdisciplinary approach. Additionally, the often invoked 'disturbance hypothesis' predicts that human disturbance will decrease wildlife population sizes and thereby reduce the foundations for new cultural features. However, for synanthropic wildlife species the exact opposite may occur. I propose a substantive shift in animal cultural research, to where we perceive and portray humans and wildlife as a part of one another's lives in shared interface ecologies How? I will compare urban and rural interfaces in Malaysia by observing the interspecific interactions between humans and long-tailed macaques and cultural behaviours/patterns. I will also collect data on demography, and environmental and social factors. Furthermore, through our organisation, The Long-Tailed Macaque Project (www.theltmproject.org), I will compare novel and historical interfaces by contacting all project researchers. Finally, I will compare my results with related data from human-macaque interfaces in India, including two other macaque species: the rhesus (Macaca mulatta) and bonnet macaques (Macaca radiata) to further investigate geographical origin effects and macaque-specific cultural patterns, similar or different from those of the long-tailed macaque