The study of culture and biology has long stood stratified within the social and natural sciences, a gap that physicist C.P. Snow (1959) famously called "the two cultures." Cultural neuroscience is an emerging, interdisciplinary field that examines the bidirectional influence of culture and genes to brain and behavior across multiple timescales. Integrating theory and methods from cultural psychology, brain sciences, and population genetics, cultural neuroscience is the study of how cultural values, practices and beliefs shape brain function and how the human brain gives rise to cultural capacities and their transmission across macro- (e.g., phylogeny, lifespan) and micro timescales (e.g., situation). The current article presents the aims and methods of cultural neuroscience, highlights recent empirical findings in the field, and discusses the potential implications of this field for bridging the social and natural sciences as well as informing interethnic ideology and population health concerns, more broadly construed.