Why do folk tunes change when they move across ethnic or national boundaries?

Folk tunes change when they cross ethnic or national boundaries primarily because they are subject to the stylistic expectations and musical traditions of the new community that adopts them.12

Because folk music is transmitted through oral tradition, it does not exist in a fixed, standard form. Instead, it is constantly reshaped by communal re-creation, influenced by factors such as individual creativity, memory, and the specific cultural context of the performers. When a song moves into a new region or culture, it is often adapted to align with local aesthetic preferences and established musical norms. For instance, a variant of a song may retain a recognizable relationship to its original form while simultaneously assuming the distinct stylistic traits, scales, or rhythmic approaches characteristic of the new culture's folk music.21

This process of variation ensures that folk music remains a living, evolving reflection of the community that performs it, rather than a static artifact.12