The universality of music is well documented throughout the human species, as well as its diversity in form, genre and style. The genre of folk music has emerged to represent traditional styles of specific cultures and regions throughout hundreds of years of social and cultural evolution. Therefore, by analysing quantitative traits, such as rhythmic function and note substitution, folk melodies across cultures may display similar, synonymous traits highlighting the universality of music. Quantifying folk melodies using the 12-note melodic scale allows for the identification of specific cultural evolutionary trends as well as comparison between melodies and cultures.
10,062 melodies from two samples of Japanese and British-American lyrical folk traditions were analysed, resulting in 328 pairs of highly related melodies being identified. Analogous with the mechanisms of evolution in genetic sequences, note substitutions were more likely to occur at less melodically important notes, yet contrastingly, note deletions or insertions were more common than substitutions. Substitutions occurred more between notes that are closer on the melodic scale compared with notes of greater melodic distance. Notes that fell on ‘stressed’ or rhythmically important beats were less likely to change, as they tended to be more critical to the song’s melody. Despite differences in the scales and tones used, both the British-American and the Japanese samples showed similar results.
Both the patterns seen in note substitutions and in the rhythmic function of notes follow similar rules seen in genetic evolution, with increased changes seen at less functionally important or noticeable notes that are crucial for the effective transfer of the folk melody between generations. Although stylistically and structurally divergent, the folk melodies of both cultures analysed show similar relationships in the evolution of melodies over time. This further highlights the fundamental similarities across seemingly distinct, yet convergent, musical traditions and can perhaps be applicable to other human cultural phenomena. Entry by Claire Shortt