Phylo-Analysis of Folk Traditions: A Methodology for the Hierarchical Musical Similarity Analysis

This study introduces and evaluates a new methodology for cross-cultural ethnomusicological analysis of symbolic music. We investigate music similarity in popular traditions rooted in oral transmission by identifying shared patterns at scale across multiple hierarchies. The novelty of our approach lies in expanding musical similarity phylo-analysis, typically adopting alignment metrics that compare entire scores, to structurally aware phrases and macro-structure (i.e., form) alignment. Additionally, we explore patterns derived from multiple representations (chromatic interval, diatonic interval, rhythmic ratios, and a combination of them) to enhance the recognition of musical genres and traditions. Our method is tested on a new dataset of 600 Galician and Irish popular music scores, which includes expert annotations for 21 genres (four shared between the two traditions) and detailed phrase information, all made available as open-access data. The genre separation ratio reveals that alignment metrics applied to phrase and macro structures from chromatic pitch and duration ratios more effectively recognize genres and traditions by analyzing pairwise musical distances. The resulting phylogenetic trees and distance matrices show structural relationships between traditions, genres, and musical scores, facilitating the exploration of cross-cultural influences and enabling the identification of musical scores that share patterns at multiple hierarchies.