The role of population size in folk tune complexity

Abstract

A positive correlation between population size and cultural complexity is perhaps one of the most consistent findings in the field of cultural evolution. However, previous findings are largely based on studies of technology and are not necessarily generalisable across diverse cultural domains. We investigate the relationship between population size and complexity in music using Irish folk session tunes as a case study. Using analyses of a large online folk tune dataset, we show that tunes played by larger communities of musicians have diversified into a greater number of different versions but are intermediate in melodic complexity. These results suggest that while larger populations create more frequent opportunities for musical innovation, they encourage convergence upon intermediate levels of melodic complexity due to a widespread inverse U-shaped relationship between complexity and aesthetic preference. Our results show that the relationship between population size and cultural complexity is domain-dependent, rather than universal.

Cultural evolution and music

“…Data on folk melodies and scales, as well as rhythms, have also been used to test cultural evolutionary hypotheses at the population level. For example, it is often assumed that population size and cultural complexity are positively correlated, but Street et al (2021) recently found a non-linear (inverted U-shaped) relationship between population size and musical complexity among Irish folk melodies. Similarly, Le Bomin et al ( 2016) applied phylogenetic analysis to melody and scale data from Gabonese folk songs to conclude that vertical transmission may play a greater role in musical diversity than previously thought.…”

Sequence alignment of folk song melodies reveals cross-cultural regularities of musical evolution

“…1,[24][25][26][27][28] However, attempts to test such proposals quantitatively have focused almost exclusively on Western music. [29][30][31][32][33][34][35][36][37] Whether such regularities are specific to Western music or more general features of human music remains unknown.…”