Institute of Formal and Applied Linguistics
Charles University, Czech Republic
Faculty of Mathematics and Physics
Genome of Melody: Studying Gregorian chant with phylogenetics
Evolution has provided a remarkably elegant theory underpinning the diversity of life on Earth. The field of Cultural Evolution has since the 1970s been working towards a similar theory of principles that govern change across diverse domains of culture. We apply CE to learn more about a large European medieval musical tradition: Gregorian chant.
Chant was a central musical tradition in Medieval Latin Europe: any Latin Christian liturgy, such as the weekly Sunday mass, involved prescribed chants as a major part of the ritual. Its melodies are sacred objects, obligating practitioners to conserve them exactly. Nevertheless, a single chant rarely has the exact same melody in any two surviving manuscripts. What is the structure of this diversity? Do „melodic dialects“ exist, and if yes, along what lines?
Choosing a set of analogies between biological evolution and historical processes of Gregorian chant transmission, we recover these “melodic dialects” using phylogenetic methods. We show that phylogenies recover historically plausible patterns of chant melody evolution. Some, but not all, institutional networks play a more prominent role than geographic proximity; despite adjacent musical traditions developing over centuries, time plays little role. Additionally, extreme phenomena in the inferred phylogenies draw attention to exceptional historical circumstance. By careful application of CE theory, we gain insight into how a layer of shared European cultural identity was constructed.
