Universality and diversity in human song

Abstract

What is universal about music, and what varies? We built a corpus of ethnographic text on musical behavior from a representative sample of the world’s societies, as well as a discography of audio recordings. The ethnographic corpus reveals that music (including songs with words) appears in every society observed; that music varies along three dimensions (formality, arousal, religiosity), more within societies than across them; and that music is associated with certain behavioral contexts such as infant care, healing, dance, and love. The discography—analyzed through machine summaries, amateur and expert listener ratings, and manual transcriptions—reveals that acoustic features of songs predict their primary behavioral context; that tonality is widespread, perhaps universal; that music varies in rhythmic and melodic complexity; and that elements of melodies and rhythms found worldwide follow power laws.

Acoustic regularities in infant-directed speech and song across cultures

“…We used the citizen science platform https://themusiclab.org to play excerpts of each item in the corpus to listeners who were unaware of the type of vocalization they heard and who were presumably unfamiliar with many of the societies in which the vocalizations were recorded. This experiment is similar in style to other studies of form and function in vocalization 11,19–21 .…”

“…Second, people with genomic imprinting disorders, which are characterized by altered parental investment behaviors, such as those related to food consumption 53,54 , also have altered music perception ability and responses to music 55,56 . Last, consistent with classic ideas in the psychology of music 57–59 substantial evidence demonstrates that lullabies, one typical form of infant-directed song, are a human universal: singing is associated with infant care across the ethnographies of a representative sample of human small-scale societies, even after correcting for reporting biases 21 , and parents use singing to calm infants in several of the most genetically distant human societies, the Hadza, Mbuti, and !Kung San hunter-gatherers of East, Central, and South Africa 60–62 . Other forms of infant-directed song, like excitatory play songs and singing games for children, also appear to be widespread 21,63 , and parents produce them often 64 .…”

“…Infants use a distinctive alarm signal to elicit care from those around them — they cry 16 . In response, adults and children produce infant-directed vocalizations, which are known to differ reliably from adult-directed vocalizations in at least some societies, in the form of speech 17,18 or song 19–21 .…”

“…The universality of infant-directed song is also supported by evidence showing that its acoustics differ from those of other forms of music. For example, naïve listeners reliably identify lullabies as infant-directed in a cross-culturally representative sample of vocal music, both when rating multiple functions (e.g., rating the songs more highly as “used to soothe a baby” than “used for dancing” 20 ) and in a forced-choice classification task 21 . This finding echoes earlier work, wherein adult listeners were able to distinguish lullabies from love songs recorded in some foreign societies 19 .…”

“…This finding echoes earlier work, wherein adult listeners were able to distinguish lullabies from love songs recorded in some foreign societies 19 . And machine classifiers reliably distinguish lullabies from healing, dance, and love songs based only on pitches and rhythms of the vocalizations, as opposed to acoustic features merely associated with the vocalization, such as the sound of an infant crying 21 .…”