Rhythm evolves in the lab

The evolution of musical rhythm has been witnessed in the lab, shedding light on how certain universal features of music come to be, reports a paper published online this week in Nature Human Behaviour.

Although many different varieties of human music are found around the world, similarities do exist across cultures. Human music is inherently structured, but it is unclear how these structural regularities arise.

To investigate this phenomenon, Andrea Ravignani and colleagues simulated musical evolution in the lab. They asked participants to imitate randomly generated drumming sequences. They then asked a second group of participants to listen to the original group’s imitations and copy what they had heard. The authors find that, over time and multiple rounds of imitation, participants turned initially random sequences into rhythmically structured patterns. They find that drumming patterns developed into rhythms that were easier to learn and that contained all of the universal regularities found in world music, including grouping into beats of two or three and a regularly spaced underlying beat.

The authors conclude that their study demonstrates how basic psychological mechanisms, including working memory and the ability to perceive categories, can lead to the generation of large-scale musical universals when they are passed from person to person.