How music and speech evolved is a mystery. Several hypotheses on their origins, including one on their joint origins, have been put forward but rarely tested. Here we report and comment on the first experiment testing the hypothesis that speech and music bifurcated from a common system. We highlight strengths of the reported experiment, point out its relatedness to animal work, and suggest three alternative interpretations of its results. We conclude by sketching a future empirical programme extending this work.
A cross-species perspective can extend and provide testable predictions for Savage et al.'s framework. Rhythm and melody, I argue, could bootstrap each other in the evolution of musicality. Isochrony may function as a temporal grid to support rehearsing and learning modulated, pitched vocalizations. Once this melodic plasticity is acquired, focus can shift back to refining rhythm processing and beat induction.