The Developmental Trajectory of Rhythmic Abilities in Humans and Singing Primates

Rhythmicity is a composite competence that spans perceptual, motor, and socio-cognitive abilities. This is highly salient when adopting a developmental perspective, as we do in this chapter, which reviews data from humans and other singing primate taxa with a close (gibbons) or remote (indri lemurs) phylogenetic relatedness to our species. The findings we review show that rhythmicity develops as an interplay between innate maturational processes and socio-­ ecological influences, and that its underlying mechanisms have distinct developmental trajectories. Generally, however, perceptual skills emerge earlier than motor ones, and rhythmic proficiency improves as (possibly innate) motor rhythms are brought under increased cognitive control. We surmise that developmental primate data are essential for understanding the underlying mechanisms and adaptive benefits of human rhythmic competence and the human-definitory forms of communication and cooperation that it enables. As this kind of data is exceedingly scarce, a substantial task of future research will be to reduce this gap. We also identify substantial gaps in the developmental research with human children, including the need to go beyond auditory rhythms and investigate rhythms broadcasted in other modalities, to increase the cross-cultural representativeness of the samples, and to examine longitudinally the relationships between elements of the rhythmic composite.