Evolution of speech rhythm: a cross-species perspective

Abstract

Cognition and communication, at the core of human speech rhythm, do not leave a fossil record. However, if the purpose is to understand the origin and evolution of speech rhythm, alternative methods are available. A powerful tool is comparative approach: studying the presence or absence of cognitive/behavioral traits in other species, drawing conclusions on which traits are shared between species, and which are recent human inventions. Here we apply this approach to traits related to human speech rhythm. Many species exhibit temporal structure in their vocalizations but little is known about the range of rhythmic structures perceived and produced, their biological and developmental bases, and communicative functions. We review the literatures on human and non-human studies of rhythm in speech and animal vocalizations to survey similarities and differences. We report important links between vocal perception and motor coordination, and the differentiation of rhythm based on hierarchical temporal structure. We extend this review to quantitative techniques useful for computing rhythmic structure in acoustic sequences and hence facilitating cross-species research. While still far from a full comparative cross-species perspective of speech rhythm, we are closer to fitting missing pieces of the puzzle.

Cultural evolution of music and language

“…Going back to the cultural evolution of music and language, one of the critical questions would be how we have obtained this rhythmic behavior as our cultural trait. Cross-species comparative studies would be necessary to elucidate the evolutionary pathway (Ravignani et al, 2019), and research on songbirds provides a promising hypothesis that rhythm perception is linked to vocal learning capacity and vocal learning was preadapted to beat perception and synchronization of humans potentially involved a gene-culture coevolution pathway (Patel, 2021;Rouse et al, 2021).…”

Temporal modulation in speech, music, and animal vocal communication: evidence of conserved function

“…An important trend in modern biolinguistics attempts to overcome these limitations by (1) identifying the set of biologically constrained capacities on which language rests (e.g., vocal learning, articulatory control, motor sequencing, and so on), and (2) using the comparative method to assess similarities and differences across different modes of communication within and/or across species (e.g., Refs. ). A central assumption in this approach is that many of the abilities on which language depends are conserved, not only between modes of human acoustic communication like speech and music, but also between these and the vocal communication systems of other animals.…”