Vocal Learning Versus Speech Evolution: Untangling a False Equivalence

Abstract

The evolution of speech remains one of the most profound and unresolved questions in science. Despite significant advancements in comparative research, key assumptions about the evolutionary precursors of speech continue to be accepted with minimal scrutiny. One such assumption is the widely held belief that vocal learning—the ability to imitate and modify vocalizations—was an obligatory precondition for speech evolution. However, by the time ape-like human ancestors emerged amid Miocene's forests, the ancestors of vocal learning species already walked the Earth and flew the skies. A head-start of millions of years of vocal evolution didn't produce linguistic elephants, bats, or birds, suggesting that hominids' humble vocal beginnings were determinant for verbal evolution. Current evidence on extant great ape calls provides new details and insight into the extinct vocal forms and functions that allowed human ancestors to jump-start speech evolution. By reconsidering the evolutionary processes that led to speech, this paper advocates for a shift in focus toward the hominid biotope, body, brain, and behavior, rather than treating speech as the pinnacle endpoint of vocal learning evolution and drawing misleading parallels with far-related vocal learners.