The anatomical and physiological basis of human speech production: adaptations and exaptations
Ann MacLarnon
The Oxford Handbook of Language Evolution
Edited by Kathleen R. Gibson and Maggie Tallerman
Linguistics, Phonetics and Phonology, Language and Cognition
22.1 Sound articulation
22.2 Respiratory control
22.3 Evolutionary framework
Introduction: The evolution of language
Introduction to Part II: The biology of language evolution: anatomy, genetics and neurology
Innateness and human language: a biological perspective
Evolutionary biological foundations of the origin of language: the co‐evolution of language and brain
Genetic influences on language evolution: an evaluation of the evidence
Not the neocortex alone: other brain structures also contribute to speech and language
The mimetic origins of language
Evolution of behavioural and brain asymmetries in primates
Towards an evolutionary biology of language through comparative neuroanatomy
Mirror systems: evolving imitation and the bridge from praxis to language
Cognitive prerequisites for the evolution of indirect speech
This article provides details on human speech production involving a range of physical features, which may have evolved as specific adaptations for this purpose. All mammalian vocalizations are produced similarly, involving features that primarily evolved for respiration or ingestion. Sounds are produced using the flow of air inhaled through the nose or mouth, or expelled from the lungs. Unvoiced sounds are produced without the involvement of the vocal folds of the larynx. Mammalian vocalizations require coordination of the articulation of the supralaryngeal vocal tract with the flow of air, in or out. An extensive series of harmonics above a fundamental frequency, F0 for phonated sounds is produced by resonance. These series are filtered by the shape and size of the vocal tract, resulting in the retention of some parts of the series, and diminution or deletion of others, in the emitted vocalization. Human sound sequences are also much more rapid than those of non-human primates, except for very simple sequences such as repetitive trills or quavers. Human vocal tract articulation is much faster, and humans are able to produce multiple sounds on a single breath movement, inhalation or exhalation. The unique form of the tongue within the vocal tract in humans is considered to be a key factor in the speech-related flexibility of supralaryngeal vocal tract.
Keywords: mammalian vocalizations, human speech, harmonics, fundamental frequency, vocal tract, non-human primates
Ann MacLarnon is Director of the Centre for Research in Evolutionary Anthropology at Roehampton University. She has worked on a wide variety of areas in primatology and palaeoanthropology, with an emphasis on comparative approaches. Research topics include reproductive life histories and physiology, stress endocrinology and behaviour, and aspects of comparative morphology including the brain and spinal cord. Work on this last area led to the unexpected discovery that humans evolved increased breathing control for speech.