Safe Swallowing May Have Helped Lay the Groundwork for Speech

A new review explores how the demands of infant feeding and airway protection may have helped shape the precise timing needed for speech.

New York, NY — October 6, 2026 — Long before a baby says a first word, breathing and swallowing must work together to keep food out of the airway. A new review in Annals of the New York Academy of Sciences proposes that these demands of survival may have helped lay the groundwork for a defining human ability: controlling the timing of speech.

Speech requires precise control over when sound begins and ends. Producing a sequence of sounds and pauses depends on coordinating airflow with activity in the larynx, or voice box. Authors Miki Takahasi and Reiko Mazuka ask why this coordination becomes available so early in human development, before infants can speak.

Their proposal brings feeding into the story of speech evolution. Human infants undergo rapid brain growth after birth, creating substantial energy demands. The authors suggest that these demands may have favored the early introduction of foods alongside milk. Processing foods with different textures requires infants to adjust swallowing to what is happening in the mouth, placing new demands on flexible, rather than purely reflexive, control of swallowing and its coordination with breathing.

A second pressure comes from anatomy. As the voice box descends, the arrangement of the throat increases the risk of food or liquid entering the airway. The authors propose that the combined demands of flexible swallowing and reliable airway protection may have favored coordination that later supported vocal timing.

The review also highlights a possible transition around the second half of the first year. Earlier research suggests that infants first develop a more stable balance between the duration of spontaneous vocalizations and the pauses between them, then increasingly adjust vocal timing during exchanges with caregivers. This offers a possible bridge from basic bodily coordination to conversation.

Songbirds and marmoset monkeys provide additional clues. Young songbirds gradually learn to synchronize vocal sounds with breathing. In marmosets, vocal development reflects changes in the voice box as well as feedback from adults. These comparisons show how physical maturation and social experience can work together as vocal control develops.

The proposed evolutionary link remains untested. The review reports no new experiments, and the spontaneous-vocalization pattern rests on an earlier longitudinal study of five infants. Larger studies tracking feeding, breathing, and vocal interaction together could test the proposed connections. The paper does not establish that feeding practices improve speech or provide a basis for changing infant feeding recommendations.

As the authors write, speech may have “built on early-developing coordination among vital systems that were already required for survival and later became available for flexible, socially organized vocal behavior.”

About Annals of the New York Academy of Sciences

Annals of the New York Academy of Sciences is a 200+ year-old multidisciplinary journal that publishes high-impact primary research articles, reviews, and perspectives presenting significant advances across all scientific disciplines. The journal is truly multidisciplinary in scope, with contributions from researchers worldwide in the life sciences, physical sciences, social and behavioral sciences, environmental sciences, and the intersections among them. Papers are expected to advance understanding within their field, and, where possible, resonate beyond it. A hybrid journal, Ann NY Acad Sci is committed to open science and encourages authors to choose to support their research via Open Access licenses.

About the Review Authors

The review was authored by Miki Takahasi and Reiko Mazuka, both affiliated with the RIKEN Center for Brain Science in Saitama, Japan. Mazuka is also affiliated with the Research Institute for Science and Engineering at Waseda University and the International Research Institute for Neurointelligence at the University of Tokyo, both in Tokyo, Japan, and the Department of Psychology and Neuroscience at Duke University in Durham, North Carolina, USA.

Review: “Evolutionary Background of Precise Vocal–Respiratory Temporal Coordination in Human Infants.” https://doi.org/10.1111/nyas.70409

Contact
Miki Takahasi — miki.takahashi@riken.jp
Reiko Mazuka — reiko.mazuka@riken.jp