Open plains are not a level playing field for hominid consonant‑like versus vowel‑like calls

Gannon, Charlotte; Hill, Russell; Lameira, Adriano R

Abstract

Africa’s paleo-climate change represents an “ecological black-box” along the evolutionary timeline of spoken language; a vocal hominid went in and, millions of years later, out came a verbal human. It is unknown whether or how a shift from forested, dense habitats towards drier, open ones affected hominid vocal communication, potentially setting stage for speech evolution. To recreate how arboreal proto-vowels and proto-consonants would have interacted with a new ecology at ground level, we assessed how a series of orangutan voiceless consonant-like and voiced vowel-like calls travelled across the savannah. Vowel-like calls performed poorly in comparison to their counterparts. Only consonant-like calls afforded effective perceptibility beyond 100 m distance without requiring repetition, as is characteristic of loud calling behaviour in nonhuman primates, typically composed by vowel-like calls. Results show that proto-consonants in human ancestors may have enhanced reliability of distance vocal communication across a canopy-to-ground ecotone. The ecological settings and soundscapes experienced by human ancestors may have had a more profound impact on the emergence and shape of spoken language than previously recognized.

Citation

Gannon, C., Hill, R., & Lameira, A. R. (2023). Open plains are not a level playing field for hominid consonant‑like versus vowel‑like calls. Scientific Reports, 13(1), Article 21138. https://doi.org/10.1038/s41598-023-48165-7

• Journal Article Type: Article
• Acceptance Date: Nov 22, 2023
• Online Publication Date: Dec 21, 2023
• Publication Date: Dec 21, 2023
• Deposit Date: Dec 14, 2023
• Publicly Available Date: Jan 3, 2024
• Journal: Scientific Reports
• Electronic ISSN: 2045-2322
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 13
• Issue: 1
• Article Number: 21138
• DOI: https://doi.org/10.1038/s41598-023-48165-7
• Public URL: https://durham-repository.worktribe.com/output/2026568