ArticlePhilosophical transactions of the Royal Society of London. Series B, Biological sciences2022
Chimpanzee vowel-like sounds and voice quality suggest formant space expansion through the hominoid lineage.
Article in Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It has been retracted, and should not be counted. Cited by 14 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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14 citing papers in PubMed, 29 citations in OpenAlex.
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- Rethinking Hominin Air Sac Loss in Light of Phylogenetically Meaningful Evidence.Evolutionary anthropology · 2025Article
- Generative vocal plasticity in chimpanzees.iScience · 2025Article
- Formant analysis of vertebrate vocalizations: achievements, pitfalls, and promises.BMC biology · 2025Review
- Investigating the role of the left inferior frontal gyrus in language evolution: insights from comparative neuroscience.Frontiers in human neuroscience · 2025Review
- Chimpanzee utterances refute purported missing links for novel vocalizations and syllabic speech.Scientific reports · 2024Article
- Sketches of chimpanzee (Pan troglodytes) hoo's: vowels by any other name?Primates; journal of primatology · 2024Article
- Open plains are not a level playing field for hominid consonant-like versus vowel-like calls.Scientific reports · 2023Article
- Correction: 'Chimpanzee vowel-like sounds and voice quality suggest formant space expansion through the hominoid lineage' (2021), by GrawunderPhilosophical transactions of the Royal Society of London. Series B, Biological sciences · 2023Article
- Evolution of the human tongue and emergence of speech biomechanics.Frontiers in psychology · 2023Review
- Chimpanzees produce diverse vocal sequences with ordered and recombinatorial properties.Communications biology · 2022Article
- Chimpanzee vowel-like sounds and voice quality suggest formant space expansion through the hominoid lineage.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2022Article
- Voice modulation: from origin and mechanism to social impact.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2021Article
Corrections and comments
- Expression of concern · 2022-12-26Investigation by Journal/Publisher · Notice - Limited or No Information ·
- Erratum issued
- Expression of concern
Authors and funding
7 authors at 4 institutions in 8 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The origins of human speech are obscure; it is still unclear what aspects are unique to our species or shared with our evolutionary cousins, in part due to a lack of a common framework for comparison. We asked what chimpanzee and human vocal production acoustics have in common. We examined visible supra-laryngeal articulators of four major chimpanzee vocalizations (hoos, grunts, barks, screams) and their associated acoustic structures, using techniques from human phonetic and animal communication analysis. Data were collected from wild adult chimpanzees, Taï National Park, Ivory Coast. Both discriminant and principal component classification procedures revealed classification of call types. Discriminating acoustic features include voice quality and formant structure, mirroring phonetic features in human speech. Chimpanzee lip and jaw articulation variables also offered similar discrimination of call types. Formant maps distinguished call types with different vowel-like sounds. Comparing our results with published primate data, humans show less F1-F2 correlation and further expansion of the vowel space, particularly for [i] sounds. Unlike recent studies suggesting monkeys achieve human vowel space, we conclude from our results that supra-laryngeal articulatory capacities show moderate evolutionary change, with vowel space expansion continuing through hominoid evolution. Studies on more primate species will be required to substantiate this. This article is part of the theme issue 'Voice modulation: from origin and mechanism to social impact (Part II)'.
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