ArticleAmerican journal of primatology2021
Not all yawns tell the same story: The case of Tonkean macaques.
Article in American journal of primatology, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers.
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Who cites it
8 citing papers in PubMed, 12 citations in OpenAlex.
- Inertia and Rapid Divergence in the Evolution of Yawning: A Comparison Between Two Closely Related but Socially Different Monkeys.American journal of primatology · 2025Article
- Diving back two hundred million years: yawn contagion in fish.Communications biology · 2025Article
- Yawning in sync: implications for social cohesion in horses.Current zoology · 2025Article
- More than a simple fixed action pattern: Yawning in drills.Primates; journal of primatology · 2024Article
- Yawning and airway physiology: a scoping review and novel hypothesis.Sleep & breathing = Schlaf & Atmung · 2022Article
- Playing together, laughing together: rapid facial mimicry and social sensitivity in lowland gorillas.Current zoology · 2022Article
- Factors affecting yawning frequencies in preterm neonates.PloS one · 2022Article
- Not all yawns tell the same story: The case of Tonkean macaques.American journal of primatology · 2021Article
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Authors and funding
4 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Here we show for the first time that the plasticity in morphology and duration of yawning in Macaca tonkeana can be associated with different functional contexts. Macaca tonkeana is classified as a tolerant macaque species characterized by social interactions minimally constrained by dominance rank or kinship. Tonkean macaques, as other egalitarian species, rely on a complex facial communicative system. We found that the degree of mouth opening (ranging from covered to uncovered tooth yawns) and the duration of yawning were not strictly dependent. The shortest uncovered tooth yawns were associated with an intense locomotor/physical activity and peaked immediately after stressful social events thus indicating an increase in arousal. In contrast, longer yawns, independently from teeth exposure, were primarily associated with a relaxed state of the subject. In conclusion, our study suggests that to explore the potential different functions of yawning, it is necessary to focus on the variability of its expression both in terms of morphology and duration, because not all yawns tell the same story.
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