ArticleScientific reports2019
Observational data reveal evidence and parameters of contagious yawning in the behavioral repertoire of captive-reared chimpanzees (Pan troglodytes).
Article in Scientific reports, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 22 papers.
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Who cites it
22 citing papers in PubMed.
- SPREAD, a framework and open-source R toolbox to quantify behavioural contagion.Communications psychology · 2026Article
- The play fever: individual and group factors influence the contagion of play behaviour within social hominid groups.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2026Article
- The science of yawning: Exploring its physiology, evolutionary role, and behavioral impact.Journal of family medicine and primary care · 2025Review
- Chimpanzees yawn when observing an android yawn.Scientific reports · 2025Article
- 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
- Yawn Contagion and Modality-Matching in the Female-Bonded Society of Geladas (Theropithecus gelada).American journal of primatology · 2025Article
- More than a simple fixed action pattern: Yawning in drills.Primates; journal of primatology · 2024Article
- Article
- Contagious yawning in African painted dogs.Animal cognition · 2023Article
- Yawning and scratching contagion in wild spider monkeys (Ateles geoffroyi).Scientific reports · 2023Article
- No Evidence for Contagious Yawning in Juvenile Ravens (Animals : an open access journal from MDPI · 2022Article
- Yawn contagion in bonobos: Another group, another story.American journal of primatology · 2022Article
- First evidence of yawn contagion in a wild monkey species.Scientific reports · 2021Article
- Not all yawns tell the same story: The case of Tonkean macaques.American journal of primatology · 2021Article
- Yawning Is More Contagious in Pregnant Than Nulliparous Women : Naturalistic and Experimental Evidence.Human nature (Hawthorne, N.Y.) · 2021Article
- Yawn contagion in domestic pigs (Sus scrofa).Scientific reports · 2021Article
- Experimental evidence for yawn contagion in orangutans (Pongo pygmaeus).Scientific reports · 2020Article
- One thousand yawns.Primates; journal of primatology · 2020Article
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2 authors.
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Abstract
There is robust experimental evidence for contagious yawning, yet observational studies of naturalistic behavior have been fewer. Without data from real-world behavior, researchers have questioned the existence of contagious yawning and made assumptions about some parameters (e.g., the duration of the effect). We observed contagious yawning in chimpanzees to confirm/disconfirm its existence in the behavioral repertoire of this species, and if present, provide some of the missing descriptives. We recorded yawns on an all-occurrence basis from 18 captive-reared chimpanzees at the Los Angeles Zoo. We recorded identity, time, and individuals who could have been affected. We calculated a threshold for contagion by taking the mean and adding 1.96 standard deviations, constructing a response curve. Across multiple measures we see a consistent pattern in which there is a strong effect of contagion for 1.5 minutes, a less strong but still significant effect lasting up to 3.5 minutes in some measures, and no evidence of contagion beyond 3.5 minutes. From the time stamp on each yawn we were able to rule out temporal synchrony as an alternative hypothesis. Thus, contagious yawning appears to be a natural phenomenon in chimpanzees lending support to the myriad experimental and observational studies to date.
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